18 research outputs found
Hybrid cities and new working spaces – The case of Oslo
No full textRecent decades have seen the emergence of hybrid models of living and working associated typologies. These developments have been analysed from the perspective of different disciplines, each with their own interpretation of this phenomenon. Planning and architecture have addressed hybridization as a specific form of interaction between spatio-functional features (such as mixed use, multi-functionality and flexibility) and social features (such as formal and informal interactions and the spontaneous appropriation of spaces) or have sometimes simply focused on the spatio-functional dimension in urban spaces. Studies from other disciplines (e.g. mobility networks, transportation, sociology and information technology) have shown that hybrid spaces cannot exist without access to digitalization technologies. Such technologies are accelerating hybridization processes. This study examines the complex and layered phenomenon of hybridization as a possible combination of (or interaction between) spatio-functional, social and digital features within the planning debate and related fields. Most of the case studies explored by scholars so far have focused on interactions occurring between residential, social and recreational functions, but working functions are playing an increasingly important role. Furthermore, the COVID-19 pandemic has accelerated the development of new forms of hybridity in cities. As a consequence, the rising use of hybrid (on-site and on-line) working practices, planners, policy makers and stakeholders, as well as scholars, have increasingly discussed the concept of hybridization. In this context, various hybrid typologies of urban spaces have materialized in forms such as new working spaces (NWS) which include co-working spaces, incubators, as well as some cafés and multi-functional public libraries, which have recently provided working spaces. This paper focuses on the evolving concept of hybridity from the planning perspective. Based on five hybrid NWS including their surrounding neighbourhoods in Oslo, it provides empirical evidence for an understanding of the phenomenon that may support the development of hybrid spaces and buildings and develops suggestions for planning strategies. © 2022 The Author
Assessing Zayandeh-Rud Coasts Pollution with Plastic Wastes Based on Clean-Coast Index
No full textPlastic pollution is an important emerging environmental problem with possible impacts on biodiversity and human health. Although the majority of the scholarly attention in this field has been directed to oceans, plastic pollution has not been fully elucidated in freshwater ecosystems. Hence, this study aimed at investigating the spatial distribution and macro- and meso-characteristics of sedimentary plastic waste items along the Zayandeh-Rud River course. 400 types of anthropogenic debris were collected from 21 sampling sites consisting of macroplastic 58.3% (233 items), mesoplastic 18% (72 items), and other waste 23.8% (94 items). Bags (polyethylene), food packs (mainly polypropylene and polystyrene), and bottles (polyethylene terephthalate) were the dominant plastics. The Clean-Coast index was used to determine the river's cleanliness, showing that most parts of the river are clean. The Clean-Coast Index revealed useful implications in evaluating the continuity and success of protective measures such as educational, media, and enforcement actions to reduce river pollution
Occurrence, Abundance and Characteristics of Microplastics in the Sediments of the Zayandeh- Rud River
No full textIntroduction: One of the most important emerging pollutants in aquatic environments that has recently attracted the attention of global researchers in recent years is plastic waste, especially microplastics. Aquatic fauna can ingest microplastics as they confuse it for their prey. Aquatic organisms can easily ingest microplastics because their size is similar to that of the larvae of several organisms, including plankton. Consequently, the animal may develop a sense of satiety after ingesting microplastics, causing reduced food uptake and decreased energy intake, which in turn may affect growth, survival, fecundity and reproduction rate, impacting general fitness of the organisms. Once ingested, these particles can be transferred to higher trophic levels. Despite the fact that freshwater is the only source of drinking water, knowledge about the effects of microplastic pollution in freshwater environments compared to marine environments is still in its infancy. Therefore, the aim of the present study is too comprehensive investigate the presence and distribution of microplastics in the sediments of Zayandeh-Rud River.Materials and Methods: From upstream to downstream of Zayandeh-Rud River, 21 sampling stations were selected and in each station, sampling was done in an area of 30 x 30 cm to a depth of approximately 10 cm above the sediment in three repetitions. Sample processing was done during two stages of organic material digestion using hydrogen peroxide and density separation using sodium chloride salt. Microplastics were identified using a standard light microscope with magnifications of 40x, 100x and 400x. Different standard protocols such as pressure, tension, additional light or hot needle tests were used to detect microplastics. After identifying the microplastic particles, their type and shape, color and size were determined and recorded. Raman spectrometer was used to determine the polymer composition of microplastics.Results: The average abundance of microplastics was 70.481±29.39 particles in 50 gr/dry sediment. Station 17 with an average number of 363.50±14.849 particles and stations 1, 6 and 7 with an average number of 1.33 ±1.528 particles in 50 gr/dry sediment had the highest and lowest levels of pollution, respectively. The size of all microplastics was in the range of 50-5000 micrometers. Microplastics less than 500 microns were the most abundant with 64.5%. The dominant form of microplastics with the frequency of 34.9%, 33% and 28.8% belonged to line, fragment and fiber, respectively. In total, 4 polymers, polypropylene, polyamide, polyurethane and polyethylene, were identified. The results were compared with the reference spectra provided in the Openspecy database. In total, 3 different polymers including polypropylene (PP), polyethylene (PE) and polyamide (PA) were found in sediments.Discussion: The result of this research indicates microplastics dispersion in the sediments of Zayandeh-Rud River. Polypropylene (PP), polyamide (PA) and polyethylene (PE) polymers found in Zayandeh-Rud River sediments are often used in textiles. The composition of the polymer in the sediments clearly indicates the discharge of wastewater from the washing of synthetic textile into the river. Polypropylene and polyethylene are used to make ropes and fishing nets. In addition, polypropylene fibers are widely used for the production of floor coverings, carpets and rugs, sports clothes, making agricultural mulch, fishing nets, packaging bags and ropes. Due to its high strength and hardness, polyamide is used to produce items such as ropes, safety belts, parachutes, thread and fishing nets, as well as in the production of synthetic fibers such as clothes, socks and carpet fibers.Therefore, it can be stated that human activities, including the discharge of urban and industrial wastewater, plastic waste by tourists on the river and also the use of fishing nets by fishermen, play an important role in microplastic pollution in this area. Therefore, developing a program to monitoring microplastics in the water and sediment of Zayandeh-Rud River will be of great help for management measures to control this pollution
Experimental Investigation of Unsaturated Silt-Sand Soil Permeability
No full textThe permeability of unsaturated silt-sand soil is important in many geotechnical and geoenvironmental challenges. Therefore, an appropriate method to evaluate silt-sand soil permeability is important, particularly in Iran where it received little consideration. In this in vitro research, different amounts of fine silt were evaluated on behavior of an unsaturated silt-sand soil with different grain size distribution using a new modified triaxial apparatus. Permeability was measured against matric suction and volumetric water content, and the results are compared against experimental models. The results indicated that the behavior of unsaturated sandy soil permeability could be determined as a function of matric suction, soil void size, and percentage of fine aggregate. Furthermore, the results appeared to imply that an increase of fine contents reduced the permeability, specifically at higher values of suction. This trend for the reduction of soil permeability was related to the increase in the amount of fine contents
Teaching Styles of Teachers in Basic Sciences Classes in Medical School of Isfahan University of Medical Sciences
No full textIntroduction: Teachers’ teaching style is effective on promotion of learning. To achieve this goal, teachers should use different teaching styles. This study has tried to determine teaching styles applied in basic sciences classes in Medical school of Isfahan University of Medical Sciences.
Methods: In a descriptive study in 2008, 74 teachers of basic sciences in medical School of Isfahan University of Medical Sciences were selected through census sampling. The data collecting tool was TSA standard teaching style questionnaire including 61 items. The data were analyzed in form of mean and SD through SPSS.
Results: Based on the findings, %93.2 of teachers used flexible style in domain of teaching methods, %97.3 in classroom management, %71.6 in classroom design and %98.6 in lesson planning skills.
Conclusion: It is recommended that teachers’ teaching styles be selected based on students’ preference. Educational workshops should also be held for teachers to make them familiar with students’ learning styles
Magneto‐/ electro‐responsive polymers toward manufacturing, characterization, and biomedical/ soft robotic applications
No full textMagneto-/ electro-responsive polymers (MERPs) are a class of stimuli-responsive materials that are actuated when triggered by external magnetic/ electric fields. MERPs exhibit rapid, reversible, and safe multi-functional and dynamic (i.e., changing with time) properties, which can effectively be manipulated at different length scales. These features make MERPs very attractive particularly in biomedical engineering (e.g., drug delivery systems and tissue engineering), soft matter engineering (e.g., soft robotics), and structural design of smart materials with unprecedented properties (e.g., complex shape morphing). Due to the recent progress in the design and development of MERPs, here, we highlighted the current advances in fabricating MERPs using various manufacturing methods including 3D/ 4D printing and conventional techniques. We also summarized the methods used for the characterization of MERPs and discussed their important structure-property relationship. We also highlighted the potential applications of MERPs in biomedical engineering, soft robotic, and the design of smart materials and systems. MERPs show great potentials for creating smart materials with predictable dynamic properties. More studies are necessary to investigate the biological responses of MERP both in-vivo and in-vitro, which is essential for biomedical engineering applications.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Biomaterials & Tissue Biomechanic
Numerical Investigation of Water Entry Problem of Pounders with Different Geometric Shapes and Drop Heights for Dynamic Compaction of the Seabed
No full textThe water entry problem of three-dimensional pounders with different geometric shapes of cube, cylinder, sphere, pyramid, and cone was numerically simulated by the commercial software Abaqus, and the effects of pounder shape and drop height from the free surface of water on deepwater displacement and velocity as well as pinch-off time and depth were investigated. An explicit dynamic analysis method was employed to model fluid-structure interactions using a Coupled Eulerian-Lagrangian (CEL) formulation. The simulation results are verified by showing the computed shape of the air cavity, displacement of sphere, pinch-off time, and depth which all agreed with the experimental results. The results reveal that the drag force of water has the highest and lowest effect on cubical and conical pounders, respectively. Increasing the pounder drop height up to the critical height leads to increased pounder velocity while impacting the model bed and more than the critical drop height has a reverse effect on pounder impact velocity. Pinch-off time is a very weak function of pounder impact velocity; but pinch-off depth increases linearly with increased impact velocity.</jats:p
Magnetic Resonance Imaging Features of Diffuse Cavernous Hemangioma of the Uterus Misdiagnosed as a Low Grade Sarcoma: A Case Report
No full textNumerical Investigation of Water Entry Problem of Pounders with Different Geometric Shapes and Drop Heights for Dynamic Compaction of the Seabed
No full textThe water entry problem of three-dimensional pounders with different geometric shapes of cube, cylinder, sphere, pyramid, and cone was numerically simulated by the commercial software Abaqus, and the effects of pounder shape and drop height from the free surface of water on deepwater displacement and velocity as well as pinch-off time and depth were investigated. An explicit dynamic analysis method was employed to model fluid-structure interactions using a Coupled Eulerian-Lagrangian (CEL) formulation. The simulation results are verified by showing the computed shape of the air cavity, displacement of sphere, pinch-off time, and depth which all agreed with the experimental results. The results reveal that the drag force of water has the highest and lowest effect on cubical and conical pounders, respectively. Increasing the pounder drop height up to the critical height leads to increased pounder velocity while impacting the model bed and more than the critical drop height has a reverse effect on pounder impact velocity. Pinch-off time is a very weak function of pounder impact velocity; but pinch-off depth increases linearly with increased impact velocity
Enhanced anticancer potency of hydroxytyrosol and curcumin by PLGA-PAA nano-encapsulation on PANC-1 pancreatic cancer cell line
No full textMany chemotherapeutic regimens have been investigated for advanced unresectable and metastatic pancreatic cancer (PC), but with only minimal improvement in survival and prognosis. Here, we investigated anti-cancer function of free and nano-encapsulated hydroxytyrosol (Hyd) and curcumin (Cur), and its combinations (Hyd-Cur) on PANC-1 cell line. The poly lactide-co-glycolide-co-polyacrylic acid (PLGA-co-PAA) nano-encapsulated Hyd and Cur were synthesized, and MTT assay was performed to evaluate cytotoxic effects of free and nano-encapsulated Hyd, Cur, and Hyd-Cur. Effects of free and nano-encapsulated Hyd, Cur, and Hyd-Cur were evaluated on viability, migration, morphological alterations, colony formation, and apoptosis on PANC-1 cells. We observed that free and nano-encapsulated Hyd, Cur, and Hyd-Cur significantly increased apoptosis rates as well as significantly decreased viability, migration, and colony formation in PANC-1 cells. According to our results, Hyd-Cur combination and nano-encapsulation therapy exerts more profound apoptotic and anti-proliferative effects on PANC-1 cells than free Hyd or Hyd monotherapy
