EFFECT of PCBs (AROCLOR 1254) on SPERMATOGENESIS in TESTIS of MOUSE

多氯联苯（PCBs）是一类由人工合成的氯代芳烃类化合物，被称作潜在的内分泌干扰物。由于他们具有类雌激素和抗雄激素的性质，对雄性生殖系统造成极大危害，导致不育和一些性激素依赖的生殖功能丧失。他们能够引起内源性系统改变，类似天然性激素，并抑制性激素实现其功能。 本文目的是研究多氯联苯对雄性小鼠生殖系统的睾丸生长与发育的影响。雄性小鼠随机分成五组，每组21只。采用不同浓度Aroclor1254（0，0.5，5，50，500µg/kg）对小鼠进行灌胃染毒，每星期三次。暴露50天后处死小鼠，称其体重，睾丸重量和附睾重量，并进行精子计数和精子形态畸形实验。结果表示，处理组与对照组相比的小鼠体...Polychlorinated biphenyls (PCBs) are a group of halogenated aromatic hydrocarbons, synthetic chemicals which do not occur naturally in the environment. PCBs are considered potential endocrine disruptors. They are estrogen-like and anti-androgenic chemicals in the environment contain potentially hazardous effects on male reproductive axis resulting in infertility and other hormonal dependent reprod...学位：理学硕士院系专业：生命科学学院生物化学与生物技术系_生物化学与分子生物学学号：2172007115411

Uso de herramientas digitales para la celebración de asambleas generales no presenciales o mixta en las sociedades por acciones simplificadas

El desarrollo del derecho comercial colombiano desde la década de 1990 se enfocó en la aplicación de nuevas actividades económicas que facilitaron la adaptación a los sistemas económicos internacionales, de esta manera se fomenta el desarrollo tanto normativo como empresarial. Con el surgimiento de tipos societarios, diferente a los tradicionales, con capacidad jurídica para realizar actividades comerciales más eficientes aumentando el índice de eficacia en su ejercicio. En tal sentido la promulgación de la ley 1258 de 2008 dio lugar a la creación de la Sociedad por Acciones Simplificada (en adelante S.A.S.), consigo este tipo societario planteó la adaptación a tendencias económicas que eran aplicadas a nivel internacional, aportando ventajas considerables frente a otros tipos societarios tradicionales. Por lo anterior, es necesario estudiar el marco normativo frente a la disposición en el uso de herramientas digitales para la celebración de las asambleas generales no presenciales o mixtas como respuesta a las nuevas exigencias del mundo moderno dentro de dinámicas empresariales cada vez más competitivas que propone disposiciones más eficaces para el ejercicio y desarrollo de sus actividades comerciales, sin que con ello se pretenda vulnerar derechos a los socios y teniendo como prioridad adaptar el derecho comercial al ritmo de tendencia digital actual que maneja el derecho internacional en la actualidad.The development of Colombian Commercial Law since the 1990s focused on the application of new economic activities that facilitate adaptation to international economic systems, thus promoting both regulatory and business development. With the emergence of corporate types with legal capacity to conduct more efficient commercial activities, increasing the efficiency index in their exercise. In this sense, the promulgation of Law 1258 of 2008 led to the Joint-Stock Company creation. With it this type of company raised the adaptation to economic trends that were applied internationally, providing considerable advantages over other corporate types. Accordingly, it is necessary to study the regulatory framework regarding the provision in the use of digital tools for holding non-person or mixed general assemblies in response to new demands of the modern world within increasingly competitive business dynamics that propose the most effective provision for the exercise and development of its commercial activities without thereby attempting to violate the partners rights. On the contrary, it is intended to adapt Commercial Law to the rhythm of the current digital trend that international law currently manages

Fish and cephalopods associated with the squid Loligo vulgaris Lamarck, 1798 in Portuguese waters

Fish and cephalopod taxa occurring in association with Loligo vulgaris, in Portuguese waters between Lisbon and Vila Real de Santo António, were investigated by sampling with bottom trawling equipment between 1990-1991 and 1993-1995. The family Triglidae, the genera Pagellus and Trachurus and the four species Alloteuthis subulata, Boops boops, Callionymus lyra, and Merluccius merluccius were found, on average, in at least 75% of the trawls with L. vulgaris. Conversely, that cephalopod was found in at least 75% of the trawls with the family Trachinidae, the genera Dentex, Diplodus, Liza and Torpedo and the six species, Hyperoplus lanceolatus, Pagrus pagrus, Pomatoschistus m. minutus, Psetta m. maxima, Scophthalmus rhombus and Spicara flexuosa. An index of "affinity" (ranging from -∞ to 1) between L. vulgaris and the other taxa was used in order to highlight co-occurrences of an unlikely coincidental nature. Lists of taxa with high affinity index scores (0.5 to 1) are given for 5 different situations: all samples together; samples grouped by bottom depth; samples grouped by research cruise; research cruises grouped by season and by year. Pair wise comparisons between all taxa lists for each of the 5 situations were made, indicating a greater influence of depth than any other factor in the composition of the lists. The significance of the degree of similarity between lists of taxa, "preferred" under different circumstances and the reasons for those "preferences" are discussed

A double closed loop to enhance the quality of life of Parkinson's disease patients: REMPARK system

This paper presents REMPARK system, a novel approach to deal with Parkinson's Disease (PD). REMPARK system comprises two closed loops of actuation onto PD. The first loop consists in a wearable system that, based on a belt-worn movement sensor, detects movement alterations that activate an auditory cueing system controlled by a smartphone in order to improve patient's gait. The belt-worn sensor analyzes patient's movement through real-time learning algorithms that were developed on the basis of a database previously collected from 93 PD patients. The second loop consists in disease management based on the data collected during long periods and that enables neurologists to tailor medication of their PD patients and follow the disease evolution. REMPARK system is going to be tested in 40 PD patients in Spain, Ireland, Italy and Israel. This paper describes the approach followed to obtain this system, its components, functionalities and trials in which the system will be validated.Postprint (published version

Financial Evaluation for a Brazilian Airline to Conduct Aeronautical Components Repair in Brazil

The current economic world volatility, as well as the increasing cost of fuel and security procedures established by the worldwide authorities, force the air carriers to search for alternatives to reduce their operational costs. The maintenance costs are a significant subject for the air carriers, therefore, any cost reduction obtained without maintenance service disruption, may provide an opportunity to enhance the airline competitiveness (Fritzsche, 2014). The purpose of this research is to evaluate and compare the technical and financial aspects of performing aircraft components repair in house for a Brazilian airline versus outsourcing the servicing to a homologated company outside the country. In addition, this research will analyze the main challenges involved, such as costs involving the labor force, advantages and disadvantages of conducting the repair internally, the currency exchange and bureaucratic process applied by the Brazilian Customs to export and import components and opportunities along with companies classified as partners

Using a new high-throughput video-tracking platform to assess behavioural changes in Daphnia magna exposed to neuro-active drugs

© 2019. ElsevierOne of the major challenges that faces today regulatory risk assessment is to speed up the way of assessing threshold sublethal detrimental effects of existing and new chemical products. Recently advances in imaging allows to monitor in real time the behaviour of individuals under a given stress. Light is a common stress for many different organisms. Fish larvae and many invertebrate species respond to light altering their behaviour. The water flea Daphnia magna as many other zooplanktonic species has a marked diel vertical phototactic swimming behaviour against light due to fish predation. The aim of this study was to develop a high throughput image analysis to study changes in the vertical swimming behaviour to light of D. magna first reproductive adult females exposed to 0.1 and 1 µg/L of four psychiatric drugs: diazepam, fluoxetine, propranolol and carbamazepine during their entire life. Experiments were conducted using a new custom designed vertical oriented four 50 mL chamber device controlled by the Noldus software (Netherlands). Changes in speed, preferred area (bottom vs upper areas) and animal aggregation were analysed using groups of animals under consecutive periods of dark and apical light stimulus of different intensities. Obtained results indicated that light intensity increased the speed but low light intensities allowed to better discriminate individual responses to the studied drugs. The four tested drugs decreased the response of exposed organisms to light: individuals move less, were closer to the bottom and at low light intensities were closer each other. At high light intensities, however, exposed individuals were less aggregated. Propranolol, carbamazepine and fluoxetine were the compounds effecting most the behaviour. Our results indicated that psychiatric drugs at environmental relevant concentrations alter the vertical phototactic behaviour of D. magna individuals and that it is possible to develop appropriate high-throughput image analysis devices to measure those responses.Peer ReviewedPostprint (author's final draft

Stylet (vestigial shell) size in Octopus vulgaris (Cephalopoda) hatchlings used to determine stylet nucleus in adults

7 páginas, 1 tablas, 3 figurasThe estimation of age and growth of cephalopod stocks is a key issue for their sustainable management. Recently, several studies have successfully validated the daily deposition of growth rings in the vestigial shell or stylets of several octopus species. Octopus vulgaris eggs were incubated at two different temperatures, 18 and 22°C, until hatching to determine stylet size at hatching and assess the effect of temperature in the stylet dimensions. The 3-day-old hatchlings were sectioned transversally and 6 μm sections were stained to enhance the stylet position and visibility. The sections were observed under transmitted light microscopy at a magnification of 1000×, and the stylets identified as blue/green structures inside the mantle–funnel retractor muscle. The transversal sections of the whole paralarvae allowed the diameter of the embryonic stylet of an octopus species to be measured for the first time. The mean stylet diameter in 3-day-old paralarvae is 3.99 μm independently of the thermal conditions. Moreover, significant differences in stylet size between captive and wild paralarvae were observed; the latter showed significantly larger stylets, an indication that they are over 3 days old. Our results also indicate that the stylet nucleus is much smaller than previously thought based on measurements in stylets of juveniles and adultsThis study was supported by the projects CAIBEX (CTM2007-66108-C02-01) and LARECO (CTM2011-25929). The MultiNet® sampler used to collect wild paralarvae was funded by FEDER funds. The Portuguese Foundation for Science and Technology (FCT) supported this study through a PhD grant to Sílvia Lourenço (grant number SFRH/BD/44182/2008) and the project grant PTDC/BIA-BEC/103266/2008 to Rui Rosa.Peer reviewe

EFECTIVIDAD DEL USO DE DIATOMEAS EN LA FILTRACIÓN DE BACTERIAS DE TRANSMISIÓN HÍDRICA

La transmisión bacteriana al ser humano puede vehiculizarse por el agua y ocasionar enfermedades entéricas, por lo que el objetivo de la presente investigación es evaluar la efectividad del uso de diatomeas en la filtración de bacterias hidrotransmisibles. El estudio fue realizado en la Universidad Nacional de Chimborazo, Ecuador, desde octubre de 2019 a marzo de 2020, combinando técnicas de cultivo en agar sangre y agar MacConkey; cuantificación de colonias y filtración frente a tiempo y longitud de filtro. Se utilizaron 120 muestras de diluciones de cepas comerciales de Escherichia coli y Staphylococcus aureus para contaminar el agua de tal forma que se pudiera evidenciar la eficacia de la filtración en diatomeas de distinta procedencia. Los resultados fueron contrastados con los rangos establecidos por la Organización Mundial de la Salud y se realizaron controles positivos y negativos de los medios de cultivo y agua. Las diatomeas de Guayaquil fueron las que indujeron a una mejor filtración del agua frente a las diatomeas de Palmira. Al aplicar el lecho filtrante de 10 cm de diatomeas, se obtuvo un crecimiento de 86 UFC/100ml en 24 horas, mientras que al aumentarse la cantidad del filtro a 20 cm se observó un descenso de la carga bacteriana del agua en 21 UFC/100ml en 10 horas. De acuerdo al rango establecido por la OMS el crecimiento bacteriano disminuyó, lo que indica que los filtros de diatomeas tienen la capacidad de retener bacterias. Por esto, se presume que, al combinarlas con materiales adicionales como carbón activado, su potencial filtrante se incrementaría./ Bacterial transmission to humans can be carried by water and cause enteric diseases, so the objective of this paper is to evaluate the effectiveness of the use of diatoms in the filtration of waterborne bacteria. The study was carried out at Universidad Nacional de Chimborazo, Ecuador; from October 2019 to March 2020, combining culture techniques on blood agar and MacConkey agar, colony quantification and filtration versus filter time and length. 120 dilutions samples of commercial strains of Escherichia coli and Staphylococcus aureus were used to contaminate the water in such a way that the efficiency of filtration in diatoms of different origins could be observed. The results were contrasted with the ranges established by the World Health Organization and positive and negative controls were carried out on the culture media and water. The diatoms of Guayaquil were the ones that induced a better filtration of the water compared to the diatoms of Palmira. When applying the filter bed of 10 cm of diatoms, a growth of 86 CFU/100ml was obtained in 24 hours, while when the amount of the filter was increased to 20 cm, a decrease in the bacterial load of the water was observed by 21 CFU/100ml in 10 hours. According to the range established by the WHO, bacterial growth decreased, which indicates that diatom filters have the ability to retain bacteria. For this reason, it is presumed that, when combined with additional materials such as activated carbon, their filtering potential would increase