Search

Fuel sloshing-induced damping is currently being studied extensively within the EU-funded SLOWD project as a means of passively reducing dynamic loads in aircraft wings. It is of interest to be able to determine which parameters have the greatest influence on the added damping from the sloshing motion. An uncertainty in the measured sloshing force has been observed when multiple consecutive and identical oscillation cycles are considered in sinusoidal excitation experiments, leading to variations in the measured energy dissipation. This current work considers liquid undergoing vertical sloshing motions for different fill level and excitation conditions (frequency and amplitude) leading to energy dissipation via several possible physical mechanisms. The sloshing dissipation is measured experimentally across a large number of excitation cycles and for each excitation amplitude, expressed in the form of Froude (Fr) numbers. Depending on the Fr number, distinct sloshing mechanisms dominate the dissipative effects and induce a particular variance across the identical cycles analysed. The sloshing-induced energy dissipation variation is quantified and correlated with different mechanisms depending on Fr number, helping to explain various non-stationary effects that are observed even in well-controlled experimental conditions. As well as improving the insights into the inherent dispersion nature of the studied phenomena, this research also establishes experimental characteristics suitable for future model validation and calibration.

Tillage practices affect soil water and nitrogen supply to bread wheat grown under rainfed conditions. It may, therefore, affect grain yields and 13C/12C ratio or δ13C, expressed as Δ13C discrimination in photosynthesis and δ15N natural abundance by the wheat crop. To assess whether Δ13C and δ15N natural abundance can be used to evaluate the tillage and N use effects on wheat crop yield, N uptake, and nitrogen use efficiency (NUE), we examined the δ15N and Δ13C values of wheat dry matter at anthesis and grain sampled at harvest from conventional till (CT) and no-till (NT) treatments, with 0 and 75 kg N ha−1 applied annually over 5 years to account for seasonal rainfall variability. Wheat grain yields were higher under the NT practice than the CT practice and with N application, and showing significant year × tillage, year × N, tillage × N interactive effects on grain yields. Anthesis dry matter δ15N values and wheat grain δ15N values were closely correlated. Grain δ15N differed significantly among years. Wheat under NT practice had lower δ15N than the CT practice, indicating increased N utilisation by the crop under the NT practice. Grain NUE varied from 0 to >66% over the 5-year period and tended overall to be higher under NT (34%) than the CT practice (28%). Grain NUE was closely correlated with water use efficiency (WUE) and crop water use by bread wheat. It was estimated that by increasing grain WUE from 8 kg ha−1 mm−1 to 12 kg ha−1 mm−1, the grain NUE increased from 21% to 47%. The δ15N values of the wheat crop can be used to distinguish total N uptake from applied N fertiliser and soil derived N. Also, the NUE × WUE interactions can be discerned by Δ13C values of the grain in bread wheat in a semi-arid rainfed environment.

In this paper, a variable structure control strategy is adopted to improve position accuracy of Diamond 600k, a 2-Dof parallel manipulator. Firstly, mechanism and servomotor dynamics are developed in terms of the virtual work principle, while the mechantronics coupling model of the manipulator is formulated according to the equivalent torque. At this stage, the mass matrix of the mechanism is calculated individually to decouple the systematic model. This can effectively reduce the computational burden of the dynamic model in the real time control process. Then, various path-planning methods are compared with each other in order to explore which of them is more suitable to the high-speed manipulator. Last, results of the relevant experiments and simulations are presented from which it is easily can be seen that in comparison to conventional PID controller, the algorithm developed in this paper provides more reliable tracking performance.

Depleted soil nitrogen supplies in long-term continuously cultivated soil for cereal grain cropping have resulted in reduced cereal yields, low grain proteins and hence low economic returns. This has necessitated the development of alternative management practices to sustain crop yields, as well as to restore and maintain soil fertility. In the present study we examined the comparative performance of several management options over a 12-year period, including: a 4-year rotation of grass + legume pasture followed by wheat (GL–wheat); 2-year rotations of lucerne–wheat, annual medic–wheat and chickpea–wheat; and continuous conventional tillage (CT) or no-tillage (NT), without or with fertiliser N application (0, 25 and 75 kg N ha–1 for each crop). Average wheat grain yields were highest in the chickpea–wheat rotation, followed by the NT wheat with 75 kg N ha–1; the lowest grain yields were in the CT or NT wheat treatment without fertiliser N application. Crop water use and gross margin were strongly correlated. However, there was an increasing potential for the deep leaching of nitrate-N at 75 kg N ha–1 application, as well as from the GL pasture initiated in 1987, but not from that initiated in 1986, emphasising the effect of variability in growing seasons. Soil organic C stocks increased under the 4-year GL pasture in the 0–0.1 m depth only, then decreased steadily following the cropping phase. The rotation of 4-year GL pasture followed by wheat cropping for 4–6 years may maintain initial soil organic C stock, but a shorter cropping phase is required to increase soil organic C and N stocks and soil fertility in the long term. Partial economic analysis of the treatments suggested that restoring or maintaining soil N fertility, either through legume-based pastures, grain legume and/or N fertiliser, provides long-term positive economic return.

Summary Results from the pioneering research on the interactions between pH and denitrification in soil from the 1950s to the present are reviewed, the changing perceptions of this complex relationship are discussed, and the current status of the subject is assessed. Facets of this relationship that are analysed in detail include the direct or indirect influence of pH on overall denitrification rates in soils, changes in the composition of gaseous products that depend on pH, methods for measuring the process, the concept of an optimum pH for denitrification, and the adaptation of microbial denitrifying communities to acidic environments. The main conclusions to be drawn are as follows. Total gaseous emissions to the atmosphere (N2O, NO and N2) have repeatedly been shown to be less in acidic than in neutral or slightly alkaline soils. This may be attributable to smaller amounts of organic carbon and mineral nitrogen available to the denitrifying population under acid conditions rather than a direct effect of low pH on denitrification enzymes. Numerous laboratory and field studies have demonstrated that the ratio N2O:N2 is increased when the pH of soils is reduced. The relation between soil pH and potential denitrification as determined by various incubation methods remains unclear, results being influenced both by original conditions in soil samples and by unknown changes during incubation. The concept of an optimum pH for denitrification has been frequently proposed, but such a term has little or no meaning without reference to specific attributes of the process.

The prompt detection and effective management of infectious disease in wildlife rely greatly on field diagnosis. Although clinical work is sometimes of value, the cornerstone of diagnosis is pathological examination (gross necropsy with supporting laboratory investigations). The approach and rationale to gross post-mortem examination are common to all species, despite possible significant differences in technique. Likewise, the principles of sampling are usually comparable, with emphasis on standardisation, the correct use of equipment, and consistency in methods of storage and transportation of specimens. However, the type of sample taken and the laboratory tests required differ, depending upon the circumstances and possible diagnosis. Retention of material is always important. The principles of diagnostic pathology are discussed, with reference to selected diseases, namely: mycobacteriosis, Rift Valley fever, rabies, spongiform encephalopathies, morbillivirus and poxvirus infections, viral encephalitides, West Nile virus infection and chytridiomycosis. The importance of being able to perform certain investigations in the field, efficiently and safely, is emphasised.

BackgroundThere are no published reports of cross-cultural equivalence and interrater reliability at the level of individual symptom items assessed by a semi-structured clinical interview employing operationalised clinician ratings.AimsTo assess the cross-cultural clinical equivalence and reliability of a Chinese version of the World Health Organization Schedules for Clinical Assessment in Neuropsychiatry (SCAN).MethodUK-US and Taiwanese groups of psychiatrists used Chinese and English transcripts of videotape interviews of Taiwanese patients to discuss cross-cultural issues and ratings of SCAN items. Item ratings were compared quantitatively individually and pooled by SCAN section.ResultsChinese equivalents were found for all SCAN items. No between-group differences were found for most individual items, but there were differences for some scaled items. Average agreement between the two groups was 69–100%.ConclusionsCross-cultural implementation based on SCAN in Taiwan appears valid.

One hundred years ago (January 5th, 1901), an article in the Veterinary Record declared: The use of chloroform by practitioners is now common, and the amount of pain and suffering prevented is enormous. By its aid we are enabled to perform operations with success which without it were seldom satisfactory. A century later, in an age of sophisticated veterinary medicine, those words seem quaint, a relic of a bygone age. Our understanding of anesthesia of invertebrates in 2000 is very much at a comparable stage, however, and a great deal of research is needed to remedy this situation.

Analysis of the flavonoid content of seed and root exudates of Lotus pedunculatus was undertaken using multiple coupled analytical techniques: capillary zone electrophoresis coupled to a UV spectral array detector (CZE-UV), high performance thin-layer chromatography with densitometry (HPTLC-UV) and gas chromatography with mass spectrometry (GC-MS). These procedures provided separation, identification and structural confirmation of the previously unidentified flavonoids in this plant's seed and root exudates and were particularly applicable to samples from a small seeded legume. Catechin, naringenin, kaempferol, quercetin aglycone and 3 different glycosides of quercetin were detected in seed exudate. Sterile root exudates contained catechin, naringenin and quercetin in addition to apigenin, kaempferol and other flavones and flavanones for which partial identifications were obtained. When sterile root exudate was incubated with Mesorhizobium loti, changes in its flavonoid content were detected. Analysis of bacterial cells after incubation revealed the presence of quercetin, kaempferol and one other flavone. The monocyclic aromatics protocatechuic acid and phloroglucinol were detected in both the incubated root exudate and its bacterial cells.

Investigations of free-living wild animals often involve capture, restraint or other forms of manipulation. There is a need, on both scientific and welfare grounds, to develop and to use less invasive techniques, especially for the assessment of health. Already some such procedures exist, ranging from observation of clinical signs to the laboratory examination and analysis of faeces and other naturally voided samples.Minimally invasive and non-invasive health monitoring of vertebrate animals is outlined and examples are given of samples from mammals, birds, reptiles, amphibians and fish that can provide useful information.

Detailed individual nodulation profiles were obtained for five strains of Rhizobium leguminosarum biovar trifolii inoculated onto roots of Trifolium repens seedlings growing on an agar medium of pH 4.5. The time of appearance and the location of every nodule were noted for a period of 10 days after inoculation. Using these nodulation frequency profiles, pairings of strains were identified and six mixed-strain inoculation (1:1 ratio) experiments were subsequently performed at pH 4.5. Results from the mixed-inoculum experiments showed that the performance of a Rhizobium strain in single culture could not be reliably used to predict the outcome of a paired-inoculation study and that some seedlings were exclusively nodulated by rhizobia that performed poorly at low pH in single-culture inoculations.

The fate of 14C-naringenin during its specific activation of nod genes in Rhizobium leguminosarum bv. viciae was examined. After incubation with either strain RBL5560 or its pSym-cured derivative in a medium supplemented with 14 C-naringenin at nod gene-inducing concentrations of 2 nM (ca. 12.5 kBq) plus cold acetate (0.5 μM), a radiocarbon inventory for the cells and supernatant extracts was obtained. The level of 14 C-label incorporation was also determined in the fractionated cellular components. Using 14 C-acetate at 0.5 μM (1036 kBq) and cold naringenin (2 nM) in incubations with strain RBL5560 as a separate treatment, the Nod metabolites were detected by thin layer and high performance liquid chromatographic methods and the data provided the basis for identification of the Nod factors from the supernatant obtained from 14 C-naringenin treatments. Subsequent radio-biochemical and chemical analyses revealed that RBL5560 cells assimilated 14 C-naringenin during the activation of nod genes. Our analysis also showed that labelled carbon atoms from the 14 C-naringenin were incorporated into the acyl moiety of a lipo-oligosaccharide Nod factor, NodRlv IV, present in the culture supernatants of RBL5560. The pSym-cured derivative failed to synthesize any Nod metabolites in a 14 C-naringenin supplemented medium. The tracing of flavonoid-derived carbon atoms to the acyl chain of a host-specific Nod factor, a moiety that defines host specificity for this Rhizobium, adds a new dimension to the signalling function of flavonoids in legume-Rhizobium interactions.

Objective : In preparing for the publication of ICD-10, the Division of Mental Health of the World Health Organization developed several versions of chapter V, which deals with mental and behavioral disorders. The version for research purposes is called the Diagnostic Criteria for Research (ICD-10 DCR) and gives operational criteria for the diagnosis of mental disorders. This article describes the results of international field trials undertaken to evaluate the draft criteria and refine them further. Method : Data were obtained to assess interrater agreement, the confidence with which diagnoses could be made, and the ease of use of the criteria. Additional substudies examined the concordance between ICD-10 DCR, ICD-10 Clinical Descriptions and Diagnostic Guidelines, and other national classification systems (e.g., DSM-IV). The field trials were carried out at 151 clinical centers in 32 countries by 942 clinician/researchers who conducted 11,491 individual assessments of patients. Results for cases assessed by at least two raters are reported here. Results : Most clinician/researchers found the criteria to be explicit and easy to apply. Interrater agreement was high for most diagnostic categories. For some categories, such as those dealing with certain polymorphic psychotic disorders or milder forms of affective disorders, the criteria were rated as somewhat difficult to use, and reliability was lower. Comparison of the results of these field trials with those of the ICD-10 Clinical Descriptions and Diagnostic Guidelines demonstrated that there are increases in interrater agreement when the operational criteria are used. Conclusions : The use of internationally accepted research criteria enhances the reliability of diagnosis of mental disorders made in research settings worldwide.

The Lough Neagh catchment area covers about one-third of the land area of Northern Ireland. This report documents NO 2 - concentrations in the major rivers entering Lough Neagh, which are frequently in the range of 100 to 150 μg N L -1 and exceed the European Community (EC) water quality guide values. The contribution of land drainage to NO 2 - loads carried by these rivers was estimated to be about 40%. The remaining 60% of NO 2 - appears to originate from N transformations at the sediment-water interface of the river system. The available evidence suggests that NH 4 + originating from agricultural pollution provides the N substrate for nitrification by Nitrosomonas to NO 2 - . What is anomalous is why this NO 2 - is not further oxidized rapidly to NO 3 - by Nitrobacter. A possible mechanism is that the Nitrobacter is retarded by the presence of free ammonia concentrations that can be predicted to be present in the range of 65 to 76 μg N L -1 .

Concentrations of NO2−N in land drainage and river waters in Northern Ireland in recent years have frequently exceeded EEC guide values. Very little information exists to indicate if and when NO2− accumulates in soil solution, and whether NO2− from the soil profile is the source of NO2− in drainage and river waters. The occurrence of NO2− in the field was studied and laboratory incubation experiments carried out to determine the possible sources of NO2− in grassland soil. Field studies were carried out to determine the occurrence and spatial variability of NO2− in a grazed, grassland soil. Plots receiving either 100 or 500 kg N ha−1 yr−1 were systematically sampled in May and October 1992. Concentrations of NO2− in soil were highly variable and ranged from 0 to 2.747 μg N g−1, the data being significantly skewed to the right. Correlation matrices and stepwise multiple regression analyses showed relationships between NO2− and a number of soil variables. Nitrite appeared to be related to variables which indicated its occurrence as a result of nitrification of either fertilizer- or urine-derived NH4+. Nitrate was repeatedly correlated to NO2− concentrations, suggesting that both nitrification and nitrate reduction may be responsible for NO2− formation. Spatially, nitrite occurred at random, basic geostatics producing only one variogram, showing an increase in NO2− concentrations with an increase in distance between sampling points. There was no pattern to the distribution of NO2− with depth, indicating differences in the ratios of the rates of NO2− production and consumption. Numbers of NH3-oxidizers were consistently higher than numbers of NO2−-oxidizers, with some degree of variation between samples. The microbial aspects of NO2− formation are discussed, including partial recycling of NO2− via the NO3− pool, and possible causes of NO2− accumulation due to the inhibition of NO2−-oxidizing bacteria. Laboratory incubation studies were carried out in which measurable NO2− flushes were induced. Increasing soil pH and NH4+ concentrations produced large NO2− flushes, which peaked after about 17 days of incubation, then rapidly declined. Soil incubated with urea produced NO2−N concentrations equivalent to those encountered in the field, suggesting that NH4+ oxidation accounts for a significant proportion of NO2− formed in this soil.

Soil incubation studies were undertaken in controlled environment cabinets at 15°C to investigate the effect of increasing application rates of calcium ammonium nitrate (CAN) on net nitrification in two grassland soils. Granular CAN was applied to the surface of freshly collected, moist soil, at a rate equivalent to 0, 100, 200, 400, 800 and 1600µg NH 4 + -N and NO 3 - -N per gram of oven dry soil. In half the treatments finely ground CaCO3 was incorporated into the moist soil to raise the starting pH. Changes in soil mineral N and pH were measured at weekly intervals up to six-weeks. The most probable number (MPN) technique was used to enumerate the NH 4 + -N and NO 2 - -N oxidizers at the beginning and end of the incubation. At low rates of CAN application there was considerable NH 4 + -N oxidation to NO 3 - -N during the incubation of both soils. Lime stimulated this N transformation. At high application rates (i.e. 800 and 1600 ppm) there was little change in NH 4 + -N or NO 3 - -N on either soil during the 6 week incubation, in the presence or absence of lime. The rate of NO 3 - -N produced peaked at 5.6 and 3.8 mg NO 3 - -N kg−1 d−1 on soil 1 and 2 respectively, in the presence of lime. Above a level of 400 ppm CAN (equivalent to 38 kg N ha−1) the rate of NO 3 - -N produced decreased. The higher rate of net nitrification in soil 1 compared with soil 2 was probably due to a higher number of nitrifying bacteria. Although high rates of CAN decreased the nitrifying activity of both soils there was little difference between treatments in the actual numbers of NH 4 + -N and NO 2 - -N oxidizers determined by the MPN technique. The results showed that the rate of granular CAN applied to the soil surface can influence the local activity of nitrifying bacteria and subsequent N transformations. At application rates of CAN generally used agriculturally for grass production, it is likely that net nitrification of the NH 4 + -N in the fertilizer granule will be inhibited.

Publisher Summary Biological nitrogen fixation (BNF) is an important N supply route for both natural vegetation and crop plants. The biological reduction of N− to NH× ιν τηισ προψeσσ takes place at ambient temperature and subambient pressure and is performed by prokaryotes possessing the nitrogenase enzyme. Symbionts are the most significant N fixers for plants, and they are represented primarily by rhizobia (Protobacteria), Frankia (Actinomycetes), and Nostoc/Anabaena (Cyanobacteria). These organisms reside in specialized structures where they have access to a plentiful energy source in the form of photosynthates and an environment that is conducive both to nitrogenase activity and the translocation of fixed N directly to the host plant. Legumes have a special position among agricultural plants, as they have the ability to capture (fix) atmospheric N− through the presence of rhizobia in root nodules, which makes their growth theoretically independent both of soil N status and extraneous fertilizer N addition. Nutrient deficiencies can adversely affect legume root nodule symbioses at a very early stage of development, and the essential nutrients required by rhizobia are those with a direct involvement in the structure and metabolic functioning of the microbial cell. Phosphorus has an essential function in the energy metabolism of plants and thus plays an important role in N− fixation due to the high ATP demand from the nitrogenase reaction. High Ca supply, on the other hand, increases the number of nodules and the amount of nod gene-inducing compounds in root exudates. Sulfur deficiency may also decrease N− fixation by affecting nodule development and function, reduce leghemoglobin concentration in nodules, and lower ATP concentrations in bacteroids as well as in mitochondria of root nodules.

A combined subtraction hybridization and polymerase chain reaction/amplification technique was used to develop a DNA probe which was specific for the Rhizobium leguminosarum biovar phaseoli and the Rhizobium tropici group. Total genomic DNA preparations from Rhizobium leguminosarum biovar viciae, Rhizobium leguminosarum biovar trifolii, Rhizobium sp., Agrobacterium tumefaciens, Rhizobium fredii, Bradyrhizobium japonicum, Bradyrhizobium ssp. and Rhizobium meliloti were pooled and used as subtracter DNA against total genomic DNA from the Rhizobium leguminosarum biovar phaseolo strain KIM5s. Only one round of subtraction hybridization at 65°C was necessary to remove all cross-hybridizing sequences. Dot blot hybridizations with total genomic DNA of the eight subtracter organisms and 29 bacteria of different groups confirmed the high specificity of the isolated DNA sequences. Dot blot hybridizations and total genomic DNA from ten different R. Leguminosarum biovar phaseoli and R. tropici strains resulted in strong hybridization signals for all strains tested. The DNA probe for the R. tropici and R. leguminosarum biovar phaseoli group was used for dot blot hybridization with DNA extracts from three tropical and one boreal soil. When correlated with data from Most Probable Number analyses the probe was capable of detecting as low as 3 × 104 homologous indigenous rhizobia per g soil. The technique offers great benefits for the development of DNA probes for monitoring bacterial populations in environmental samples.

Since the first volume of Bergey's Manual of Systematic Bacteriology was published, in 1984, two additional genera and several new species of stem- and root-nodulating bacteria have been proposed; further changes to the taxonomy of this group of organisms appear likely. This paper briefly reviews the current status of “Rhizobium” taxonomy and proposes minimal standards for the description of future genera and species belonging to this group of organisms.

Release of soluble reactive phosphorus (SRP) from dissolved organic phosphorus (DOP), concentrated by reverse osmosis of water samples from Lough Neagh Northern Ireland, was measured in the presence of enzymes and cultures of lake water bacteria in a basal liquid medium adjusted to the pH of lake water (7.6). No hydrolysis of unfractionated DOP was observed in the presence of alkaline phosphatase but a combination of alkaline phosphatase and phosphodiesterase mineralized 14% of DOP in a 30 day incubation period at 15 °C. A similar amount of mineralization was attained by phytase. Phytase induced the same degree of mineralization in a range of DOP fractions varying from MW > 100 000 to c. 500. A mixed culture of lake water bacteria mineralized 12% of unfractionated DOP. Single cultures of lake water bacteria displayed low mineralizing activity (mean of 49 cultures = 5% DOP hydrolysed). Results indicate that DOP from Lough Neagh in the above molecular weight range is predominantly recalcitrant to bacterial mineralization under natural lake conditions.

The ability to track time varying frequency and damping parameters using on-line versions of seven time domain system identification algorithms; Least Squares, Double Least Squares, Correlation Fit, Instrumental Variables, Instrumental Matrix with Delayed Observations, Extended Least Squares and Maximum Likelihood, is examined. Comparisons are made on results obtained from data generated from various simulated time varying systems, corrupted with both input and measurement noise, as a preliminary step before advancing onto real data. Only the Maximum Likelihood and Double Least Squares methods gave acceptable results on the most difficult data sets that were considered. The choice of an exponential weighting factor is crucial to the performance of the on-line methods when applied to data from time varying systems. The effect of assigning various values of the weighting factor is demonstrated. Further work is required to determine the optimum schemes for defining this parameter.

The exchange of chemical signals between soil bacteria (rhizobia) and legumes has been termed a molecular dialogue. As initially conceived in the early 1990s, it involved two main groups of molecules: nod gene-inducing flavonoids from plants and the mitogenic lipochito-oligosaccharide Nod factors of rhizobia. This review considers how subsequent research revealed the existence of a more complex set of interactions, featuring expanded roles for the original participants and contributions from additional plant and bacterial metabolites. Rhizobia respond to chemoattractants and growth-enhancing compounds in root exudates, and several plant nonflavonoids possess nod gene-inducing properties. Expression of non-nod genes is induced by flavonoids; these include encoders of a type I secreted protein and the entire type III, and possibly also type IV, secretion systems. Many other genes and proteins in rhizobia are flavonoid-inducible but their functions are largely unknown. Rhizobia produce far more Nod factor variants than was previously envisaged and their structures can be influenced by the pH of the environment. Other symbiotically active compounds or systems of rhizobia, some of them universally present, are: the surface polysaccharides, quorum-sensing N-acyl homoserine lactones, plant growth-promoting lumichrome and two-component regulatory systems.

The prompt detection and effective management of infectious disease in wildlife rely greatly on field diagnosis. Although clinical work is sometimes of value, the cornerstone of diagnosis is pathological examination (gross necropsy with supporting laboratory investigations). The approach and rationale to gross post-mortem examination are common to all species, despite possible significant differences in technique. Likewise, the principles of sampling are usually comparable, with emphasis on standardisation, the correct use of equipment, and consistency in methods of storage and transportation of specimens. However, the type of sample taken and the laboratory tests required differ, depending upon the circumstances and possible diagnosis. Retention of material is always important. The principles of diagnostic pathology are discussed, with reference to selected diseases, namely: mycobacteriosis, Rift Valley fever, rabies, spongiform encephalopathies, morbillivirus and poxvirus infections, viral encephalitides, West Nile virus infection and chytridiomycosis. The importance of being able to perform certain investigations in the field, efficiently and safely, is emphasised.

Die traditionelle Zweiteilung der funktionellen Psychosen in Schizophrenien und manisch depressive Psychosen last sich auf akute psychotische Storungen, die einen abrupten Beginn, eine kurze Dauer und gute Prognose, jedoch keine organische Ursache aufweisen, nicht zufriedenstellend anwenden. Diese Storungen werden jetzt sowohl in der ICD-io als auch im DSM-IV als eigenstandig neben den schizophrenen Syndromen und affektiven Psychosen anerkannt. Das zeigt die weitgehende internationale Ubereinstimmung daruber, das diese Beschwerdebilder uber ein hinreichendes Mas an Eigenstandigkeit als beschreibbare klinische Zustande verfugen. Jedoch wird in beiden Klassifikationen die Einordnung lediglich als „Storung” vorgenommen, d.h. als Gruppe von Symptomen und Verhaltensweisen, die „klinisch erkennbar“ (ICD-10) oder „klinisch bedeutsam” (DSM-IV) sind. Bis jetzt ist zu wenig uber ihre Atiologie, ihre Genetik oder die Mechanismen und Prozesse bekannt, die den Symptomen zugrunde liegen, um dieses Beschwerdebild von seinem bescheidenen Status als klinische Storung zu einer anerkannten Krankheitsentitat befordern zu konnen.