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Spectral properties and thermal quenching of Mn4+ luminescence in multicomponent garnet hosts
(2018)
Synthesis and Luminescence of the New Ligand Exchanged Cluster Compound (n-Bu4N)2[Mo6I8(CH3SO3)6
(2018)
Bridging the scales in high-throughput dielectrophoretic (bio-)particle separation in porous media
(2018)
Bedload transport and hydro-abrasive erosion at steep bedrock rivers and hydraulic structures
(2018)
Abrasion in a concrete-lined sediment bypass tunnel is estimated using a Japanese state-of-the-art prediction model and validated by measured invert abrasion data at Asahi Reservoir, Japan. The model is described in detail, certain shortcomings are disclosed, and a revised version is proposed. The model consists of a kinetic energy term accounting for the impact by saltating particles, and a friction work term accounting for the grinding stress. It is found that the latter term yields concrete abrasion values being consistently a multiple compared to its kinetic term contradicting other research. Based on that, and a possible particle impact angle inconsistency, it is proposed to omit the friction work term. It is shown that the calculated abrasion is overestimated by 138% on average compared with that measured, if both terms are accounted for. However, promising results are obtained with only 30% overestimation by neglecting the friction work term.
To achieve the sustainable use of dams, the development of methods for sediment management in reservoirs is required. One such method includes the use of Sediment Bypass Tunnels (SBTs) to divert sediment around a dam, thereby preventing sedimentation in the reservoir. However, SBTs are prone to severe invert abrasion caused by the high sediment flux. Therefore, it is necessary to establish a measurement system of the sediment transport rate in these tunnels. One system to measure sediment transport in rivers is the Swiss plate geophone, which can register plate vibrations caused by particle impact. In Japan, the Japanese pipe microphone is used, and sediment transport is measured based on the sound emitted by the particle impact. In this study an attempt was made to optimize the advantages of both systems by fixing a microphone and an acceleration sensor to a steel plate. The results of calibration experiments with this new system are presented and compared with the existing methods. It was found that the acceleration sensor can detect sediment particles larger than 2 mm in diameter. Moreover, a new parameter, referred to as the detection rate, was introduced to describe the correlation between the actual amount of sediment and the registered output. Finally, two parameters - the saturation rate and hit rate - are introduced and exhibit strong correlation with the detection rate.
This paper describes the design of the new tunnel invert lining of the 9-foot tunnel at Mud Mountain Dam, Washington, USA. The tunnel diverts all bed load sediments into the tailwater. Major invert abrasion has been observed in the existing steel lining. The new invert design consists of 0.59 m2 and 0.79 m2 granite blocks that are 0.25 m thick and placed tightly together along the tunnel. Stability analysis showed factors of safety ranging from 1.2 to 2.6 against uplift. This will be achieved with strip drains placed in the bedding material along the tunnel. A service-design-life analysis was performed using abrasion prediction modelling.
This model was based on abrasion measurement data acquired from granite field tests at Pfaffensprung sediment bypass tunnel, Switzerland. The estimated annual abrasion depths for the granite were approximately 0.50 mm/year for average sediment transport conditions.
Without adequate measures, reservoirs are not sustainable, neither the
reservoir itself due to continuous sedimentation, nor the downstream ecosystem due to altered sediment continuity. Appropriate actions are inevitable and require a systematic sedimentation management. Sediment bypassing constitutes one effective strategy that routes sediment load around reservoirs during floods. A sediment bypass system has the advantage that only newly entrained sediment is diverted from the upstream to the downstream reach thereby re-establishing sediment connectivity. Hence, such a system contributes to a sustainable water resources management while taking the downstream environment into consideration. This paper gives a state-of-the-art overview
encompassing design, bypass efficiency, hydraulics, challenges due to abrasion, positive effects on both downstream morphology and ecology, and makes design recommendations.
In this paper typical bypass efficiencies of sediment bypass tunnels (SBTs) used to counter reservoir sedimentation are described, distinguishing between two layouts of the tunnel intake. It results that SBTs are an effective measure to reduce the sedimentation of dam reservoirs, particularly of type (A) with intake at the reservoir head. The hydroabrasive wear of tunnel inverts is significant and
has to be mitigated by using adequate invert liners. The invert abrasion can be estimated based on an abrasion model where a correct input value of the bed material resistance coefficient is paramount to limit model uncertainties. Based on abrasion measurements at prototype SBTs typical values of the material resistance coefficient are recommended for high-strength concrete, natural stones and steel liners. The field experiences gathered so far and the comparison of various invert materials suggest granite pavers as a promising lining material for severe abrasion conditions.
Startups have the potential to transform industries as they follow partly divergent business strategies and have the ability to develop new innovative products. The evolving fields of digitalization, sustainability and urbanization highlight the direction of change. Due to enormous time pressure and lack of knowledge, corporations rely heavily on external sources of knowledge to increase innovativeness. Therein, startups take a special role. Joint R&D projects, investments or strategic buyer-supplier agreements with startups grant corporations access to their innovative technologies. This paper gives insights into the organization of search processes to identify innovative startups and highlights approaches to initiate collaborations. Therefore, a multiple-case study among automotive OEMs and suppliers was conducted. The research ends with organizational structures, an identification process, and various instruments developed for the identification of startup innovations. Furthermore, propositions are made for a successful collaboration between startups and established corporations, displaying the role of purchasing in startup management, the need to take fast decisions, secure technical support by experts within their organization and build strong relationships with partners within their supply chain and new partners, as for example venture capitalists.
The design of anion-sensitive probes with sufficient sensitivity and selectivity is a demanding task in analytical sciences and chemical sensor technology. The reversible binding of anions to lanthanide centers is a possible approach for the development of molecular anion sensors, as reversibility is a prerequisite for continuous sensing and monitoring of enzymatic reactions. Some anion species lead to a strong increase of luminescence intensities and lifetimes by the replacement of luminescence quenching water molecules, though the selectivity of the luminescence response is still a major problem. We synthesized a series of positively charged pyridyl-based multidentate europium complexes (five-, four- and three dentate) including sensitizing chromophores and studied their luminescence intensity and lifetime responses to different polyphosphates, pyrophosphate, phosphate anions, and carboxyanions. The results revealed that the number and symmetry of the binding sites have a significant impact on the response. The five-dentate complex was used for the real-time monitoring of the activity of the ATP hydrolyzing enzyme apyrase.
Due to highly sophisticated, specialised models and data in production, digital twins, as defined as full digital representations, are neither computationally feasible nor useful. The complementary concept of digital shadows will provide cross-domain data access in real time by combining reduced engineering models and production data analytics.
Parents’ attitudes towards inclusive education in day care facilities in the city and rural district of Osnabrueck in Germany were assessed by conducting a written survey (N = 809). In the survey, parents indicated their perceptions of advantages and risks of inclusion for children with and without special needs. The interviewed parents perceived more advantages than risks for both groups of children. The results of the assessment varied depending on the
kind of child care facility. The paper concludes with
recommendations for future research and about how institutions should develop to adequately go about the implementation of inclusive education.
Early Intervention in Gaming Disorder: What Can We Learn from Findings in the Substance Abuse Field?
(2018)
The objective of this paper is to compare food consumption by Cambodian garment workers with and without access to a free model lunch provision through a factory-based canteen. Data from an exploratory randomised controlled trial were analysed. In total, 223 female Cambodian garment workers were allocated to an intervention arm (six-month lunch provision) or a control arm. Dietary intake on workdays was assessed by qualitative 24-h recalls at baseline and twice at follow-ups during the period of lunch provision using the Food and Agricultural Organization (FAO) guideline on assessing women's dietary diversity. In total, 158 participants provided complete data on the dietary intake over workdays at all interviews. Lunch provision resulted in a more frequent consumption of dark green leafy vegetables (DGLV), vitamin A-rich fruits, other fruits, and oils and fats during lunch breaks. In contrast, flesh meats, legumes, nuts and seeds, as well as sweets, were eaten at a lower frequency. Except for a higher consumption rate of vitamin A-rich fruits and a lower intake frequency of sweets, lunch provision had a less clear impact on total 24-h intake from different food groups and was not associated with a higher women's dietary diversity score (WDDS). A more gap-oriented design of the lunch sets taking into account underutilised foods and the nutritional status of the workers is recommended.
This paper focusses on effective teaching and learning methods in the context of a larger project that aims to align objectives in higher education with employer requirements in the field of purchasing and supply management (PSM). The reason is that little is known about which specific skills and competencies of PSM professionals are needed outside academia and which learning objective higher education should incorporate to meet the practical PSM requirements of firms and organisations. Practice as well as literature share the understanding that PSM professionals need a well-balanced mixture of knowledge and soft-skills: the merely explicit know-what (codified knowledge), know-why (theory), know-how (method) and inter- & intrapersonal soft skills.
External sources of knowledge have become a necessary extension to internal innovation activities (Monteiro, Mol and Birkinshaw, 2017; Rosenkopf and Nerkar, 2001). Collaborations with customers, suppliers, universities or even competitors are a promising way to extend the own knowledge base in order to increase the firm´s innovativeness (Felin and Zenger, 2014; Laursen and Salter, 2006). onsidering this potential set of external partners, suppliers seem to have the largest impact on product innovation (Un, Cuervo-Cazurra and Asakawa, 2010). Yet, suppliers’ innovative potential is limited as described in a case study by Gassmann, Zeschky, Wolff, and Stahl (2010), which further shows how a new venture supplier, commonly referred to as “startup”, has succeed at providing a truly innovative idea (a haptic feedback control device for automobiles). Therefore, startups as a specific knowledge provider have received growing attention (Weiblen and Chesbrough, 2015; Zaremba, Bode and Wagner, 2016). By collaborating with startups, corporations hope to benefit from the startups´ entrepreneurial characteristics, such as alertness, creativity, flexibility and willingness to take risks (Audretsch, Segarra and Teruel, 2014; Criscuolo, Nicolaou and Salter, 2012; Marion, Friar and Simpson, 2012).
Approximately 300,000 asylum-seeking children arrived in Europe in 2015. The chance of experiencing a traumatic event is very high for fleeing children. Since the origin of the refugees is widespread, the languages spoken are diverse. Multilingual electronic patient-reported outcome systems (ePROs) can be used to gather medical data in a foreign language and display the results in the health professionals' language, which helps overcoming the language barrier. Utilizing such a system, a two-phase study aiming to screen refugee minors for potential mental health issues has started. Potential eligible participants are examined using questionnaires with good psychometric properties and cross-cultural applicability. To date, 75 minors and 21 of their relatives participated in the study, being German and Arabic the most desired languages for the electronic survey. Developing a system that provides multilingual questionnaires entails several drawbacks like a cumbersome translation process and dealing with writing directions. The proposed translation process and the ePRO can be re-used in similar studies.
Persistent feelings of gender dysphoria (GD) are accompanied by distress and body dissatisfaction in most clinically referred adolescents and adults. Transition-related medical interventions (e.g., puberty suppression, hormones, or surgery) may alleviate body dissatisfaction. The aim of the present cross-sectional study was to compare multidimensional body image across clinically referred adolescents and adults undergoing different transition-related medical interventions. Two clinical samples of adolescents (n = 82) and adults (n = 120) referred to specialized departments of four different transgender health services in Germany participated in the study. In total, 202 individuals from the female-to-male (FtM individuals) and male-to-female (MtF individuals) spectrum aged 14-74 years were included at different stages of their transition. Four scales assessing multidimensional aspects of body image (measured by the Body Image Assessment Questionnaire, FBeK) were compared across three groups: sample, gender, and medical interventions (while controlling for age and treatment duration). The results indicated less favorable body image scores compared with the norm in both adolescents and adults with GD. Individuals who had undergone transition-related medical interventions presented a significantly better body image on two of the four scales. Differences according to gender and age were also present. These findings suggest that medical interventions, especially gender-affirming hormones and surgery, are generally beneficial to the body image in individuals with GD. However, not all of the less favorable outcomes in multidimensional body image were positively influenced by the treatment conditions and may thus benefit from additional integrative counseling before and during transition.
Despite growing interest in light-driven ion pumps for use in optogenetics, current estimates of their transport rates span two orders of magnitude due to challenges in measuring slow transport processes and determining protein concentration and/or orientation in membranes in vitro. In this study, we report, to our knowledge, the first direct quantitative measurement of light-driven Cl− transport rates of the anion pump halorohodopsin from Natronomonas pharaonis (NpHR). We used light-interfaced voltage clamp measurements on NpHR-expressing oocytes to obtain a transport rate of 219 (± 98) Cl−/protein/s for a photon flux of 630 photons/protein/s. The measurement is consistent with the literature-reported quantum efficiency of ∼30% for NpHR, i.e., 0.3 isomerizations per photon absorbed. To reconcile our measurements with an earlier-reported 20 ms rate-limiting step, or 35 turnovers/protein/s, we conducted, to our knowledge, novel consecutive single-turnover flash experiments that demonstrate that under continuous illumination, NpHR bypasses this step in the photocycle.
Evaluation competencies in the context of diversity training: The practitioners’ point of view
(2018)
Towards an Omni-Channel Framework for SME Sales and Service in the B2B Telecommunications Industry
(2018)
Beyond managing research partnerships: Partnered research as an integrated methodological approach
(2018)
Stormwater quality models are usually calibrated using observed pollutographs. As current models still rely on simplified model concepts for pollutant accumulation and wash-off, calibration results for continuous pollutant concentrations are highly uncertain. In this paper, we introduce an innovative calibration approach based on total suspended solids (TSS) event load distribution. The approach is applied on stormwater quality models for a flat roof and a parking lot for which reliable distributions are available. Exponential functions are employed for both TSS buildup and wash-off. Model parameters are calibrated by means of an evolutionary algorithm to minimize the distance between a parameterized lognormal distribution function and the cumulated distribution of simulated TSS event loads. Since TSS event load characteristics are probabilistically considered, the approach especially respects the stochasticity of TSS buildup and wash-off and, therefore, improves conventional stormwater quality calibration concepts. The results show that both experimental models were calibrated with high goodness-of-fit (Kolmogorov–Smirnov test statistic: 0.05). However, it is shown that events with high TSS event loads (>0.8 percentile) are generally underestimated. While this leads to a relative deviation of −28% of total TSS loads for the parking lot, the error is compensated for the flat roof (+5%). Calibrated model parameters generally tend to generate wash-off proportional to runoff, which is indicated by mass-volume curves. The approach itself is, in general, applicable and creates a new opportunity to calibrate stormwater quality models especially when calibration data is limited.
Results from a long-term stormwater quality monitoring program were used to derive total suspended solids (TSS) event load distributions at four small urban environments (flat roof, parking lot, residential catchment, high traffic street). Theoretical distribution functions were fitted to the empirical distribution functions obtained. Parameters of the theoretical distribution functions were optimized with respect to a likelihood function to get both optimized parameters and standard errors. Kolmogorov-Smirnov and Anderson-Darling test statistics were applied to assess the goodness-of-fit between empirical and theoretical distribution. The lognormal distribution function was found to be most expressive to approximate empirical TSS event load distributions at all sites. However, the goodness-of-fit of the statistical model strongly depends on the number of events available. Based on the results of a Monte-Carlo-based resampling strategy, around 40 events should be considered.