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Determination of the type of precipitated calcium sulfate in mixing two incompatible injection and formation waters was studied experimentally in this work at two temperatures of 26oC and 80oC. Here the SEM, EDX and XRD techniques have been used to inspect the temperature effects on the morphology, type, and size of the precipitated calcium sulfate crystals. The results of this work show that the precipitated scales at these temperatures are calcium sulfate dihydrate and the temperature influences the size of crystals dramatically. The crystallization mechanism is the next issue which has been studied in this work. Measuring the amount of precipitated scale in the mixing of the incompatible waters versus time depicts the scale formation controlling mechanisms. According to the obtained results in this work, three primary nucleations, crystal growth, and secondary nucleation control the calcium sulfate scale precipitation.

Water injection into near dew point gas condensate reservoirs is a common method to delay the condensate dropout near the wellbore. Also water can be injected as waste water disposal into the depleted gas reservoirs or to increase the oil recovery in primary enhanced oil recovery process. All of these processes result in mixing of incompatible injection and formation waters which finally causes mineral scale formation. Gypsum is one of the most common mineral scales which is precipitated uring the mixing of incompatible waters in porous media. This scale can reduce the reservoir rock permeability which affects the success of continuous water injection in hydrocarbon reservoirs. The mineral scale formation through the porous media can be determined if the suitable dispersion coefficient is estimated. Dispersion coefficient is already estimated by neglecting the effects of porous media or using unsuitable tracers which might affect the rate of scale precipitation. Two main issues have been investigated in this work. The first one is the development of an experimental method to measure the dispersion coefficient by a proper tracer which has no interaction with the other ions in porous media. The second one is modeling the concentrations of ions in porous media by two approaches. In this study the standard diffusivity equation and the capacitance approach are used to model the concentration profiles for all ions. The results of this work suggest the application of the capacitance model for the heterogeneous rocks and the standard diffusivity model for the homogeneous ones.

Street trading has become integral to how public space works in cities of the global South. It cannot be considered as marginal since it gears to the urban economy and works as a key mode of income generation for the urban poor to sustain livelihoods. A poor understanding of how forms of street trading work in public space can lead to poor design and policy interventions. While many practices of formalization aim at the elimination of informality, the challenge is to explore the complex informal/formal relations and the dynamics of street trading to understand how forms of informality negotiate space and visibility in the public realm. In this paper, we propose a typology of street trading, based on the criteria of mobility within public space and proximity to public/private urban interfaces. While exploring the degrees of mobility in informal street trading can be crucial to the modes of governance and adaptability involved, of critical importance is to investigate how street trading takes place in relation to the built form&mdash, particularly the edges of public space where public/private interfaces enable or constrain exchange and appropriation. The developed typology provides a better understanding of the dynamics of street trading and contributes to the ways in which the built environment professions can most effectively engage with interventions in public space without eradicating the scope for informal adaptations.

Water injection to reservoirs for recovery increase is a common enhanced oil recovery method in petroleum industry. Water injection might give a negative result due to scale formation and inducing damage in porous media. The compatibility study of mixed waters should be done before deciding about the water injection in reservoir. The time required for the mixture of incompatible waters to reach the maximum potential of scale at desired condition of temperature and pressure is not fully discussed in literature but it is very crucial and is highly dependent to crystallization process. This work may be proved to be of great value in understanding the crystallization process of calcium sulfate due to mixing of formation and injection waters by experimental approach. To simulate the effect of fluid velocity in porous media on the amount of precipitated scale, the experiments are done at two condition of not agitated as well as agitated one. Three zones at which primary nucleation, crystal growth or secondary nucleation controls the scale precipitation has been determined by measuring the amount of scale at different times. The results show that agitation and increasing temperature altogether have an important role on crystallization and reduction of the reaction time required to get the final potential of produced scale. The changes in crystal size and the type of precipitated scale due to temperature increase and agitation were also studied by SEM and EDX altogether at different time duration. Determination of the required velocity of injection in dynamic tests, kinetic of crystallization happening and the change in crystal size of calcium sulfate at different time duration are some of the applications of the results of this work.

Urban interfaces play a key role in enabling the different forms of social and economic exchange and the ways in which open space is contested and appropriated in informal settlements. Many upgrading practices involve a transformation of public/private interfaces. The transition between public and private territories is one of the critical issues in planning, urban design, and architecture that has the capacity to enable or constrain exchange and production. This paper develops a typology for analysing and mapping public/private interfaces in informal settlements. Drawing on the evidence from multiple case studies of informal settlements in Southeast Asia, South Asia, and South America, a typology of six interface types is introduced based on the criteria of proximity and connectivity. The study is informed by direct observation, visual recordings, and urban mapping to shed light on the ways in which urban interfaces work in informal settlements.

Background: North of Iran is amongst high incidence rate areas of gastric carcinoma where environmental carcinogenic compounds especially agricultural pesticides are massively used. Cytochrome P450 2E1 (CYP2E1) enzyme metabolically activates a large number of low molecular mass xenobiotics. The polymorphic nature of cyp2E1 gene control elements is associated with interindividual differences for toxicity of its substrates and may be responsible for increased gastric cancer susceptibility. The current study investigated the allelic frequencies of cyp2E1 gene RsaI/PstI polymorphisms and its association with gastric cancer risk in north of Iran. Materials and Methods: This case-control study comprised of 120 gastric cancer patients and a group of 135 healthy individuals as control. Genotyping of cyp2E1 gene PstI/RsaI polymorphisms were carried out by PCR-RFLP method. Statistical analyzes were performed by Logistic regression model and P

Molecular diffusion and mechanical dispersion are major factors affecting the concentration profiles during the miscible injection process. Solving the diffusivity equation always has some source of numerical error, which is called numerical dispersion. Reducing this error is the key parameter to studying the effect of diffusion and dispersion. In this article, a two-dimensional model has been generated and, according to diffusivity equation, the grid shapes have been defined depending on the front velocity of a grid’s position to reduce the numerical dispersion of the system. The predicted concentration profile by this method is in good agreement with the real concentration.

Informal settlements in cities of the global South are generally identified by a dense, small-grain and irregular urban morphology. Such neighbourhoods are rarely entered by those from the formal city and their visibility within the urban landscape can have a significant impact on decisions over whether and how they might be upgraded or demolished. This paper explores this issue from the perspective of the role of topography and urban morphology in mediating the gaze from the formal to the informal city. A simple typology of spatial visibility is developed according to whether the formal gaze is an overview or streetview, and whether it is private or public. This framework is then used to map the visibility of three case studies at district scale in the cities of Bangkok (Thailand), Pune (India) and Medellin (Colombia). These cases are then used to illustrate how different types and degrees of visibility are introduced or erased through different forms of urban design, transport infrastructure, high-rise development and public policy. We conclude by discussing different approaches to the transformation of place identity: concealing or revealing informal settlements on the one hand, and blurring or accentuating informal/formal distinctions on the other.

Background: Although some investigations have shown higher rates of successful first attempt and fewer attempts by using ultrasound-guided Internal Jugular Vein (IJV) catheterization, arterial puncture is still common.. Objectives: The present study aimed to investigate US-guided catheterization of the right IJV via medial-oblique technique and also compare this technique to short-axis technique in open-heart surgery patients.. Patients and Methods: In this randomized clinical trial, 80 patients referred to cardiac operating room of Namazi hospital, Shiraz, Iran from March to July 2014 were selected using census method. Block randomization with website was also done. Then, the patients were divided into two groups of 40, Short Axis Group (SAG) and Medial-Oblique Group (M-OG). For short-axis technique, patient’s head was positioned at zero degree angulation with his trunk. For medial-oblique technique, on the other hand, patient’s head was tilted to left to 45 degrees between the head and trunk. Sex, age, Body Mass Index (BMI), access time, guidewire time, cannulation time, total attempts for catheterization, first, second, and third attempt success, arterial puncture, hematoma, bleeding, and catheter malposition were recorded. The overlap between the carotid artery and IJV in zero- and 45-degree angulation was estimated through ultrasound print. After all, Kolmogorov-Smirnov test was used to assess normal distribution of the data. Then, the data were analyzed through Student’s t-test, Mann-Whitney U test, and chi-square test. P < 0.05 was considered as statistically significant.. Results: The results showed no significant differences between the two groups regarding the duration of different catheterization steps (P = 0.376). In all the cases in both groups, accessing the vein was successful with three attempts or less. There were no clinical complications of catheterization in the two groups. The mean of overlap was 23.60 ± 33.47 in zero-degree angulation between the head and trunk and 32.72 ± 36.38 in 45-degree angulation and this difference was statistically significant (P = 0.001).. Conclusions: The results of the present study showed that both US-guided techniques under investigation had the same duration in different catheterization steps, total success rate, and primary mechanical complications, and could be used in clinics..

Effect of proximity-induced superconductivity in the new two-dimensional structures, as graphene and topological insulator on the Andreev bound states (ABSs) and Josephson supercurrent has attracted much efforts. Motivated by this subject, we study, in particular, the influence of anisotropic Fermi velocity and unconventional d-wave pairing in a strained graphene-based superconductor/normal/ superconductor junction. Strain is applied in the zigzag direction of graphene sheet. In this process, effect of zero energy states and Fermi wavevector mismatch are investigated. It is shown, that strain up to 22% in graphene lattice differently affects Josephson currents in parallel and perpendicular directions of strain. Strain causes to exponentially decrease the supercurrent in the strain direction, whereas increase for other direction. We find that, in one hand, the ABSs strongly depend on strain and, on the other hand, a gap opens in the states with respect to non-zero incidence angle of quasiparticles, where a period of 2 π is obtained for Andreev states. Moreover, we observe no gap for θ s ≠ 0 , when the zero energy states (ZESs) occur in α = π / 4 due to anisotropic superconducting gap. In this case, ABSs have a period of 4 π .S

Background: Chest radiography after central venous catheter (CVC) insertion is the main method of verifying the catheter location. Despite the widespread use of radiography for detecting catheter position, x-ray may not always be readily available, especially in the operating room. Objectives: We aimed to compare contrast-enhanced ultrasonography (CEUS) and chest radiography for detecting the correct lo- cation of CVCs. Methods: One hundred sixteen consecutive patients with indications for CVC before cardiac surgery were enrolled in this observa- tional study. After catheter insertion, CEUS was performed. Portable radiography was obtained postoperatively in the intensive care unit. Sensitivity, specificity, and predictive values were determined by comparing the ultrasonography results with radiographic findings as a reference standard. Results: Chest radiography revealed 16 CVC misplacements: two cases of intravascular and 14 cases of right atrium (RA) misplace- ment. CEUS detected 11 true catheter malpositionings in the RA, while it could not recognize seven catheter placements correctly. CEUS showed two false RA misplacements and five falsely correct CVC positions. A sensitivity of 98% and specificity of 69% were achieved for CEUS in detecting CVC misplacements. Positive and negative predictive values were 95% and 85%, respectively. The interrater agreement (kappa) between CEUS and radiography was 0.72 (P < 0.001). Conclusions: Despite close concordance between ultrasonography and chest radiography, CEUS is not a suitable alternative for standard chest radiography in detecting CVC location; however, considering its high sensitivity and acceptable specificity in our study, its usefulness as a triage method for detecting CVC location on a real-time basis in the operating room cannot be ignored.

The last decade has seen an increasing interest in the application of assemblage thinking, in geography, sociology, and urban studies. Different interpretations of the Deleuzian concept of assemblage give rise to the multiple articulations of the term in urban studies so far. This paper aims to review the recently published research on assemblage theory and explore the implications of assemblage thinking in urban studies. The study thus provides an overview of the most significant contributions in the area, including a succinct bibliography on the subject. The paper concludes that assemblage can be effectively adopted as a way of thinking in urban studies to provide a theoretical lens for understanding the complexity of the city problems by emphasising the relations between sociality and spatiality at different scales.

Title on the accepted version is: Informal morphologies, Much has been made of the fact that most of the global population is now urban. It is not so often noted that most of this new urban population has been accommodated through the expansion of informal settlements or slums in the developing world. Informal architecture, urban design and planning are the primary means by which cities have absorbed most rural-to-urban migration over the past half-century. We define such settlements as ‘informal’ because they emerge outside the formal codes of the state in terms of land tenure, urban planning, design and construction. The label ‘informal’ is also used to avoid terms with overlapping meanings, like ‘slum’ and ‘squatter’. The distinctions between these three terms are important. Informal settlements can be defined as those where the design, planning and construction of buildings and street networks emerges without authorisation by the state (Roy and AlSayyad 2004). A slum is defined by the UN as a dwelling that lacks basic access to light, space, air, water, sanitation, security or durability (UN-Habitat 2006: 19). Squatting is settlement that occurs without the authorisation of the legal owner. Many dwellings within so-called ‘slums’ do not fit the UN definition and standards of construction can be quite high (Hernandez and Kellett 2010). Likewise, tenure is often ambiguous, irregular and contested, with many forms of de facto tenure (Durand-Lasserve and Royston 2002). Many informal settlements are established by ‘pirate’ developers on private land with quasi-legal tenure. Such ‘between’ conditions are typical: slums becoming upgraded; squatters becoming tenured; informal settlements becoming formalised; and formal settlements becoming informalised. Our thinking, analysis and action on this nexus of issues needs to move beyond the somewhat essentialised concepts of slums, squatters and informal settlements.

Psychiatric Research Center, Roozbeh Hospital, Tehran University of Medical Sciences, Tehran, IranObjectives Limited pharmacological options are available for the management of Alzheimer’s disease (AD) in severe stages. Cognitive-enhancing properties of saffron, the dried stigma of Crocus sativus L., have been evidenced in different studies. We aimed to compare theefficacy and safety of saffron extract versus memantine in reducing cognitive deterioration of patients with moderate to severe AD.Methods In this randomized double-blind parallel-group study, 68 patients with moderate to severe AD (Mini-Mental StateExamination scoreof8–14)receivedmemantine(20mg/day)orsaffronextract(30mg/da y)capsulesfor12months.Participantswereevaluatedeverymonth by Severe Cognitive Impairment Rating Scal e (SCIRS) and Functional Assessment Staging (FAST) in addition to recording the probableadverse events.Results Bothtreatmentgroupsshowedsimilaroutcomesasdemonstratedbyinsignificanteffectfortime×treatmentinteractiononSCIRSscores[F(2.95,194.78)=2.25, p=0.08].TherewasnosignificantdifferencebetweenthetwogroupsinthescoreschangesfrombaselinetotheendpointonSCIRS (p=0.38) and FAST (p=0.87). The frequency of adverse events was not signi ficantly different between the two groups as well.Conclusions In addition to its favorable safety profile, 1-year administration of saffron extract capsules showed to be comparable withmemantine in reducing cognitive decline in patients with moderate to severe AD. Confirmatory studies with larger sample sizes and longerfollow-up periods are warranted. Copyright © 2014 John Wiley & Sons, Ltd.key words—saffron; memantine; Alzheimer’s disease; Crocus sativus L.; glutamate

Informal urbanism, ranging from informal settlements to trading and transport, has become integral, but not limited, to the ways in which cities of the global South work. At stake here is the role of the built environment professions in responding to informal urbanism where a poor understanding of the complexities of informality can lead to poor design interventions. Providing a better understanding of how forms of informality work is then a key task for the built environment education, which arguably falls short in this regard. With a particular focus on urban design, we suggest that it is critical to move towards an informal turn in the built environment education to address informality and engage with the dynamics of informal urbanism. We first investigate the scope of urban design and then explore the ways in which urban design education can respond to informal urbanism in its curricula by developing an urban design program on informality as an illustration. The suggested approach can be considered as an initial step towards an informal turn in urban design education. We conclude that while urban design alone cannot solve social and economic problems, including poverty and inequality, its capacity to address the complex challenges of urbanization cannot be overlooked. Urban design education cannot remain isolated from the questions of informality anymore.

Addressing interactive and communicative aspects of design process, architectural pedagogy, and practices of urban education, collaborative design studio (CDS) has become a considerable area of interdisciplinary research in the past years. However, a growing body of knowledge in CDS studies shows that the criteria of evidence-based practices, empirical explorations, and theoretical conceptualization of CDS have not been addressed properly yet. Thus, adopting quantitative and qualitative approaches, the study tends to provide a conceptual framework for CDS studies and explore the interrelations between three parameters of the generated model through a case study of collaborative design studio in practice. Firstly, the study tends to conceptualize various dimensions of collaborative design studio based on the previous researches in terms of place, content, process, time, and size. Secondly, the study implements correlational research methods in terms of structural equation model (SEM) and factor analysis in order to explore interrelations between parameters of size, place, and process in a case study. In this way, findings of the study indicate that the parameter of size has significant influences on the process factor in CDS practices. Moreover, it suggests that the parameter of place is not likely to have considerable impact on the factor of process.

Various conceptions of pattern from biology, computer science, and mathematics to environmental design, psychology, and sociology give rise to the multiplicity of definitions, descriptions, applications, scales, and common features of spatial patterns in urban environments. Considering the complex relations between spatiality and sociality in place theory, the study tends to explore a growing body of knowledge in conceptions of urban crime and pattern. Placing the investigations of urban crime in relation to sociality and spatiality, the paper advocates for departuring from spatiality that is the common ground between urban crime and pattern conceptions. Hence, dismissing both deterministic and free-will approaches to environmental design and addressing the urban crime as a complex city problem, the study argues that adopting a kind of spatial knowledge and possibilistic approach is critical for both understanding and transforming the city in order to investigate the issue of urban crime in relation to spatial patterns.

Various dimensions and forces tend to transform urban housing morphology over time. These impacting elements do not equally contribute to the formation of dwellings. One of the main va-riables in urban housing is the sociocultural attributes that contribute to the morphological for-mation of different types of human habitats. The study focuses on the relations between sociocul-tural dimension and spatial configuration in terms of design process, transformation, and mor-phological attributes. Grounding a conceptual framework in a case study of vernacular housing in the cities of Ramsar and Tonekabon in Northern parts of Iran, the study explores the housing morphology of a vernacular dwelling. Implementing a qualitative approach, the research methods of the study consist of descriptive-analytical method, case study, and logical reasoning. Firstly, a conceptual framework is generated through desk study and non-participatory observation. Se-condly, housing typology, morphological mapping, and face-to-face interview have been conducted within the field study. Finally, the study explores the spatial configuration and morphology of the vernacular urban housing in relation to the conceptual framework. Findings indicate the complexity of relations between multilayered hierarchies of sociocultural factors and urban housing form in terms of physical form and spatial configuration in the case study of vernacular housing.