Development and collapse of an Oscillatoria bloom in Loch Leven during July 1994

During 1994, weekly spot-sampling of open water sites on Loch Leven took place from 16th March onwards. Very little difference between spot-sampling sites was observed from 16th March to 5th July. Throughout April and May there was a slow increase in levels of chlorophyll-a, followed by a rapid increase through June, reaching a maximum of 230 micrograms per litre. On 8th July there was a very rapid rise in water temperature, with a corresponding increase in dissolved oxygen and pH. At 0915 hours on 9th July there was a drop in all three variables. These changes were coincident with a marked reduction in chlorophyll-a values falling to 70 micrograms per litre on 12th July. On 16th July evidence of a resurgence of photosynthesis was observed.

Development and Application of Embedding Methods for the Simulation of Large Chemical Systems

The high computational cost of correlated wavefunction theory (WFT) calculations has motivated the development of numerous methods to partition the description of large chemical systems into smaller subsystem calculations. For example, WFT-in-DFT embedding methods facilitate the partitioning of a system into two subsystems: a subsystem A that is treated using an accurate WFT method, and a subsystem B that is treated using a more efficient Kohn-Sham density functional theory (KS-DFT) method. Representation of the interactions between subsystems is non-trivial, and often requires the use of approximate kinetic energy functionals or computationally challenging optimized effective potential calculations; however, it has recently been shown that these challenges can be eliminated through the use of a projection operator. This dissertation describes the development and application of embedding methods that enable accurate and efficient calculation of the properties of large chemical systems.

Chapter 1 introduces a method for efficiently performing projection-based WFT-in-DFT embedding calculations on large systems. This is accomplished by using a truncated basis set representation of the subsystem A wavefunction. We show that naive truncation of the basis set associated with subsystem A can lead to large numerical artifacts, and present an approach for systematically controlling these artifacts.

Chapter 2 describes the application of the projection-based embedding method to investigate the oxidative stability of lithium-ion batteries. We study the oxidation potentials of mixtures of ethylene carbonate (EC) and dimethyl carbonate (DMC) by using the projection-based embedding method to calculate the vertical ionization energy (IE) of individual molecules at the CCSD(T) level of theory, while explicitly accounting for the solvent using DFT. Interestingly, we reveal that large contributions to the solvation properties of DMC originate from quadrupolar interactions, resulting in a much larger solvent reorganization energy than that predicted using simple dielectric continuum models. Demonstration that the solvation properties of EC and DMC are governed by fundamentally different intermolecular interactions provides insight into key aspects of lithium-ion batteries, with relevance to electrolyte decomposition processes, solid-electrolyte interphase formation, and the local solvation environment of lithium cations.

Observations on the influence of external factors on the duration of the embryonic development and on the molting rhythm of Cyclops vicinus. [Translation from: Oecologia 7, 342-355, 1971.]

Investigations on the control of the embryonic and post-embryonic development of arthropods have formed an intensively studied field of zoological research for a long time, Here in especially favourable cases the causal chain from the operation of external factors on the influence of physiological mechanisms, eg. of the hormone variety, is known right through to its primary influences. A comparative approach to the relevant questions was in the main only made in the case of the insects. For crustacea , investigations are available almost exclusively only for the malacostraca. This study examines the influence of the factors of temperature and photoperiod on the entire development of Cyclops vicinus. Tests were made on whether the light-darkness change serves as a regulator for a possible existing molting rhythm - a question which for the entire arthropods has been settled only very rarely. The basic material for the cultures that were examined originates from Lake Constance.

Aspects of the washout of salmonid eggs. 2. Effects of drifting on development and survival of eggs of brown trout (Salmo trutta L.)

At high stream discharges salmonid eggs can he displaced from the gravel and may drift downstream. It has been suggested that developing salmonid eggs may be killed by ”physical shock”, especially during the period before ”eyeing”. Similarly, a progress report by the International Pacific Salmon Fisheries Commission (1966) states that salmonid eggs are most sensitive during the period between fertilisation and blastopore closure. However, it would seem unlikely that this sensitivity actually begins at the time of fertilisation because, in nature, a period, perhaps measured in hours, must occur during which the newly-fertilised eggs are exposed to physical shock during the deposition of gravel over them as a result of the cutting activity of the female fish. The present report describes simple channel experiments designed to answer the two questions: 1. After release of eggs from the gravel, does the process of drifting downstream, which implies some physical shock through movement and impact, decrease the survival of salmonid eggs? 2. Is the survival rate-influenced by the stage of development of the eggs?

DEVELOPMENT AND APPLICATIONS OF TIME-DEPENDENT DENSITY MATRIX FUNCTIONAL THEORY

En esta tesis estudiamos las teorías sobre la Matriz Densidad Reducida (MDR) como un marco prometedor. Nos enfocamos sobre esta teorías desde dos aspectos: Primero, usamos algunos modelos sencillos hechos con dos partículas las cuales estan armónicamente confinadas como una base para ilustrar la utilidad de la matriz densidad. Para tales sistemas, usamos la MDR de un cuerpo para calcular algunas cantidades de interés tales como densidad de momentum. Posteriormente obtenemos los orbitales naturales y su número de ocupación para algunos de los modelos, y en uno de los casos expresamos la MDR de dos cuerpos de manera exacta en términos de la MDR de un cuerpo. También usamos el teorema diferencial del virial para establecer una descripción unificada de la familia entera de estos sistemas modelo en términos de la densidad. En la seguna parte cambiamos a casos fuera del equilibrio y analizamos la así llamada jerarquía BBGKY de ecuaciones para describir la evolución temporal de un sistema de muchos cuerpos en términos de sus MDRs (a todos los órdenes). Proveemos un exhaustivo estudio de los desafíos y problemas abiertos ligados a la truncación de tales jerarquías de ecuaciones para hacerlas aplicables. Restringimos nuestro análisis a la evolución acoplada de la MDR de uno y dos cuerpos, donde los efectos de correlación de alto orden estan embebidos dentro de la aproximación usada para cerrar las ecuaciones. Probamos que dentro de esta aproximación, el número de electrones y la energía total se conservan, sin importar la aproximación usada. Luego, demostramos que aplicando los esquemas de truncación de estado base para llevar los electrones a comportamientos indeseables y no físicos, tales como la violación e incluso la divergencia en la densidad electrónica local, tanto en regímenes correlacionados débiles y fuertes.

Exploring new labelling strategies for boronated compounds: towards fast development and efficient assessment of BNCT drug candidates

208 p.

The effect of organotin and copper sulfate on the late development and presettlement behavior of the hard clam Mercenaria mercenaria

The effect of organotin compounds and copper, commonly used as antifouling agent, were studied on Mercenaria mercernaria larvae. They were reared under usual hatchery conditions until they reached 190 um in diameter. The larvae were subjected to four compounds, tributylin chloride (TBT), monobutyltin chloride (MBT), trimethyltin chloride (TMT), cupric sulfate (CuSo4) plus control. Mortality was measured at 24, 48 h, and 96h. Behavioral and/or metamorphic changes were recorded in triplicate at 24-48 and 96 h. The appearance in swimming larvae of a functional foot was considered a sign of competence to set and was recorded as a "pediveliger". Swimming larvae were considered as larvae that have not yet reached their total development and they were recorded as "swimming". Larvae that did not show foot or swimming activity and were static but alive on the bottom were recorded as "bottom". TBT was found to completely inhibit swimming activity at sublethal concentrations throughout the period of observation. Copper and MBT inhibited swimming from 48 h, TMT did not inhibit swimming activity at any of the times recorded. The four compounds ranked in order of decreasing toxicity were TBT>TMT>CU>MBT.

Development and growth of hatchery-reared larval Florida pompano (Trachinotus carolinus)

Although the Florida pompano (Trachinotus carolinus) is a prime candidate for aquaculture, the problematic production of juveniles remains a major impediment to commercial culture of this species. In order to improve the understanding of larval development and to refine hatchery production techniques, this study was conducted to characterize development and growth of Florida pompano from hatching through metamorphosis by using digital photography and image analysis. Newly hatched larvae were transparent and had a large, elongate yolk sac and single oil globule. The lower and upper jaws as well as the digestive tract were not fully developed at hatching. Rotifers were observed in the stomach of larvae at three days after hatching (DAH), and Artemia spp. were observed in the stomach of larvae at 14 DAH. Growth rates calculated from total length measurements were 0.22 ±0.04, 0.23 ±0.12, and 0.35 ±0.09 mm/d for each of the larval rearing trials. The mouth gape of larvae was 0.266 ±0.075 mm at first feeding and increased with a growth rate of 0.13 ± 0.04 mm/d. Predicted values for optimal prey sizes ranged from 80 to 130 μm at 3 DAH, 160 to 267 μm at 5 DAH, and 454 to 757 μm at 10 DAH. Based on the findings of this study, a refined feeding regime was developed to provide stage- and size-specific guidelines for feeding Florida pompano larvae reared under hatchery con