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1.
Water Sci Technol ; 67(1): 33-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23128618

RESUMEN

The European Water Framework Directive (WFD) was enacted in the year 2000 with a stepwise approach. After legal implementation in the various member states large efforts were undertaken for the initial characterization of water bodies, risk assessment, to implement extensive monitoring schemes and to develop management plans at different aggregation levels by the year 2010. The initial characterization process and risk assessment had to be finalized by 2004 and delineated water bodies including a typological classification and identified the significant pressures and impacts in a screening procedure. In parallel, monitoring programmes and new biological indicator systems were developed in order to proof and refine the results of the risk assessment with an ecological indicator based assessment in a subsequent step which was finalized in 2009. Although the risk assessment for Germany was based on existing data that were originally collected for other purposes and came from a large variety of environmental or economical sectors, the results differ only slightly from the monitoring and indicator based information with respect to classifications of the 'ecological status' and 'chemical status'. From this result we conclude that a risk assessment based on a careful application and intelligent combination of existing data sources with proven quality allows the recognition of trends and the identification of priorities for action of measures already at an early stage of a management process. However, monitoring schemes and advanced sets of ecological indicators are essential in later management steps both for narrowing uncertainties remaining from the risk assessment and to allow for effect controls of implemented measures. Moreover, these monitoring indicators should differentiate the effects of multiple stressors more factor specific and with respect to ecosystem states and functions. In conclusion, we see risk and indicator based assessments as complementary elements in Integrated Water Resources Management (IWRM), which have to be linked in systematic and phased procedures.


Asunto(s)
Monitoreo del Ambiente/métodos , Agua/química , Alemania , Cinética , Modelos Teóricos , Factores de Riesgo , Contaminantes Químicos del Agua/química , Contaminación Química del Agua
2.
Water Sci Technol ; 63(12): 3013-9, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22049732

RESUMEN

Particulate matter in stormwater deteriorates the quality of receiving water and sediment. Characterization of stormwater particulate matter by means of its particle-associated element pattern provides an aid to determining its impact on receiving surface waters. During a 6 month measurement campaign, we determined particle-associated concentrations of major pollutants and rare earths for three combined water/stormwater outlets in the town of Stassfurt. We differentiated the particle-associated constituents on the basis of a hierarchical cluster analysis. Repeating the cluster analysis on random subsets, we gained information about the variability of the element patterns between and within the sites. In general, constituents associated with sewage and sewer sediment behave differently compared with constituents associated with runoff. The degree to which associations can be established for element patterns from site to site is limited by the variability encountered within sample sets taken from individual sites. The latter variability depends on the complexity of the catchment.


Asunto(s)
Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Metales de Tierras Raras/análisis , Material Particulado/química , Aguas del Alcantarillado/química , Contaminantes Químicos del Agua/análisis , Análisis por Conglomerados , Monitoreo del Ambiente/estadística & datos numéricos , Alemania , Tamaño de la Partícula
3.
Nat Commun ; 8: 15708, 2017 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-28585529

RESUMEN

Rapid identification of agronomically important genes is of pivotal interest for crop breeding. One source of such genes are crop wild relative (CWR) populations. Here we used a CWR population of <200 wild beets (B. vulgaris ssp. maritima), sampled in their natural habitat, to identify the sugar beet (Beta vulgaris ssp. vulgaris) resistance gene Rz2 with a modified version of mapping-by-sequencing (MBS). For that, we generated a draft genome sequence of the wild beet. Our results show the importance of preserving CWR in situ and demonstrate the great potential of CWR for rapid discovery of causal genes relevant for crop improvement. The candidate gene for Rz2 was identified by MBS and subsequently corroborated via RNA interference (RNAi). Rz2 encodes a CC-NB-LRR protein. Access to the DNA sequence of Rz2 opens the path to improvement of resistance towards rhizomania not only by marker-assisted breeding but also by genome editing.


Asunto(s)
Beta vulgaris/genética , Mapeo Contig , Edición Génica , Genes de Plantas , Alelos , Productos Agrícolas/genética , Resistencia a la Enfermedad/genética , Ecosistema , Estudios de Asociación Genética , Variación Genética , Genoma de Planta , Geografía , Hibridación Genética , Sistemas de Lectura Abierta , Fenotipo , Fitomejoramiento , Enfermedades de las Plantas/genética , Polimorfismo de Nucleótido Simple , Interferencia de ARN
4.
Biochim Biophys Acta ; 1571(2): 138-50, 2002 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-12049794

RESUMEN

Induction of gluconeogenesis is accelerated in larvae of the insect Manduca sexta L. parasitized by Cotesia congregata (Say), maintaining the concentration of the blood sugar trehalose, an important nutrient for parasite development. Investigation has demonstrated that when host larvae are offered a choice of diets with varying levels of sucrose and casein, parasitized insects consume a different balance of these nutrients, principally due to a decrease in protein consumption. The result is metabolic homeostasis, with normal unparasitized and parasitized larvae exhibiting similar levels of gluconeogenesis and blood sugar level. In the present study, normal unparasitized and parasitized larvae were maintained on individual chemically defined diets having the balance of protein and carbohydrate consumed by each when offered a dietary choice. Total dietary nutrient, the sum of carbohydrate and protein, was provided at six levels, composed of three pairs of diets. Each diet pair consisting of diets having equivalent overall nutrient ratios of 2:1 and 1:1 casein/sucrose. Host growth and diet consumption were significantly affected by dietary nutrient level and the magnitude of these effects was influenced by parasitism. Due to the effects of dietary nutrient level on diet consumption, none of the unparasitized and parasitized larvae within any of the three diet pairs consumed protein and carbohydrate at the levels predicted by the earlier choice experiments. Among insects on all of the diets, however, two groups of unparasitized and parasitized larvae consumed the expected levels of protein and carbohydrate. In each case, gluconeogenesis, as measured by 13C nuclear magnetic resonance spectroscopy (NMR) analysis of pyruvate cycling and trehalose synthesis from [2-13C]pyruvate, was evident in unparasitized and parasitized insects, confirming the conclusions of the earlier experiments. Generally, all larvae that consumed less than approximately 250 mg of sucrose over the 3-day feeding period, were gluconeogenic, regardless of diet. Differential carbohydrate consumption, therefore, was an important factor in inducing gluconeogenesis in both unparasitized and parasitized insects. The selective 13C enrichment in trehalose displayed by non-gluconeogenic larvae on some diets demonstrated trehalose formation from [2]pyruvate. The absence of net carbohydrate synthesis in these insects was likely due to an elevation of glycolysis. There was no significant effect of diet consumption or parasitism on blood trehalose level. Parasitized larvae displayed higher levels of gluconeogenesis than did unparasitized insects, a finding consistent with the conclusion that blood sugar is rapidly sequestered by developing parasites. The parasite burden, the total number of parasites developing within host larvae, as well as the number of parasites emerging from host larvae to complete development, was significantly less at the lowest dietary nutrient level, but was otherwise similar at all dietary nutrient levels. Moreover, the number of parasites that emerged increased with increasing diet consumption as reflected by host final weight.


Asunto(s)
Himenópteros/fisiología , Manduca/metabolismo , Manduca/parasitología , Trehalosa/sangre , Animales , Caseínas/metabolismo , Gluconeogénesis , Interacciones Huésped-Parásitos/efectos de los fármacos , Interacciones Huésped-Parásitos/fisiología , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Larva/metabolismo , Larva/parasitología , Manduca/efectos de los fármacos , Manduca/crecimiento & desarrollo , Sacarosa/metabolismo
5.
Biol Psychiatry ; 32(11): 976-91, 1992 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-1467389

RESUMEN

The psychological, neuropsychological, and neurometabolic effects of the hallucinogenic agent mescaline were investigated in 12 normal men who were volunteers. Mescaline produced an acute psychotic state 3 1/2-4 hr after drug intake, as measured by the Brief Psychiatric Rating Scale (BPRS) and Paranoid Depression Scale (PDS). The Assessment of Altered States of Consciousness (APZ) questionnaire revealed specific effects of mescaline in the visual system. Neuropsychological effects were studied with a face/nonface decision task with known right-hemisphere advantage, in which mescaline induced a decrease of functioning of the right hemisphere. In functional brain imaging using single photon emission computed tomography (SPECT), mescaline produced a "hyperfrontal" pattern with an emphasis on the right hemisphere, which was correlated with mescaline-induced psychotic psychopathology. Our findings question the validity of the concept of hypofrontality as an explanation for schizophrenic symptomatology. The study of psychoactive substances under controlled laboratory conditions has the methodological advantage of intraindividual control, and hence, minimal variability of data.


Asunto(s)
Corteza Cerebral/efectos de los fármacos , Metabolismo Energético/efectos de los fármacos , Mescalina/toxicidad , Trastornos Neurocognitivos/fisiopatología , Pruebas Neuropsicológicas , Escalas de Valoración Psiquiátrica , Adulto , Atención/efectos de los fármacos , Atención/fisiología , Mapeo Encefálico/instrumentación , Corteza Cerebral/fisiopatología , Aprendizaje Discriminativo/efectos de los fármacos , Aprendizaje Discriminativo/fisiología , Dominancia Cerebral/efectos de los fármacos , Dominancia Cerebral/fisiología , Metabolismo Energético/fisiología , Lóbulo Frontal/irrigación sanguínea , Humanos , Procesamiento de Imagen Asistido por Computador/instrumentación , Masculino , Persona de Mediana Edad , Trastornos Neurocognitivos/psicología , Reconocimiento Visual de Modelos/efectos de los fármacos , Reconocimiento Visual de Modelos/fisiología , Esquizofrenia/inducido químicamente , Esquizofrenia/fisiopatología , Psicología del Esquizofrénico , Tomografía Computarizada de Emisión de Fotón Único/instrumentación
6.
Neuropsychopharmacology ; 8(2): 171-6, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8471129

RESUMEN

The so-called entactogens 3,4-methylenedioxymethamphetamine ([MDMA] also known as "Ecstasy," or "Adam") and its analog 3,4-methylenedioxyethamphetamine ([MDE] also known as "Eve") exert similar psychotropic effects in humans. Two double-blind placebo-controlled psychometric studies with normal control subjects were conducted. Placebo or MDE (140 mg) was administered orally to eight male volunteers at 1:30 P.M. and to six subjects (3 male, 3 female) at 11 P.M. Psychologic tests and clinical ratings were performed 1 hour before the administration of the drugs, as well as 2, 5, and 24 hours after drug intake and 7 days thereafter in the first study. In the second study, measures were taken at times -1, +8.5, +24 hours, and +7 days. The majority of the psychotropic effects resembled those that have already been described in anecdotal reports. The substance produced a partially controllable state of enhanced insight, empathy, and peaceful feelings. All subjects displayed a general stimulation with increased psychomotor drive, logorrhea, and facilitation of communication. One of the fourteen volunteers developed a toxic psychosis. One volunteer displayed a dysphoric reaction, one suffered from episodes of anxiety for some days after the experiment. The findings support the hypothesis that MDMA and MDE represent a novel pharmacologic class.


Asunto(s)
3,4-Metilenodioxianfetamina/análogos & derivados , Trastornos Mentales/inducido químicamente , 3,4-Metilenodioxianfetamina/farmacología , Adulto , Método Doble Ciego , Femenino , Humanos , Masculino , Trastornos Mentales/psicología , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Pruebas Psicológicas , Valores de Referencia
7.
Biochem Pharmacol ; 45(1): 183-9, 1993 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-8424811

RESUMEN

The effects of 1-stearoyl,2-sn-arachidonoylglycerol (SAG) and the antimalarial drug chloroquine on lipid bilayer structure were studied by 2H-NMR spectroscopy. Model lipid systems were established with compositions similar to those of normal human erythrocytes, malaria-infected erythrocytes, or malaria parasite membranes. The 2H-NMR spectra of the membranes formed from the lipids extracted from normal human erythrocytes were similar to those obtained using the corresponding lipid mixtures. The order parameters of the model "infected" and model "parasite" membranes were reduced markedly relative to that of normal erythrocytes. Addition of SAG induced formation of non-bilayer lipid phases in all lipid systems. Only a small decrease in the order parameters of the acyl side chains of the phosphatidylserine, but not of the phosphatidylcholine component of the lipid membranes, was observed upon the addition of chloroquine. A dramatic effect was observed upon the addition of chloroquine to the SAG-containing membranes: this antimalarial almost totally abolished the formation of SAG-induced non-bilayer lipid phases. Since SAG, endogenously formed in erythrocyte membranes, is a potent activator of phospholipase A2, this membrane-stabilizing action of chloroquine may partially account for the phospholipase A2-inhibiting properties of this drug, and, consequently, for both its therapeutic and toxic modes of action.


Asunto(s)
Cloroquina/farmacología , Diglicéridos/farmacología , Membrana Eritrocítica/química , Membrana Dobles de Lípidos/química , Fosfolípidos/sangre , Cloroquina/química , Interacciones Farmacológicas , Membrana Eritrocítica/efectos de los fármacos , Humanos , Espectroscopía de Resonancia Magnética , Fosfolipasas A/antagonistas & inhibidores , Fosfolipasas A2
8.
Phytopathology ; 88(4): 322-9, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18944955

RESUMEN

ABSTRACT Northern leaf blight, caused by Setosphaeria turcica, is a serious disease of maize in temperate and tropical environments. To examine the pathogen's population structure, we analyzed 264 isolates from four different continents with 70 random amplified polymorphic DNA markers and determined their mating types. Tropical populations (from Kenya, Mexico, and southern China) had an extremely high genotypic diversity, no or only weak gametic phase disequilibrium, and an even distribution of the two mating types, indicating frequent sexual recombination. Temperate populations (from Europe and northern China) had a much lower genotypic diversity, strong gametic phase disequilibrium, and an uneven distribution of mating types, indicating that sexual recombination has been rare. Populations in different continents were genetically isolated. They shared no haplotypes and carried several "private" alleles. The number of migrants between continents and between regions (between northern and southern China, western and central Kenya, and Europe west and east of the Alps) was estimated to be less than one per generation. Multivariate statistics suggested a greater relatedness of populations from the same continents than from different continents. Within agroecological zones, migration must be extensive. The potential within populations of S. turcica for adaptation should be regarded as very high, especially in tropical climates.

9.
Comp Biochem Physiol B Biochem Mol Biol ; 135(3): 461-71, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12831766

RESUMEN

Gluconeogenesis and blood sugar formation were examined in Manduca sexta, fed carbohydrate- and fat-free diets with varying levels of casein. De novo carbohydrate synthesis was examined by nuclear magnetic resonance spectroscopy of the 13C enrichment in blood trehalose and alanine derived from (2-(13)C)pyruvate and (2,3-(13)C(2))pyruvate administered to 5th instar larvae. Gluconeogenic flux and blood trehalose concentration were positively correlated with protein consumption. On all diets, the 13C distribution in trehalose was asymmetric, with C6 more highly enriched than C1. The C6/C1 13C enrichment ratio, however, decreased with increased protein consumption and gluconeogenic flux. Although the asymmetric 13C enrichment pattern in trehalose is consistent with pentose cycling via the pentose phosphate pathway following de novo synthesis, experiments employing [2,3-(13)C(2)]pyruvate demonstrated that pentose cycling is not detected in insects under these nutritional conditions. Analysis of the multiplet NMR signal structure in trehalose due to spin-spin coupling between adjacent 13C enriched carbons showed the absence of uncoupling expected by pentose phosphate pathway activity. Here we suggest that the asymmetric 13C distribution in trehalose results from a disequilibrium of the triose phosphate isomerase-catalyzed reaction.


Asunto(s)
Glucemia/biosíntesis , Gluconeogénesis , Manduca/metabolismo , Ácido Pirúvico/metabolismo , Trehalosa/biosíntesis , Animales , Glucemia/análisis , Isótopos de Carbono , Caseínas/farmacología , Proteínas en la Dieta/farmacología , Ingestión de Alimentos/efectos de los fármacos , Manduca/efectos de los fármacos , Manduca/crecimiento & desarrollo , Manduca/fisiología , Trehalosa/sangre
10.
Rofo ; 143(6): 710-3, 1985 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-3001867

RESUMEN

Homogeneous distribution of electrons used for therapeutic purposes and obtained from accelerators, is achieved by means of Potter-Bucky diaphragms or by repeated, staggered, sawtooth-shaped sweeping movements of the electron beam (scanning) over the radiation field. The repetition of the scanning process (number of scans) can result in long measurement times for achieving a sufficiently homogeneous, dosimetrically adequate distribution of the electrons. This "time problem" makes it imperative to achieve good homogeneity while keeping the number of scans as low as possible. To solve the problem, the scanning movement of the electron beam is simulated by a computer programme and the interdependence of the homogeneity of the irradiation field and number of scans is investigated. Since changing the ratio of the two deflection rates exercises a significant influence, it is mandatory in dosimetry to pay close attention to a strict observance of the deflection rates.


Asunto(s)
Aceleradores de Partículas , Dosis de Radiación , Humanos , Modelos Teóricos
11.
J Parasitol ; 85(4): 603-7, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10461938

RESUMEN

Moderate activity of arginine kinase was found in Steinernema carpocapsae, an entomopathogenic nematode. In the forward reaction, 4.60 and 3.12 micromol ATP/min/mg protein was produced in infectious third-stage juveniles (J3s) and adult nematodes, respectively. For the reverse reaction, 3.20 and 2.27 micromol phosphoarginine/min/mg protein was produced by J3s and adults, respectively. The K(m)s for phosphoarginine and ADP were 0.73 and 0.42 mM, respectively, in the forward reaction, whereas in the reverse reaction, the K(m)s were 0.37 and 2.35 mM for arginine and ATP, respectively, for the enzyme from J3s. The pH optimum for the forward reaction was 7.2 and 7.3 in J3s and adults, respectively. The pH optimum was elevated for the reverse reaction, 7.8 and 7.9-8.5 in J3s and adults, respectively. In the J3s, the in vitro optima for arginine kinase activity was correlated with the in vivo tissue pH in hypoxic (6.9) and aerobic (7.5) J3s estimated by in vivo flow 31P-NMR.


Asunto(s)
Arginina Quinasa/metabolismo , Arginina/análogos & derivados , Rhabditoidea/fisiología , Aerobiosis , Factores de Edad , Anaerobiosis , Animales , Arginina/metabolismo , Metabolismo Energético , Concentración de Iones de Hidrógeno , Mariposas Nocturnas/parasitología , Resonancia Magnética Nuclear Biomolecular , Compuestos Organofosforados/metabolismo , Isótopos de Fósforo , Especificidad por Sustrato
12.
J Parasitol ; 81(3): 434-8, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7776130

RESUMEN

Phosphorus resonances consistent with phosphoarginine and ATP were observed in the in vivo 31P-nuclear magnetic resonance (NMR) spectra of infective larvae of Haemonchus contortus. The level of phosphoarginine quickly declined when nematode suspensions were purged with nitrogen and was restored upon return to aerobic conditions. Saturation transfer NMR demonstrated forward and reverse exchange of phosphorus between phosphoarginine and ATP.


Asunto(s)
Adenosina Trifosfato/metabolismo , Arginina/análogos & derivados , Haemonchus/metabolismo , Aerobiosis , Anaerobiosis , Animales , Arginina/metabolismo , Larva/metabolismo , Espectroscopía de Resonancia Magnética , Nitrógeno/metabolismo , Compuestos Organofosforados/metabolismo , Oxígeno/metabolismo
13.
Water Sci Technol ; 48(10): 33-8, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-15137150

RESUMEN

This study gives a review on the process of identification of significant pressures and impacts, which is an important part of river basin planning and in particular for implementing the EU Water Framework Directive (WFD) (2000/60/EC). The questions: what is a "significant pressure" in terms of the WFD? which sources and driving forces have to be regarded? which data can be used? which pressure on a water body is significant? and which implications and requirements result from the identification process?--should be considered. The European Commission requires reporting from all Member States about the status of the water bodies within a river basin district and about the risk of failing the environmental objectives by the end of 2004. Therefore, a number of prevailing projects across Europe aim to develop a guideline on a common understanding of the most effective approach towards the identification of significant anthropogenic pressures, and the analysis of potential impacts including the identification of appropriate tools and models. In such a guideline suitable and intelligent criteria have to be developed in order to enable a uniform assessment of the anthropogenic pressures within a river basin district.


Asunto(s)
Modelos Teóricos , Ríos , Contaminación del Agua/análisis , Contaminación del Agua/prevención & control , Abastecimiento de Agua , Monitoreo del Ambiente , Europa (Continente) , Factores de Riesgo
14.
Water Sci Technol ; 43(5): 41-9, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11379155

RESUMEN

A case study on the application of the River Water Quality Model No. 1 (RWQM1) is presented in order to illustrate the importance of modelling a sediment compartment for an ecologically meaningful assessment of the impact of wastewater effluents and combined sewer overflows. The focus of this case study is on the compartmentalisation approach of the RWQM1 that makes such a description possible. In contrast to this, a strongly simplified biochemical submodel is used that considers only oxygen and dissolved substrate. The object of the case study is the River Lahn, a moderately polluted 5th order stream in Germany, for which the connectivity of surface/subsurface flows and mass fluxes within river sediments have been intensively investigated. The hyporheic flow between a downwelling and upwelling zone of a riffle-pool sequence has been studied with the aid of tracer experiments and continuous records of water constituents. High diurnal fluctuations of oxygen travelled to considerable depth of the sediment and oxygen in the interstitial water decreased considerably while travelling through the riffle. Starting with the implementation of a strongly simplified version of the biochemical part of the RWQM1, but with the consideration of a sediment pore water compartment in addition to the water column compartment, a calibration procedure is performed using tracer data from the water column and the sediment. The calibrated model is then used to study the system response to wastewater treatment plant effluent and combined sewer overflow emissions. The modelling approach makes it possible to quantify the sediment oxygen demand and the spatial and temporal extent of sediment zones with oxygen depletion. However, the spatially averaged approach does not account for inhomogeneities in the sediment. It is shown that for this river with its alluvial coarse sediments even moderate emissions from sewerage systems may be high enough to drop sediment oxygen concentrations to low levels while those in the surface flow remain close to saturation. Similarly, it is demonstrated that combined sewer overflows may cause anoxic sediment oxygen conditions for extended time periods. The implications for ecologically sound river water quality modelling and for specific quality objectives are discussed.


Asunto(s)
Eutrofización , Modelos Teóricos , Oxígeno/metabolismo , Eliminación de Residuos , Contaminación del Agua , Fenómenos Bioquímicos , Bioquímica , Ecosistema , Sedimentos Geológicos/química , Hipoxia , Oxígeno/análisis , Aguas del Alcantarillado , Solubilidad
15.
Water Sci Technol ; 43(5): 1-9, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11379119

RESUMEN

Successful river water quality modelling requires the specification of an appropriate model structure and process formulation. Both must be related to the compartment structure of running water ecosystems including their longitudinal, vertical, and lateral zonation patterns. Furthermore, the temporal variability of abiotic boundary conditions may be important and must be incorporated by an appropriate choice of model parameters. A six-step decision procedure is proposed to achieve these objectives. The steps address the determination of the following model features: (1) temporal representation (dynamic or steady-state); (2) model dimensionality; (3) mixing; (4) advection; (5) reaction terms; and (6) boundary conditions. Numerical criteria based on process time constants and length scales provide a basis for these decisions.


Asunto(s)
Modelos Teóricos , Contaminación del Agua , Toma de Decisiones , Factores de Tiempo , Movimientos del Agua
16.
Water Sci Technol ; 43(5): 11-30, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11379121

RESUMEN

In this paper, biochemical process equations are presented as a basis for water quality modelling in rivers under aerobic and anoxic conditions. These equations are not new, but they summarise parts of the development over the past 75 years. The primary goals of the presentation are to stimulate communication among modellers and field-oriented researchers of river water quality and of wastewater treatment, to facilitate practical application of river water quality modelling, and to encourage the use of elemental mass balances for the derivation of stoichiometric coefficients of biochemical transformation processes. This paper is part of a series of three papers. In the first paper, the general modelling approach is described; in the present paper, the biochemical process equations of a complex model are presented; and in the third paper, recommendations are given for the selection of a reasonable submodel for a specific application.


Asunto(s)
Eutrofización , Modelos Teóricos , Contaminación del Agua , Bacterias Aerobias , Hipoxia , Nitrógeno/metabolismo , Oxígeno/metabolismo , Aguas del Alcantarillado
17.
Water Sci Technol ; 43(5): 31-40, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11379147

RESUMEN

The new River Water Quality Model no. 1 introduced in the two accompanying papers by Shanahan et al. and Reichert et al. is comprehensive. Shanahan et al. introduced a six-step decision procedure to select the necessary model features for a certain application. This paper specifically addresses one of these steps, i.e. the selection of submodels of the comprehensive biochemical conversion model introduced in Reichert et al. Specific conditions for inclusion of one or the other conversion process or model component are introduced, as are some general rules that can support the selection. Examples of simplified models are presented.


Asunto(s)
Eutrofización , Modelos Teóricos , Contaminación del Agua , Fenómenos Bioquímicos , Bioquímica , Toma de Decisiones , Nitrógeno/metabolismo , Oxígeno/metabolismo , Aguas del Alcantarillado
18.
Dement Geriatr Cogn Dis Extra ; 3(1): 301-11, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24174925

RESUMEN

BACKGROUND/AIMS: Many studies have shown that not only pharmacological treatment but also cognitive stimulation in the early stages of Alzheimer's disease (AD) improves language processing and (other) cognitive functions, stabilizes Activities of Daily Living (ADL) and Instrumental Activities of Daily Living (IADL) functions and increases the subjective quality of life (wherein a combination of pharmacological intervention and cognitive stimulation could provide greater relief of clinical symptoms than either intervention given alone). Today, it is no longer the question of whether cognitive stimulation helps but rather what kind of stimulation helps more than others. METHODS: A sample of 42 subjects with mild AD (all medicated with an acetylcholinesterase inhibitor and well adjusted) underwent clinical and cognitive evaluation and participated in a 6-month study with 2 experimental groups (i.e. 'client-centered' global stimulation vs. cognitive training) and a control group. Since the test performance also depends on the individual test, we used a wide variety of tests; we z-transformed the results and then calculated the mean value for the global cognitive status (using the Mini-Mental State Examination) as well as for the single functional areas. RESULTS: Between-group differences were found, they were overall in favor of the experimental groups. Different functional areas led to different treatment and test patterns. Client-centered, global, cognitive therapy stimulated many cognitive functions and thus led to a better performance in language processing and ADL/IADL. The subjective quality of life increased as well. The cognitive training (of working memory) improved only the ADL/IADL performance (more, however, than client-centered, global, cognitive stimulation) and stabilized the level of performance in the other three functional areas. © 2013 S. Karger AG, Basel.

20.
Fortschr Neurol Psychiatr ; 60(10): 383-92, 1992 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-1427555

RESUMEN

From the clinical point of view, substance-induced psychosis can be rather similar to schizophrenia. However, the question whether phenomenological resemblances represent similar underlying causal mechanisms is unsolved. Whereas the interest in experimentally induced psychosis was purely academic until the mid-1960s, the widespread use of "recreational" drugs provided this research with an important practical impact. With respect to a given case the differential diagnosis between schizophrenia and drug-induced psychosis it is often problematic. The differences in psychopathology refer to the disturbances of experience in general (Ichstörungen), the character of the hallucinations and the quality and quantity of the alterations of consciousness. Contrary to the sharp distinctions which used to be drawn between schizophrenia and drug-induced psychotic states, we hold that these states are rather similar, and may even represent a common underlying pathology. Hence, the renewed interest in the study on experimentally induced psychotic states using advanced methodology seems justified.


Asunto(s)
Drogas Ilícitas/efectos adversos , Psicosis Inducidas por Sustancias/diagnóstico , Psicotrópicos/efectos adversos , Esquizofrenia/diagnóstico , Psicología del Esquizofrénico , Diagnóstico Diferencial , Humanos , Escalas de Valoración Psiquiátrica , Psicosis Inducidas por Sustancias/psicología , Esquizofrenia/inducido químicamente
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