1,125 research outputs found
Future extreme precipitation intensities based on a historic event
In a warmer climate, it is expected that precipitation intensities will
increase, and form a considerable risk of high-impact precipitation
extremes. This study applies three methods to transform a historic extreme
precipitation event in the Netherlands to a similar event in a future warmer
climate, thus compiling a future weather scenario. The first method uses
an observation-based non-linear relation between the hourly-observed summer
precipitation and the antecedent dew-point temperature (the PiβTd relation).
The second method simulates the same event by using the convective-permitting
numerical weather model (NWP) model HARMONIE, for both present-day and future warmer conditions. The
third method is similar to the first method, but applies a simple linear
delta transformation to the historic data by using indicators from The Royal
Netherlands Meteorological Institute (KNMI)'14 climate scenarios. A
comparison of the three methods shows comparable intensity changes, ranging
from below the ClausiusβClapeyron (CC) scaling to a 3Β times CC increase per
degree of warming. In the NWP model, the position of the events is somewhat
different; due to small wind and convection changes, the intensity changes
somewhat differ with time, but the total spatial area covered by heavy
precipitation does not change with the temperature increase. The PiβTd method
is simple and time efficient compared to numerical models. The outcome can
be used directly for hydrological and climatological studies and for impact
analysis, such as flood-risk assessments.</p
Sample transformation in online separations:how chemical conversion advances analytical technology
While the advent of modern analytical technology has allowed scientists to determine the complexity of mixtures, it also spurred the demand to understand these sophisticated mixtures better. Chemical transformation can be used to provide insights into properties of complex samples such as degradation pathways or molecular heterogeneity that are otherwise unaccessible. In this article, we explore how sample transformation is exploited across different application fields to empower analytical methods. Transformation mechanisms include molecular-weight reduction, controlled degradation, and derivatization. Both offline and online transformation methods have been explored. The covered studies show that sample transformation facilitates faster reactions (e.g. several hours to minutes), reduces sample complexity, unlocks new sample dimensions (e.g. functional groups), provides correlations between multiple sample dimensions, and improves detectability. The article highlights the state-of-the-art and future prospects, focusing in particular on the characterization of protein and nucleic-acid therapeutics, nanoparticles, synthetic polymers, and small molecules
ΠΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΡΠΉ Π°Π½Π°Π»ΠΈΠ· ΡΠΎΠ½Π΅ΡΠΈΡΠ΅ΡΠΊΠΈΡ ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΠΉ Π² Π°Π½Π³Π»ΠΈΠΉΡΠΊΠΎΠΉ ΡΠ΅ΡΠΈ Π΄Π°ΡΡΠΊΠΎ-Π°Π½Π³Π»ΠΈΠΉΡΠΊΠΈΡ Π±ΠΈΠ»ΠΈΠ½Π³Π²ΠΎΠ²
ΠΠ΄Π½ΠΈΠΌ ΠΈΠ· ΠΊΠ»ΡΡΠ΅Π²ΡΡ
ΠΏΠΎΠΊΠ°Π·Π°ΡΠ΅Π»Π΅ΠΉ, ΠΏΡΠΈΡΡΡΠΈΡ
Π΄Π²ΡΡΠ·ΡΡΠ½ΠΎΠΌΡ ΡΠ΅ΡΠ΅Π²ΠΎΠΌΡ ΠΏΠΎΠ²Π΅Π΄Π΅Π½ΠΈΡ ΠΌΠΎΠ»ΠΎΠ΄ΡΡ
Π΄Π°ΡΡΠ°Π½, ΡΠ²Π»ΡΠ΅ΡΡΡ ΡΠΏΠ΅ΡΠΈΡΠΈΡΠ΅ΡΠΊΠ°Ρ ΠΌΠ°ΡΠΊΠΈΡΠΎΠ²Π°Π½Π½ΠΎΡΡΡ ΠΈΡ
Π°Π½Π³Π»ΠΈΠΉΡΠΊΠΎΠ³ΠΎ ΠΏΡΠΎΠΈΠ·Π½ΠΎΡΠ΅Π½ΠΈΡ, ΡΡΠΎ ΠΎΠ±ΡΠ°ΡΠ°Π΅Ρ Π½Π° ΡΠ΅Π±Ρ Π²Π½ΠΈΠΌΠ°Π½ΠΈΠ΅ ΡΠΆΠ΅ Ρ ΠΏΠ΅ΡΠ²ΡΡ
ΠΌΠΈΠ½ΡΡ ΠΎΠ±ΡΠ΅Π½ΠΈΡ Ρ Π½ΠΈΠΌΠΈ. ΠΡΠ° ΠΌΠ°ΡΠΊΠΈΡΠΎΠ²Π°Π½Π½ΠΎΡΡΡ ΠΏΡΠΎΠΈΠ·Π½ΠΎΡΠ΅Π½ΠΈΡ ΠΏΡΠΎΡΠ²Π»ΡΠ΅ΡΡΡ ΠΊΠ°ΠΊ ΡΠ»Π΅Π΄ΡΡΠ²ΠΈΠ΅ ΡΠΎΠ½ΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΎΠΉ ΠΈΠ½ΡΠ΅ΡΡΠ΅ΡΠ΅Π½ΡΠΈΠΈ, ΠΊΠΎΡΠΎΡΠ°Ρ Π²ΠΎΠ·Π½ΠΈΠΊΠ°Π΅Ρ ΠΏΠΎΠ΄ Π²Π»ΠΈΡΠ½ΠΈΠ΅ΠΌ Π°ΡΡΠΈΠΊΡΠ»ΡΡΠΈΠΈ, ΠΈΠ½ΡΠΎΠ½Π°ΡΠΈΠΈ, ΡΠΈΡΠΌΠΈΠΊΠΈ, ΡΠ΄Π°ΡΠ΅Π½ΠΈΡ ΠΏΠ΅ΡΠ²ΠΎΠ³ΠΎ (Π΄Π°ΡΡΠΊΠΎΠ³ΠΎ) ΡΠ·ΡΠΊΠ° Π½Π° ΡΠΎΠΎΡΠ²Π΅ΡΡΡΠ²ΡΡΡΠΈΠ΅ ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΡ ΠΏΡΠΎΠΈΠ·Π½ΠΎΡΠ΅Π½ΠΈΡ Π²ΡΠΎΡΠΎΠ³ΠΎ (Π°Π½Π³Π»ΠΈΠΉΡΠΊΠΎΠ³ΠΎ) ΡΠ·ΡΠΊΠ°.ΠΠ΄Π½ΠΈΠΌ Π· ΠΊΠ»ΡΡΠΎΠ²ΠΈΡ
ΠΏΠΎΠΊΠ°Π·Π½ΠΈΠΊΡΠ², Π²Π»Π°ΡΡΠΈΠ²ΠΈΡ
Π΄Π²ΠΎΠΌΠΎΠ²Π½ΡΠΉ ΠΌΠΎΠ²Π½ΡΠΉ ΠΏΠΎΠ²Π΅Π΄ΡΠ½ΡΡ ΠΌΠΎΠ»ΠΎΠ΄ΠΈΡ
Π΄Π°Π½ΡΡΠ², Ρ ΡΠΏΠ΅ΡΠΈΡΡΡΠ½Π° ΠΌΠ°ΡΠΊΠΈΡΠΎΠ²Π°Π½ΡΡΡΡ ΡΡ
Π°Π½Π³Π»ΡΠΉΡΡΠΊΠΎΡ Π²ΠΈΠΌΠΎΠ²ΠΈ, ΡΠΎ Π·Π²Π΅ΡΡΠ°Ρ Π½Π° ΡΠ΅Π±Π΅ ΡΠ²Π°Π³Ρ Π²ΠΆΠ΅ Π· ΠΏΠ΅ΡΡΠΈΡ
Ρ
Π²ΠΈΠ»ΠΈΠ½ ΡΠΏΡΠ»ΠΊΡΠ²Π°Π½Π½Ρ Π· Π½ΠΈΠΌΠΈ. Π¦Ρ ΠΌΠ°ΡΠΊΠΈΡΠΎΠ²Π°Π½ΡΡΡΡ Π²ΠΈΠΌΠΎΠ²ΠΈ Π²ΠΈΡΠ²Π»ΡΡΡΡΡΡ ΡΠΊ Π½Π°ΡΠ»ΡΠ΄ΠΎΠΊ ΡΠΎΠ½ΠΎΠ»ΠΎΠ³ΡΡΠ½ΠΎΡ ΡΠ½ΡΠ΅ΡΡΠ΅ΡΠ΅Π½ΡΡΡ, ΡΠΊΠ° Π²ΠΈΠ½ΠΈΠΊΠ°Ρ ΠΏΡΠ΄ Π²ΠΏΠ»ΠΈΠ²ΠΎΠΌ Π°ΡΡΠΈΠΊΡΠ»ΡΡΡΡ, ΡΠ½ΡΠΎΠ½Π°ΡΡΡ, ΡΠΈΡΠΌΡΠΊΠΈ, Π½Π°Π³ΠΎΠ»ΠΎΡΡ ΠΏΠ΅ΡΡΠΎΡ (Π΄Π°Π½ΡΡΠΊΠΎΡ) ΠΌΠΎΠ²ΠΈ Π½Π° Π²ΡΠ΄ΠΏΠΎΠ²ΡΠ΄Π½Ρ ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΠΈ Π²ΠΈΠΌΠΎΠ²ΠΈ Π΄ΡΡΠ³ΠΎΡ (Π°Π½Π³Π»ΡΠΉΡΡΠΊΠΎΡ) ΠΌΠΎΠ²ΠΈ
Π Π΅Π»ΡΠ³ΡΠΉΠ½ΠΈΠΉ ΡΠΈΠ½Π½ΠΈΠΊ Ρ ΠΏΡΠΎΡΠ΅ΡΡ Π²Π΄ΠΎΡΠΊΠΎΠ½Π°Π»Π΅Π½Π½Ρ ΠΠΎΠ½ΡΡΠΈΡΡΡΡΡ Π£ΠΊΡΠ°ΡΠ½ΠΈ
Multiple states of woody cover under similar climate conditions are found in both conceptual models and observations. Due to the limitation of the observed woody cover data set, it is unclear whether the observed bimodality is caused by the presence of multiple stable states or is due to dynamic growth processes of vegetation. In this study, we combine a woody cover data set with an above ground biomass data set to investigate the simultaneous occurrences of savanna and forest states under different precipitation forcing. To interpret the results we use a recently developed vegetation dynamics model (the Balanced Optimality Structure Vegetation Model), in which the effect of fires is included. Our results show that bimodality also exists in above ground biomass and retrieved vegetation structure. In addition, the observed savanna distribution can be understood as derived from a stable state and a slightly drifting (transient) state, the latter having the potential to shift to the forest state. Finally, the results indicate that vegetation structure (horizontal vs. vertical leaf extent) is a crucial component for the existence of bimodality
Does teachers' pedagogical content knowledge affect their fluency instruction?
The relation is studied between teachers' pedagogical content knowledge of reading and the quality of their subsequent classroom behaviour in teaching fluent reading. A confirmatory factor analysis model with two latent variables is tested and shows adequate goodness-of-fit indices. Contrary to our expectations, the results of structural equation modelling reveal a small but significant gamma-value of .29, indicating that only 8% of the variance in teachers' classroom behaviour in teaching fluent reading is accounted for by teachers' pedagogical content knowledge of reading. Presumably teacher knowledge is not as stable and conclusive as one might think. More research is needed in determining the factors that work restricting for teachers in putting their knowledge into classroom practice. It is recommended that preservice and in-service teacher training should not be limited to transfer of knowledge, but should also assist teachers in designing and performing effective fluent reading instruction
Use of in vitro human keratinocyte models to study the effect of cooling on chemotherapy drug-induced cytotoxicity
A highly distressing side-effect of cancer chemotherapy is chemotherapy-induced alopecia (CIA). Scalp cooling remains the only treatment for CIA, yet there is no experimental evidence to support the cytoprotective capacity of cooling. We have established a series of in vitro models for the culture of human keratinocytes under conditions where they adopt a basal, highly-proliferative phenotype thus resembling the rapidly-dividing sub-population of native hair-matrix keratinocytes. Using a panel of chemotherapy drugs routinely used clinically (docetaxel, doxorubicin and the active metabolite of cyclophosphamide 4-OH-CP), we demonstrate that although these drugs are highly-cytotoxic, cooling can markedly reduce or completely inhibit drug cytotoxicity, in agreement with clinical observations. By contrast, we show that cytotoxicity caused by specific combinatorial drug treatments cannot be adequately attenuated by cooling, supporting data showing that such treatments do not always respond well to cooling clinically. Importantly, we provide evidence that the choice of temperature may be critical in determining the efficacy of cooling in rescuing cells from drug-mediated toxicity. Therefore, despite their reductive nature, these in vitro models have provided experimental evidence for the clinically-reported cytoprotective role of cooling and represent useful tools for future studies on the molecular mechanisms of cooling-mediated cytoprotection
Measuring teaching skills in elementary education using the Rasch model
Observation scales for measuring teaching skills were developed for both elementary education and kindergarten. Based on 500 observations, we found that both scales meet the requirements of the dichotomous Rasch model. These observation scales can help in finding the zone of proximal development of teachers in elementary education and kindergarten. This can help in improving teachers' skills
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