bluuebunny/crossref_metadata_2025 huggingface dataset:
БАГАНУУР, ТАВАНТОЛГОЙН ОРДЫН НҮҮРСНИЙ ХИМИ - БҮТЦИЙН ТӨРХ БАЙДАЛ, ОНЦЛОГ
Authors: Д Каминский Ю , Ж Дугаржав , Е Шоева Т , Б Авид , Б Төмөрчулуун
Published: August 2017

Багануур, Тавантолгой бол Монгол орны амьдрал, эдийн засагт ихээхэн ач холбогдолтой орд – уурхайнууд бөгөөд нүүрсний халуун, химийн боловсруулалтын үйлдвэрлэлийг үүсгэн хөгжүүлэх зорилт тавигдаж байгаа өнөө үед ордуудын нүүрсний хими – бүтцийн төрх байдал, урвалын идэвхийг гүнзгий судлах нь ихээхэн ач холбогдолтой. Багануур ба тавантолгойн нүүрс бол Монгол орны хүрэн ба коксждог чулуун нүүрсний түгээмэл төлөөлөгч тул бусад ордын ижил төсөөтөй нүүрсний төрх байдлын үнэлгээнд ч хөрвүүлэн ашиглах боломжтой. Энэ үүднээс бид ОХУ – ын ШУА – ийн Сибирийн салбар, Монголын ШУА- ийн хамтарсан төслийн хүрээнд хоёр ордын нүүрсний хими-бүтцийн гүнзгийрүүлсэн судалгаа явуулсан билээ. Хатуу биетэй явагддаг механохимийн урвалууд нь түүн дэх элементүүдийн идэвхийг дээшлүүлж тэдгээрийн харилцан үйлчлэлд шаардагдах эрчмийг хуримтлуулахад ихээхэн дөхөм үзүүлдэг / 1 /. Энэ судалгаанд бид механохими хийгээд орчин үеийн багажит анализийн өндөр мэдрэмжтэй хэрэгслүүдийг ашигласан тул Монголын нүүрсний тухай шинжлэх ухааныг олон шинэ баримт, өгөгдөхүүнээр баяжуулсан болно.
CLOUD COMPUTING БУЮУ ҮҮЛЭН ТООЦООЛЛЫН ВИРТУАЛЧЛАЛЫН АРГЫГ БАНКНЫ СИСТЕМД НЭВТРҮҮЛСЭН ТУРШИЛТЫН ҮР ДҮНГЭЭС
Authors: Ц Тулга , Ч Алтангэрэл , Ц Түвшинтөр
Published: August 2017

Үүлэн тооцоолол нь эдийн засгийн хувьд асар их ашигтай технологи юм. Одоогийн байдлаар томоохон байгууллагууд сервис үйлчилгээнүүдээ түгээхдээ сервис бүрийн нэг серверт байрлуулдаг, мөн мэдээллийн аюулгүй байдал, найдвартай тасралтгүй ажиллагааг хангах үүднээс сервис бүрийн нөөц серверийг байгуулах шаардлагатай байдаг нь байгууллагуудын үзүүлдэг үйлчилгээний төрлүүдээс хамааран эдийн засгийн хувьд ихээхэн хөрөнгө зарах хэрэгтэй болдог. Бид энэхүү ажлаар уламжлалт серверийн системээр хийгдсэн 10 сервис үзүүлдэг банкны системийн бүтцийг өөрчлөн үүлэн тооцооллын зарчмыг ашиглан виртуалчлал хийсэн.
МОНГОЛ ОРНЫ ЗАЛУУ ШИНЭСЭН ОЙ ҮҮСЭН БҮРЭЛДЭХ ЯВЦ БА ӨСӨЛТИЙН ЯВЦЫН ЗАРИМ ОНЦЛОГ
Authors: З Цогт , М Данилин И
Published: August 2017

Сүүлийн үед ой үүсэн бүрэлдэх явц түүний бүтээмжийг дээшлүүлэх асуудалд судлаачид ихээхээн анхаарал тавих боллоо. Ялангуяа хөрш зэргэлдээх Oрос орны эрдэмтэд дээрх чиглэлийн судалгааг 1960-аад оноос эхлэн эрчимтэй явуулж, нилээд ном бүтээл хэвлэн нийтлүүлжээ (2, 8, 9, 13, 16, 19 ). Гэвч тэдгээр ном бүтээлд гол төлөв нарс, хуш, гацуур, жодоо, хус, улиангаран ойн талаар өгүүлж, манай оронд өргөн тархсан сибир шинэсний тухай бараг хөндөгдөөгүй байна. Монгол орны залуу шинэсэн ой үүсэн бүрэлдэх явц ба өсөлтийн явцын судалгааны ажил 1979 оноос Монгол-Оросын хамтарсан Биологийн иж бүрэн экспедицийн ойн хэсгийн судалгааны ажлаар эхэлсэн ба тодорхой бүс нутгийн шинэсэн ойн өсөлт хөгжилтийн талаар Е.Н.Савин (1985), И.М.Данилин (1992), И.М.Данилин, З.Цогт (1992), З.Цогт (1993), Ч.Дугаржав (1996), Ч.Доржсүрэн (2009), В.Т.Ярмишко ба бусад (2010). И.М.Данилин (2009) нарын бүтээлд тодорхой хэмжээгээр тусгагдсан байдаг. Ой-ургамалжилтын ижил нөхцөлд үүсэн бүрэлдэж буй ойг судлахдаа түймрийн дараах, огтлолтын дараах, ямарч нөлөөнд өртөөгүй гэх мэтээр авч үзэж судлах нь зүйтэй байна.Бид өөрсдийн судалгаагаар ой үүсэн бүрэлдэх явцын тодорхой хэсэг хугацааны буюу залуу ой бүрэлдэх өсөлт, хөгжилтийн онцлогийг илрүүлэх зорилтыг тавьсан юм. Янз бүрийн бүрэлдэхүүнтэй залуу ойн үүсэн бүрэлдсэн байдлыг илрүүлэх, тэдгээрийн таксацын бүтцийн үндсэн үзүүлэлтийг тодорхойлох нь ойн нөөцийг тасралтгүй ашиглах, хамгаалах, нөөцийг нэмэгдүүлэх, бүтээмжит чанарыг дээшлүүлэх зэрэг ой судлалын олон асуудлыг шийдвэрлэхэд онолын төдийгүй практикийн чухал ач холбогдолтой. Мод огтолсон, түймэрт шатсан ойн талбай, тэрчлэн ойн зах цоорхойд байгалийн замаар залуу ой үүсэн бүрэлдэх явц бол биогеоценозын маш нарийн үйл явц юм.
HAPLOTYPES AND ALLELIC FREQUENCIES OF 12 Y-STR LOCI IN MONGOLIAN AND KOREAN MALE GROUPS
Authors: B Dashnyam , D Bayarlkhagva , Namdakov Evgeniy , G Batjil , S Ganbold
Published: August 2017

Уг судалгааг “Монгол хүний Y хромосомын генетик мэдээллийн сан”, “Цэргийн албан хаагчдын генийн мэдээллийн сан бүрдүүлэх, туршилт судалгаа“ төслүүдийн хүрээнд хийж гүйцэтгэв.
CHANGE OF THE PLANT COVER AND FOREST REGENERATION ON THE CLEAR CUTTING AREA IN PINE FOREST OF WESTERN KHENTEI
Authors: J Tushigmaa
Published: August 2017

In article show results of study and an estimation of change plant cover in pine forest of the western part Khentei upland Mongolia under influence of anthropogenous and natural factors. It is established, that after removing the main part of the stand 34 years ago in the taiga pine forest herb-fireweed-reedgrass (on the clear cutting area) of the Western Khentei floristic composition rate was 67.8% and coenotic rate-30.2% in comparision native forest. The comparative analysis showed, that the considered trial areas have reduction of occurrence and plant covering of taiga forest species and increase of specific variety forest meadow and steppe and forest steppe species.
ЦЕМЕНТИЙН ГИДРАТЖИЛТЫН БҮТЭЭГДЭХҮҮНД НАНОЦАХИУРЫН ОКСИД НЭМЭЛТИЙН ҮЗҮҮЛЭХ НӨЛӨӨ
Authors: Д Баатарцэрэн , Н Жавхлантөгс , Б Цэрэнханд
Published: August 2017

Addition of nano-silica effected to increase the content of calcium hydrasilicate and to decrease the content of calcium oxide for resulting the hydrate cement. Additional mass percent of nanosilica in all three cements of 1.0 % was important to increase compressive strength because the formation of calcium hydrasilicate is increased and the content of calcium oxide is decreased which were become from the results of X-ray diffraction analysis. Therefore, the addition of nanosilica of 1.0 % is optimal dosage. This is related to the dissolution of calcium hydroxide
ИСЛАНД УЛСЫН БАГА ТЕМПЕРАТУРТАЙ, ГАЗРЫН ГҮНИЙ ДУЛААНЫ ИЛЭРЦТЭЙ ТАЛБАЙ ДЭЭРХ ТЕМ БА МТ АРГУУДЫН ХЭРЭГЛЭЭ
Authors: Л Саранцэцэг , G Hersir P , К Arnason
Published: August 2017

Geothermal exploration involves geology, geochemistry and geophysics. In geophysical exploration, resistivity surveying plays a most important role in delineating the reservoir. The parameters that control the geothermal system show a strong response to electrical resistivity. The resistivity methods that are mostly used in geothermal exploration in Iceland are TEM (Transient electromagnetics) and MT (Magnetotellurics). The resulting resistivity cross sections and resistivity depth slices, show a shallow lying low resistivity layer and deep lying low resistivity towards the end of the cross sections
Extraction and Determination of Trace Amounts of p-Coumaric Acid in Vinegar, Carrot Juice, and Seed Extract from Silybum marianum (L.) Gaertn
Authors: Khani Rouhollah , Rostami Zeinab , Bagherzade Ghodsieh , Khojeh Vahid
Published: August 2017

In this study, for the monitoring and quantification of p-coumaric acid (p-CA) in vinegar, carrot juice, and seed extract from the plant species Silybum marianum (L.) Gaertn, an efficient and low-cost analytical method has been applied. For this purpose, a dispersive liquid–liquid microextraction (DLLME) method, followed by UV-Vis spectrophotometric detection, was used. To form a cloudy solution, a binary mixture containing ethanol as a disperser solvent and chloroform as an extraction solvent was rapidly injected by syringe into a sample solution containing p-CA. After centrifugation, dilution of the obtained organic phase was done with the proper amount of ethanol, and the phase was transferred into a micro cell for subsequent measurement. Some effective parameters for the DLLME method, such as the volume of disperser solvent and extraction solvent, pH, and salt concentration were inspected by a 24 full factorial central composite design using design Export Software. Under the optimized conditions, linearity was between 10 and 150 ng/mL, and the LOD was 2.3 ng/mL. The results of the proposed method were similar to the obtained results using a GC with flame-ionization detection method.
Homoclinic Phenomena in Ship Motions
Authors: Spyrou Kostas J.
Published: August 2017

In the article will be reviewed the changes of ship motion patterns originating from a special class of phase space phenomena identified in the nonlinear dynamics literature as homoclinic (When the term appears in italic, it will imply truly homoclinic as well as heteroclinic events). The key incident is the contact of manifolds of saddle-type (i.e., unstable) objects, which triggers a global change in the phase space flow of the dynamical system. Homoclinic phenomena are more likely to appear in extreme dynamic behavior where, usually, the effect of nonlinearity is large. Their presence can be felt through the sudden termination of oscillatory motions; or, through the emergence of motion irregularity accompanied by loss of system robustness to external excitations. Homoclinic phenomena have been identified to lurk behind some well-known manifestations of ship dynamic instability. All known ship-related cases will be reviewed and explained in the current article. Analytical and numerical tools that can be used for predicting such phenomena effectively will be discussed, as well as, practical assessment methods that are suitable for evaluating ship vulnerability. Three types of ship motion will be reviewedrolling in beam seas;surf-riding and broaching-to in following/quartering seas; anddrifting and yawing in wind. For the roll motions, the investigation will be escalated from free rolling with bias, to resonant (periodically forced) rolling and the mechanism of capsize in beam seas through safe basin erosion; to stochastic rolling and the consideration of wave grouping excitations. In astern seas, the most profound homoclinic event is the transition from ordinary surging to surf-riding. It will be explained, initially, in a deterministic context through simple dynamical analogues. Differences arising from the level of detail in the mathematical model will be discussed (many degrees of freedom, memory effect, and nonlinear waves). Then, a multifrequency wave environment will be introduced, rendering the phase space flow time-varying and incurring significant qualitative effects. The monitoring of Lagrangian structures appearing in such unsteady phase space flows can offer unique insights about nonlinear ship motions and their interactions. Wave celerity is known to correlate with the occurrence of surf-riding in regular seas, although for irregular seas, its role has been uncertain. A phenomenological approach will be reviewed for evaluating this connection. Two possible methods for celerity's calculation in irregular seas will be presented. The third area where homoclinic phenomena have been identified is planar ship motions under strong wind loads. Two particular cases will be addressed: the transition from a course-keeping pattern to a turning motion pattern as the rudder angle is varied; and phenomena of "head wind" ship operation, under sluggish rudder control. The article will conclude with some thoughts as to the future direction in the field.
Various Aspects of Bollard Pull Tests and Analysis of Test Results
Authors: Dev Arun Kr
Published: August 2017

The static force exerted on a hawser at zero ship speed by a vessel, otherwise known as the bollard pull, is one of the key performance indicators of Tugs, Anchor Handling Tugs (AHTs) and Anchor Handling Tug Supply Vessels (AHTSVs). The value of bollard pull is considered critical as it defines the functionality and performance of the vessel. When a company decides on chartering a vessel, a definite prerequisite considered is the value of the bollard pull. The value may be obtained via three ways: calculations, model-testing, and full-scale trials. The latter is often used officially to certify the vessel's bollard pull rating, with the presence of the vessel's owners, surveyors, and any other third parties. The tests and trials follow a set of guidelines provided by classification societies but do not have a standardized set of rules. Therefore, disagreements often arise over the results of such tests and trials. Tests are often carried without any load cells measuring the shaft power to ascertain the brake horsepower (BHP). Simply, engine rpm/ rating is used to fix the 100% maximum continuous rating (MCR) which often in the range of 105–108% MCR. Some of the parties involved in certifying the correct bollard pull tests (BPTs) do not even understand what is all about the bollard pull. Everybody is looking for a higher figure for the bollard pull on the certificate when the reality is different. The author examines and discusses the broad spectrum of factors that affects the "true" value of the bollard pull and explains why such a standardized set of mandatory BPT and the trial code is deemed necessary. The author also presents some of the interesting BPTs data to show the differences in various ways of conducting BPTs.

1. Introduction

The bollard pull (BP) is the zero speed pulling/pushing capability of a vessel, i.e., Tugs, Anchor Handling Tug (AHTs), Anchor Handling Tug/ Towing Supply Vessel (AHTSVs), trawlers, etc. It is considered as one of the key practical performance indicators of the above-mentioned vessels, measuring the usefulness of the vessel in a stranding scenario or in holding large vessels such as tankers or towing a rig.
Fatores que ocasionam a não adesão das mulheres na realização do papanicolau na cidade de Sitio do Quinto (BA), Brasil
Authors: Santos Bruna Luisa Nilo , Sobrinho José Renaldo Prata , Pereira Renan Sallazar Ferreira , Brandão Igor Macedo , Carvalho Fábio Luiz Oliveira de
Published: August 2017

É de grande relevância a realização do exame Papanicolau, sendo uma das principais formas de rastreamento do câncer de colo do útero, onde uma vez, que descoberto no início tem um alto percentual de cura. O Ministério da Saúde, devido a isto, implementou a Política de Atenção à Saúde da Mulher, com intuito preventivo. Este tipo de câncer é o mais frequente nas mulheres de 25 a 59 anos, estando em terceiro lugar como o de maior incidência, tendo como uma das suas principais causas o HPV. Desta forma, esta pesquisa tem o objetivo de entender quais fatores levam as mulheres da cidade de Sitio do Quinto-BA a não realizarem o exame citopatologico. Foram entrevistadas 30 usuárias das unidades básicas de saúde, em suas residências e local de trabalho, onde os resultados mostraram que a maior parte delas tem entre 41 a 50 anos (39%), a situação conjugal 43,3% são casadas, 50% analfabetas, possuem em média renda familiar de 1 salário mínimo. Em seus antecedentes obstétricos 43,3% falaram ter de 1 a 2 filhos, 0 a 1 gestação (23,3%), 63,3% afirmaram não ter antecedentes familiares com câncer. 76,6% relataram frequentar o PSF, quando indagadas com que frequência, 39,1 % falaram que as vezes e 39,1% disseram que sempre. Quando perguntei sobre a realização do exame 60% afirmaram nunca ter realizado, onde 31% delas disseram que o principal motivo era a falta de tempo. 66,6% afirmam saber da importância do exame, e que foram informadas através dos ACS (agentes comunitários de saúde) (52,1%), sobre o local em que receberam a informação 33,35 afirmaram ser em outros, 100% delas afirmaram nunca ter recebido convite da unidade de saúde de atividades acerca do câncer de colo do útero e exame preventivo. O trabalho é quantitativo, bibliográfica, tendo uma análise estatística descritiva, observacional de caráter exploratório, sendo um estudo epidemiológico de corte transversal e amostragem estratificada. O resultado da pesquisa apontou que há uma grande relação entre fatores socioeconômicos a realização do Papanicolau, e uma grande fragilidade relacionada as ações voltadas a promoção de saúde na cidade.
The use of the results as capitalization strategy of agricultural co-operatives in Paraná
Authors: Rodrigues Jessé Aquino , Primo Fiorentin Adilson , Sparano Martins Tomas
Published: August 2017

With significant importance in the economic background in Parana, the agricultural cooperatives grow each year seeking better results for its members. Throughout their history, several difficulties were found in their development, since a great amount of investment has been necessary to support their practices throughout the years, directly affecting their capital structure. Hence, looking for better capitalization mechanisms has become a challenge for most coops in Parana. The aim of this paper is to verify if the co-operatives in the state use their annual results as a way of capitalization and how much of the result is given back to their members. We used secondary data and general meetings records in a non-probabilistic sample of the 15 biggest co-operatives in the state. We used income criteria based on the 2014 data, we verified that 65% of the total income is addressed to mandatory legal funds and funds created for the cooperatives development and capitalization, moreover, 4% were allocated to the members’ social capital’s share and finally 30% are given back to their members in the form of financial resources, proving the use of surpluses as a capitalization strategy of the cooperatives. Briefly, this assessment sought to contribute to the discussion about cooperative capitalization, demonstrating the importance of generating positive results and its influence on the capitalization strategy.
Analysis of budget changes in the municipality of Parnaíba Santana in the exercises of 2013 and 2014.
Authors: Scalabrin Cardoso Gomes Maria Helena , Ferreira Vanderlei , Pereira Rios Ricardo , Goulart Verci Douglas
Published: August 2017

The aim of this study was to analyze the changes in the public budgets in Santana de Parnaíba, during the years of 2013 and 2014.  The methodology used in this study started from the existing Laws, academic publications, followed by research on the electronic site. The analytical bases were those in the Transparency Index of Municipal Public Management (ITGP-M), followed by exploratory researches with the responsible for preparing the public budget.  The study reveals that in the year 2014 were proposed 31 Decrees, which the amounting of R$ 129 million in additional credits. The same happened in the year 2013, R$119 million. The Municipal Secretaries of Education and Health received together 70.52% of the funds. The justifications given by the responsible officers regarding these supplementary credits were not compatible with acts of good management, since the changes were occurred in the early months of each year, characterizing, at least, an inadequate planning. The evidence of inadequate practices, generate questions and send warning signals that is an indicative of monitoring the municipal budget.
The effects of tax policy and economic regulation on the companies of the electricity sector in Brazil
Authors: Martins Duarte Costa Danielle , Terra de Andrade Diego César , Abrantes Luiz Antônio , Marques Ferreira Marco Aurélio
Published: August 2017

The objective of this study was to analyze the possible effects of the electric sector's regulatory regulations and the enactment of laws 10,637 / 2002 and 10,833 / 2003 on the collection of federal PIS and COFINS taxes and on pricing of electric energy tariffs, identifying the determinant factors for fixing them. The multivariate analysis was used as an analytical approach, taking as reference the multiple panel regressions. In general, there was a 113% increase in the payment of PIS and COFINS social contributions after the enactment of Law 10.833/2003, indicating that the right to deduct credits on certain factors of production was not obtained by companies in the electric energy sector increasing, therefore, the tax burden of companies. The direct consequence of this result was the increase in the average electric energy tariff charged from residential consumers, especially after the 2004 period. In this sense, after a 153% increase in the PIS and COFINS rates, and after the concessionaires' right to revise their tariffs when there was an increase in costs, including taxes, there was a considerable increase in the average tariff of electric power in the order of 2.8% and 8.1%, respectively, higher than the increases in their production costs. Therefore, it can be inferred that the increase in electric energy tariffs during the study period was mainly due to the increase of the tax burden and the regulatory factors since the factors of production were not significant in the model.
Sustainable characteristics and port competitive reflections: a case study in the Ponta do Felix port terminal
Authors: Monte Christiano Ellian , Moreira Campos da Cunha Amarante Janaína Gabrielle
Published: August 2017

The present study aimed to analyze how sustainable actions are related to the competitive port, with the best market positioning and respective regional socio-environmental development, still incipient research in the national scope. To achieve this objective, a methodological framework was adopted with the application of semi-structured interviews with the directors of the Ponta do Félix Port Terminal, whose analytical categories focus on John Elkington's three pillars of sustainability, as well as Strategies Competitive Generics, by Michael Porter. From the content analysis, following the guidelines of Bardin, two predominant strategies were verified: (i) Differentiation, considering that the service rendering is considered unique and differentiated in operations and quality; And (ii) Approach, which characterizes a service aimed at customers who work with special products, demanding strict environmental demands. This study confirms, starting from the "Porter Hypothesis", the relationship between sustainability and competitiveness in a company, stimulating innovation and cost reduction, thus obtaining a competitive advantage due to the adjustments to environmental regulations. The study brings practical contributions to managers of the port segment about the organizational competitiveness linked to environmental quality standards, such propositions can guide the concentration of new positions under the sustainable port perspective as a business strategy. In addition, from this study also emerge contributions to the scientific community regarding the filling of the literature gap in the area in question.
Developmental adaptations of trypanosome motility to the tsetse fly host environments unravel a multifaceted in vivo microswimmer system
Authors: Schuster Sarah , Krüger Timothy , Subota Ines , Thusek Sina , Rotureau Brice , Beilhack Andreas , Engstler Markus
Published: August 2017

The highly motile and versatile protozoan pathogen Trypanosoma brucei undergoes a complex life cycle in the tsetse fly. Here we introduce the host insect as an expedient model environment for microswimmer research, as it allows examination of microbial motion within a diversified, secluded and yet microscopically tractable space. During their week-long journey through the different microenvironments of the fly´s interior organs, the incessantly swimming trypanosomes cross various barriers and confined surroundings, with concurrently occurring major changes of parasite cell architecture. Multicolour light sheet fluorescence microscopy provided information about tsetse tissue topology with unprecedented resolution and allowed the first 3D analysis of the infection process. High-speed fluorescence microscopy illuminated the versatile behaviour of trypanosome developmental stages, ranging from solitary motion and near-wall swimming to collective motility in synchronised swarms and in confinement. We correlate the microenvironments and trypanosome morphologies to high-speed motility data, which paves the way for cross-disciplinary microswimmer research in a naturally evolved environment.
Environmental cystine drives glutamine anaplerosis and sensitizes cancer cells to glutaminase inhibition
Authors: Muir Alexander , Danai Laura V , Gui Dan Y , Waingarten Chiara Y , Lewis Caroline A , Vander Heiden Matthew G
Published: August 2017

Many mammalian cancer cell lines depend on glutamine as a major tri-carboxylic acid (TCA) cycle anaplerotic substrate to support proliferation. However, some cell lines that depend on glutamine anaplerosis in culture rely less on glutamine catabolism to proliferate in vivo. We sought to understand the environmental differences that cause differential dependence on glutamine for anaplerosis. We find that cells cultured in adult bovine serum, which better reflects nutrients available to cells in vivo, exhibit decreased glutamine catabolism and reduced reliance on glutamine anaplerosis compared to cells cultured in standard tissue culture conditions. We find that levels of a single nutrient, cystine, accounts for the differential dependence on glutamine in these different environmental contexts. Further, we show that cystine levels dictate glutamine dependence via the cystine/glutamate antiporter xCT/SLC7A11. Thus, xCT/SLC7A11 expression, in conjunction with environmental cystine, is necessary and sufficient to increase glutamine catabolism, defining important determinants of glutamine anaplerosis and glutaminase dependence in cancer.
Occasional hybridization between a native and invasiveSeneciospecies in Australia is unlikely to contribute to invasive success
Authors: Dormontt Eleanor E. , Prentis Peter J. , Gardner Michael G. , Lowe Andrew J.
Published: August 2017

Background

Hybridization between native and invasive species can facilitate introgression of native genes that increase invasive potential by providing exotic species with pre-adapted genes suitable for new environments. In this study we assessed the outcome of hybridization between nativeSenecio pinnatifoliusvar.pinnatifoliusA.Rich. (dune ecotype) and invasiveSenecio madagascariensisPoir. to investigate the potential for introgression of adaptive genes to have facilitatedS. madagascariensisspread in Australia.

Methods

We used amplified fragment length polymorphisms (141 loci) and nuclear microsatellites (2 loci) to genotype a total of 118 adults and 223 seeds fromS. pinnatifoliusvar.pinnatifoliusandS. madagascariensisat one allopatric and two shared sites. We used model based clustering and assignment methods to establish whether hybrid seed set and mature hybrids occur in the field.

Results

We detected no adult hybrids in any population. Low incidence of hybrid seed set was found at Lennox Head where the contact zone overlapped for 20 m (6% and 22% of total seeds sampled forS. pinnatifoliusvar.pinnatifoliusandS. madagascariensisrespectively). One hybrid seed was detected at Ballina where a gap of approximately 150 m was present between species (2% of total seeds sampled forS. madagascariensis).

Conclusions

We found no evidence of adult hybrid plants at two shared sites. Hybrid seed set from both species was identified at low levels. Based on these findings we conclude that introgression of adaptive genes fromS. pinnatifoliusvar.pinnatifoliusis unlikely to have facilitatedS. madagascariensisinvasions in Australia. Revisitation of one site after two years could find no remainingS. pinnatifoliusvar. pinnatifolius, suggesting that contact zones between these species are dynamic and thatS. pinnatifoliusvar. pinnatifoliusmay be at risk of displacement byS. madagascariensisin coastal areas.
Biological effects of carbon nanotubes generated in forest wildfire ecosystems rich in resinous trees on native plants
Authors: Lara-Romero Javier , Campos-García Jesús , Dasgupta-Schubert Nabanita , Borjas-García Salomón , Tiwari DK , Paraguay-Delgado Francisco , Jiménez-Sandoval Sergio , Alonso-Nuñez Gabriel , Gómez-Romero Mariela , Lindig-Cisneros Roberto , Reyes De la Cruz Homero , Villegas Javier A.
Published: August 2017

Carbon nanotubes (CNTs) have a broad range of applications and are generally considered human-engineered nanomaterials. However, carbon nanostructures have been found in ice cores and oil wells, suggesting that nature may provide appropriate conditions for CNT synthesis. During forest wildfires, materials such as turpentine and conifer tissues containing iron under high temperatures may create chemical conditions favorable for CNT generation, similar to those in synthetic methods. Here, we show evidence of naturally occurring multiwalled carbon nanotubes (MWCNTs) produced fromPinus oocarpaandPinus pseudostrobus,following a forest wildfire. The MWCNTs showed an average of 10 walls, with internal diameters of ∼2.5 nm and outer diameters of ∼14.5 nm. To verify whether MWCNT generation during forest wildfires has a biological effect on some characteristic plant species of these ecosystems, germination and development of seedlings were conducted. Results show that the utilization of comparable synthetic MWCNTs increased seed germination rates and the development ofLupinus elegansandEysenhardtia polystachya, two plants species found in the burned forest ecosystem. The finding provides evidence that supports the generation and possible ecological functions of MWCNTs in nature.
RNA expression and disease tolerance are associated with a “keystone mutation” in the ochre sea star Pisaster ochraceus
Authors: Chandler V. Katelyn , Wares John P.
Published: August 2017

An overdominant mutation in an intron of the elongation factor 1-α (EF1A) gene in the sea star Pisaster ochraceus has shown itself to mediate tolerance to “sea star wasting disease”, a pandemic that has significantly reduced sea star populations on the Pacific coast of North America. Here we use RNA sequencing of healthy individuals to identify differences in constitutive expression of gene regions that may help explain this tolerance phenotype. Our results show that individuals carrying this mutation have lower expression at a large contingent of gene regions. Individuals without this mutation also appear to have a greater cellular response to temperature stress, which has been implicated in the outbreak of sea star wasting disease. Given the ecological significance of P. ochraceus, these results may be useful in predicting the evolutionary and demographic future for Pacific intertidal communities.
Sexual ratio in populations of Sparisoma radians and Sparisoma atomarium at Los Roques Archipelago, Venezuela: An evolutionary approach
Authors: De-Nóbrega JR , Villamizar E
Published: August 2017

A comparative study of two populations of Sparisoma radians and one population of Sparisoma atomarium indicates significant differences in the overall and size-specific adult sex ratio, as well as in the width of the critical size class for sex change of these hermaphrodite marine fish species. Sparisoma atomarium shows an overall sex ratio more biased to females and a rather sharp change in size-specific sex ratio than S. radians, revealing a narrower critical size class for sex change. The differences observed between species agree with that reported in another study, which outlines an evolutionary explanation based on the different mating systems of these species. Significant differences were detected in the form and central localization of size distribution between the two samples of S. radians, accompanied with a displacement in the respective size class for sex change and the constancy in overall sex ratio. This result, in addition to the condition of sex ratio biased to females in the three populations, agrees with predictions of evolutionary models of sequential hermaphroditism.
Evaluation of oxytetracycline concentration in shrimp postlarval tissues offered through Artemia nauplii and medicated bath
Authors: Roque A , Cuenca C , Espinosa A , Bermúdez C , Bolan C , Gómez-Gil B
Published: August 2017

In Mexico, oxytetracycline is commonly applied to shrimp larval rearing systems to control bacterial problems; however, it is not known how much oxytetracycline is incorporated by the shrimp. The present study aimed to measure the levels of oxytetracycline incorporated by Litopenaeus vannamei shrimp postlarvae offered by two different administration routes: bioencapsulated in Artemia franciscana nauplii and applied directly in the seawater. Five treatments were used: postlarvae medicated through conventional bath (20 ppt) and fed Artemia nauplii (BATH), postlarvae fed Artemia nauplii enriched with oxytetracycline (19 mg meal–1) and Rich®, a commercial lipid mix (R-OTC), postlarvae fed Artemia nauplii enriched with oxytetracycline (19 mg meal–1) (OTC), postlarvae fed Artemia nauplii enriched with Rich® (RICH), and postlarvae fed with Artemia nauplii (control). Treatments were applied for seven days and postlarvae from each treatment were sampled daily to measure the levels of oxytetracycline incorporated through high performance liquid chromatography (HPLC). Higher incorporation of oxytetracycline in the shrimp was found in the BATH treatment. Values did not vary much among days within the treatments. Rich® improved the amount of oxytetracycline incorporated by the shrimp. By day 7, the mean antibiotic determinations were as follows: OTC, 5.77 ± 0.6 ∞g g–1; Rich® + OTC, 18.98 ± 2.8 ∞g g–1; and BATH, 26.3 ± 8.1 ∞g g–1 of shrimp extract. An antibiotic dose of 4 times the minimum inhibitory concentration (MIC) is recommended in order to achieve therapeutic doses in the organisms to be treated. The results from the chromatography analysis on the shrimp body showed that only 0.15 of the MIC (303.98 ∞g mL–1) reported was in fact detected in the shrimp in the highest treatment. Oxytetracycline is water-soluble, and perhaps its bioencapsulation for treatment purposes is not feasible. As for the medicated bath, a higher concentration is required to achieve a therapeutic dose in the shrimp tissues.
Effects of Nordmøre-grid angles, profiles and other industry-developed modifications on catches in an Australian penaeid-trawl fishery
Authors: Broadhurst MK , Young DJ , Damiano C
Published: August 2017

In response to claims that conventional Nordmøre-grids used in the Clarence River penaeid-trawl fishery were occasionally being fouled or blocked during fishing, two experiments were done to examine the utility of modified grids with different installation angles, sizes and profiles, and alternative industry-developed, behavioral-type bycatch reduction devices (BRDs). In experiment 1, a conventional Nordmøre-grid (600 mm in length, installed at 45º) was compared against a longer grid (1200 mm in length, installed at 21º) and two locally-developed, behavioral-type BRDs. While slightly more difficult to operate than the conventional design, the longer Nordmøre-grid retained similar quantities of penaeids and bycatch; in contrast, both behavioraltype BRDs retained significantly (up to five times) more bycatch and were considered ineffective for use in this fishery. In experiment 2, the conventional Nordmøre-grid was tested against three modified Nordmøre-grids, including a 600-mm-long grid with a curved profile and installed at 45º, and two grids, both 900 mm in length and installed at 28º, but with flat and curved profiles. Only the curved 900-mm Nordmøre-grid caught significantly fewer penaeids and bycatch, although both of the curvedprofile grids appeared to facilitate the release of debris from the trawl. The results are discussed in terms of fishery-specific factors that probably contributed towards the performances of the various BRDs.
Evaluation of two treatments in polychaete worm intensity associated with Crassostrea gigas (Thunberg, 1873) oyster valves
Authors: Gallo-García MC , Ulloa-Gómez MG , Godínez-Siordia DE
Published: August 2017

This study evaluates the effect of weekly immersion baths in fresh water and a 0.2% solution of calcium hydroxide (lime) on the intensity of fouling polychaete worms in Crassostrea gigas oysters. Initially, 135 juvenile oysters (with an average length of 2.75 ± 0.25 cm and a mean wet weight of 4.33 ± 0.96 g) were randomly assigned to three groups with three replicates each. Two groups were treated for 10 minutes with lime and fresh water, respectively, and a third group remained as control. Fouling polychaete intensity and the bivalve length and weight were obtained every 15 days. Every week oyster survival was registered for each treatment and water parameters were measured at the culture site. Significant differences (P < 0.05) in worm intensity were found between the two bath treatments and the control. The lime treatment showed the lowest intensity (number of mud tubes/oyster) in all the sampling days, with no increase in intensity during the last experimental month. There were no significant differences (P > 0.05) in final survival, final length, final weight and final condition index of the oysters among treatments after 112 days of study.
Oxygen consumption, ammonium excretion and osmoregulatory capacity of Litopenaeus stylirostris (Stimpson) exposed to different combinations of temperature and salinity
Authors: Denisse-Re A , Díaz F , Sierra E , Gómez-Jiménez S
Published: August 2017

The physiological responses of the blue shrimp were determined by exposing the organisms to temperatures of 23ºC, 28ºC and 33ºC, and salinities of 10, 15, 20, 25, 30, 35 and 40‰. Oxygen consumption of Litopenaeus stylirostris exposed to experimental salinities increased in direct relationship with temperature, even though at 28ºC the metabolic rate was steady. The ammonium excretion rate in juvenile shrimp acclimated at 23ºC and 33ºC was related to the pattern of osmoregulation, increasing when the shrimp were hyper-regulators and decreasing when they were hypo-regulators. The ammonium excretion rate remained constant in shrimp kept at 28ºC. The osmoregulatory capacity of the juveniles indicated that they were hypo-regulators and hyper-regulators in salinities above and below the isosmotic point, this capacity decreasing in organisms kept at 33ºC and exposed to higher salinities. The isosmotic point obtained ranged from 676.8 to 700.7 mmol kg–1 (23.7–24.6‰). The values of the slopes between the osmotic concentration of the external medium and the hemolymph of shrimp acclimated at 23ºC, 28ºC and 33ºC were 0.25, 0.17 and 0.3, respectively; the lowest value was obtained for juveniles maintained at 28ºC, being strong regulators in this condition. To optimize the culture of L. stylirostris under controlled conditions, we propose that it be cultivated in salinities of 25‰ and temperatures of 28ºC, considered the optimum conditions because in these environments the organisms are free of stress and their growth therefore increases.
ENSO effects on primary production off Baja California
Authors: Hernández-Torre B , Gaxiola-Castro G , Nájera-Martínez S
Published: August 2017

Long-term time series of total primary production (PT) from 1969 through 2002, associated with ENSO (El Niño/Southern Oscillation) events are presented for the region off northern Baja California. PT was calculated using an empiric model in six inshore and offshore grids of the CalCOFI-IMECOCAL network in the southern California Current. In general, PT anomalies were positive from 1970 to 1975, with a period average of 0.024 GtC yr–1 for the study lines. PT changed to negative anomalies after ENSO 1976–77, with a decrease in productivity for at least 20 years, reinforced by the ENSO events of 1982–84, 1987–88, 1992–93 and 1997–98. Annual time series of PT anomalies show that during the ENSO events, values diminished by ~20% in the study area. Long-term PT changes (1976–97) originated a reduction of 0.007 GtC yr–1 (~70%), in relation to the higher production of the early 1970s (1970–75). Mean PT during 1997–98 was 0.014 GtC yr–1, increasing during 1999–2002 (0.023 GtC yr–1) toward similar values calculated for the early 1970s. Superposed Epoch Analysis proved the statistical association between the ENSO events and PT, with the probability of high production one year before (–1), diminishing during the key year (0), and recovering one year after (+1) the event off Baja California. Complete (1950–2002) PT time series showed greatest variance in the 1.43-year period. Small pelagic fish biomass estimated for inshore stations of lines 90 and 107 dropped below 200 × 103 tons after the 1976–77 period, with a recovering trend after 2000.
Effect of UV radiation on the genetic inactivation of sperm of the bullseye puffer Sphoeroides annulatus (Jenyns, 1842)
Authors: Arias-Rodríguez L , Rodríguez-Ibarra LE , Del-Valle-Pignataro G
Published: August 2017

Genetic (DNA) inactivation of fish sperm with ultraviolet irradiation is generally accompanied by a paradoxical effect on survival rates (Hertwig effect). In the present study, sperm samples from ten male bullseye puffer fish (Sphoeroides annulatus) were diluted 1:50 using Cortland's extender solution and used to test the effect of nine ultraviolet doses (0.2–1.0 J cm–2) on motility time in seconds, motility index, and embryo survival rate after fertilizing eggs from five bullseye puffer females. Motility time of sperm irradiated with 0.2–0.9 J cm–2 were not statistically different from the controls, but sperm irradiated with a dosage of 1.0 J cm–2 dosage had significant lower motility time. Motility indices (MI) allowed for the statistical differentiation of four groups in relation to their response to different radiation doses: the first had high MI, and included the controls and 0.2–0.3 J cm–2 treatments; the second had lower MI and included the 0.4–0.7 J cm–2 treatments; the third showed recovery of MI and included the 0.8–0.9 J cm–2 treatments; and the fourth showed the lowest MI with the 1.0 J cm–2 treatment. Embryo survival was highest for the controls and 0.2 J cm–2 treatment, decreasing in the 0.3–0.4 J cm–2 treatments, increasing again in the 0.5–0.8 J cm–2 treatments, until reaching lowest survival in the 0.9–1.0 J cm–2 treatments. These results indicate that the best ultraviolet dosage to achieve genetic inactivation of sperm of this species is close to 0.7 J cm–2, a dosage in which fish fry showed typical haploid syndrome characteristics.
Calibration of Sr/Ca and Mg/Ca paleothermometers in coral Porites sp. from San Benedicto Island, Revillagigedo Archipelago, Mexico
Authors: Villaescusa JA , Carriquiry JD
Published: August 2017

A better understanding of the global climate system depends on our ability to expand the limited instrumental records of sea surface temperature (SST) of tropical regions. The Sr/Ca and Mg/Ca ratios contained in the growth bands of corals have proved to be an accurate tool to reconstruct SST variability. In this study we show the calibration obtained from the seasonal geochemical measurement of the Sr/Ca and Mg/Ca molar ratios in the skeleton of coral of the genus Porites from San Benedicto Island, in the Revillagigedo Archipelago, and SST. The geochemical ratios measured (precision ±0.2%, 2σ) showed a high seasonal covariation closely related to the region's SST. The calibration equation calculated for the Sr/Ca–SST relation (n = 52) was Sr/Ca (mmol mol–1) = 10.467 (±0.067) – 0.0524 (±0.003) × SST (r2 = 0.894), and for the Mg/Ca?SST relation it was Mg/Ca (mmol mol–1) = 1.550 (±0.095) + 0.0956 (±0.0043) × STT (r2 = 0.906). When comparing the SST time series reconstructed from the Sr/Ca and Mg/Ca ratios with the mean SST of a spatial grid of 2º × 2º (longitude × latitude) that comprises San Benedicto Island, we found a high concordance between both temperatures, showing the robustness of the procedure. A drawback of this method is that no unique calibration exists for the Sr/Ca–SST and Mg/Ca–SST relations, and the different calibrations published generate discrepancies of up to 8ºC in the calculated temperature, regardless of whether the thermal sensitivity (i.e., the slope of the paleotemperature equation) of corals is similar. We therefore concluded that the Sr/Ca and Mg/Ca paleothermometers are highly reliable in this region of the Pacific Ocean, provided that a specific equation exists for the area under study.
Morphodynamics of a mesotidal, exposed, low tide terrace beach (Faro, southern Portugal)
Authors: Anfuso G , Ruiz N
Published: August 2017

A field assessment of microtopographic changes and disturbance depth was carried out during a tidal cycle at Faro beach, southern Portugal. This mesotidal beach presents a well developed low tide terrace, wide and flat (tan ß = 0.02), and an important (tan ß = 0.11) foreshore slope. Erosive processes, related to sea waves, produced a beach profile rotation around mean sea level. Disturbance depth presented great variations according to beach morphology and sedimentology as well as wave characteristics, factors that controlled breaking wave type. Plunging breakers prevailed in the upper and middle foreshore, greatly affecting bottom sediments that recorded disturbance values of 25% of significant breaking wave height. Spilling breakers prevailed in the low tide terrace, with average disturbance values of about 4%. Lastly, values of disturbance depth obtained with two different methods, rods and plugs or rods with loose-fitting washers, were compared. The second method gave higher values of disturbance with coarser sediments.
Susceptibility of Litopenaeus schmitti and Cherax quadricarinatus to white spot syndrome virus (WSSV)
Authors: Unzueta-Bustamante ML , Silveira-Cofficny R , Prieto AA , Aguirre-Guzmán G , Vázquez-Juárez R.
Published: August 2017

Bioassays were carried out in a closed system to evaluate the susceptibility of Litopenaeus schmitti and Cherax quadricarinatus to white spot syndrome virus (WSSV) using L. vannamei as the positive control reference species. Animals were injected intramuscularly (20 ∞L shrimp–1) with a WSSV preparation obtained from the Aquaculture Pathology Laboratory of the University of Arizona. These infected organisms were reared separately in their respective experimental tank. Susceptibility to WSSV was significantly greater in L. vannamei than in the other two species (P < 0.05). The histological analysis showed characteristic inclusion bodies of WSSV in these three crustacean species, with a different distribution of infection depending on the tissue and species. In situ hybridization also showed these signs of infection in hemocytes and hepatopancreas.
Microgastropods associated with the natural bank of Arca zebra (Swainson, 1833; Mollusca: Bivalvia) located in Chacopata, Sucre State, Venezuela
Authors: Narciso S , Prieto-Arcas A , Acosta-Balbás V
Published: August 2017

The objective of this study was to analyze the taxonomy of microgastropods associated with the bivalve Arca zebra, an important fishing resource of the northern coast of Venezuela. The samples were obtained in the area of Chacopata, Sucre State, Venezuela. A total of 381 gasteropods were collected belonging to 25 species included in 12 families. The families with the highest number of species were Margellinidae (4), Collumbelidae (4) and Fisurellidae (3). Of the total of species collected, seven (Marginella haematita, Lucapina sowerby, Cantharus cancellarius, Crassispira tampanensis, Pyrgocytara coxi, Monilispira leusosyma and Terebra nasulla) represent new records for Venezuela, but can be catalogued as typical of the tropical western Atlantic.
Uptake, depuration and effect of cadmium on the green mussel Perna viridis (L. 1758) (Mollusca: Bivalvia)
Authors: Narváez N , Lodeiros C , Nusetti O , Lemus M , Maeda-Martínez AN
Published: August 2017

We evaluated the effect of a sublethal concentration of cadmium (0.04 µg Cd L–1) on the physiological condition of the juvenile green mussel Perna viridis (22.3 ± 2.33 mm shell height), collected in Guayacán, Sucre State, Venezuela. The mussels were exposed to the sublethal concentration for 7 days, and were then depurated during 52 days simultaneously in the laboratory and in the field in plastic baskets suspended from a long line. In both conditions, the concentration of cadium was measured and different physiological indices were determined: oxygen consumption, ammonia excretion, total protein content in tissues, RNA/DNA ratio, and height and mass of the shell and tissues. No significant differences in the physiological indices were obtained during the depuration process in the laboratory but, in general, all the indices tested increased during depuration in the field. The RNA/DNA index showed great variability, proving to be unsuitable to evaluate the toxic effect of cadmium; however, total protein content, shell and tissue height and mass and, particularly, oxygen consumption and ammonia excretion rate proved to be suitable to evaluate the physiological condition of mussels exposed to subletal concentrations of xenobiotics.