Studies on the Dynamics of Cochin Estuary

The thesis entitled Studies on the Dynamics of Cochin Estuary. This thesis is addressed to an investigation on the tidal, seasonal and spatial variations of the hydrographic parameters, circulation and mixing processes of the Cochin estuary. The present programme of study is aimed at obtaining a comprehensive picture of the tidal characteristics, hydrography, circulation and mixing present in this estuarine system during different seasons. The studies have been carried out through field collection of data on salinity, temperature and water currents to get a picture of their spatial and temporal variations. The hydrographic data have been analysed in relation to tide, rainfall and river discharges. From the findings it is seen that at the Cochin inlet, the estuarine features vary annually. During July and August, the estuary is characterised as almost saltwedge type; during June, September, October, December and January it shows appreciabie stratification, and during the rest of the months the estuary shows almost well mixed nature. Seasonal variations are well reflected in water temperature in the Cochin estuary, where the temperature reaches its maximum during the dry pre monsoon period with very weak thermal gradients indicating strong vertical mixing

Studies on the ecology of zooplankton of cochin backwaters(a tropical estuary)

Ecology is the study of systems at a level in which individuals or whole organisms may be considered elements of interaction, either among themselves, or with a loosely organised environmental matrix. Systems at this level are named ecosystems, and ecology, of course, is the biology of ecosystems" (Hargalef, 1968). This thesis includes principally, a study on the ecology of zooplankton of the Cochin backwaters conducted during the years 1971-72. This monsoonal estuarine system is particularly interesting, since it exhibits a wide range of variations in its environmental conditions which is naturally reflected in the fauna also. Several publications on various aspects of its hydrobiology have come out in the recent past. But studies on the zooplankton of the estuary have mostly been discontinuous either in space or time or restricted to its groups

Development of Zero Water Exchange Shrimp Culture System Integrated With Bioremediation of Detritus and Ammonia- Nitrogen

Aquaculture is one of the fastest growing food sectors in the world. Amongst the various branches of aquaculture, shrimp culture has expanded rapidly across the globe because of its faster growth rate, short culture period, high export value and demand in the International market. Indian shrimp farming has experienced phenomenal development over the decades due to its excellent commercial viability. Farmers have adopted a number of innovative technologies to improve the production and to maximize the returns per unit area. The culture methods adopted can be classified in to extensive, modified extensive and semi intensive based on the management strategies adopted in terms of pond size, stocking density, feeding and environmental control. In all these systems water exchanges through the natural tidal effects, or pump fed either from creek or from estuaries is a common practice. In all the cases, the systems are prone to epizootics due to the pathogen introduction through the incoming water, either brought by vectors, reservoir hosts, infected tissue debris and free pathogens themselves. In this scenario, measures to prevent the introduction of pathogen have become a necessity to protect the crop from the onslaught of diseases as well as to prevent the discharge of waste water in to the culture environment.The present thesis deals with Standardization of bioremediation technology for zero water exchange shrimp culture system

studies on Prawn Gill Nets of The Kerala Coast

In the present study. extensive investigations were carried out on various factors affecting the selectivity of prawn gill nets with reference to material, mesh size, coefficient of hanging secolouration. Effect of tidal current on fishing height of prawn gill net and seasonal variation of catch during the course of these investigations were also studied.

Studies on sphaeroma terebrans bate of the port of Cochi

Sphaeroma terebrans Bate, one of the most destructive wood-boring isopod crustacean occurring in the Cochin harbour region was taken up for investigations on its habitat, breeding, attack on timber, salinity tolerance and respiration. The respiration of the animal under different stresses was noted using an instrument fabricated in the laboratory. Of the various hydrographic conditions of the Cochin harbour region studied, salinity is found to be the most fluctuating factor and the variations are largely influenced by the seasonal rain fall from one side and the tidal currents on the other.In spite of the great fluctuations in salinity, Sphaeroma terebrans occurs throughout the year in the Cochin harbour region, though their number varies in different months. Exposure tests show that Sphaeroma terebrans can remain for about 20 to 24 hours outside water in a damp atmosphere.

Assessment of Water Quality along the Coastal Areas of Kerala: A Study of the Tsunami Impact on Groundwater

Everywhere, on the coastal belt it is proved without doubt that the pristine ground water quality was severely deteriorated after the 26 December 2004 Indian Ocean Tsunami. But how far is more relevant, as it is decided by the so-called pre-tsunamic situation of the region. In water quality studies it is this reference finger print which earmarks regional ground water chemistry based on which the monthly variability could rationally be interpreted. This Ph D thesis comprises the testing and evaluation of the facts: whether there is any significant difference in the water quality parameters under study between stations and between months in Tsunami Affected Dug Wells (TADW). Whether the selected water quality parameters vary significantly from BIS and WHO standards. Whether the water quality index (WQI) differ significantly between Tsunami Affected Dug Wells (TADW) and Bore Wells (BW). Whether there is any significant difference in the water quality parameters during December 2005 and December 2008. Is there any significant change in the Water Quality Parameters before 2001 and after tsunami (2005) in TADW.

Tide And River Runoff Interactions In The Cochin Estuary

Hydrodynamic characteristics of an estuary resulting from interaction of tide and river runoff are important since problems regarding flood, salinity intrusion, water quality, ecosystem and sedimentation are ubiquitous. The present study focuses on such hydrodynamic aspects in the Cochin estuary. Most of the estuaries that come under the influence of Indian Summer Monsoon and for which the salinity is never in a steady state at any time of the year are generally shallow and convergent, i.e. the width decreases rapidly from mouth to head. In contrast, Cochin estuary is wider towards the upstream and has no typical river mouth, where the rivers are joining the estuary along the length of its channel .Adding to the complexity it has dual inlets and the tidal range is 1 m which is lower than other Indian estuaries along west coast. These typical physical features lead to its unique hydrodynamic characteristics. Therefore the thesis objectives are: I) to study the influence of river runoff on tidal propagation using observations and a numerical model ii) to study stratification and property distributions in Cochin estuary iii) to understand salinity distributions and flushing characteristics iv) to understand the influence of saltwater barrage on tides and salinity v) To evaluate several classification schemes for the estuary

Studies On The Dynamics And Water Quality Of The Muvattupuzha River In Relation To Effluent Discharge

The present study aims at the investigation of the 1ysico—chemical features of a tropical tidal river viz. we Muvattupuzha river. This river is expected to receive Jderate to heavy pollution loads in years to come, from we lone industrial unit, already set up on its bank. ilike other rivers, the geographical disposition of this Lver attains unique importance as regards its dynamics for 3) availability of natural runoff water from catchment :eas, which becomes very heavy during the monsoon season 3) regular steady availability of tail race water from a /dro—electric power station throughout the yearThe study also aims at arriving at the balancing forces of inherent self~purification of the river verses pollution loads from the factory effluents. The investigation period falls ahead of actual pollution occurrence and so the ambient conditions for a period of nearly one-and-a—half years were investigated, the analyses of which providflz to formulate the inter-relations of parameters varying with seasons. Tracer experiments were carried out which revealed the dispersion and dilution characteristics of the river in the vicinity of effluent outfall. The studv covers the trial—cum-capacity production periods of the factory during which effluents of various strength and quantity were discharged into the river; a few computed values arQ’cjmpgrQdl ... with the observed values. The base data along with the profiles of Oxygen sag equation have been utilized fb develop a mathematical model of the river with regard to its water quality

Habitat ecology and food and feeding of the herring bow crab Varuna litterata (Fabricius, 1798) of Cochin backwaters, Kerala, India

Habitat ecology and food and feeding of the herring bow crab, Varuna litterata of Cochin Backwaters, Kerala, India were investigated for a period of one year (April 2011-March 2012). Among the 15 stations surveyed, the crabs were found to occur only in 4 stations, which had a close proximity to the sea. Sediment analysis of the stations revealed that the substratum of these stations is sandy in nature and is rich in organic carbon content (0.79% to 1.07%). These estuarine crabs is euryhaline and are found to be distributed in areas with a sandy substratum, higher organic carbon content and more tidal influx. The stomach contents analysis of crabs examined showed that their diet included crustacean remains, plants, sand and debris, fishes, miscellaneous group and unidentified matter. In adults and sub-adults, crustaceans formed the dominant food group, while in juveniles, sand and debris formed the dominant group. From the present study, V. litterata was found to be a predatory omnivore capable of ingesting both animal and plant tissues

Bioactive Metabolites and Biomarkers from Rhizophoraceae mangroves- A Chemotaxonomic Approach

Mangroves are specialised ecosystems developed along estuarine sea coasts and river mouths in tropical and subtropical regions of the world, mainly in the intertidal zone. Hence, the ecosystem and its biological components is under the influence of both marine and freshwater conditions and has developed a set of physiological adaptations to overcome problems of anoxia, salinity and frequent tidal inundations. This has led to the assemblage of a wide variety of plant and animal species of special adaptations suited to the ecosystem. The path of photosynthesis in mangroves is different from other glycophytes. There are modifications or alterations in other physiological processes such as carbohydrate metabolism or polyphenol synthesis. As they survive under extreme conditions of salinity, temperature, tides and anoxic soil conditions they may have chemical compounds, which protect them from these destructive elements. Mangroves are necessarily tolerant of high salt levels and have mechanisms to take up water despite strong osmotic potentials. Some also take up salts, but excrete them through specialised glands in the leaves. Others transfer salts into senescent leaves or store them in the bark or the wood. Still others simply become increasingly conservative in their water use as water salinity increases. A usual transportation or biosynthetic path as other plants cannot be expected in mangrove plants. In India, the states like West Bengal, Orissa, Andhra Pradesh, Tamil Nadu, Andaman and Nicobar Islands, Kerala, Goa, Maharashtra, and Gujarat occupy vast area of mangroves. Kerala has only 6 km2 total mangrove area with Rhizophora apiculata, Rhizophora mucronata, Bruguiera gymnorrhiza, Bruguiera cylindrica, Avicennia officinalis, Sonneratia caseolaris, Sonneratia apetala and Kandelia candal, as the important species present, most of which belong to the family Rhizophoraceae.Rhizophoraceae mangroves are ranked as “major elements of mangroves” as they give the real shape of this unique and interesting ecosystem and these mangrove species most productive and typical characteristic ecosystem of World renowned. It was found that the Rhizophoraceae mangrove extracts exhibit several bioactive properties. Various parts of these mangroves are used in ethnomedicinal practices. Even though extracts from these mangroves possess therapeutic activity against humans, animal and plant pathogens, the specific metabolites responsible for these bioactivities remains to be elucidated. Various parts of these mangroves are used in ethnomedicinal practices. There is a gap of information towards the chemistry of Rhizophoraceae mangroves from Kerala. Thorough phytochemical investigation can achieve the validity of ethnomedicines as well as apply the use of mangrove plants in the development of new drugs. Such studies can pave a firm base for their use in biomarker and chemotaxonomic studies as well as for the better management of the existing mangrove ecosystem. In this study, the various chemical parameters including minerals, biochemical components, bioactive and biomarker molecules were used to classify and assess the possible potentials of the mangrove plants of the true mangrove family Rhizophoraceae from Kochi.

Dispositivo de no reinhalación NRMASK, pruebas de eficacia, desempeño y seguridad

Objetivo del estudio: comparar las mediciones realizadas en el dispositivo de entrega de agente halogenado, con un modelo matemático donde se encontraron los valores ideales de fracción espirada de agente halogenado para cada evento. Diseño del estudio: diseño de tecnología. Lugar de desarrollo: salas de cirugía de un Hospital Universitario, Bogotá, Colombia. Intervenciones y medidas: luego de diseñar y ensamblar un circuito anestésico semiabierto tipo mascara facial con dos válvulas unidireccionales (una inspitratoria y otra espiratoria), se procedió a tomar las medidas de Concentración inspirada de sevofluorane, y fracción inspirada de oxigeno, con volúmenes espiratorios de 70 a 170 mL con intervalos de 10 mL, y con el dial de sevoflorane a 2, 2.2, 2.4, 2.6 vol%, los resultados consignados fueron comparados con los valores matemáticamente calculados para cada evento. Resultados: las mediciones realizadas en la máscara son concordantes con los cálculos realizados en el modelo matemático. La concentración espirada de sevoflorane es ligeramente superior en cada evento con respecto a lo encontrado en el modelo matemático, no es posible asegurar la no reinhalación con las mediciones realizadas.

Preoxigenacion con volumen corriente y capacidad vital en voluntarios sanos a 2600 metros

En la literatura existen descritas varias técnicas de preoxigenación aplicadas a diferentes pacientes y realizadas con diferentes flujos o fracciones inspiradas de oxigeno, sin embargo no se encuentran descripciones ni estudios realizados con respecto a este tópico en pacientes ubicados por encima de los 1000 mts sobre el nivel del mar. El objetivo del presente estudio es describir el patrón de saturación con oxigeno al 100% obteniendo fracción espirada de oxígeno (EtO2) >90% y Saturación de oxígeno (SaO2) > 99%, así como el patrón de normalización de la saturación de oxigeno con una fracción inspirada del 21% con cuatro técnicas estandarizadas de preoxigenación, en personas voluntarias sanas pertenecientes a la Fundación Cardio Infantil a 2600 metros sobre el nivel del mar. Materiales y métodos: Este es un estudio cuasiexperimental en personas adultas voluntarias sanas pertenecientes a la Fundación Cardio Infantil, los cuales son sometidos a toma de saturación de oxígeno basal y luego se les aplica preoxigenación con fracción inspirada oxigeno (FiO2) al 100% con un flujo de 10Lt/min, mediante sello de máscara facial con arnés: Simultáneamente se realiza una medición de la fracción espirada de oxígeno (ETO2) y oximetría de pulso (SaO2) cada 15 segundos con cada una de las cuatro pruebas de preoxigenación (volumen corriente por 3 minutos, 8 capacidades vitales, volumen corriente hasta ETO2 de =90% y capacidades vitales hasta ETO2 =90%) y luego medición del tiempo de normalización de la saturación respirando al oxígeno con FiO2 al 21 % hasta alcanzar nuevamente la SaO2 basal, con cada técnica. Resultados: No existe diferencia significativa en la aplicación de las técnicas de preoxigenación ni tampoco en el tiempo de normalización de la saturación de oxígeno con FiO2 al 21 % al nivel de Bogotá con las cuatro técnicas de preoxigenación aplicadas a nuestros pacientes. Conclusión: Las cuatro técnicas de preoxigenación son efectivas, sin embargo recomendamos el uso de técnicas que buscan una ETO2=90%. Por otra parte encontramos que el tiempo de recuperación de la saturación basal es de 3,9 minutos en personas voluntarias sanas a 2600 mts sobre el nivel del mar, la cual es inferior comparada con los 10 minutos que toma la normalización de la saturación de oxígeno a 0 mts sobre el nivel del mar descritos previamente en la literatura. Hace falta realizar estudios de preoxigenación y apnea en pacientes a nuestra altura (2600 mts sobre el nivel del mar) para confirmar que el tiempo de desaturación es significativamente menor que a nivel del mar. Palabras Claves: Preoxigenación, Fracción espirada de O2 (EtO2), saturación de oxígeno (SaO2).

Efectos de la ventilación mecánica con heliox en niños y adolescentes con patología bronquial obstructiva

Evaluar si el Heliox reduce la resistencia en la vía aérea en niños y adolescentes con patología bronquial obstructiva que requieren ventilación mecánica. Materiales y Métodos: Estudio prospectivo observacional descriptivo en niños y adolescentes con patología bronquial obstructiva y ventilación mecánica con Fi02 ≤ 0,5. Medición de variables: resistencia, presión pico, presión media de la vía aérea, presión meseta, volumen corriente, autoPEEP, distensibilidad, PetCO2, ventilación de espacio muerto antes de inicio de heliox y a los 30 minutos, 2, 4, 6, 12, 18 y 24 horas y diariamente hasta suspenderlo por extubación o FiO2 > 0,5. Resultados: Resultados parciales, incluyó 9 pacientes encontrando descenso significativo de resistencia espiratoria a los 30 minutos (51,2 vs 32,3; p=0,0008 ), 2 horas ( 51,2 vs 33,4; p=0,0019) y 4 horas (51,2 vs 30,7; p=0,0012) así como de la resistencia inspiratoria a la hora 2 (48,6 vs 36,2; p = 0,013) y hora 4 (48,6 vs 30 ; p=0,004). Se observó tendencia al descenso de la PetCO2 que no fue significativa (52,3 vs 34,3: p=0,06). No se evidenció cambios en las variables; autoPEEP, presión pico, presión media de la vía aérea, distensibilidad, ventilación de espacio muerto, presión meseta y volumen corriente antes y después del inicio del Heliox. Conclusión: La ventilación mecánica con Heliox en niños con patología bronquial obstructiva parece ser que reduce de manera significativa la resistencia de la vía aérea, con tendencia al descenso de la PetC02. Se necesitan estudios prospectivos al menos observacionales analíticos que corroboren estos hallazgos.

La Presión Intra-abdominal Influye Sobre los Limites de la Presión de la Vía Aérea Durante la Ventilación Protectora Pulmonar

Background: The Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) have a impact on the respiratory system and the recommendations for mechanical ventilation of patients with IAH/ACS remain unclear. Our study characterize the influence of elevated intra-abdominal pressure (IAP) and positive end-expiratory pressure (PEEP) on airway plateau pressure (PPLAT) and bladder pressure (PBLAD). Methods: Nine (n=9) deeply anesthetized swine were mechanically ventilated via tracheostomy: volume-controlled mode at tidal volume = 10 ml/kg, frequency=15, Inspiratory:Expiratory ratio=1:2 and PEEP of 1 and 10 cmH2O (PEEP1 and PEEP10, respectively). A tracheostomy tube was place in the peritoneal cavity and different levels of IAP were applied utilizing a CPAP system. Measurements were performed during both PEEP1 and PEEP10. Results: PBLAD increased as experimental IAP rose. Minimal underestimation of IAP by PBLAD was observed. Applying PEEP10 did not significantly affect the correlation between experimental IAP and PBLAD. PBLAD (in cmH2O) was reflected by changes in PPLAT regardless of the PEEP.

Caracterización de los pacientes críticos ventilados en la Fundación Santa Fe de Bogotá 2009 a 2013

Objetivo: Caracterizar a los pacientes que recibieron ventilación mecánica en las unidades de cuidado intensivo (UCI) de la Fundación Santa Fe de Bogotá entre los años 2009 y 2013. Metodología: Se analizó una cohorte retrospectiva de los pacientes en UCI que requirieron soporte ventilatorio mecánico al ingreso a la unidad independientemente de la causa. Resultados: La media de edad de los pacientes fue 63,83 años; el diagnóstico más frecuente de ingreso fue revascularización miocárdica, seguido por neumonía y recambio valvular aórtico; en el 43% de los casos la causa de la falla fue el estado postoperatorio. Los modos ventilatorios más frecuentemente utilizados fueron SIMV (27,5%) y ventilación asistida controlada (26,12%). El 50% de los pacientes fueron ventilados con PEEP < 6 cmH2O. La mortalidad bruta fue del 15%. 22% de los pacientes tuvieron estancia prolongada en UCI. Se aplicó protocolo de retiro de ventilación mecánica en el 77% de los pacientes. La duración de la ventilación mecánica es mayor a medida que aumenta la edad del paciente entre los 60 y los 80 años. La mortalidad es cercana al 50% alrededor de los 50 años y mayor a 80% después de los 80 años. El soporte ventilatorio por cinco o más días aumentó la mortalidad a 80% o más. Discusión y Conclusiones: Estos resultados son comparables a los encontrados en estudios previos. Este estudio puede ser considerado como el primer paso para generar un registro adecuado de la ventilación de la mecánica de las unidades de cuidado intensivo del país.