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1.
For biological imaging using electron microscopy (EM), the use of room-temperature ionic liquids (RTILs) has been proposed as an alternative to traditional lengthy preparation methods. With their low vapor pressures and conductivity, RTILs can be applied onto hard-to-image soft and/or wet samples without dehydration – allowing for a more representative, hydrated state of material and opening the possibility for visualization of in situ physiological processes using conventional EM systems. However, RTILs have yet to be utilized to their full potential by microscopists and microbiologists alike. To this end, this review aims to provide a comprehensive summary of biological applications of RTILs for EM to bridge the RTIL, in situ microscopy, and biological communities. We outline future research avenues for the use of RTILs for the EM observation of biological samples, notably i) RTIL selection and optimization, ii) applications for live cell processes and iii) electron beam and ionic liquid interaction studies.  相似文献   
2.
Research on elderly people's ICT acceptance and use often relies on the technology acceptance model (TAM) framework, but has been mostly limited to task-oriented uses. This article expands approaches in technology acceptance and use by developing a model to explain entertainment-related uses of new media technology by elderly people. On a theoretical level, we expand the TAM perspective by adding concepts that act as barriers and/or facilitators of technology acceptance, namely technophobia, self-efficacy and previous experience and expertise with technology. We develop an expanded TAM by testing the role of these concepts in two studies on entertainment media technology. In Study 1, we investigate behavioural intention to use 3D cinema among N?=?125 German elderly media users (Age 50+). In Study 2, we focus the actual use of a computer game simulation by N?=?115 German and US elderly media users (Age 50+). Findings in both studies point towards the central role of perceived usefulness, here modelled as enjoyment, as the reason for elderly people's use and acceptance of entertainment media technology. Perceived ease of use is seen as a precondition for enjoyment, particularly for interactive media.  相似文献   
3.
In this study, we investigated whether wild-thyme (Thymus serpyllum) hydrosol had a preserving effect against spoilage of freshwater fish. Sensorial characteristics, chemical freshness indicator contents, and microbial counts (total aerobes, psychrotrophics, Enterobacteriaceae, fecal coliform bacteria, Aeromonas spp., and Pseudomonas spp.) of whole ungutted and gutted Transcaucasian barb (Capoeta capoeta capoeta Guldenstaedt, 1772) stored on ice produced from wild-thyme hydrosol and tap water at 4 degrees C for 20 days were compared. The results did not reveal any significant (P > 0.05) differences in the microbial counts, sensorial characteristics, pH, and total volatile basic nitrogen values between gutted and ungutted groups. Sensory evaluation and microbiological and chemical analyses indicated that the storage of the fish on ice produced from wild-thyme hydrosol had a significant increase in shelf life by at least 15 to 20 days.  相似文献   
4.
The disturbance attenuation and robust disturbance attenuation problems for Hamiltonian systems in the discrete‐time setting are considered and some new results are presented. The new results are derived utilizing the recently presented dissipativity equality obtained by adding the dissipation rate function to the classical dissipativity inequality. A selection of the dissipation rate function yields new results. These results include a condition on the dissipation structure of the system to achieve the desired disturbance attenuation level and gives direct construction of optimal control laws for any desired disturbance attenuation level. The results remove the need to solve Hamilton–Jacobi–Isaacs inequalities. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
5.
In this work, the monitoring energy and exergy efficiency results of the last heating seasons of operation of the geothermal district heating systems (GDHSs) and their technical availability analysis and monitoring exergoeconomic parameters are presented. The case studies cover the actual system data taken from the systems in Afyon and Salihli GDHSs, Turkey. General energy, exergy, technical availability, and exergoeconomic analysis of the GDHSs are introduced. Furthermore, the average technical availability, real availability, capacity factor and energy and exergy efficiencies value of GDHSs have been analyzed.  相似文献   
6.
Leyla Belkaïd 《Costume》2014,48(1):60-81
This essay describes the evolution of the garment known as a blusa, worn by urban women in north-western Algeria. The blusa, a full-length dress with short sleeves, was conceived and developed in the cities of Tlemcen and Oran. It incorporates locally meaningful traditions as well as fashion styles in conjunction with different cultures. Its transformation illustrates how Algerian women resisted cultural assimilation through dress while creatively appropriating western European textiles, techniques and aesthetics in their clothing, during the French colonial period (1830–1962) and its aftermath. The exploration of the contemporary blusa variations reveals how the relationship between clothing and identity is still highly complex in Algerian cities. To date, the invention, the rituals, the design, and the production of the blusa dress has been little studied. This paper reconstitutes an historical puzzle based on recent object-based research and anthropological investigations. It seeks to interpret the blusa as an interface between tradition and modernity.  相似文献   
7.
In order to prepare a specific melanocortin type 2 receptor (MC2R) ligand, b1-24-corticotrophin was pre-pared in one-step reaction with [18F] SFB and b-1-24-corticotrophin pharmaceutical solution (1 mg/mL, pH=6.5). [18F]SFB was prepared in a semi-automated module in two steps with an overall radiochemical yield of 47% to EOB (not-decay corrected) in 90 min. The 18F-labeled intermediates and 18F-labeled peptide was checked by RTLC and HPLC. The results show that the radiochemical purity is >95% and the yield to EOB (not-decay corrected) is 29% for final 18F-labeled peptide at optimized conditions. Preliminary in vivo studies in normal mice were performed to deter-mine biodistribution of the 18F-labeled peptide for 150 min. The results show that the major tracer uptake is consistent with the natural distribution of MC2R receptors in mammals. Testes/blood and testes/muscle ratios for 18F-labeled peptide at 150 min were 184 and 1.56, respectively, and adipocyte/blood and adipocyte/muscle ratios at 120 min were 221 and 142, respectively. The data support the specific receptor binding of the radiolabeled peptide as reported for MC2R receptor accumulation in adipocytes and testes and demonstrates the retention of biological activity of the pep-tide. This tracer can be used in detection of MC2R distribution in malignancies and sex organ diseases.  相似文献   
8.
In this study, the effects of Pb, Nb, La, and Y replacements were investigated on Bi-based superconducting materials. In preparing the samples, we used a method called solid-state reaction method. The patterns of the X-ray diffraction of all samples indicated presence of Bi-2212 and Bi-2223 phases. The results obtained from XRD revealed that with increase of the melting point of substation elements, the Bi-2223 phase decreased while the Bi-2212 phase and impurity phases of samples grew. From the electrical resistivity measurements using the four-probe method, it was found that sample A with Pb and sample B with La replacements had the maximum and minimum critical temperatures of 111.4 and 81.6 K, respectively. Based on hysteresis loop (M–H) measurement using Bean’s model, estimation of critical current density (Jc) showed that sample A with Pb and sample B with La substitution had the maximum and minimum values respectively. These results may be due to the melting point of these elements with values of 888, 1512, 2315, and 2425 °C for PbO, Nb2O5, La2O3, and Y2O3, respectively. These elements were replaced by Bi2O3 with a melting point of 817 ° C. Further, the samples were prepared at the temperature of 845 °C. It seems at this temperature, these elements not only dissolve within the main matrix and participate in the formation of the Bi-2212 phase during the sintering process but they also participate in the development of the variety of the impurity phases as confirmed by XRD results.  相似文献   
9.
Gallium selenide (GaSe) is a layered compound, which has been exploited in nonlinear optical applications and photodetectors due to its anisotropic structure and pseudodirect optical gap. Theoretical studies predict that its 2D form is a potential photocatalyst for water splitting reactions. Herein, the photoelectrochemical (PEC) characterization of GaSe nanoflakes (single‐/few‐layer flakes), produced via liquid phase exfoliation, for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in both acidic and alkaline media is reported. In 0.5 m H2SO4, the GaSe photoelectrodes display the best PEC performance, corresponding to a ratiometric power‐saved metric for HER (Φsaved,HER) of 0.09% and a ratiometric power‐saved metric for OER (Φsaved,OER) of 0.25%. When used as PEC‐type photodetectors, GaSe photoelectrodes show a responsivity of ≈0.16 A W?1 upon 455 nm illumination at a light intensity of 63.5 µW cm?2 and applied potential of ?0.3 V versus reversible hydrogen electrode (RHE). Stability tests of GaSe photodetectors demonstrated a durable operation over tens of cathodic linear sweep voltammetry scans in 0.5 m H2SO4 for HER. In contrast, degradation of photoelectrodes occurred in both alkaline and anodic operation due to the highly oxidizing environment and O2‐induced (photo)oxidation effects. The results provide new insight into the PEC properties of GaSe nanoflakes for their exploitation in photoelectrocatalysis, PEC‐type photodetectors, and (bio)sensors.  相似文献   
10.
We study a stabilizing multi-model predictive control strategy for controlling nonlinear process at different operating conditions. The control algorithm is a receding horizon scheme with a quasi-infinite horizon objective function that has finite and infinite horizon cost components. The finite horizon cost consists of free input variables that direct the system towards a terminal region which contains the desired operating point. The infinite horizon cost has an upper bound and steers the system to the desired operating point. The system is represented by a sequence of piecewise linear models. Based on the condition of the system states, the sequence of piecewise linear models is updated and the controller’s objective function switches form quasi-infinite to infinite horizon objective function. This results in a hybrid control structure. A recent approach in the analysis of hybrid systems that uses multiple Lyapunov functions is employed in the stability analysis of the closed-loop system. The stabilizing hybrid control strategy is illustrated on two examples and their closed-loop stability properties are studied.  相似文献   
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