981 research outputs found
Coworking Spaces and Urban Quality of Life in Istanbul
Co-working spaces can be defined as offices that give the opportunity to carry out individual work in a shared office environment for users from different sectors and disciplines. Co-working spaces provide flexible and alternative working conditions, supported by technical and spatial infrastructures of a working environment. With its spatial characteristics and amenities, co-working spaces promise the users efficient working hours. As well as individual efficiency, co-working spaces are also characterised by their contribution to stimulating social relations and establishing social networks. Worldwide, co-working spaces are expanding through branches, and have the tendency to specialise through the services they offer. Co-working spaces also tend to create a worldwide network through online networks and databases, which contribute to their promotion and communication processes. Today, co-working spaces are a global trend, but they also become specific with their own local dynamics, and gain importance as a contributing factor to the performances of cities in creative sectors within a global network of cities. In this study, the co-working spaces in Istanbul are analysed in terms of services they offer and their spatial characteristics. The aim of the paper is to put forward a description of the character of the co-working space network in the city and its contribution to urban life. This description indicates the role of co-working spaces in improving urban quality of life, in terms of accessibility of alternative working environments and the supportive facilities they offer. In this context, co-working spaces in Istanbul are analysed using their official websites. The results indicate that co-working spaces are particularly prominent in providing social interaction and flexibility characteristics, which are defined as the main components of the services they offer and the identity created for each enterprise. The spatial organisation and design characteristics of the co-working spaces are other prominent factors emphasised when explaining the services of these co-working spaces
Adaptive Expertise and Contextualized Activities in Computer Aided Design
In today’s highly competitive market with economic, environmental, and social challenges, it is imperative that engineers are educated to adapt to the new challenges. Engineering education could play a critical role to improve engineering students’ self-regulated and adaptive skills that are important for their future engineering productivity and innovation. To survive and thrive in the fast-changing workplace, today’s students will need to become adaptive experts. However, current engineering education practices tend to focus too much on the low-level skills required to do specific and routine tasks rather than fostering self-regulated and adaptive skills required for innovation.
Experts are defined in two distinctive characteristics: adaptive experts versus routine experts. Adaptive experts acquire the content knowledge parallel to routine experts in the field; in addition, they have the ability to effectively and innovatively utilize and extend that knowledge. In this dissertation, to determine the “baseline” adaptive expertise among the sample population, an adaptive expertise survey (AES) instrument is administered to both the practicing engineers and the students. The instrument contains questions defining four dimensions of adaptive expertise: multiple perspectives, metacognitive self-assessment, goals and beliefs, and epistemology. Participants’ demographics and engineering experience were recorded and cross-tabulated with their adaptive expertise characteristics captured in the study. In addition this study explored engineering students’ and practicing engineers’ adaptive expertise (AE) characteristics as they used a CAD tool. The practicing engineers were asked to model a component in a CAD program that they were not familiar with. The students were asked to model a stylized familiar component that they brought from home.
In both cases, pre and post interviews were conducted to explore how the participants approached their tasks and overcame any challenges. Effects of the contextualized activity on students’ AE characteristics were investigated. In general, results indicated that as students gain more experience through years their overall AE characteristics were developed. In addition, the studies signified that multiple perspectives, goals and beliefs, and metacognitive skills are good indicators of developing AE and educators should consider promoting those skills in engineering education
Adipobiology of obstructive sleep Apnea syndrome
Obstructive sleep apnea (OSA) syndrome has emerged as a major public health problem because of its high prevalence amongst middle-aged, obese men as well as in lean individuals and women. It has been suggested that obesity`s role in the genesis of sleep apnea is rather through its metabolic activity than a purely anatomic / mechanical impact. Recent studies demonstrate that circulating levels of adipocytes, adipose tissue-derived secretory proteins, are altered in patients with OSA syndrome. For in- stance, leptin level is increased, whereas that of adiponectin decreased in OSA, and these changes can be reversed by treatment of apnea/hypopnea episodes. Adipokine profile seems to change towards a pro inflammatory pattern that may also contribute to OSA-related cardio metabolic diseases. The mechanisms of adipose dysfunction in OSA includes hypoxia, oxidative stress and increased sympathetic nervous activity, including alterations in the circulating levels of the neurotrophins nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF). In effect, reversing hypoxia and attenuating oxidative stress and inflammation through adipokine and NGF/BDNF- targeted pharmacology may provide novel therapeutic opportunities in patients with OSA syndrome
Nanofiber-enhanced lightweight composite textiles for acoustic applications
This paper proposes lightweight textile acoustic structure, wherein electrospun polyacrylonitrile-based nanofibers enhance sound absorption properties with no weight and thickness penalty. Polyacrylonitrile nanofibers with diameter of 110 ± 7 nm were electrospun on spacer-knitted fabrics by varying deposition amount and surface coating arrangement. Proposed novel approach eliminated additional processing steps such as handling and post-lamination and provided easy scalability of nanofibers at macro-scale. The results showed that the sound absorption of nano-enhanced specimens was improved drastically when deposited amount of nanofibers or its effective surface area increased. Sound propagation paths in different configurations were interpreted from sound absorption and air permeability measurements. The sound absorption coefficient values up to 0.7 are achieved in the low and medium frequency ranges with no weight and thickness penalty by tuning deposition amount and surface coating arrangement
Prevalence of Styloid Process Elongation on Panoramic Radiography in the Turkey Population from Cappadocia Region
Circulating irisin levels in newly diagnosed obstructive sleep apnea patients
Introduction: Obstructive sleep apnea syndrome (OSAS) is commonly associated with obesity, insulin resistance, metabolic syndrome, hypertension, and coronary artery disease. Irisin is a newly identified myokine and its serum concentration was found to be correlated with cardiac troponin and creatin kinase-MB in acute myocardial infarction patients. Furthermore, irisin levels were positively associated with endothelium-dependent vasodilation in type 2 diabetic patients.Aim: In this study, we aimed to investigate serum irisin level in the newly diagnosed OSAS patients.Materials and Methods: After obtaining ethical approval, 32 OSAS patients were included. All patients gave written informed consent. Diagnosis of OSAS was verified by an overnight polysomnography (PSG) and made by an apnea hypopnea index equal to or higher than 5. Venous blood samples were collected in the morning between 08.00 – 10.00 after PSG (n=25) or after one-night CPAP treatment (n=7). Serum irisin concentrations were studied by ELISA.Results and Conclusion: Serum irisin concentrations were significantly higher in newly diagnosed OSAS group than in OSAS group after one night of CPAP treatment (199.7±42.4 vs 159.7±18.3 ng/mL respectively; p<0.01). These results suggest that increased serum irisin levels can be reduced by CPAP treatment and elevated serum irisin levels may be due to increased respiratory muscle activity and body temperature.
Assessment of shear bond strength and microleakage of fissure sealant following enamel deproteinization : an in vitro study
To evaluate the effect of two different deproteinizing agents (5.25% sodium hypochlorite and Papacarie®) prior to acid etching on the shear bond strength and microleakage of a fissure sealant material. A total of 123 extracted noncarious human third molar teeth were randomly divided into three groups for each test: acid etching alone (control) (C), sodium hypochlorite (NaOCl), and Papacarie Duo® (PC). The shear bond strength tests were performed using a universal testing machine, and microleakage was evaluated using a dye penetration method. The mean shear bond strength values obtained in Group C were significantly lower than those of Group NaOCl and Group PC (p=0.0001). There were no significant differences between Group NaOCl and Group PC (p>0.05). No statistically significant difference was observed among the groups in terms of microleakage (p>0.05). Papacarie Duo® and 5.25% sodium hypochlorite treatments before etching increased the shear bond strength of the fissure sealant. However, pre-treatment with these agents did not decrease the microleakage between teeth and sealant
Influence of articular arthroscopy-like washout on fracture healing of intra-articular fractures; animal experiment
Aim: To examine whether the application of intra-articular lavage during arthroscopic joint fracture surgery can disturb fracture union and cartilage healing.
Metods: Twenty New Zealand rabbits were then randomly divided into 3 groups; these groups consisted of 2 surgical groups including eight rabbits and a control group consisting of 4 rabbits. After both rear limbs exposed with a medial parapatellar incision, medial femoral condyle was fractured. Four groups were created by doing anatomic reduction or non-anatomic reduction and making irrigation or no irrigation. (Group 1: Fixed by creating a gap and no Irrigation; Group 2: Fixed by creating a gap and irrigation; Group 3: Fixed with complete reduction and no irrigation; Group 4: Fixed with complete reduction and irrigation) X-rays of both knees of all rabbits were taken at the end of the second week and at the end of the eighth week. The operated knees were collected for histopathological analysis.
Results: Radiological data show a significant difference in the level of ossification between the groups in the 2nd week; however, this difference was lost in the 8th week. Histopathologically, at the end of week 8, it was observed that the subchondral bone tissue was incompletely renewed in all the groups. The cartilage tissue of the joint surface was not fully formed and renewed and that it did not completely coalesce with the old cartilage tissue in all of the groups. Compared with the other groups, the group that fracture was anatomically reducted with no irrigation (Group 1), the cartilaginous tissue layer formed was thicker while the surface of the tissue was flatter.
Conclusion: There were no adverse effects of intra-articular lavage on fracture union and cartilage healing in an in vivo environment. Nonetheless, the findings of this study should be confirmed with a larger sample size
Relationship Between Ostiomeatal Complex Variations and Maxillary Sinus Pathologies in Children and Adolescents Using CBCT
Objective: The aim of this study is to evaluate relationship between ostiomeatal complex variations (OMC) and maxillary sinus pathologies in children and adolescents using cone-beam computed tomography (CBCT).
Methods: CBCT images of 72 patients (44 males and 28 females) aged 7-18 years were evaluated retrospectively. Presence of nasal septal deviation (NSD), nasal septal pneumatization (NSP), concha bullosa (CB), accessory maxillary ostium (AMO), agger nasi cell (ANC), Haller cell (HC), Onodi cell (OC), ethmoid sinusitis and maxillary sinus pathologies were investigated. Maxillary sinus pathologies were classified. Correlations of OMC variations with each other, maxillary sinus pathologies and ethmoid sinusitis were investigated. Chi-square test was used to analyze relationships among variables and distribution of parameters.
Results: NSD was determined in 70.8%, NSP in 40.3%, ethmoid sinusitis in 75%, maxillary sinus pathology in 34.8% of images. OMC variations rates were detected as CB 31.3%, AMO 16%, ANC 16%, HC 24.3% and OC 18.8%. The most common maxillary sinus pathology was localized mucosal thickening, with a rate of 15.3% on right and 22.2% on left. Statistically significant differences were determined between almost all OMC variations with each other, and between anatomical variations in OMC with maxillary sinus pathologies except for NSP and AMO (p \u3c 0.05). The presence of ethmoid sinusitis was more common in males (p =0.026).
Conclusion: Anatomical variations in OMC had no significant effect on maxillary sinus pathology except for NSP and AMO. Besides, most of anatomical variations in OMC were statistically significantly correlated with each other. CBCT visualization of these variations is important for sinonasal surgery and is an effective method in children and adolescents with low radiation dose and high image quality compared to computed tomography
The relationship of serum asymmetric dimethylarginine concentrations and lung involvement in patients with COVID-19 infection
Aim: COVID-19 infections the tissue through angiotensin converting enzyme 2 receptor, which is also expressed on endothelial cells. Endothelial dysfunction may be associated with lung involvement. Asymmetric dimethylarginine (ADMA) is an indirect marker of endothelial dysfunction. The aim of our study was to evaluate ADMA concentrations and to identify its association with lung involvement in patients with COVID-19 disease.
Methods: We included 42 patients with COVID-19 infection and lung involvement (Group 1). Forty-two age and sex matched patients without pneumonia acted as the control group (Group 2). All patients gave blood samples for ADMA at the 1st month control visit after discharge. We compared C-reactive protein (CRP) and ADMA concentrations in addition to routine biochemical parameters between groups.
Results: Patients with lung involvement had higher admission glucose, CRP, and ADMA concentrations, and displayed lower hemoglobin concentration and lymphocyte count compared to patients without lung involvement. Although patients with lung involvement had higher ADMA concentrations with respect to those without; plasma ADMA levels were also higher than normal values in control group. Multivariate analysis identified log CRP concentration (OR= 3.047, 95% CI=1.881-5.023, p<0.001) as the independent predictor for lung involvement. And, there was a correlation between ADMA and CRP (r: 0.318, p: 0.003).
Conclusion: We revealed elevated ADMA concentrations as the surrogate of endothelial dysfunction in COVID-19 patients whether they have pneumonia or not
- …