Impact of fertlizers and pesticides on soil and water quality

[ES]En la presente tesis se ha estudiado el impacto de diferentes fertilizantes y pesticidas utilizados en la Zona Vulnerable de Vitoria-Gasteiz en la calidad del suelo y las aguas de dicha zona. Se ha podido constatar que hoy en día siguen lixiviándose cantidades significativas de nitratos y pesticidas (e.g., etofumesato y difenoconazol) a las aguas de la Zona Vulnerable, durante el cultivo de remolacha azucarera (Beta vulgaris L.), muy característico de la zona de estudio. Se comprobó que el alto contenido en nitratos de las aguas subterráneas en la Zona Vulnerable es mitigado, al menos en parte, por la acción de la actividad microbiana desnitrificante que alberga la zona riparia del humedal de Salburua. Dicho proceso, sin embargo, supone la emisión a la atmósfera de importantes cantidades de gases de efecto invernadero (CO2 y N2O), y puede verse afectado negativamente por la presencia de pesticidas (e.g., deltametrina) en el medio.Por otra parte, hemos observado que diversos pesticidas (deltametrina, etofumesato, difenoconazol) aplicados en concentraciones similares a las dosis de aplicación en campo inducen cambios, de carácter limitado y transitorio, en las comunidades microbianas edáficas, siendo más significativos en el caso del fungicida difenoconazol. El efecto de los pesticidas fue más acusado a medida que aumentaba su concentración en el medio. Finalmente, encontramos que la aplicación de abonos orgánicos (avicompost), en lugar de los fertilizantes sintéticos tradicionales (NPK), además de mejorar la degradación de los pesticidas y disminuir el impacto de éstos sobre la calidad del suelo, podría ayudar a reducir las pérdidas de nitratos por lixiviación.

Proximate composition and fatty acid and cholesterol content of 22 species of northwest Atlantic finfish

The moisture, fat, ash, fatty acid profile, and cholesterol content are reported for cooked and raw fillets from 22 species of finfish found in the Northwest Atlantic. All but nine species had 1%or less fat. Ocean perch and a spring sampling of mackerel and wolffiSh had about 2% fat, followed by yellowfin tuna, whiting, silver hake, butterfish, and a summer -sampling of mackerel and wolffish with a range of 3-7% fat. Herring had a range of 5-12% fat representing a winter sampling on the low end and summer sampling on the high end of the range. Bluefin tuna (a summer sampling) contained the most fat with a high of 23% fat. Omega-3 fatty acids were present in excess of omega-6 fatty acids. The fattier fISh supplied the most omega-3 fatty acids per gram of tissue. The mean cholesterol content for all species was 57 ± 16 mg/l00 g raw tissue. Finfish from the Northwest Atlantic would appear to fit into the regime for a healthy heart, being low in fat and cholesterol and rich in omega-3 fatty acids.(PDF file contains 42 pages.)

Stock assessment of the gulf menhaden, Brevoortia patronus, fishery

A stock assessment of the gulf menhaden. Brevoortia patronus, fishery was conducted with data on purse-seine landings from 1946 to 1985 and port sampling data from 1964 to 1985. These data were analyzed to determine growth rates, yield-per-recruit, spawner-recruit relationships, and maximum sustainable yield (MSY). Virtual population analysis was used to estimate stock size, year-class size, and fishing mortality rates. During the period studied, an average of 27% of age-l fish and 55% of age-2 and age-3 fish were taken by the fishery, and 54% for age-I and 38% for age-2 and -3 fish were lost annually to natural causes. Annual yield-per-recruit estimates ranged from 6.9 to 19.3 g, with recent mean conditions averaging 12.2 g since 1978. Surplus production models produced estimates of MSY from 620 to 700 kilometric tons. Recruits to age-I ranged from 8.3 to 41.8 billion fish for 1964-82. Although there was substantial scatter about the fitted curves, Ricker·type spawner-recruit relationships were found suitable for use in a population simulation model. Estimates of MSY from population simulation model runs ranged from 705 to 825 kilometric tons with F -multiples of the mean rate of fishing ranging from 1.0 to 1.5. Recent harvests in excess of the historical MSY may not be detrimental to the gulf menhaden stock. However, one should not expect long-term harvesting above the historical MSY because of the short life span of gulf menhaden and possible changes from currently favorable environmental conditions supporting high recruitment.(PDF file contains 24 pages.)

New Oncogenic Drivers in Hepatocellular Carcinoma: Role of the RNA Binding Protein Hu antigen R

156 p. : graf.

Proceedings of the International Workshop on age determination of oceanic pelagic fishes: Tunas, billfishes, and sharks, Miami, Florida, February 15-18,1982

Accurate and precise estimates of age and growth rates are essential parameters in understanding the population dynamics of fishes. Some of the more sophisticated stock assessment models, such as virtual population analysis, require age and growth information to partition catch data by age. Stock assessment efforts by regulatory agencies are usually directed at specific fisheries which are being heavily exploited and are suspected of being overfished. Interest in stock assessment of some of the oceanic pelagic fishes (tunas, billfishes, and sharks) has developed only over the last decade, during which exploitation has increased steadily in response to increases in worldwide demand for these resources. Traditionally, estimating the age of fishes has been done by enumerating growth bands on skeletal hardparts, through length frequency analysis, tag and recapture studies, and raising fish in enclosures. However, problems related to determining the age of some of the oceanic pelagic fishes are unique compared with other species. For example, sampling is difficult for these large, highly mobile fishes because of their size, extensive distributions throughout the world's oceans, and for some, such as the marlins, infrequent catches. In addition, movements of oceanic pelagic fishes often transect temperate as well as tropical oceans, making interpretation of growth bands on skeletal hardparts more difficult than with more sedentary temperate species. Many oceanic pelagics are also long-lived, attaining ages in excess of 30 yr, and more often than not, their life cycles do not lend themselves easily to artificial propagation and culture. These factors contribute to the difficulty of determining ages and are generally characteristic of this group-the tunas, billfishes, and sharks. Accordingly, the rapidly growing international concern in managing oceanic pelagic fishes, as well as unique difficulties in ageing these species, prompted us to hold this workshop. Our two major objectives for this workshop are to: I) Encourage the interchange of ideas on this subject, and 2) establish the "state of the art." A total of 65 scientists from 10 states in the continental United States and Hawaii, three provinces in Canada, France, Republic of Senegal, Spain, Mexico, Ivory Coast, and New South Wales (Australia) attended the workshop held at the Southeast Fisheries Center, Miami, Fla., 15-18 February 1982. Our first objective, encouraging the interchange of ideas, is well illustrated in the summaries of the Round Table Discussions and in the Glossary, which defines terms used in this volume. The majority of the workshop participants agreed that the lack of validation of age estimates and the means to accomplish the same are serious problems preventing advancements in assessing the age and growth of fishes, particularly oceanic pelagics. The alternatives relating to the validation problem were exhaustively reviewed during the Round Table Discussions and are a major highlight of this workshop. How well we accomplished our second objective, to establish the "state of the art" on age determination of oceanic pelagic fishes, will probably best be judged on the basis of these proceedings and whether future research efforts are directed at the problem areas we have identified. In order to produce high-quality papers, workshop participants served as referees for the manuscripts published in this volume. Several papers given orally at the workshop, and included in these proceedings, were summarized from full-length manuscripts, which have been submitted to or published in other scientific outlets-these papers are designated as SUMMARY PAPERS. In addition, the SUMMARY PAPER designation was also assigned to workshop papers that represented very preliminary or initial stages of research, cursory progress reports, papers that were data shy, or provide only brief reviews on general topics. Bilingual abstracts were included for all papers that required translation. We gratefully acknowledge the support of everyone involved in this workshop. Funding was provided by the Southeast Fisheries Center, and Jack C. Javech did the scientific illustrations appearing on the cover, between major sections, and in the Glossary. (PDF file contains 228 pages.)

Kabeljaukrise in der Nordsee erfordert neue bestandserhaltende Maßnahmen

The European Commission has claimed a fundamental revision of the European Common Fisheries Policy in its Green Paper (EC 2001) by highlighting the reasons of continued overfishing of a number of valuable demersal fish stocks. Quotas in excess of scientific recommendations, fleet over capacities and poor enforcement of management decisions were identified causal for major stock and yield reductions while gaps in scientific advices were also criticized. The depleted cod stock in the North Sea, Skagerrak and Eastern Channel is the most prominent example. Existing and proposed management regulations were analysed by an expert group which met with fishing industry consultations in Brussels during 28 April – 7 May 2003. Depending on compliance with new technical regulations since 2000, the cod stock and its exploitation was found only marginally effected, while whiting displayed immediately significant losses in yield over long term and short term losses in haddock yields were reversed in substantial gains, also in SSB. However, reduction in fishing effort was found more effective in recovery potential than technical changes including closed areas, for which detailed information about variation in distribution of the stocks and the fisheries are required. Such effort reductions would reduce not only landings but also unregulated discarding, which is believed to be a major reason of the failure of the management measures in mixed fisheries. Recent trends in fishing effort of European fleets could not be quantified due to persistent data deficiencies.

Einfluss der Umsetzung der ICES-Fangempfehlungen auf den Zustand der Fischbest

The implementation of the precautionary approach in the mid-1990s required commercial fish stocks to be classified into different categories. These are based on the degree to which stocks have been exploited or are threatened by fishing activities. According to current ICES terminology, stocks are classified as being either “within” or “outside safe biological limits”, or as being “harvested outside safe biological limits”. Between 1996 and 2002, the relative share of stocks in these three categories remained relatively stable (at about 20 %, 30 % and 15 %, respectively). Over the same time span, the number of stocks were insufficient data is available to quantify and thus to appropriately classify the state of the spawning stock biomass (“status unknown”) has increased. Neglecting potential impacts of fishing pressure, the combined average proportion of all stocks with sufficiently high spawning stock biomass is at about one third, while only one fifth of the stocks assessed have been managed sustainably. For some important fish stocks in the ICES environment – specifically demersal ones –, science recently had to call for rebuilding plans or even a closure of the fishery to allow recovery, in spite of the management’s agreement to manage the resources according to the precautionary approach. This obvious difference between approach and implementation has a number of potential causes: erroneous or imprecise input data (landings, discard and sampling information), insufficient assessment models, problems in the understanding of the scientific advice, and implementation errors. The latter could be either a difference between advised and implemented total allowable catches (TACs), or an excess of legal TACs. During the fifteen years covered by this analysis (1987 to 2002), the average deviation between the implemented TACs for a specific stock and that recommended by ICES for the same stock was more than 30 %. The overall average deviation (summed over all stocks) for the entire period was 34 %, excluding, however, four extreme outliers in the data, representing cases in which scientific recommendations were exceeded by as much as 1000 to 2500 %. If these were included, the overall average would be as high as 45 %. The annual deviation has substantially increased in recent years (from roughly 20 % in earlier years of the surveyed period). This recently observed high deviation also matches ICES’s estimate that the fishing mortality in the ICES convention area in the 1990s was well above recommended sustainable levels in the pelagic and demersal fishery. A direct comparison of scientifically proposed and politically implemented TACs is problematic in many case

Studies of the equation of state and elasticity of mantle minerals

Because the Earth’s upper mantle is inaccessible to us, in order to understand the chemical and physical processes that occur in the Earth’s interior we must rely on both experimental work and computational modeling. This thesis addresses both of these geochemical methods. In the first chapter, I develop an internally consistent comprehensive molar volume model for spinels in the oxide system FeO-MgO-Fe₂O₃-Cr₂O₃-Al₂O₃-TiO₂. The model is compared to the current MELTS spinel model with a demonstration of the impact of the model difference on the estimated spinel-garnet lherzolite transition pressure. In the second chapter, I calibrate a molar volume model for cubic garnets in the system SiO₂-Al₂O₃-TiO₂-Fe₂O₃-Cr₂O₃-FeO-MnO-MgO-CaO-Na₂O. I use the method of singular value analysis to calibrate excess volume of mixing parameters for the garnet model. The implications the model has for the density of the lithospheric mantle are explored. In the third chapter, I discuss the nuclear inelastic X-ray scattering (NRIXS) method, and present analysis of three orthopyroxene samples with different Fe contents. Longitudinal and shear wave velocities, elastic parameters, and other thermodynamic information are extracted from the raw NRIXS data.

Deepwater shorelines

Research has proven that Shoreline Erosion is caused by excess water contained within the shore face. This Research presents an opportunity to control erosion by managing the near shore water table. Our Research on Bogue Banks North Carolina suggests that our buildings and other impervious surfaces collect and concentrate water from storm rain runoff into the surface water table and within the critical beach front water exit point. Presently our Potable Fresh Water is supplied from deep wells located beneath an impervious layer of Marl. After our use, the Waste water is drained into the Surface Aquifer, the combined waste and storm rain water raises the Surface Aquifer water table and produces Erosion. The Deep Aquifers presently supplying our Potable Water have an unknown recharge rate, with increasing reports of Salt Water intrusion. We believe our Vital Fresh water supply system should be modified to supply Reverse Osmosis treatment plants from shallow wells. This will lower the Surface Water Table. These Shallow wells, either horizontal or vertical, might be located within the beach front, adjacent to high erosion risk properties. Beach Drains and Reverse Osmosis Water systems are new and proven technologies. By combining these technologies we can reduce or reverse Shore Erosion, ensure a safe Potable Water supply, reduce requirements for periodic beach nourishment, reduce taxes and protect our property well into the Future. (PDF contains 5 pages)

Searches for new symmetries in pp collisions with the razor kinematic variables at √s = 7 TeV

The construction and LHC phenomenology of the razor variables M_R, an event-by-event indicator of the heavy particle mass scale, and R, a dimensionless variable related to the transverse momentum imbalance of events and missing transverse energy, are presented.  The variables are used  in the analysis of the first proton-proton collisions dataset at CMS  (35 pb^-1) in a search for superpartners of the quarks and gluons, targeting indirect hints of dark matter candidates in the context of supersymmetric theoretical frameworks. The analysis produced the highest sensitivity results for SUSY to date and extended the LHC reach far beyond the previous Tevatron results.  A generalized inclusive search is subsequently presented for new heavy particle pairs produced in √s = 7 TeV proton-proton collisions at the LHC using 4.7±0.1 fb^-1 of integrated luminosity from the second LHC run of 2011.  The selected events are analyzed in the 2D razor-space of M_R and R and the analysis is performed in 12 tiers of all-hadronic, single and double leptons final states in the presence and absence of b-quarks, probing the third generation sector using the event heavy-flavor content.   The search is sensitive to generic supersymmetry models with minimal assumptions about the superpartner decay chains. No excess is observed in the number or shape of event yields relative to Standard Model predictions. Exclusion limits are derived in the CMSSM framework with  gluino masses up to 800 GeV and squark masses up to 1.35 TeV excluded at 95% confidence level, depending on the model parameters. The results are also interpreted for a collection of simplified models, in which gluinos are excluded with masses as large as 1.1 TeV, for small neutralino masses, and the first-two generation squarks, stops and sbottoms are excluded for masses up to about 800, 425 and 400 GeV, respectively.

With the discovery of a new boson by the CMS and ATLAS experiments in the γ-γ and 4 lepton final states, the identity of the putative Higgs candidate must be established through the measurements of its properties. The spin and quantum numbers are of particular importance, and we describe a method for measuring the J^PC of this particle using the observed signal events in the H to ZZ^* to 4 lepton channel developed before the discovery. Adaptations of the razor kinematic variables are introduced for the H to WW^* to 2 lepton/2 neutrino channel, improving the resonance mass resolution and increasing the discovery significance. The prospects for incorporating this channel in an examination of the new boson J^PC is discussed, with indications that this it could provide complementary information to the H to ZZ^* to 4 lepton final state, particularly for measuring CP-violation in these decays.

Essays in mechanism design

This dissertation contains three essays on mechanism design. The common goal of these essays is to assist in the solution of different resource allocation problems where asymmetric information creates obstacles to the efficient allocation of resources. In each essay, we present a mechanism that satisfactorily solves the resource allocation problem and study some of its properties. In our first essay, ”Combinatorial Assignment under Dichotomous Preferences”, we present a class of problems akin to time scheduling without a pre-existing time grid, and propose a mechanism that is efficient, strategy-proof and envy-free. Our second essay, ”Monitoring Costs and the Management of Common-Pool Resources”, studies what can happen to an existing mechanism — the individual tradable quotas (ITQ) mechanism, also known as the cap-and-trade mechanism — when quota enforcement is imperfect and costly. Our third essay, ”Vessel Buyback”, coauthored with John O. Ledyard, presents an auction design that can be used to buy back excess capital in overcapitalized industries.

Cu2O substrates and epitaxial Cu2O/ZnO thin film hetero-structures for solar energy conversion

Future fossil fuel scarcity and environmental degradation have demonstrated the need for renewable, low-carbon sources of energy to power an increasingly industrialized world. Solar energy with its infinite supply makes it an extraordinary resource that should not go unused. However with current materials, adoption is limited by cost and so a paradigm shift must occur to get everyone on the same page embracing solar technology. Cuprous Oxide (Cu2O) is a promising earth abundant material that can be a great alternative to traditional thin-film photovoltaic materials like CIGS, CdTe, etc. We have prepared Cu2O bulk substrates by the thermal oxidation of copper foils as well Cu2O thin films deposited via plasma-assisted Molecular Beam Epitaxy. From preliminary Hall measurements it was determined that Cu2O would need to be doped extrinsically. This was further confirmed by simulations of ZnO/Cu2O heterojunctions. A cyclic interdependence between, defect concentration, minority carrier lifetime, film thickness, and carrier concentration manifests itself a primary reason for why efficiencies greater than 4% has yet to be realized. Our growth methodology for our thin-film heterostructures allow precise control of the number of defects that incorporate into our film during both equilibrium and nonequilibrium growth. We also report process flow/device design/fabrication techniques in order to create a device. A typical device without any optimizations exhibited open-circuit voltages Voc, values in excess 500mV; nearly 18% greater than previous solid state devices.

Selective hydroxylation of small alkanes by the particulate methane monooxygenase

The particulate methane monooxygenase (pMMO) catalyzes the oxidation of methane to methanol under ambient temperatures and pressures. Other small alkanes and alkenes are also substrates of this enzyme. We measured and compared the initial rate constants of oxidation of small alkanes (C1 to C5) catalyzed by pMMO. Both primary and secondary alcohols were formed from oxidation of n-butane and n-pentane. The alcohols produced from alkane oxidation can be further oxidized, probably by pMMO, to aldehydes and ketones. The apparent regioselectivity for n-butane and n-pentane is 100% 2-alcohols because the formation of primary alcohols is slower than further oxidation of these alcohols. The hydroxylation at the secondary carbons is highly stereoselective: (R)-alcohols are preferentially formed. The enantiomeric excess increases slightly with decreasing reaction temperature. The steric course of hydroxylation on primary carbons was also studied by using isotopically substituted ethane: (S)- or (R)-CH_3-CHDT, and (S)- or (R)-CD_3- CHDT and the reactions were found to proceed with 100% retention of configuration. A primary isotopic effect of k_H/k_D=5.0 was observed in these experiments.

Synthetic and structural studies of permethylscandocene and permethyltantalocene derivatives

Cp*_2Sc-H reacts with H_2 and CO at -78°C to yield Cp*_2ScOCH_3. A stepwise reduction of CO to an alkoxide is observed when CO reacts with Cp*_2ScC_6H_4CH_3-p to give the η^2-acyl Cp*_2Sc(CO)C_6H_4CH_3-p, which then reacts with H_2 to produce Cp*_2ScOCH_2C_6H_4CH_3-p. Cp*_2ScCH_3 and Cp*_2ScH(THF) react with CO to give unchar- uncharacterizable products. Cp*_2ScH and Cp*_2ScCH_3 react with Cp_2MCO (M = Mo, W) to give scandoxycarbenes, Cp_2M=C(CH_3)OScCp*_2, while a wide variety of Cp*_2ScX (X = H, CH_3, N(CH_3)_2, CH_2CH_2C_6H_5) reacts with CpM(CO)_2 (M = Co, Rh) to yield similar carbene complexes. An x-ray crystal structure determination of Cp(CO)Co=C(CH_3)- OScCp*_2 revealed a µ^2: η^1, η^1 carbonyl interaction between the Co-CO and Sc.

CO_2 inserts cleanly into Sc-phenyl bonds at -78°C to produce a carboxylate complex, Cp*_2Sc(O_2C)C_6H_4CH_3-p. The structure of this compound was determined by x-ray crystallographic techniques.

Excess C_2H_2 reacts with Cp*_2ScR (R = H, alkyl, aryl, alkenyl, alkynyl, amide) at temperatures below -78°C to form the alkynyl species Cp*_2Sc-C≡C-H, which then reacts with the remaining acetylene to form polyacetylene. Cp*_2Sc-C≡C-H further reacts to yield Cp*_2sc-C≡C-ScCp*_2. This unusual C_2 bridged dimer was characterized by x-ray crystallography.

Attempts were made to model the C-N bond breaking step of hydrodenitrogenation by synthesizing Cp*_2TaH(η^2-H_2C=N(C_6H_4X)) and studying its rearrangement to Cp*_2Ta(=N(C_6H_4X))(CH_3). The 1,2 addition/elimination reactions of Cp*_2Ta(η^2- H_2C=N(CH_3)H and Cp*_2Ta(=X)H (X=O, S, NH, N(C_6H_5)) were investigated. Cp*_2Ta(=NH)H was found to react with D_2 to give Cp*_2Ta(=ND)H, implying a nonsymmetric amide-dihydride intermediate for the addition/elimination process. Cp*_2Ta(=S)H and H_2O equilibrate with Cp*_2Ta(=O)H and H_2S, which allowed determination of the difference in bond strengths for Ta=O and Ta=S. Ta=O was found to be approximately 41 kcals/mole stronger than Ta=S.

Catalytic conversion of nitrogen to ammonia by an iron model complex

Threefold symmetric Fe phosphine complexes have been used to model the structural and functional aspects of biological N₂ fixation by nitrogenases. Low-valent bridging Fe-S-Fe complexes in the formal oxidation states Fe(II)Fe(II), Fe(II)/Fe(I), and Fe(I)/Fe(I) have been synthesized which display rich spectroscopic and magnetic behavior. A series of cationic tris-phosphine borane (TPB) ligated Fe complexes have been synthesized and been shown to bind a variety of nitrogenous ligands including N₂H₄, NH₃, and NH₂-. These complexes are all high spin S = 3/2 and display EPR and magnetic characteristics typical of this spin state. Furthermore, a sequential protonation and reduction sequence of a terminal amide results in loss of NH₃ and uptake of N₂. These stoichiometric transformations represent the final steps in potential N₂ fixation schemes.

Treatment of an anionic FeN₂ complex with excess acid also results in the formation of some NH₃, suggesting the possibility of a catalytic cycle for the conversion of N₂ to NH₃ mediated by Fe. Indeed, use of excess acid and reductant results in the formation of seven equivalents of NH₃ per Fe center, demonstrating Fe mediated catalytic N₂ fixation with acids and protons for the first time. Numerous control experiments indicate that this catalysis is likely being mediated by a molecular species.

A number of other phosphine ligated Fe complexes have also been tested for catalysis and suggest that a hemi-labile Fe-B interaction may be critical for catalysis. Additionally, various conditions for the catalysis have been investigated. These studies further support the assignment of a molecular species and delineate some of the conditions required for catalysis.

Finally, combined spectroscopic studies have been performed on a putative intermediate for catalysis. These studies converge on an assignment of this new species as a hydrazido(2-) complex. Such species have been known on group 6 metals for some time, but this represents the first characterization of this ligand on Fe. Further spectroscopic studies suggest that this species is present in catalytic mixtures, which suggests that the first steps of a distal mechanism for N₂ fixation are feasible in this system.