Nearwork-induced transient myopia and accommodation function before and after laser-assisted in situ keratomileusis surgery

Aims: To evaluate the real-life effect of photocatalytic surfaces on the air quality at two test-sites in Denmark. Background: Poor air quality is today one of the largest environmental issues, due to the adverse effects on human health associated with high levels of air pollution, including respiratory issues, cardiovascular disease (CVD), and lung cancer. NOx removal by TiO2 based photocatalysis is a tool to improve air quality locally in areas where people are exposed. Methods: Two test sites were constructed in Roskilde and Copenhage airport. In Roskilde, the existing asphalt at two parking lots was treated with TiO2 containing liquid and an in-situ ISO 22197-1 test setup was developed to enable in-situ evaluation of the activity of the asphalt. In CPH airport, photocatalytic concrete tiles were installed at the "kiss and fly" parking lot, and NOx levels were continuously monitored in 0.5 m by CLD at the active site and a comparable reference site before and after installation for a period of 2 years. Results: The Roskilde showed high stability of the photocatalytic coating with the activity being largely unchanged over a period of 2 years. The CPH airport study showed that the average NOx levels were decreased by 12 % comparing the before and after NOx concentrations at the active and reference site. Conclusion: The joined results of the two Danish demonstration projects illustrate a high stability of the photocatalytic coating as well as a high potential for improvements of the real-life air quality in polluted areas.

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Nanocomposites of Polyaniline and Cellulose Nanocrystals Prepared in Lyotropic Chiral Nematic Liquid Crystals

Journal of Materials ◽

10.1155/2013/614507 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 9

Author(s):

Dawei Zhang ◽

Lihong Zhang ◽

Bingzhe Wang ◽

Guangzhe Piao

Keyword(s):

Liquid Crystals ◽

Cellulose Nanocrystals ◽

Nematic Liquid Crystals ◽

Weight Ratio ◽

Asymmetric Reaction ◽

Reaction Field ◽

Electron Microscopies ◽

Chiral Nematic ◽

Before And After

Stable lyotropic chiral nematic liquid crystals (N*-LCs) of cellulose nanocrystals (CNs) were prepared via hydrolysis using sulfuric acid. The lyotropic N*-LCs were used as an asymmetric reaction field to synthesize polyaniline (PANI) onto CNs by in situ polymerization. As a primary step, we examined the mesophase transition of the N*-LCs of CNs suspension before and after in situ polymerization of aniline (ANI) by polarizing optical microscopy. The structure of nanocomposites of PANI/CNs was investigated at a microscopic level using Fourier transform infrared spectroscopy and X-ray diffraction. Influence of the CNs-to-ANI ratio on the morphology of the nanocomposites was also investigated at macroscopic level by scanning electron and transmission electron microscopies. It is found that the weight ratio of CNs to aniline in the suspension significantly influenced the size of the PANI particles and interaction between CNs and PANI. Moreover, electrical properties of the obtained PANI/CNs films were studied using standard four-probe technique. It is expected that the lyotropic N*-LCs of CNs might be available for an asymmetric reaction field to produce novel composites of conjugated materials.

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In-Situ SEM Observations of Moving Interfaces during Recrystallisation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.519-521.1341 ◽

2006 ◽

Vol 519-521 ◽

pp. 1341-1348 ◽

Cited By ~ 6

Author(s):

Sybrand van der Zwaag ◽

E. Anselmino ◽

A. Miroux ◽

David J. Prior

Keyword(s):

Grain Boundaries ◽

Small Groups ◽

Detailed Understanding ◽

Small Areas ◽

Orientation Contrast ◽

Moving Interfaces ◽

Innovative Method ◽

Before And After ◽

In Situ Observations

To obtain further progress and a more detailed understanding of the mechanisms involved in recrystallisation, new and more accurate techniques such as in-situ observations are necessary. This innovative method has been used to monitor the recrystallisation process in a FEGSEM equipped with hot stage. Observations are done in backscatter mode with particular attention to orientation contrast. EBSD maps of the observed areas can be acquired before and after recrystallisation. Details of the movement of the interfaces between the recrystallised region and the parent structure are recorded and analysed. The results show that the grain boundaries observed do not move smoothly but with a jerky motion. The recrystallising front sweeps through small areas, corresponding to single sub-grains or small groups of them, very rapidly and then stops at other sub-grain boundaries for varying time before progressing to the following area.

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In Situ Coherent X-ray Diffraction during Three-Point Bending of a Au Nanowire: Visualization and Quantification

Quantum Beam Science ◽

10.3390/qubs2040024 ◽

2018 ◽

Vol 2 (4) ◽

pp. 24 ◽

Cited By ~ 4

Author(s):

Anton Davydok ◽

Thomas Cornelius ◽

Zhe Ren ◽

Cedric Leclere ◽

Gilbert Chahine ◽

...

Keyword(s):

Three Dimensional ◽

Reciprocal Space ◽

X Ray Diffraction ◽

Complex Deformation ◽

X Ray ◽

Three Point Bending ◽

Atomic Force ◽

Au Nanowire ◽

Before And After

The three-point bending behavior of a single Au nanowire deformed by an atomic force microscope was monitored by coherent X-ray diffraction using a sub-micrometer sized hard X-ray beam. Three-dimensional reciprocal-space maps were recorded before and after deformation by standard rocking curves and were measured by scanning the energy of the incident X-ray beam during deformation at different loading stages. The mechanical behavior of the nanowire was visualized in reciprocal space and a complex deformation mechanism is described. In addition to the expected bending of the nanowire, torsion was detected. Bending and torsion angles were quantified from the high-resolution diffraction data.

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Length dependence of staircase potentiation: interactions with caffeine and dantrolene sodium

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y99-143 ◽

2000 ◽

Vol 78 (4) ◽

pp. 350-357 ◽

Cited By ~ 10

Author(s):

Dilson E Rassier ◽

Brian R MacIntosh

Keyword(s):

Skeletal Muscle ◽

Gastrocnemius Muscle ◽

Repetitive Stimulation ◽

Mammalian Skeletal Muscle ◽

Optimal Length ◽

Dantrolene Sodium ◽

Length Dependence ◽

Before And After ◽

Isometric Twitch

In skeletal muscle, there is a length dependence of staircase potentiation for which the mechanism is unclear. In this study we tested the hypothesis that abolition of this length dependence by caffeine is effected by a mechanism independent of enhanced Ca2+ release. To test this hypothesis we have used caffeine, which abolishes length dependence of potentiation, and dantrolene sodium, which inhibits Ca2+ release. In situ isometric twitch contractions of rat gastrocnemius muscle before and after 20 s of repetitive stimulation at 5 Hz were analyzed at optimal length (Lo), Lo - 10%, and Lo + 10%. Potentiation was observed to be length dependent, with an increase in developed tension (DT) of 78 ± 12, 51 ± 5, and 34 ± 9% (mean ± SEM), at Lo - 10%, Lo, and Lo + 10%, respectively. Caffeine diminished the length dependence of activation and suppressed the length dependence of staircase potentiation, giving increases in DT of 65±13, 53 ± 11, and 45 ± 12% for Lo - 10%, Lo, and Lo + 10%, respectively. Dantrolene administered after caffeine did not reverse this effect. Dantrolene alone depressed the potentiation response, but did not affect the length dependence of staircase potentiation, with increases in DT of 58 ± 17, 26 ± 8, and 18 ± 7%, respectively. This study confirms that there is a length dependence of staircase potentiation in mammalian skeletal muscle which is suppressed by caffeine. Since dantrolene did not alter this suppression of the length dependence of potentiation by caffeine, it is apparently not directly modulated by Ca2+ availability in the myoplasm.

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SP10.1.7 The Important Role of In-Situ Simulation in Preparing Surgeons for the COVID-19 Pandemic

British Journal of Surgery ◽

10.1093/bjs/znab361.180 ◽

2021 ◽

Vol 108 (Supplement_7) ◽

Author(s):

Pierre Montauban ◽

Charannya Balakumar ◽

Jaideep Rait ◽

Prizzi Zarsadias ◽

Sara Iqbal ◽

...

Keyword(s):

High Risk ◽

In Situ Simulation ◽

Level Of Confidence ◽

Effective Training ◽

Before And After ◽

Quasi Experimental ◽

Surgical Teams ◽

Imminent Threat ◽

The Impact

Abstract Background Effective training is vital when facing viral outbreaks such as the SARS Coronavirus 2 (SARS-CoV-2) outbreak of 2019. The objective of this study was to measure the impact of in-situ simulation on the confidence of the surgical teams of two hospitals in assessing and managing acutely unwell surgical patients who are high-risk or confirmed to have COVID-19. Methods This was a quasi-experimental study with a pretest-posttest design. The surgical teams at each hospital participated in multi-disciplinary simulation sessions to explore the assessment and management of a patient requiring emergency surgery who is high risk for COVID-19. The participants were surveyed before and after receiving simulation training to determine their level of confidence on a Visual Analog Scale (VAS) for the premise stated in each of the nine questions in the survey, which represented multiple aspects of the care of these patients. Results 27 participants responded the pre-simulation survey and 24 the one post-simulation. The level of confidence (VAS score) were statistically significantly higher for all nine questions after the simulation. Specific themes were identified for further training and changes in policy. Conclusion In-situ simulation is an effective training method. Its versatility allows it to be set up quickly as rapid-response training in the face of an imminent threat. In this study, it improved the preparedness of two surgical teams for the challenges of the COVID-19 pandemic.

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Application of the MSAP Technique to Evaluate Epigenetic Changes in Plant Conservation

International Journal of Molecular Sciences ◽

10.3390/ijms21207459 ◽

2020 ◽

Vol 21 (20) ◽

pp. 7459

Author(s):

María Elena González-Benito ◽

Miguel Ángel Ibáñez ◽

Michela Pirredda ◽

Sara Mira ◽

Carmen Martín

Keyword(s):

Dna Methylation ◽

In Situ Conservation ◽

Plant Conservation ◽

Ex Situ ◽

Conservation Strategies ◽

Regenerated Plants ◽

Before And After ◽

Methylation Patterns

Epigenetic variation, and particularly DNA methylation, is involved in plasticity and responses to changes in the environment. Conservation biology studies have focused on the measurement of this variation to establish demographic parameters, diversity levels and population structure to design the appropriate conservation strategies. However, in ex situ conservation approaches, the main objective is to guarantee the characteristics of the conserved material (phenotype and epi-genetic). We review the use of the Methylation Sensitive Amplified Polymorphism (MSAP) technique to detect changes in the DNA methylation patterns of plant material conserved by the main ex situ plant conservation methods: seed banks, in vitro slow growth and cryopreservation. Comparison of DNA methylation patterns before and after conservation is a useful tool to check the fidelity of the regenerated plants, and, at the same time, may be related with other genetic variations that might appear during the conservation process (i.e., somaclonal variation). Analyses of MSAP profiles can be useful in the management of ex situ plant conservation but differs in the approach used in the in situ conservation. Likewise, an easy-to-use methodology is necessary for a rapid interpretation of data, in order to be readily implemented by conservation managers.

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Strategies for school buildings refurbishment in Portuguese climate

E3S Web of Conferences ◽

10.1051/e3sconf/202017218007 ◽

2020 ◽

Vol 172 ◽

pp. 18007

Author(s):

Francisca Cavaleiro Barbosa ◽

Vasco Peixoto de Freitas ◽

Manuela Almeida

Keyword(s):

Energy Consumption ◽

Natural Ventilation ◽

Sensitivity Study ◽

School Buildings ◽

Local Climate ◽

Before And After ◽

Insulation Thickness ◽

Free Running ◽

Near Future

Portuguese school buildings are generally characterized by an in-service thermal discomfort, due to the poor envelope thermal properties and the lack of resources for paying energy consumption. Most Portuguese schools are free-running buildings with a natural ventilation strategy. Hundreds of high and basic schools have not been refurbished and still have problems or anomalies and inadequate in-service conditions and need to be rehabilitated in the near future. There will be, therefore, an opportunity to apply the acquired knowledge of comfort, habits, energy consumption and costs that have been studied since the last refurbishments (2008). This work studies the Portuguese Brandão schools model (from the ’70s), including about 100 non-refurbished basic schools. A prototype classroom was prepared in a Brandão school, in Porto. The in situ experimental campaign consisted of temperature, relative humidity, CO2 concentration and energy consumption measurements. The main tasks of this work are: (1) the validation of an advanced hygrothermal model with experimental measurements before and after the prototype refurbishment; (2) development of a sensitivity study in order to choose the best refurbishment and heating strategies for these buildings, regarding their typology, the local climate features and the actual capacity to support the operating costs; (3) assessment of the roof insulation thickness in Brandão schools; (4) quantification of discomfort indicators.

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Expandable polystyrene without any embedded blowing agent

Journal of Cellular Plastics ◽

10.1177/0021955x20944971 ◽

2020 ◽

pp. 0021955X2094497

Author(s):

Habib Haji Avdi ◽

Morteza Nasiri ◽

Mohammad Javad Tehrani ◽

Maryam Alizadeh Aghdam ◽

Farhang Abbasi

Keyword(s):

Suspension Polymerization ◽

Expansion Ratio ◽

Scanning Calorimetry ◽

Blowing Agents ◽

Blowing Agent ◽

Rate Of Polymerization ◽

Polystyrene Matrix ◽

Expandable Polystyrene ◽

Before And After

In this research, in-situ suspension polymerization of styrene in the presence of graphene, without any blowing agent, was investigated. Steam used in the expansion process of graphene-filled expandable polystyrene (GEPS). The dispersed graphene nano-sheets in the polystyrene matrix may absorb water in high temperatures, which evaporates by lowering the pressure and expansion precedes. The effects of graphene type and loading and steam temperature on the expansion ratio evaluated. Scanning electron microscopy (SEM) used to reveal the cross-section morphologies before and after expansion. The effect of graphene on the polymerization kinetics evaluated by differential scanning calorimetry (DSC). The results showed that by increasing the graphene loading, the rate of polymerization decreased, and the expansion ratio increased. The highest expansion ratio of about 4.8 was for particles containing 0.4% of graphene. Therefore, it was shown that by using graphene as a dispersed phase, polystyrene particles expanded without any organic blowing agents. Here, the idea of expandable polymers without any embedded blowing agent is introduced, which eliminates the release of volatile organic compounds and makes the process environmentally friendly.

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Influence of the Acoustic Cover of the Modular Expansion Joint on the Acoustic Climate in the Bridge Structure Surroundings

Materials ◽

10.3390/ma13122842 ◽

2020 ◽

Vol 13 (12) ◽

pp. 2842

Author(s):

Janusz Bohatkiewicz ◽

Michał Jukowski ◽

Maciej Hałucha ◽

Marcin Dębiński

Keyword(s):

Sound Level ◽

Structural Elements ◽

Expansion Joint ◽

Expansion Joints ◽

The Road ◽

Sound Levels ◽

Road Surfaces ◽

Before And After ◽

Bridge Structures

The noise generated at the interface between the wheels of vehicles and the road surface is well recognized in the literature worldwide. Many publications describe the phenomenon of reducing this kind of impact by silent road surfaces. A specific type of this noise is the sound generated by vehicles passing over the expansion joints of bridge structures. Due to the impulsive nature of this sound, it is very onerous for people living in the close vicinity of bridge structures. The passage of vehicles over expansion joints causes the formation of vibrations that are transmitted to the structural elements of bridge structures, which may cause the formation of the material sounds (especially arduous in the case of bridges with steel elements). An attempt to reduce this impact was made by making a prototype acoustic cover of the expansion joint on the selected bridge. The paper presents the results of research on the “in situ” acoustic effectiveness of this cover. Additionally, the noise was modelled in the object surroundings before and after the cover’s application. The acoustic efficiency of the cover in the whole measured frequency range was 5.3 dBA. In the narrower frequency bands (1/3 octave bands), larger sound level reductions were observed. The maximum sound levels measured under the tested dilatation were less than 10.0 dBA lower than the maximum sound levels measured under the reference dilatation.

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