354 research outputs found
Recommended from our members
Process verification of a hydrological model using a temporal parameter sensitivity analysis
Application of two phosphorus models with different complexities in a mesoscale river catchment
The water balance and phosphorus inputs of surface waters of the WeiĂe Elster catchment, Germany, have been quantified using the models GROWA/MEPhos and SWAT. A comparison of the model results shows small differences in the mean long-term total runoff for the entire study area. All relevant pathways of phosphorus transport were considered in MEPhos with phosphorus inputs resulting to about 65% from point sources. SWAT focuses on agricultural areas and estimates a phosphorus input of about 60% through erosion. The mean annual phosphorus input from erosion calculated with SWAT is six times higher than the estimation with MEPhos due to the differing model concepts. This shows the uncertainty contributed by the modelling description of phosphorus pathways
Purification and analytical characterization of an anti- CD4 monoclonal antibody for human therapy
A purification process for the monclonal anti-CD4 antibody MAX.16H5 was developed on an analytical scale using (NH&SO,
precipitation, anion-exchange chromatography on MonoQ or Q-Sepharose, hydrophobic interaction chromatography on phenyl-
Sepharose and gel filtration chromatography on Superdex 200. The purification schedule was scaled up and gram amounts of
MAX.16H5 were produced on corresponding BioPilot columns. Studies of the identity, purity and possible contamination by a
broad range of methods showed that the product was highly purified and free from contaminants such as mouse DNA, viruses,
pyrogens and irritants. Overall, the analytical data confirm that the monoclonal antibody MAX.16H5 prepared by this protocol is
suitable for human therapy
The role of flood wave superposition in the severity of large floods
Abstract. The severity of floods is shaped not only by event- and catchment-specific characteristics but also depends on the river network
configuration. At the confluence of relevant tributaries with the main
river, flood event characteristics may change depending on the magnitude
and temporal match of flood waves. This superposition of flood
waves may potentially increase the flood severity downstream in the main
river. However, this aspect has not been analysed for a large set
of river confluences to date. To fill this gap, the role of flood wave superposition in the flood
severity at downstream gauges is investigated in four large
river basins in Germany and Austria (the Elbe, the Danube, the Rhine and
the Weser). A novel methodological approach to analyse flood wave
superposition is presented and applied to mean daily discharge data from
37 triple points. A triple point consists of three gauges: one in the
tributary as well as one upstream and downstream of the confluence with the
main river respectively. At the triple points, differences and similarities in
flood wave characteristics between the main river and the tributary are
analysed in terms of the temporal match and the magnitudes of flood peaks. At many of the confluences analysed, the tributary peaks consistently arrive
earlier than the main river peaks, although high variability in the
time lag is generally detected. No large differences in temporal matching are
detected for floods of different magnitudes. In the majority of
cases, the largest floods at the downstream gauge do not occur due to
perfect temporal match between the tributary and the main river. In terms of
spatial variability, the impact of flood wave superposition is
site-specific. Characteristic patterns of flood wave superposition are
detected for flood peaks in the Danube River, where peak discharges
largely increase due to inflow from alpine tributaries. Overall, we
conclude that the superposition of flood waves is not the driving
factor behind flood peak severity at the major confluences in Germany; however,
a few confluences show the potential for strong flood magnifications if a temporal shift in flood waves was to occur
What controls the tail behaviour of flood series: rainfall or runoff generation?
Many observed time series of precipitation and streamflow show heavy-tail behaviour. For heavy-tailed distributions, the occurrence of extreme events has a higher probability than for distributions with an exponentially receding tail. If we neglect heavy-tail behaviour we might underestimate the magnitude of rarely observed, high-impact events. Robust estimation of upper-tail behaviour is often hindered by the limited length of observational records. Using long time series and a better understanding of the relevant process controls can help with achieving more robust tail estimations. Here, a simulation-based approach is used to analyse the effect of precipitation and runoff generation characteristics on the upper tail of flood peak distributions. Long, synthetic precipitation time series with different tail behaviour are produced by a stochastic weather generator. These are used to force a conceptual rainfallârunoff model. In addition, catchment characteristics linked to a threshold process in the runoff generation are varied between model runs. We characterize the upper-tail behaviour of the simulated precipitation and discharge time series with the shape parameter of the generalized extreme value (GEV) distribution. Our analysis shows that runoff generation can strongly modulate the tail behaviour of flood peak distributions. In particular, threshold processes in the runoff generation lead to heavier tails. Beyond a certain return period, the influence of catchment processes decreases and the tail of the rainfall distribution asymptotically governs the tail of the flood peak distribution. Beyond which return period this is the case depends on the catchment storage in relation to the mean annual rainfall amount.</p
Pengaruh Karakteristik Pekerjaan, Kompensasi, Dan Kepuasan Kerja Terhadap Produktivitas Kerja Karyawan Pada CV. Ibu Sri âTilungâ Di Boyolali
The purpose of this study is to determine the effect of labor characteristics, compensation, and job satisfaction on employee productivity in CV Ibu Sri Tilung. This study also aims to determine jointly the influence of the three independent variables to the dependent variable. The type of research is quantitative research, with a sample of 35 respondents. Sampling using convinience-purposive sampling technique. Techniques of collecting research data through questionnaires with Likert scale. Data analysis methods used were validity test, reliability test, classical assumption test, and multiple linier regression analysis test. The result showed that both the partial and simultaneous variables influence the characteristics of labor, compensation and job satisfaction have a positive and significant effect on employee work productivity. In the determinant coefficient (R ÂČ), the result is 0.918, it means that the variable of labor characteristics (X1), compensation (X2), and job satisfaction (X3) are able to explain the work productivity (Y) variable of 0.918 or 91.8%, and the rest can be explained variable other outside the research model
How do changes along the risk chain affect flood risk?
Flood risk is impacted by a range of physical and socio-economic processes.
Hence, the quantification of flood risk ideally considers the complete flood
risk chain, from atmospheric processes through catchment and river system
processes to damage mechanisms in the affected areas. Although it is
generally accepted that a multitude of changes along the risk chain can occur
and impact flood risk, there is a lack of knowledge of how and to what extent
changes in influencing factors propagate through the chain and finally affect
flood risk. To fill this gap, we present a comprehensive sensitivity analysis
which considers changes in all risk components, i.e. changes in climate,
catchment, river system, land use, assets, and vulnerability. The application
of this framework to the mesoscale Mulde catchment in Germany shows that
flood risk can vary dramatically as a consequence of plausible change
scenarios. It further reveals that components that have not received much
attention, such as changes in dike systems or in vulnerability, may outweigh
changes in often investigated components, such as climate. Although the
specific results are conditional on the case study area and the selected
assumptions, they emphasize the need for a broader consideration of potential
drivers of change in a comprehensive way. Hence, our approach contributes to
a better understanding of how the different risk components influence the
overall flood risk.</p
Recommended from our members
Conceptualising quality of life for older people with aphasia
Background: There is an increasing need in speech and language therapy for clinicians to provide intervention in the context of the broader life quality issues for people with aphasia. However, there is no descriptive research that is explicitly focused on quality of life (QoL) from the perspectives of older people with aphasia.
Aims: The current study explores how older people with chronic aphasia who are living in the community describe their QoL in terms of what contributes to and detracts from the quality in their current and future lives. The study is descriptive in nature, and the purpose is to conceptualize the factors that influence QoL.
Methods & Procedures: Thirty older participants (16 women, 14 men) with mild to moderate aphasic impairment took part. All participants had adequate communication skills to participate: demonstrating reliable yes/no response and moderate auditory comprehension ability. Participants were interviewed in their own homes using six brief unprompted open questions about QoL, in a structured interview. The first five questions were drawn from previous gerontological research (Farquhar, 1995), and a sixth question specifically targeting communication was added. Content analysis was used, identifying discrete units of data and then coding these into concepts and factors. Additional demographic information was collected, and participantsâ mood on day of interviewing was assessed using the Geriatric Depression Scale (Sheikh & Yesavage, 1986).
Outcomes & Results: Activities, verbal communication, people, and body functioning were the core factors in QoL for these participants, and they described how these factors both contributed quality in life as well as detracted from life quality. Other factors that influenced QoL included stroke, mobility, positive personal outlook, in/dependence, home and health. Whilst the findings are limited by the lack of probing of participantsâ responses, the study does present preliminary evidence for what is important in QoL to older people with aphasia.
Conclusions: Quality of life for older people with predominantly mild to moderate chronic aphasia who are living in the community is multifactorial in nature. Some factors lie within the remit of speech and language therapy, some lie beyond the professional role, but all are relevant for consideration in rehabilitation and community practice. Further qualitative research is implicated to better understand QoL with aphasia, using in-depth interviewing with a broader range of people with aphasia
- âŠ