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Investigations on intra- and interannual coarse sediment dynamics in a high-mountain catchment
(2011)
Unspecific peroxygenases (UPO; EC 1.11.2.1) represent a group of secreted heme-thiolate proteins that are capable of catalyzing the mono-oxygenation of diverse organic compounds, using only H2O2 as a co-substrate. Here we show that the four peroxygenases AaeUPO, MroUPO, rCciUPO and rNOVO catalyze the stepwise hydroxylation of cyclohexane to cyclohexanol and cyclohexanone. The catalytic efficiencies (kcat/Km) for the initial hydroxylation were in the same order of magnitude for all four peroxygenases (∼104 M−1 s−1), whereas they differed in the second step. The conversion of cyclohexanol by AaeUPO and rCciUPO was 1–2 orders of magnitude less efficient (∼102 M−1 s−1) than by MroUPO and rNOVO (∼104 M−1 s−1). The highest conversion rate in terms of H2O2 utilization was accomplished by MroUPO under repeated addition of the peroxide (87% in relation to the total products formed). Using the latter UPO, we successfully established a micro-mixing reaction device (SIMM-V2) for the oxidation of cyclohexane. As cyclohexanone is a chemical of high relevance, for example, as starting material for polymer syntheses or as organic solvent, new enzymatic production pathways for this compound are of interest to complement existing chemical and biotechnological approaches. Stable and versatile peroxygenases, as those presented here, may form a promising biocatalytic platform for the development of such enzyme-based processes.
The catalase activity of three unspecific peroxygenases (UPOs) from the agaric basidiomycetes Agrocybe aegerita, Coprinopsis cinerea and Marasmius rotula was investigated. The study included analysis of pH dependency of the catalase reaction and H₂O₂ mediated enzyme inactivation as well as experiments on the influence of a second substrate on the course of catalase reaction. Apparent kinetic parameters (Km, kcat) for the catalase activity of UPOs were determined. Inactivation of UPOs by H₂O₂ is discussed with regard to O₂ production and remaining UPO activity. Furthermore formation of biliverdin as heme destruction product was demonstrated along with the formation of UPO compound III as a possible intermediate that forces the destruction process. Radical trapping experiments with methyl benzoate gave indication for the formation of hydroxyl radicals in the presence of excess H₂O₂. Eventually, a plausible pathway of heme destruction has been proposed, proceeding via UPO compound III and subsequent hydroxyl radical formation, which in turn may cause heme bleaching and verdoheme and biliverdin formation.
Assessment of subjective workload in an anaesthesia simulator environment: reliability and validity
(2011)
Unspecific peroxygenases (UPOs) are secreted fungal enzymes with promiscuity for oxygen transfer and oxidation reactions. Functionally, they represent hybrids of P450 monooxygenases and heme peroxidases; phylogenetically they belong to the family of heme-thiolate peroxidases. Two UPOs from the basidiomycetous fungi Agrocybe aegerita (AaeUPO) and Marasmius rotula (MroUPO) converted 35 out of 40 compounds listed as EPA priority pollutants, including chlorinated benzenes and their derivatives, halogenated biphenyl ethers, nitroaromatic compounds, polycyclic aromatic hydrocarbons (PAHs) and phthalic acid derivatives. These oxygenations and oxidations resulted in diverse products and-if at all-were limited for three reasons: (i) steric hindrance caused by multiple substitutions or bulkiness of the compound as such (e.g., hexachlorobenzene or large PAHs), (ii) strong inactivation of aromatic rings (e.g., nitrobenzene), and (iii) low water solubility (e.g., complex arenes). The general outcome of our study is that UPOs can be considered as extracellular counterparts of intracellular monooxygenases, both with respect to catalyzed reactions and catalytic versatility. Therefore, they should be taken into consideration as a relevant biocatalytic detoxification and biodegradation tool used by fungi when confronted with toxins, xenobiotics and pollutants in their natural environments.
Structural engineering of topological bulk materials is systematically explored with regard to the incorporation of the buckled bismuth layer [Bi₂], which is a 2D topological insulator per se, into the layered BiTeI host structure. The previously known bismuth telluride iodides, BiTeI and Bi₂TeI, offer physical properties relevant for spintronics. Herewith a new cousin, Bi₃TeI (sp.gr. R3m, a = 440.12(2) pm, c = 3223.1(2) pm), joins the ranks and expands this structural family. Bi₃TeI = [Bi₂][BiTeI] represents a stack with strictly alternating building blocks. Conditions for reproducible synthesis and crystal-growth of Bi₂TeI and Bi₃TeI are ascertained, thus yielding platelet-like crystals on the millimeter size scale and enabling direct measurements. The crystal structures of Bi₂TeI and Bi₃TeI are examined by X-ray diffraction and electron microscopy. DFT calculations predict metallic properties of Bi₃TeI and an unconventional surface state residing on various surface terminations. This state emerges as a result of complex hybridization of atomic states due to their strong intermixing. Our study does not support the existence of new stacking variants BiₓTeI with x > 3; instead, it indicates a possible homogeneity range of Bi₃TeI. The series BiTeI–Bi₂TeI–Bi₃TeI illustrates the influence of structural modifications on topological properties.
Low-Cost Transmitarray Antenna Designs in V-Band based on Unit-Cells with 1 Bit Phase Resolution
(2019)
The eating habits of students differ significantly from those recommended by health practitioners. The aim of this study was to find differences related to diet quality and knowledge on nutrition among Polish, German, and Slovakian students as well as to examine which factors differentiate the diet quality of students from these three countries. The study was conducted on a group of 394 university students from Poland, Germany, and Slovakia. The assessment of diet quality and knowledge on food and nutrition was done with the use of the Dietary Habits and Nutrition Beliefs Questionnaire. The diet of German students was characterized by a significantly higher consumption of legume-based foods, vegetables, and fruit compared to Polish students and Slovakian participants (p < 0.001). The diet of the Poles was characterized by a high consumption of cured meat, smoked sausages, hot dogs, white bread and bakery products, butter, fried foods, and energy drinks. The most important factors significantly associated with diet quality involved the country, place of residence, Body Mass Index (BMI), physical activity, and time spent watching TV or using a computer. Polish students were characterized by the highest level of knowledge on food and nutrition (p < 0.001). However, it was not reflected in their diet. The authorities of universities should aim to provide students with access to canteens on campuses which would offer the possibility of consumption of both affordable and healthy meals.
Zusammenfassung. Mit dem Physical Self-Description Questionnaire Short (PSDQ-S) von Marsh, Martin und Jackson (2010) liegt eine auf 40 Items gekürzte validierte Version des Physical Self-Description Questionnaire von Marsh, Richards, Johnson, Roche und Tremayne (1994) vor, die bereits in mehrere Sprachen übersetzt ist. Die vorliegende Studie evaluierte den deutschsprachigen PSDQ-S anhand von 402 Probanden im frühen und späten Erwachsenenalter. Im Ergebnis lassen die Analyse der Reliabilität und Validität sowie der Vergleich mit den Befunden von Marsh et al. (2010), Stiller und Alfermann (2007) sowie weiterer übersetzter und validierter PSDQ-S-Versionen die Verwendung der deutschsprachigen Kurzform empfehlen. Ebenso wie die Originalversion ist sie für männliche und weibliche Personen, sowie für die Altersgruppen des frühen und späten Erwachsenenalters geeignet. Für alle vier Gruppen besteht eine äquivalente Faktorstruktur.
Arthritis is an illness, which is usually frequently due to degenerative or traumatic causes and can in almost all joints of the human body occur. Joints frequently concerned are for example the hip, knee and shoulder joint. Triggering factors are apart from immobilization also overload and micro traumas. Thus it does not surprise that in the individual kinds of sport some joints are affected by arthritis more frequently than others.
The promotion of the public health represents an important task of the popular sport. In order to be able to manage this task fairly, it is compellingly necessary to analyze the factors taking influence on the activity ratio. The frequent occurrence of pain affects the activity ratio negatively. The popular sport sees itself with an increasing
obsolescence of the population and all the same with older sportsman and club members confronted. Therefore individual kinds of sport must, in order to be arranged attractive for older sportsmen it, be examined on their pain and arthritis of promoting elements. These are to be reduced then and be supplemented by jointcareful exercise and training programs, which make a pain reduced sport exercising possible. Since there are senior groups in many associations, these programs are relevant not only for the individual sportsman to be implement but wide range of importance. Here a close co-operation of coaches and physiotherapists is in demand, in order to become fair to the complex requirements on such a training.
A Brandenburgian Judoka, who trains active for over fifty years, suffers for many years under arthritis in the hip joint. By the implementation of some physical therapy relevant training contents and a regular goal agreement, is it possible to merge the sportsman actively, despite hip joint total endoprosthesis, into the training happening.
To be able to make a representative statement on the relevance of the physical therapy support in the club sport, further investigations are necessary.
The concept of health has several possible definitions. One approach offers the (common) definition of health by the WHO, which distinguishes the physical, 2 psychological and social field. In their connection to the concept of salutogenesis by Aaron Antonovsky and the core objectives of the Health Sports by Klaus Bös and Walter Brehm health promotion programs aim the focus movement to improve the
physical health of the human resource. Consequently, the resulting physical core objective focused physical performance factors, such as the mobility, endurance, strength and coordination. In the study presented here were in the first Phase by means of a multidimensional test battery several basic motor skills of more than 500 non-physically active subjects of advanced middle-aged adults in more than 20 locations detected extending oriented. This was possible on one hand the assessment of achievements for each measurement time point and on the other hand their development as a result of a movement-intensive health promotion program.
In addition to the general performance of the working life requires a job-specific performance or the job-specific specialization of general skills. For the assessment of work-related performance is the Functional Assessment Instrument Capacity Evaluation (FCE) is available. With the aid of standard simulations, the FCE follows
the requirements in the work environment as realistically replicate. In the second Phase (from 2014) the job-specific performance of the subjects is investigated by means of the FCE to build on the test results of the existing health care funding needs-based to expand. The increasing mental and physiosche stress in everyday life and at work leads to increased stress on the job-specific performance and health.
Therefore get multidimensional health support programs, such as the program presented here, a growing importance.
Recent studies of the "male depression" deal among other things with the question of whether men classic depression symptoms are compensated or covered by masked stress symptoms. Symptoms, which may not capture a classic diagnosis of depression are, for example an increased alcohol consumption, increased irritability or increased aggressiveness. This question is strengthened by a simultaneous
consideration of the risk of illness and the suicide rate in relation to women.
Furthermore, the unipolar depression with a prevalence of 10,4% in Germany is the leading cause of impairments of life.
Subject of this study was to survey a population sample of 100 healthy physically and mentally male volunteers aged between 15 and 65 Years of age (mean age 29,64 years) in the Dresden area. Most of the respondents were laborers (46,8%), 29,2% were in training, and the remaining subjects were divided into 17,7% students and 6,3% of college graduates. The survey was conducted by means of two
questionnaires in January 2012 the Gotland Scale of Male Depression for detection of depression risk and the SF-12 as a disease cross-measuring instrument of subjective health-related quality of life. Exclusion factors were already diagnosed depression, mental and neurological disorders. The response rate was 96%. The results of the Gotland Scale documented a reduced well-being with a possible risk of
depression of 13,5%. In evaluation of the FS-12, the results were in the range of gender-specific physical health score was 21,9% and the mental summary scale at 24% outside of the normal range. In the comparison of the two questionnaires was a whole are obtained only a weak negative correlation slightly.
This corresponds to a significantly higher risk of depression for men as it occurs clinically in appearance and suggests that an approximately 50% likelihood of underdiagnosis is. Therefore, further activities in the early detection of stress symptoms in the diagnosis of depression and burn-out should be made.
One of the most commonly performed orthopedic and trauma surgical intervention is, beneath the joint arthroscopic intervention and the implantation of hip prostheses, the endoprosthetic knee replacement. The early postoperative rehabilitation takes place usually in the hospital. Due to the enormous reduction of waiting times it has an even more important role. Currently, therefore, the process guidelines on the content and 2 orientation of therapies are optimized on the basis of current research. A starting point is the application of moderate cooling and their coupling with elements of movement therapy. In contrast to the previous application (before and after a movement of intervention), we apply cold refrigerant during the movement. The aim of this pilot study was the clinical testing of a specially developed and based on Peltier technology sensor-based cooling system, including its assessment of efficacy.
This 8 very elderly patients (Age 78±2,8 years; body height 169±3,7 cm, body mass 84,9±9,4 kg, no other diseases) were divided into two groups and subjected to gait therapy. The treatment group also received a moderate cooling application of 17°C, which was permanently on the o perated knee, while walking. With those results there is intended to be a completely positive effective influence of cooling within the applied temperature range. As much drug-free pain relief and improvement of physical-motor performance (thus option of load increase and higher adaptation rate, shorten the rehabilitation time) in lack of contraindications are noted.
For final representative statements, further studies are necessary due to the small sample size. There is tend to both, excellent suitability, such as a clinical need of the constructed cooling system to be discerned.
In the last 20 years it could be occupied at numerous studies and researches that unemployed persons exhibit a significantly worse state of health compared with working persons. From this it can be derived that an increase of the unemployment duration leads to an increase of the illnesses. Due to different illnesses by unemployment, can develop effects on physical, psychological and social level. In order to work against this process and keep health consequences of long-term
unemployment as small as possible (not least for reasons of the reintegration into the job market), the health promotion stands increasingly in the focus.
A goal of the following study was to find out the effects of a strength-perseveranceoriented back training in regard to physical, psychological and social level. 13 longterm unemployed women (age 56.08 ± 3.17 years) were examined and trained 5 weeks. The state of health and the movement behavior was assessed with an anamnesis. The admission of the objective health parameters was carried out by the determination of the anthropometrics values by means of BIA balance, as well as by the determination of the strength impact from belly and back muscles using Total Trunk. The subjective health parameters were seized over a sensibility to pain scale and a questionnaire to the general habitual well-being. On this basis the obtained results, regarding the anthropometric values and the sensibility to pain, there could not be determined significant changes, but emphasized positive tendencies.
Significant changes showed up with some parameters of the general habitual wellbeing (Well-Being-Score, psychological miss-being), as well as with the strength impact, which took the main meaning regarding the training program.
Therefore it can be said that a 5-week strength-perseverance-oriented back training, improve on the one hand to the physical health, accompanies in view to the strength perseverance ability of belly and back muscules and on the other hand the psychological health, by a significant decrease of the psychological miss-being. Due to the open questions resulting from it further investigations are necessary, in order to confirm the force of expression of the results.
Unspecific peroxygenases (UPOs), whose sequences can be found in the genomes of thousands of filamentous fungi, many yeasts and certain fungus-like protists, are fascinating biocatalysts that transfer peroxide-borne oxygen (from H2O2 or R-OOH) with high efficiency to a wide range of organic substrates, including less or unactivated carbons and heteroatoms. A twice-proline-flanked cysteine (PCP motif) typically ligates the heme that forms the heart of the active site of UPOs and enables various types of relevant oxygenation reactions (hydroxylation, epoxidation, subsequent dealkylations, deacylation, or aromatization) together with less specific one-electron oxidations (e.g., phenoxy radical formation). In consequence, the substrate portfolio of a UPO enzyme always combines prototypical monooxygenase and peroxidase activities. Here, we briefly review nearly 20 years of peroxygenase research, considering basic mechanistic, molecular, phylogenetic, and biotechnological aspects.
Do small landforms have large effects? A review on the legacies of pre-industrial charcoal burning
(2022)
Relict charcoal hearths (RCHs) are small, anthropogenic landforms resulting from past charcoal burning and reaching significant land coverage in pre-industrial mining areas. We review three coupled legacies linked by RCH development: (i) a landscape-scale geomorphic effect, (ii) a unique soil fingerprint, and (iii) an evolving novel ecosystem. The history and technique of charcoal production are described to clarify legacy effects. Applying a recently presented morpho-genetic catalogue is useful for classified mapping of RCH findings. The RCH numbers and calculated RCH densities per study region vary greatly and impose uncertainties due to insufficient methods causing over- or underestimations. Areas with high RCH densities between 50 and 500 RCH/km2 seem reasonable. Machine learning-based remote sensing techniques are promising approaches with which to better assess the full scale of charcoal burning legacies. RCH soil properties feature dark charcoal-rich technogenic substrate layers classified as Auh horizons according to the World Reference Base with significantly increased C contents. These Auh horizons can also exhibit specific physical and chemical properties, such as relatively low bulk density, high porosity, high plant available water content, low thermal conductivity and differences in cation exchange capacity or nutrient status. However, relevant studies are rare, and thus, the effects may differ by study region. Regarding vegetation, there seem to be four main effects: changes in forest structure, species composition, recruitment pattern and productivity. The number of studies on this issue is, however, also very limited. Even fewer studies have examined the soil fauna in RCHs; thus, the reported effects cannot be used to draw general conclusions. Notably, RCH research has made considerable progress in the last five years, especially in the Light Detection and Ranging-based mapping of these small landforms and identification of RCH-specific soil properties, but ecological legacies are not well understood; thus, more interdisciplinary and integrative studies are needed.
The question of connections between pain and strength development and the influence of muscular imbalances on the development of pain and strength deficits has been of interest for therapy scientists for decades.
During the examination period from June until December 2014, one-dimensional isometric trunk strength measurements were carried out on healthy, middle-aged probands using the biofeedback device "Pegasus". The aim was to check out the predefined standard values of the company BfMC and generate standard value ranges for muscular imbalances. Furthermore, these examinations were used to capture occurring forces on other levels to assess their impact on one-dimensional measurements.
A standardized warm up was followed by the determination of the maximum trunk strength in flexion, extension, rotation and lateral inclination. Two measurements on 54 probands at the age of 22.8 ± 3.3 years and an average BMI of 28.9 ± 3.2 were conducted. In addition, the deviating forces were determined.
In target-actual value comparison, the probands were about 17.1% above the normal range of their respective age groups, with an average isometric trunk strength development in all six directions of movement of 835Nm. For the male probands it was also found out that they positioned themselves 63.6% above (average?). The female probands in total were also within the normal range, but 200Nm less power was generated and 34% did not reach the normal range.
Looking at the deviating forces, it is noticeable that 549.1 Nm (54%) were also applied in the other anatomic plains.
Here, there were clear differences between the deviating forces in the isometric testing in the sagittal and frontal plain. In the measurement results of the sagittal plain (Ext; Flex), the deviating forces were 45.8Nm (29.9%) on average in the frontal and transverse direction. In the measurement results of lateral inclination and rotation, the deviating forces were 95.3% and 110% in sagittal and transverse direction.
As a result, it can be noted that, despite the absence of pain, postural imbalances and diseases of the spine, more than half of the forces cannot be generated according to the axis. At this, synergistic functions seem to be physiological in this scope, in order to produce maximum plain equitable forces which basically questions one-dimensional measurements. The test results show significant deviations from the normal range, which raises the issue of the relevance of the defined standard values based on the evaluation of isometric force development.
Further studies will have to prove the relevance of three-dimensional maximum force measurements.
Anterior cruciate ligament rupture with subsequent reconstruction (ACLR) is a common and serious injury in Judo. Athletes rarely return to the peak of performance or are limited in their ability to perform their sport. Performance tests for ACLR are still immature and often unspecific. In Judo, the ability to stand on one's feet is an essential prerequisite for many situations. An unstable standing position also promotes knee injuries. In order to check the stability of the single leg stand, a controlled test-re-test design is used in the present study. Two groups are included: A (n=27): Judoka without anamnestically relevant injuries of the lower extremities or the back and B (n=17): Judoka 5.06 ± 1.06 years after ACLR. A one-legged hop test up on a piezoelectric force plate is examined for reliability with respect to the test repetition and validity with regard to the predicted identification of deficits in a side-by-side comparison. In this test, the test person jumps with one leg on the force plate at a defined distance and tries to stand as still as possible, which means that hardly any horizontal force is generated. Both tests are carried out one after the other with both legs and with sufficient break twice each. In group A, there were no significant differences (p>0.05) between the subjectively better leg and the subjectively worse leg, or the leg in the front and rear of the kumi-kata in Judo. In group B, in the first experiment with the ACLR leg, the test persons generate a significantly higher horizontal force in a 95% confidence interval of the bilateral coefficient of CI=[0.16-0.76] compared to the side not affected (p=0.017). In the test repetition, Group B generates with the affected leg significantly less horizontal force surges than in the first attempt. No significant differences in lateral comparison could be measured, although there is a reliability coefficient of r=0.89 for the ACLR leg, but only r=0.35 for the unaffected leg and r=0.53 for group A. It is concluded that the test for asymptomatic judokas cannot be regarded as sufficiently selective due to the low requirement. In group B, in the second experiment, a feed-forward model including pre-activation based on empirical values from the first experiment could explain the improvement, which has led to no significant differences between legs.
An important aim of the manual therapy is to improve the joint mobility and the functionality to reduce pains in the area
of treatment. In the individual manual-therapeutic treatment mobilizing techniques are mainly used in the spinal column.
The target of this study is to demonstrate the change in segmental mobility of the thoracic spine with asymptomatic subjects. For that an anterior mobilization of the Evjenth/Kaltenborn concept was used. 15 subjects were examined concerning segmental limitations. 11 subjects were included in the study. The subjects had no complaints or preexisting diseases in the spinal column. Their limited segments in area of the thoracic spine were mobilized on two days
of treatment with 5 repetitions and a duration of 50 seconds. In the first treatment a steady pressure of 100 N was applied by using a mobilization wedge. In the second the pressure increased to 140 N. The measurement of the mobility was carried out with the MediMouse method. In the functional tests of the lateral and frontal finger-to-ground distance as well as the thoracic respiratory mobility, the results of both treatments confirmed a significant practical
relevance of the manual-therapeutic mobilization treatment of the thoracic spine. Segmental mobility improvements were also seen, but they need further investigation with regard to the sustainability of the measurement results.
An important performance perequisites in men handball are the conditional abilities. Especially the sprinting skills and
the bounce and reactive capacities of the handball players are convenient. Increasingly performance diagnostic is transferred to the supporting physiotherapists so as, in case of motoric malformation, targeted adjustments affecting the training contants can be made from a physiotherapeutic perspective. This study takes up the aspect of performance diagnostic in the range of speed and reactive strength and pusues their comperance of the 1st and 2nd
team of the handball club Elbflorenz Desden (HCE, N=23). Both teams completed a standardized warm up. Based on a light barrier system the speed strength was measured during a 20 meter sprint. The measurement of the reactive strength followed as drop jump, whereby the ground contact time of the players was collected by using the Opto jump next. The outcome showed significantly higher results in speed and reactive strength of the 1st team. Due to the
performance differences of the two teams, players of the 2nd team should not be playing in the 1st team without acomplishing a specific training of speed strength. On the one hand it would lead to a poorer overall performance and on the other hand increase the susceptibility to injury.
Handgripstrength is used as highlighter for muscural capacity. Also it is capable to predict a healthy aging process and the future morbidity. Because of these facts the handgripstrength is used in the capacity-diagnostics for employment. Aim of this study was to examine the deficits of people from the second labour market comparative to people out of the first labour market. To expose these deficits the handgripstrength of 19 people(nmale=14; nfemale=5) out of the second labour market was measured with an handdynamometer and compared to the average of 28000 people from
the first labour market. The results have shown that there is no lack of perfomance in the handgripstrength of people from the second labour market. Conclusively the handgripstrength as an important requirement for work and reference of the muscural capacity, is not the limiting factor for an employment in the first labour market.
Niedrigwasser ist ein integraler Bestandteil des Abflussregimes, der einen zeitlich und regional begrenzten Zustand in einem oberirdischen Gewässer beschreibt, bei dem der Wasserstand oder der Abfluss einen bestimmten Schwellenwert erreicht oder unterschreitet. Die Kenntnis der Niedrigwasserverhältnisse in einem Gewässer hat damit große Bedeutung für seine zielgerichtete wasserwirtschaftliche Nutzung und ökologische Bewertung.
Niedrigwasser ist in erster Linie bedingt durch Niederschlagsmangel, kann sich jedoch auch durch den Rückhalt des Niederschlags in der Schneedecke, in Gletschern oder im gefrorenen Untergrund ergeben. Zudem kann es anthropogen durch diverse Bewirtschaftungsmaßnahmen im Gewässer oder dessen Einzugsgebiet verstärkt oder abgeschwächt werden.
In diesem Merkblatt werden zunächst die wichtigsten Kenngrößen für das Niedrigwasser definiert: Niedrigwasserabfluss bzw. -wasserstand, Unterschreitungsdauer, Abflussdefizit sowie aus der Dauerlinie abgeleitete Quantile. Für die Ermittlung der Unterschreitungsdauer und des Abflussdefizits sind Schwellenwerte erforderlich. Sie sollten in Abhängigkeit von der Zielstellung der Untersuchung festgelegt werden.
Es werden sowohl die natürlichen und anthropogenen Einflussgrößen auf das Niedrigwasser diskutiert, als auch die genannten Kenngrößen und deren Ableitung aus der Ganglinie vorgestellt. Darauf aufbauend entwickeln sich inhaltlich die Kernthemen des Merkblatts: (1) Wahrscheinlichkeitsanalyse von Niedrigwasserabflüssen und (2) Wahrscheinlichkeitsanalyse von Unterschreitungsdauern und Abflussdefiziten. Mit Hilfe eines Verfahrensablaufs und anhand von Beispielen wird dem Leser schrittweise das methodische Vorgehen vermittelt – von der Festlegung der Kenngröße bis hin zur Ermittlung ihrer Quantile und deren Konfidenzgrenzen. Beide Verfahren setzen Stationarität der zugrundeliegenden Serien voraus, sodass im dritten Kernthema des Merkblatts (instationäre Wahrscheinlichkeitsanalyse) diskutiert wird, welche Möglichkeiten bestehen, um mit signifikanten Instationaritäten im Rahmen der Wahrscheinlichkeitsanalyse umzugehen.