Ecologia do fitopl��ncton em ��reas de cultivo de Til��pia do Nilo, Oreochromis niloticus, em tanques-rede no a��ude Ministro Jo��o Alves, Parelhas, Rio Grande do Norte

The dams are limnic ecosystems of great importance for its multiple uses, among them, water supply for the public and to culture of artisanal fish are most relevant. The aim of the present study is to evaluate the physical-chemical characteristics and the phytoplankton community in two chosen sites (Point 1 littoral zone of point source; Point 2 pelagic zone of non-point source) of the Minister Jo��o Alves dam, which is also known as Boqueir��o de Parelhas/RN. This represents the spatial distribution of the phytoplankton species in order to understand any possible alterations of the water quality and the phytoplankton composition in relation to the water quality originating from the impact of the tilapia, Oreochromis niloticus, culture. The study period also encompasses temporal variations exhibited in two seasons of an annual cycle, one during the dry season (Oct, Nov and Dec of 2008 and Jan of 2009), and the other rainy season (Mar, Apr, May and June of 2008) to extend the observation. The physicalchemical parameters, such as pH, temperature, electrical conductivity, concentration of dissolved oxygen were measured in situ and the values of the inorganic nutrients (nitrate, ammonium and orto-phosfato) and chlorophyll in the laboratory. The quali-quantitative analyses of the phytoplankton had been carried through sedimentation technique and the enumeration of the random of 400 cells, colonies and filaments counted using Sedgwick-Rafter counting chamber. The results of pH varied widely from the acidic to alkaline range with the minimum of 5.8 (�� 0.8) and the maximum of 9.2 (�� 0.7-0.8), at point 1 and 2. The dissolved oxygen content was higher in the rainy period than that in the dry period. The maximum electrical conductivity was of 1409 ��Scm-1 in point 1 and 431 minim of ��Scm-1, in point 2. There was a considerable alteration in the levels of inorganic nutrients such as nitrate-nitrogen, ammoniacal nitrogen and orthophosphate during the two cycles of study period. Phytoplankton assemblages presented a picture of alternate dominance among species Cyanobacteria, Bacillariophyceae and Chlorophyceae. The trophic state index diagnosed to the category of mesotrophic, which is based on the values of chlorophyll, total phosphorus and Secchi-disc measurements. The wind driven turbulence of the water column and the fresh inflow of water (flushing and dilution) during rainy season acted as constraint and did-not allow an exaggerated growth of the species of cyanobacteria. On the basis of the present we conclude that the culture of tilapias in cage-culture fails to produce pollution load that could compromise the quality of the water of the dam, probably be due to small dimension of the culture in relation to the size, volume of the water and the reservoir capacity support its own environment

La participation en amont de grands projets d'am��nagement : les effets sur le projet et ses acteurs.

Depuis plus de trente ans, nos pratiques d��mocratiques ��voluent au rythme de liens grandissants entre les instances d��cisionnelles et la soci��t�� civile. Les exemples de d��marches participatives s���accumulent et leurs formes sont de plus en plus diverses. Au cours des derni��res ann��es, les d��marches en amont sont de plus en plus pr��sentes dans le paysage participatif et les organisations sont plus nombreuses que jamais �� faire le pari de l���amont. C���est le cas d���Hydro-Qu��bec avec ses les tables d���information et d�����change (TIE). Ces tables, existantes depuis la fin des ann��es 1990 et dirig��es par le ma��tre d���ouvrage, regroupent plusieurs acteurs du milieu. Elles se tiennent d��s le d��but du processus de planification. L���Office de consultation publique de Montr��al (OCPM) a elle aussi faut le saut en amont en adaptant ses m��thodes pour intervenir plus t��t dans le processus pour certains mandats. �� travers deux ��tudes de cas, une portant sur les TIE du complexe hydro��lectrique de la Romaine, et l���autre sur la consultation de l���OCPM sur la planification d��taill��e du secteur de Griffintown, ce m��moire explore les effets de la participation en amont sur les projets et sur ces acteurs.

SLOPE STABILITY ANALYSIS OF MOUNT MEAGER, SOUTH-WESTERN BRITISH COLUMBIA, CANADA

The Mount Meager Volcanic Complex (MMVC) in south-western British Columbia is a potentially active, hydrothermally altered massif comprising a series of steep, glaciated peaks. Climatic conditions and glacial retreat has led to the further weathering, exposure and de-buttressing of steep slopes composed of weak, unconsolidated material. This has resulted in an increased frequency of landslide events over the past few decades, many of which have dammed the rivers bordering the Complex. The breach of these debris dams presents a risk of flooding to the downstream communities. Preliminary mapping showed there are numerous sites around the Complex where future failure could occur. Some of these areas are currently undergoing progressive slope movement and display features to support this such as anti-scarps and tension cracks. The effect of water infiltration on stability was modelled using the Rocscience program Slide 6.0. The main site of focus was Mount Meager in the south- east of the Complex where the most recent landslide took place. Two profiles through Mount Meager were analysed along with one other location in the northern section of the MMVC, where instability had been detected. The lowest Factor of Safety (FOS) for each profile was displayed and an estimate of the volume which could be generated was deduced. A hazard map showing the inundation zones for various volumes of debris flows was created from simulations using LAHARZ. Results showed the massif is unstable, even before infiltration. Varying the amount of infiltration appears to have no significant impact on the FOS annually implying that small changes of any kind could also trigger failure. Further modelling could be done to assess the impact of infiltration over shorter time scales. The Slide models show the volume of material that could be delivered to the Lillooet River Valley to be of the order of 109 m3 which, based on the LAHARZ simulations, would completely inundate the valley and communities downstream. A major hazard of this is that the removal of such a large amount of material has the potential to trigger an explosive eruption of the geothermal system and renew volcanic activity. Although events of this size are infrequent, there is a significant risk to the communities downstream of the complex.

Waterpower : a geophysical and archaeological investigation of the waterpower system at the West Point Foundry, Cold Spring, New York

Waterpower: A Geophysical and Archaeological Investigation of the Waterpower System at the West Point Foundry, Cold Spring, New York, describes the results of ground penetrating radar surveys and archaeological excavation undertaken by Michigan Technological University (MTU) archaeologists during the summer of 2003 at the West Point Foundry, Cold Spring, New York. 2003 constituted MTU's second field season at the foundry. Fieldwork concentrated on the foundry's waterpower system, an intricate network of surface and subsurface drains, races, flumes, waterwheels, turbines, dams, and ponds that powered operations and regulated water flow throughout the site. Archaeologists utilized non-destructive geophysical technology, which expedited survey, facilitated placement of excavation units, and provided a model for future archaeogeophysical research at industrial sites. Features discovered during excavation provided valuable information pertaining to the waterpower system's construction and its functions. Data from ground penetrating radar surveys, archaeological excavation, historical photographs, documents, and maps permitted the development of a provisional chronology of the development of various components of the West Point Foundry's waterpower system. Information gathered during this project serves as an aid in sit interpretation and rehabilitation.

La participation en amont de grands projets d'am��nagement : les effets sur le projet et ses acteurs

Depuis plus de trente ans, nos pratiques d��mocratiques ��voluent au rythme de liens grandissants entre les instances d��cisionnelles et la soci��t�� civile. Les exemples de d��marches participatives s���accumulent et leurs formes sont de plus en plus diverses. Au cours des derni��res ann��es, les d��marches en amont sont de plus en plus pr��sentes dans le paysage participatif et les organisations sont plus nombreuses que jamais �� faire le pari de l���amont. C���est le cas d���Hydro-Qu��bec avec ses les tables d���information et d�����change (TIE). Ces tables, existantes depuis la fin des ann��es 1990 et dirig��es par le ma��tre d���ouvrage, regroupent plusieurs acteurs du milieu. Elles se tiennent d��s le d��but du processus de planification. L���Office de consultation publique de Montr��al (OCPM) a elle aussi faut le saut en amont en adaptant ses m��thodes pour intervenir plus t��t dans le processus pour certains mandats. �� travers deux ��tudes de cas, une portant sur les TIE du complexe hydro��lectrique de la Romaine, et l���autre sur la consultation de l���OCPM sur la planification d��taill��e du secteur de Griffintown, ce m��moire explore les effets de la participation en amont sur les projets et sur ces acteurs.

Progesterone attenuates microglial-driven retinal degeneration and stimulates protective Fractalkine-CX3CR1 signaling

Retinitis pigmentosa (RP) is a degenerative disease leading to photoreceptor cell loss. Mouse models of RP, such as the rd10 mouse (B6.CXBl-Pde6brd10/J), have enhanced our understanding of the disease, allowing for development of potential therapeutics. In 2011, our group first demonstrated that the synthetic progesterone analogue ���Norgestrel��� is neuroprotective in two mouse models of retinal degeneration, including the rd10 mouse. We have since elucidated several mechanisms by which Norgestrel protects stressed photoreceptors, such as upregulating growth factors. This study consequently aimed to further characterize Norgestrel���s neuroprotective effects. Specifically, we sought to investigate the role that microglia might play; for microglial-derived inflammation has been shown to potentiate neurodegeneration. Dams of post-natal day (P) 10 rd10 pups were given a Norgestrel-supplemented diet (80mg/kg). Upon weaning, pups remained on Norgestrel. Tissue was harvested from P15-P50 rd10 mice on control or Norgestrel-supplemented diet. Norgestrel-diet administration provided significant retinal protection out to P40 in rd10 mice. Alterations in microglial activity coincided with significant protection, implicating microglial changes in Norgestrel-induced neuroprotection. Utilizing primary cultures of retinal microglia and 661W photoreceptor-like cells, we show that rd10 microglia drive neuronal cell death. We reveal a novel role of Norgestrel, acting directly on microglia to reduce pro-inflammatory activation and prevent neuronal cell death. Norgestrel effectively suppresses cytokine, chemokine and danger-associated molecular pattern molecule (DAMP) expression in the rd10 retina. Remarkably, Norgestrel upregulates fractalkine-CX3CR1 signaling 1 000-fold at the RNA level, in the rd10 mouse. Fractalkine-CX3CR1 signaling has been shown to protect neurons by regulating retinal microglial activation and migration. Ultimately, these results present Norgestrel as a promising treatment for RP, with dual actions as a neuroprotective and anti-inflammatory agent in the retina.

Effects of gestational and postnatal exposure to chronic intermittent hypoxia on diaphragm muscle contractile function in the rat

Alterations to the supply of oxygen during early life presents a profound stressor to physiological systems with aberrant remodeling that is often long-lasting. Chronic intermittent hypoxia (CIH) is a feature of apnea of prematurity, chronic lung disease, and sleep apnea. CIH affects respiratory control but there is a dearth of information concerning the effects of CIH on respiratory muscles, including the diaphragm���the major pump muscle of breathing. We investigated the effects of exposure to gestational CIH (gCIH) and postnatal CIH (pCIH) on diaphragm muscle function in male and female rats. CIH consisted of exposure in environmental chambers to 90 s of hypoxia reaching 5% O2 at nadir, once every 5 min, 8 h a day. Exposure to gCIH started within 24 h of identification of a copulation plug and continued until day 20 of gestation; animals were studied on postnatal day 22 or 42. For pCIH, pups were born in normoxia and within 24 h of delivery were exposed with dams to CIH for 3 weeks; animals were studied on postnatal day 22 or 42. Sham groups were exposed to normoxia in parallel. Following gas exposures, diaphragm muscle contractile, and endurance properties were examined ex vivo. Neither gCIH nor pCIH exposure had effects on diaphragm muscle force-generating capacity or endurance in either sex. Similarly, early life exposure to CIH did not affect muscle tolerance of severe hypoxic stress determined ex vivo. The findings contrast with our recent observation of upper airway dilator muscle weakness following exposure to pCIH. Thus, the present study suggests a relative resilience to hypoxic stress in diaphragm muscle. Co-ordinated activity of thoracic pump and upper airway dilator muscles is required for optimal control of upper airway caliber. A mismatch in the force-generating capacity of the complementary muscle groups could have adverse consequences for the control of airway patency and respiratory homeostasis.

Early life exposure to chronic intermittent hypoxia primes increased susceptibility to hypoxia-induced weakness in rat sternohyoid muscle during adulthood

Intermittent hypoxia is a feature of apnea of prematurity (AOP), chronic lung disease, and sleep apnea. Despite the clinical relevance, the long-term effects of hypoxic exposure in early life on respiratory control are not well defined. We recently reported that exposure to chronic intermittent hypoxia (CIH) during postnatal development (pCIH) causes upper airway muscle weakness in both sexes, which persists for several weeks. We sought to examine if there are persistent sex-dependent effects of pCIH on respiratory muscle function into adulthood and/or increased susceptibility to re-exposure to CIH in adulthood in animals previously exposed to CIH during postnatal development. We hypothesized that pCIH would cause long-lasting muscle impairment and increased susceptibility to subsequent hypoxia. Within 24 h of delivery, pups and their respective dams were exposed to CIH: 90 s of hypoxia reaching 5% O2 at nadir; once every 5 min, 8 h per day for 3 weeks. Sham groups were exposed to normoxia in parallel. Three groups were studied: sham; pCIH; and pCIH combined with adult CIH (p+aCIH), where a subset of the pCIH-exposed pups were re-exposed to the same CIH paradigm beginning at 13 weeks. Following gas exposures, sternohyoid and diaphragm muscle isometric contractile and endurance properties were examined ex vivo. There was no apparent lasting effect of pCIH on respiratory muscle function in adults. However, in both males and females, re-exposure to CIH in adulthood in pCIH-exposed animals caused sternohyoid (but not diaphragm) weakness. Exposure to this paradigm of CIH in adulthood alone had no effect on muscle function. Persistent susceptibility in pCIH-exposed airway dilator muscle to subsequent hypoxic insult may have implications for the control of airway patency in adult humans exposed to intermittent hypoxic stress during early life.

Atlantic salmon in regulated rivers : Migration, dam passage, and fish behavior

Hydropower dams block migration routes and disrupt longitudinal connectivity in rivers, thereby posing a threat to migratory fish species. Various fish passage solutions have been implemented to improve connectivity with varying success. A well-functioning passage solution must ensure safe and timely passage routes that are used by a substantial portion of the migrating fish. In this thesis, I report the results from telemetry studies where the behavior and survival of migrating Atlantic salmon spawners, post-spawners and smolts have been evaluated in relation to hydropower dam passage. I evaluate downstream passage performance at dams with no passage solutions in the River Klar��lven, and with simple passage solutions in in the Winooski River. In the River ��tran, I study both upstream- and downstream passage performance at a dam with sophisticated passage solutions based on the best available technology. In addition, I have studied the survival and behavior of post-spawners and hatchery-released smolts. A substantial portion of the spawners survived spawning and initiated downstream migration. Most males migrated downstream in autumn following spawning, whereas females tended to stay in the river until spring. For hatchery-reared smolts, early release was associated with faster initiation of migration and higher survival compared to late release. Multiple dam passage resulted in high mortality for both smolts and kelts. For smolts, dam passage, even with simple passage solutions, was associated with substantial delay and mortality. High spill levels were linked to high survival and short delay for downstream migrating salmon. The best available passage solution, which consisted of a nature-like fishway and a low sloping intake rack to guide fish to a bypass, resulted in rapid passage of a large portion of the adult migrants.

Progress

The Savannah Valley Authority publishes this quarterly newsletter giving an update on various projects, meetings and developments going on in the Savannah Valley Region. This issue covers among other things, Savannah Lakes Village, Lake Russell Project, utility planning and lake levels.

Solastalgia y conductas pro-ambientales en un conflicto socioambiental por la construcci��n de una hidroel��ctrica

Introducci��n: La construcci��n de megaproyectos h��dricos implica una reconfiguraci��n territorial donde se ven afectadas las fuentes de agua dulce, la biodiversidad terrestre y acu��tica, y los asentamientos humanos que colindan con dichas construcciones. Objetivo: estimar la asociaci��n entre las conductas proambientales con la solastalgia entre las personas que se encuentran ejerciendo un proceso de resistencia social contra la Central Hidrosogamoso en el departamento de Santander, Colombia. Metodolog��a: se utiliz�� un dise��o de estudio transversal en el que se entrevistaron integrantes y no integrantes de grupos ambientalistas de las zonas de influencia del proyecto. Se realiz�� un an��lisis descriptivo de las variables sociodemogr��ficas de los dos grupos de comparaci��n presentando frecuencias absolutas y relativas y diferencias significativas por medio de la prueba ji cuadrado, exacta de Fisher y U de Mann Whitney. Se utiliz�� un modelo de regresi��n lineal m��ltiple en el que la variable dependiente fue el puntaje de solastalgia y las variables independientes fueron las escalas de las conductas proambientales: altruismo, austeridad, equidad, conducta ecol��gica, deliberaci��n, indignaci��n y aprecio por lo natural, adem��s, se ajust�� por algunas variables sociodemogr��ficas de inter��s. Resultados: los grupos comparados presentaron diferencias importantes en cuanto a la zona de procedencia, condiciones econ��micas y organizaci��n social. El incremento de 5 puntos en la escala del sentimiento de indignaci��n increment�� 0.98 la escala de solastalgia (IC95%: 0.19; 1.78). Las personas sin pareja estable tuvieron 3.02 puntos menos de solastalgia comparadas con personas casadas o en uni��n libre (IC95%: -4.96; -1.44), mientras que aquellas con alto nivel educativo obtuvieron 2.02 puntos menos que las personas con primaria y bachillerato (IC95%: -3.99; -0.06). Un modelo alterno mostr�� que no pertenecer a un grupo ambientalista disminuye en 2.29 puntos la solastalgia, comparado con pertenecer a un grupo (IC95%: -4.31; -0.28),. Conclusi��n: posiblemente las motivaciones por las cuales los actores involucrados se resisten a las transformaciones territoriales ocasionadas por la construcci��n de las represas son m��s un reflejo de la condici��n socioecon��mica que de la preocupaci��n de los actores por el da��o del medio ambiente y adem��s, esta resistencia es un fen��meno que se limita a aquellos que est��n afectados directamente en el ��rea de influencia del proyecto

Effects of flow regulation in the life-cycles of a mediterranean cyprinid species, the Iberian chub (Squalius carolitertii Doadrio, 1987)

Streamflow is considered a driver of inter and intra���specific life���history differences among freshwater fish. Therefore, dams and related flow regulation, can have deleterious impacts on their life���cycles. The main objective of this study is to assess the effects of flow regulation on the growth and reproduction of a non���migratory fish species. During one year, samples were collected from two populations of Iberian chub, inhabiting rivers with non���regulated and regulated flow regimes. Flow regulation for water derivation promoted changes in chub���s condition, duration of gonad maturation and spawning, fecundity and oocyte size. However, this non���migratory species was less responsive to streamflow regulation than a migratory species analysed. Findings from this study are important to understand changes imposed by regulated rivers on fish and can be used as guidelines for flow requirements implementations; RESUMO: O caudal �� um dos fatores respons��veis pelo funcionamento dos ciclos de vida das esp��cies pisc��colas dulciaqu��colas. As barragens, e a regulariza����o de caudal associada, podem ter impactes nos ciclos de vida destas esp��cies. O objetivo deste estudo prende���se com a avalia����o dos efeitos da regulariza����o de caudal no crescimento e reprodu����o de uma esp��cie pisc��cola n��o���migradora. A an��lise de amostras recolhidas em popula����es de escalo do Norte provenientes de dois rios de caudal regularizado e n��o regularizado, identificaram impactes significativos a n��vel da condi����o corporal, da matura����o das g��nadas e desova, da fecundidade e da dimens��o dos o��citos. Esta esp��cie n��o���migradora parece ser menos responsiva �� artificializa����o do caudal que uma esp��cie migradora previamente analisada. Estes resultados permitem compreender as altera����es impostas pela regulariza����o do caudal e podem ser usados em programas de reabilita����o fluvial.

El proyecto hidroel��ctrico del Arenal y el impacto en su entorno econ��mico y social 1950-1994

Resumen Analiza el impacto que tuvo la construcci��n del proyecto hidroel��ctrico del Arenal y con base en historia oral recuperar la opini��n de los campesinos cuyas tierras fueron inundadas por el embalse. Abstract The author analyzes the impact of the construction of the Arenal hydroelectric project, and uses oral history to uncover the opinion of those peasants whose lands were flooded by the dam��s construction.

Reproductive and developmental toxicity study using Sprague-Dawley rats exposed under various calendars to the weedkiller Glyphosate and commercial formulations Glyphosate-based

Glyphosate-based herbicides (GBHs) are the most globally used herbicides raising the risk of environmental exposition. Carcinogenic effects are only one component of the multiple adverse health effects of Glyphosate and GBHs that have been reported. Questions related to hazards and corresponding risks identified in relation to endocrine disrupting effects are rising. The present study investigated the possible reproductive/developmental toxicity of GBHs administered to male and female Sprague-Dawley rats under various calendar of treatment. Assessments included maternal and reproductive outcome of F0 and F1 dams exposed to GBHs throughout pregnancy and lactation and developmental landmarks and sexual characteristics of offspring. The study was designed in two stages. In the first stage Glyphosate, or its commercial formulation Roundup Bioflow, was administered to rats at the dose of 1.75 mg/kg bw/day (Glyphosate US Acceptable Daily Intake) from the prenatal period until adulthood. In the second stage, multiple toxicological parameters were simultaneously assessed, including multigeneration reproductive/developmental toxicity of Glyphosate and two GBHs (Roundup Bioflow and Ranger Pro). Man-equivalent doses, beginning from 0.5 mg/kg bw/day (ADI Europe) up to 50 mg/kg bw/day (NOAEL Glyphosate), were administered to male and female rats, covering specific windows of biological susceptibility. The results of stage 1 and preliminary data from stage 2 experiments characterize GBHs as probable endocrine disruptors as suggested by: 1) androgen-like effects of Roundup Bioflow, including a significant increase of anogenital distances in both males and females, delay of first estrous and increased testosterone in females; 2) slight puberty onset anticipation in the high dose of Ranger Pro group, observed in the F1 generation treated from in utero life until adulthood; 3) a delayed balano-preputial separation achievement in the high dose of Ranger Pro-treated males exposed only during the peri-pubertal period, indicating a direct and specific effect of GBHs depending on the timing of exposure.

Seismotectonic study on two strategic infrastructures in Southern Italy

With the entry into force of the latest Italian Building Code (NTC 2008, 2018), innovative criteria were provided, especially for what concerns the seismic verifications of large infrastructures. In particular, for buildings considered as strategic, such as large dams, a seismotectonic study of the site was declared necessary, which involves a re-assessment of the basic seismic hazard. This PhD project fits into this context, being part of the seismic re-evaluation process of large dams launched on a national scale following the O.P.C.M. 3274/2003, D.L. 79/2004. A full seismotectonic study in the region of two large earth dams in Southern Italy was carried out. We identified and characterized the structures that could generate earthquakes in our study area, together with the definition of the local seismic history. This information was used for the reassessment of the basic seismic hazard, using probabilistic seismic hazard assessment approaches. In recent years, fault-based models for the seismic hazard assessment have been proposed all over the world as a new emerging methodology. For this reason, we decided to test the innovative SHERIFS approach on our study area. The occasion of the seismotectonic study gave also the opportunity to focus on the characteristics of the seismic stations that provided the data for the study itself. In the context of the work presented here, we focused on the 10 stations that had been active for the longest time and we carried out a geophysical characterization, the data of which merged into a more general study on the soil-structure interaction at seismic stations and on the ways in which it could affect the SHA. Lastly, an additional experimental study on the two dams and their associated minor structures is also presented, aimed at defining their main dynamic parameters, useful for subsequent dynamic structural and geotechnical studies.