Measuring the relationship between spatial configuration, diversity and user behavior: A Post Occupancy Evaluation study in Istanbul’s peripheral districts

Post Occupancy Evaluation (POE) is a robust tool to systematically evaluate the effects of design decisions on spatial performance and to identify the relationship between the space and its users. Although there is a growing body of POE research on complex buildings, such as hospitals and education spaces, studies on the POE evaluation of public open spaces are limited. More importantly, few studies have investigated public squares designed at the periphery and how they are used. This study aims to identify the extent to which spatial configuration of public squares is related to users’ behavior (i.e., modes/distances of access, level of satisfaction). For this purpose, we focused on four peripheral urban squares located in Istanbul, Turkey. The methodology applied in the study includes a synthesis of three types of expertise: 1) behavioral mapping of urban squares (through the analysis of patterns of use based on direct observation), 2) cognitive evaluation of spaces based on perceived factors (through user questionnaires), and 3) quantifying urban public spaces objectively (through the methodology of space syntax and urban morphology). The results identify associations between objective characteristics of public spaces designed at the peripheral districts, patterns of use and users’ perception of these areas, to a certain extent. For example, the variety and intensity of activities within the square as well as the length of occupancy are highest for Avcılar square, which is most integrated within its urban surroundings with reduced average block size. An important finding is the association between the average street connectivity levels of these squares with their pedestrian catchment areas. In other words, the more integrated a public urban space is with its surroundings (800mt buffers), its users will access this space on foot from a larger distance. Based on these findings, spatial configuration as measured by space syntax measures appears to be an explanatory measure assessing the potentiality of public open spaces for bringing users together, hence, creating a lively, well-used space. However, the results also point to some disagreements between the perceived (users’ evaluations) and objective (syntactic analysis) measurements, which indicate that both types of measurements are needed in POE research of public spaces.&nbsp

Handedness of orthodontists and its impact on practice

Objective: To assess the handedness prevelance of orthodontists and analyse the discomfort of left-handed orthodontists on practice.Materials and Methods: A questionnaire about the laterality of orthodontists and their discomfort was prepared and distributed to our orthodontic society members. 173 questionnaires were investigated.Results: Fifteen of the participants were left-handed individuals. Of all the 15 samples, only 1 practitioner had been educated with left hand manipulation while studying dentistry. One of the 7 private practioners preferred left-handed chair for his clinic. Regarding left-handed participants working with right-sided chair, 4 of them thought this situation depresses their treatment quality and 9 of them refused. Most of the left-handed participants complaint about the university education.Conclusion: Left-handed orthodontists afford to adapt themselves to a right-handed world. They could to be educated on left-handed dental chairs to display  a more skillful clinical performance

An Atomic Force Microscope with Dual Actuation Capability for Biomolecular Experiments

We report a modular atomic force microscope (AFM) design for biomolecular experiments. The AFM head uses readily available components and incorporates deflection-based optics and a piezotube-based cantilever actuator. Jetted-polymers have been used in the mechanical assembly, which allows rapid manufacturing. In addition, a FeCo-tipped electromagnet provides high-force cantilever actuation with vertical magnetic fields up to 0.55 T. Magnetic field calibration has been performed with a micro-hall sensor, which corresponds well with results from finite element magnetostatics simulations. An integrated force resolution of 1.82 and 2.98 pN, in air and in DI water, respectively was achieved in 1 kHz bandwidth with commercially available cantilevers made of Silicon Nitride. The controller and user interface are implemented on modular hardware to ensure scalability. The AFM can be operated in different modes, such as molecular pulling or force-clamp, by actuating the cantilever with the available actuators. The electromagnetic and piezoelectric actuation capabilities have been demonstrated in unbinding experiments of the biotin-streptavidin complex

Nanomechanics on FGF-2 and Heparin Reveal Slip Bond Characteristics with pH Dependency

Fibroblast growth factor 2 (FGF-2), an important paracrine growth factor, binds electrostatically with low micromolar affinity to heparan sulfates present on extracellular matrix proteins. A single molecular analysis served as a basis to decipher the nanomechanical mechanism of the interaction between FGF-2 and the heparan sulfate surrogate, heparin, with a modular atomic force microscope (AFM) design combining magnetic actuators with force measurements at the low force regime (1 × 101 to 1 × 104 pN/s). Unbinding events between FGF-2–heparin complexes were specific and short-lived. Binding between FGF-2 and heparin had strong slip bond characteristics as demonstrated by a decrease of lifetime with tensile force on the complex. Unbinding forces between FGF-2 and heparin were further detailed at different pH as relevant for (patho-) physiological conditions. An acidic pH environment (5.5) modulated FGF-2–heparin binding as demonstrated by enhanced rupture forces needed to release FGF-2 from the heparin-FGF-2 complex as compared to physiological conditions. This study provides a mechanistic and hypothesis driven model on how molecular forces may impact FGF-2 release and storage during tissue remodeling and repair

The effect of built space on wayfinding in urban environments: a study of the historical peninsula in İstanbul

This paper reconsiders the question of how the built environment, in terms of the spatial configuration of urban layout and land‐use patterns, affects wayfinding performance. In an attempt to develop physical design solutions, first‐time visitors’ directed search patterns within a 2x2km area in the historical peninsula of Sultanahmet, İstanbul, are recorded. The recorded data are analyzed to determine the extent to which street connectivity, measured by metric and directional reach, and visibility patterns, measured by visual integration, visual connectivity and visual clustering coefficient, are related to spatial learning –path selection for exploratory movement. This study enhances previous findings using space syntax by better controlling for the effects of land‐use as compared to the effects of spatial configuration of urban networks. Asserting the independent role of configurational design is important given that urban morphology acts as the long term framework within which land‐uses change over time. The findings imply that the overall spatial configuration of urban layouts –both at the local and global level– may prove to be an important variable for the description and modulation of human spatial behavior in urban environments

Defining a strategical framework for urban pedestrianization projects: assessment of walkability in 3 urban squares in Istanbul

There has been a growing interest in the transformation of major urban squares in Istanbul in recent years. This heightened trend in the urban renewal of prominent areas within the city has led to multiple pedestrianization projects aimed to revitalize urban cores in terms of infrastructure and pedestrian activity. Despite their strategic schemes, these proposed projects lack an objective methodology to implement systematically at various scales. This paper focuses on the walkability of 3 historical urban squares in Istanbul by analyzing their street configuration and land use compositions and comparing it with the levels of pedestrian movement. The main objective of this study is to determine the existing relationship between space allocation and pedestrian activity and to assess the efficiency of proposed pedestrianization projects developed by local authorities for these areas. Overall, the analyses presented in this study emphasize the importance of measures of street connectivity in walkability studies. It is shown that street network configuration; measured using both metric and directional connectivity measures at the road-segment scale is strongly associated with pedestrian movement when controlling for land use compositions at the parcel-level. Based on the spatial analysis and statistical models produced for the research area, a pedestrian-oriented strategical framework that takes into account the existing spatial configuration, parcel-based land-use compositions, as well as pedestrian movement distributions within the areas is proposed for the study areas and their surroundings. With its systematic methodology, efficient spatial models, and strategical approach, this study is anticipated to be used as a unique design framework for prospective urban design and pedestrianization projects for Istanbul

Mandibular anterior bony support and incisor crowding: Is there a relationship?

Introduction: The aim of this study was to test the null hypothesis that increased irregularity of the mandibular incisors is associated with a reduction in the alveolar support on cone-beam computed tomographic sections. Methods: From a sample of 1100 digital volumetric tomographs, 125 tomographs of subjects with Class I malocclusion (mean age, 21.6 +/- 4.8 years) were selected for this study. An irregularity index was used to categorize these tomographs as having mild, moderate, or severe crowding. All tomographs were taken by using an iCAT (Imaging Sciences International, Hatfield, Pa) imaging device. The following parameters were measured on the sections corresponding to the 4 mandibular incisors with the iCAT software: height, thickness, and area of the entire symphysis; height, thickness, and area of the cancellous bone of the symphysis; and distance between the vestibular and lingual cortices. For the statistical evaluation, independent samples t test, analysis of variance, and the Tukey HSD test were used at an alpha level 0.05. The Pearson correlation coefficient and a simple linear regression were calculated to determine the relationship between mandibular anterior bony support and incisor crowding. Results: Almost all mandibular anterior bone measurements were greater in the male subjects than in the female subjects (height of the mandibular symphysis, P<0.001; cancellous bone height, P<0.001). Female subjects with mild crowding had higher values for cancellous bone height (P=0.025) and vestibular cancellous bone thickness (P=0.004) than did those with severe crowding. However, no differences were detected in the male subjects. Additionally, significant correlations were determined between incisor crowding and thickness of the mandibular symphysis, cancellous bone thickness, and the vestibular part of cancellous bone thickness in female subjects. Conclusions: Significant relationships were found between the measures of mandibular incisor crowding and basal bone dimensions in female subjects. Except for the vestibular part of cancellous bone thickness, all mandibular incisor bone measurements were greater in the male subjects than in the female subjects. (Am J Orthod Dentofacial Orthop 2012; 142: 645-53

Cone-beam computed tomography evaluation of relationship between tongue volume and lower incisor irregularity

The aim of this study was to evaluate the relationship between the tongue volume and lower incisor irregularity, using cone-beam computed tomography (CBCT), and to identify the possible gender differences. CBCT images of 60 patients between 16 and 36 years of age were selected from 1400 sets of images in the database. Tomography was carried out using iCAT (R) (Imaging Sciences International, Hatfield, Pennsylvania, USA) and segmentation was carried out by using Mimics 10.1 software (Materialise NV, Leuven, Belgium). The tongue volume was calculated by using the volume of the voxels from the scan and the number of voxels selected for a given mask. Lower incisor crowding was measured with the Little's irregularity index and divided into three groups: mild, moderate, and severe. Independent samples t-test, analysis of variance (ANOVA), and Tukey test were used at P < 0.05 level. Pearson correlation coefficients and linear regression model were calculated to determine the correlation between tongue volume and incisor irregularity. No significant gender dimorphism was found for the tongue volume (females: 28.13 +/- 8.54 cm(3) and males: 31.02 +/- 9.75 cm(3)). According to ANOVA, there was statistically significant difference in the tongue volume measurements among subjects with different levels of irregularity. Tukey analysis indicated that mild irregularity group (33.97 cm(3)) showed higher values for tongue volume than severe irregularity group (26.60 cm(3); P = 0.025). The relationship between incisor irregularity and tongue volume was evaluated for both genders and significant inverse correlation (r = -0.429; P = 0.029) was determined between lower incisor irregularity and tongue volume in males. In female group, no signifi cant correlation was determined between tongue volume and incisor irregularity

Cone-beam computed tomography assessment of mandibular asymmetry in unilateral cleft lip and palate patients

Objective: To determine whether there is any difference between the cleft and non-cleft sides of the mandible in unilateral cleft lip and palate (UCLP) patients, or the right and left sides in control patients; and to determine if there is any difference between the mandibular asymmetry of UCLP patients and that of control patients. Methods: We examined cone-beam computed tomography (CBCT) scans of 15 patients with UCLP and 15 age- and gender-matched control patients. We evaluated 8 linear, 3 surface, and 3 volumetric measurements and compared the cleft/non-cleft sides of UCLP patients and the right/left sides of controls. Results: There were no statistically significant gender differences in any linear, surface, or volumetric measurement. The single significant side-to-side difference in UCLP patients was a longer coronoid unit on the cleft side than on the non-cleft side (p = 0.046). Body volume was significantly lower in the UCLP group than in the control group (p = 0.008). Conclusions: In general, UCLP patients have symmetrical mandibles, although the coronoid unit length is significantly longer on the cleft side than on the non-cleft side. UCLP patients and controls differed only in body volume. (Korean J Orthod 2011;41(6): 431-439

Mandibular asymmetry in unilateral and bilateral posterior crossbite patients using cone-beam computed tomography

Objective: To test the hypotheses that (1) there is no difference in mandibular asymmetry between the crossbite and normal side in a unilateral crossbite group (UCG) and between the right and left sides in a bilateral crossbite group (BCG) and a control group (CG); and (2) there is no significant difference in mandibular asymmetry among crossbite groups and control group