Search results for: native defects

Authors: T. S. Almutairi, Paul May, Neil Allan

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The geometrical, electronic and magnetic properties of the neutral Mg center and MgN₃ cluster in diamond have been studied theoretically in detail by means of an HSE06 Hamiltonian that includes a fraction of the exact exchange term; this is important for a satisfactory picture of the electronic states of open-shell systems. Another batch of the calculations by GGA functionals have also been included for comparison, and these support the results from HSE06. The local perturbations in the lattice by introduced Mg defect are restricted in the first and second shell of atoms before eliminated. The formation energy calculated with HSE06 and GGA of single Mg agrees with the previous result. We found the triplet state with C₃ᵥ is the ground state of Mg center with energy lower than the singlet with C₂ᵥ by ~ 0.1 eV. The recent experimental ZPL (557.4 nm) of Mg center in diamond has been discussed in the view of present work. The analysis of the band-structure of the MgN₃ cluster confirms that the MgN₃ defect introduces a shallow donor level in the gap lying within the conduction band edge. This observation is supported by the EMM that produces n-type levels shallower than the P donor level. The formation energy of MgN₂ calculated from a 2NV defect (~ 3.6 eV) is a promising value from which to engineer MgN₃ defects inside the diamond. Ion-implantation followed by heating to about 1200-1600°C might induce migration of N related defects to the localized Mg center. Temperature control is needed for this process to restore the damage and ensure the mobilities of V and N, which demands a more precise experimental study.

Keywords: empirical marker method, generalised gradient approximation, Heyd–Scuseria–Ernzerhof screened hybrid functional, zero phono line

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Authors: Marie-Claude Roy, David Locky, Ermias Azeria, Jim Schieck

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It is estimated that up to 70% of the wetlands in the Parkland and Grassland natural regions of Alberta have been lost due to various land-use activities. These losses include ecosystem function and services they once provided. Those wetlands remaining are often embedded in a matrix of human-modified habitats and despite efforts taken to protect them the effects of land-uses on wetland condition and function remain largely unknown. We used biophysical field data and remotely-sensed human footprint data collected at 322 open-water wetlands by the Alberta Biodiversity Monitoring Institute (ABMI) to evaluate the impact of surrounding land use on the physico-chemistry characteristics and plant functional traits of wetlands. Eight physio-chemistry parameters were assessed: wetland water depth, water temperature, pH, salinity, dissolved oxygen, total phosphorus, total nitrogen, and dissolved organic carbon. Three plant functional traits were evaluated: 1) origin (native and non-native), 2) life history (annual, biennial, and perennial), and 3) habitat requirements (obligate-wetland and obligate-upland). Intensity land-use was quantified within a 250-meter buffer around each wetland. Ninety-nine percent of wetlands in the Grassland and Parkland regions of Alberta have land-use activities in their surroundings, with most being agriculture-related. Total phosphorus in wetlands increased with the cover of surrounding agriculture, while salinity, total nitrogen, and dissolved organic carbon were positively associated with the degree of soft-linear (e.g. pipelines, trails) land-uses. The abundance of non-native and annual/biennial plants increased with the amount of agriculture, while urban-industrial land-use lowered abundance of natives, perennials, and obligate wetland plants. Our study suggests that land-use types surrounding wetlands affect the physicochemical and biological conditions of wetlands. This research suggests that reducing human disturbances through reclamation of wetland buffers may enhance the condition and function of wetlands in agricultural landscapes.

Keywords: wetlands, biophysical assessment, land use, grassland and parkland natural regions

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Authors: Anne Mette Nyvad, Ken Ramshøj Christensen

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In the syntax literature, it has standardly been assumed that relative clauses and complement wh-clauses are islands for extraction in English, and that constraints on extraction from syntactic islands are universal. However, the Mainland Scandinavian languages has been known to provide counterexamples. Previous research on Danish has shown that neither relative clauses nor embedded questions are strong islands in Danish. Instead, extraction from this type of syntactic environment is degraded due to structural complexity and it interacts with nonstructural factors such as the frequency of occurrence of the matrix verb, the possibility of temporary misanalysis leading to semantic incongruity and exposure over time. We argue that these facts can be accounted for with parametric variation in the availability of CP-recursion, resulting in the patterns observed, as Danish would then “suspend” the ban on movement out of relative clauses and embedded questions. Given that Danish does not seem to adhere to allegedly universal syntactic constraints, such as the Complex NP Constraint and the Wh-Island Constraint, what happens in L2 English? We present results from a study investigating how native Danish speakers judge extractions from island structures in L2 English. Our findings suggest that Danes transfer their native language parameter setting when asked to judge island constructions in English. This is compatible with the Full Transfer Full Access Hypothesis, as the latter predicts that Danish would have difficulties resetting their [+/- CP-recursion] parameter in English because they are not exposed to negative evidence.

Keywords: syntax, islands, second language acquisition, danish

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Authors: Akaki Qatamidze

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Implementation of the project will be a step forward in terms of reliability in Georgia and the improvement of the construction and the development of construction. Completion of the project is expected to result in a complete knowledge, which is expressed in concrete and stone structures of assessing the technical condition of the processing. This method is based on a detailed examination of the structure, in order to establish the injuries and the elimination of the possibility of changing the structural scheme of the new requirements and architectural preservationists. Reinforced concrete and stone structures research project carried out in a systematic analysis of the important approach is to optimize the process of research and development of new knowledge in the neighboring areas. In addition, the problem of physical and mathematical models of rational consent, the main pillar of the physical (in-situ) data and mathematical calculation models and physical experiments are used only for the calculation model specification and verification. Reinforced concrete and stone construction defects and failures the causes of the proposed research to enhance the effectiveness of their maximum automation capabilities and expenditure of resources to reduce the recommended system analysis of the methodological concept-based approach, as modern science and technology major particularity of one, it will allow all family structures to be identified for the same work stages and procedures, which makes it possible to exclude subjectivity and addresses the problem of the optimal direction. It discussed the methodology of the project and to establish a major step forward in the construction trades and practical assistance to engineers, supervisors, and technical experts in the construction of the settlement of the problem.

Keywords: building, reinforced concrete, expertise, stone structures

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Authors: Clive Sealey

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This article will analyse the impact that the increasingly multicultural nature of the UK has had on the nature and direction of social policy. The increasingly multicultural nature of the UK is being driven by a variety of demographic changes, particularly increased net migration from EU10 and the EU 2 enlargement. This has become an increasingly political issue, as exemplified by the specific rise of the United Kingdom Independence Party as a political force with the primary intention of restricting such migration. Perhaps not surprisingly, this has also had a significant impact on the nature and direction of social policies, as evident in the prominence given to efforts to reducing immigration and to restrict welfare benefits paid to such migrants. These policies have largely reflected the retreat away from the emphasis in UK policy on multiculturalism towards assimilation for all migrants, both prior and newly domiciled. Linking these two main policy emphases of reducing immigration and limiting entitlement to benefits is the concept of citizenship. An important point that this article will highlight, is that this changed citizenship does not just relate to new migrants, but also to existing domiciled migrants, such as in relation to specifying the assimilation of ‘Britishness’ and ‘British values’ in their daily life. Additionally, the article also analyses how the changes in welfare entitlements for new migrants is also impacting in an exclusionary way on the living standards of the native population, and therefore also their social rights as citizens. The article discusses the implication that this change presents for social work practice, particularly in terms of both migrants and native population changed citizenship.

Keywords: migration, citizenship, exclusion, social policy, migrant welfare

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Authors: Deepak Mohan, Sushma Sharma, Mohammad Asif

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Diclofenac sodium being one of the most common non-steroidal anti-inflammatory drugs is normally used as painkiller and to reduce inflammation. The drug is known to alter the enzymatic activities of acid and alkaline phosphatase, glutamate oxaloacetate transaminase and glutamate pyruvate transaminases. The drug also results in change in the concentration of proteins and lipids in the body. The present study is an attempt to study different biochemical changes electrophoretically due to administration of different doses of diclofenac (4mg/kg/body weight and 14mg/kg/body weight) on liver and testes of mice from 7-28 days of investigation. Homogenization of the tissue was done, supernatant separated was loaded in the gel and native polyacrylamide gel electrophoresis was conducted. Diclofenac administration resulted in alterations of all these biochemical parameters which were observed in native polyacrylamide gel electrophoretic studies. The severe degenerative changes as observed during later stages of the experiment showed correlation with increase or decrease in the activities of all the enzymes studied in the present investigation. Image analysis of gel in liver showed a decline of 7.4 and 5.3 % in low and high dose group after 7 days whereas a decline of 9.6 and 7.5% was registered after 28 days of investigation. Similar analysis for testis also showed an appreciable decline in the activity of alkaline phosphatase after 28 days. Gel analysis of serum was also performed to find a correlation in the enzymatic activities between the tissue and blood.

Keywords: diclofenac, inflammation, polyacrylamide, phosphatase

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Authors: Jayant Balaji Athavale, Sean Clarke

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Background: According to the WHO, every year, more than 700,000 people die by suicide, which is one person around every 45 seconds. Suicide is the fourth leading cause of death among 15 to 29-year-olds globally. The most common situations or life events that might cause suicidal thoughts are financial problems/unemployment, rejections, relationship breakups, sexual/substance abuse and mental illnesses. Mental/psychological weakness caused due to defects in one’s personality is one of the main reasons why people feel they cannot cope in such situations and contemplate suicide. A WHO Mental Health Action Plan 2013–2020 lists a 4-point strategy to enhance mental health by ‘implementing strategies for promotion and prevention in mental health.’ Methodology: With 40 years of spiritual research background, the team at the Maharshi University of Spirituality has studied the spiritual root causes that can significantly affect one’s mental health and the solutions to improve it. Results/Findings: According to spiritual science, the time and nature of death are mostly due to spiritual reasons. A person would mostly contemplate and attempt suicide when he is spiritually most vulnerable. Spiritual practice, as per universal principles, helps in protecting a person spiritually and prevents him from getting such thoughts of self-harm or acting upon them by controlling such impulses. The University has had much success in helping people to overcome the defects in their personalities, including those with suicidal thoughts, through spiritual practices such as chanting the Name of God and the Personality Defect Removal (PDR) process developed by the Author. Conclusion: If such techniques were taught in educational institutions, they could be simple yet effective self-help tools to prevent thoughts of suicide and enhance mental health and well-being.

Keywords: suicide, mental health, abuse, suicide prevention, personality defect removal

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Authors: Alireza Shams, Ali Zamanian, Atefehe Shamosi, Farnaz Ghorbani

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Introduction: Although the application of a new strategy remains a remarkable challenge for treatment of disabilities due to neuronal defects, progress in Nanomedicine and tissue engineering, suggesting the new medical methods. One of the promising strategies for reconstruction and regeneration of nervous tissue is replacing of lost or damaged cells by specific scaffolds after Compressive, ischemic and traumatic injuries of central nervous system. Furthermore, ultrastructure, composition, and arrangement of tissue scaffolds are effective on cell grafts. We followed implantation and differentiation of mesenchyme stem cells to neural cells on Gelatin Polylactic-co-glycolic acid (PLGA) scaffolds coated with iron nanoparticles. The aim of this study was to evaluate the capability of stem cells to differentiate into motor neuron-like cells under topographical cues and morphogenic factors. Methods and Materials: Bone marrow mesenchymal stem cells (BMMSCs) was obtained by primary cell culturing of adult rat bone marrow got from femur bone by flushing method. BMMSCs were incubated with DMEM/F12 (Gibco), 15% FBS and 100 U/ml pen/strep as media. Then, BMMSCs seeded on Gel/PLGA scaffolds and tissue culture (TCP) polystyrene embedded and incorporated by Fe Nano particles (FeNPs) (Fe3o4 oxide (M w= 270.30 gr/mol.). For neuronal differentiation, 2×10 5 BMMSCs were seeded on Gel/PLGA/FeNPs scaffolds was cultured for 7 days and 0.5 µ mol. Retinoic acid, 100 µ mol. Ascorbic acid,10 ng/ml. Basic fibroblast growth factor (Sigma, USA), 250 μM Iso butyl methyl xanthine, 100 μM 2-mercaptoethanol, and 0.2 % B27 (Invitrogen, USA) added to media. Proliferation of BMMSCs was assessed by using MTT assay for cell survival. The morphology of BMMSCs and scaffolds was investigated by scanning electron microscopy analysis. Expression of neuron-specific markers was studied by immunohistochemistry method. Data were analyzed by analysis of variance, and statistical significance was determined by Turkey’s test. Results: Our results revealed that differentiation and survival of BMMSCs into motor neuron-like cells on Gel/PLGA/FeNPs as a biocompatible and biodegradable scaffolds were better than those cultured in Gel/PLGA in absence of FeNPs and TCP scaffolds. FeNPs had raised physical power but decreased capacity absorption of scaffolds. Well defined oriented pores in scaffolds due to FeNPs may activate differentiation and synchronized cells as a mechanoreceptor. Induction effects of magnetic FeNPs by One way flow of channels in scaffolds help to lead the cells and can facilitate direction of their growth processes. Discussion: Progression of biological properties of BMMSCs and the effects of FeNPs spreading under magnetic field was evaluated in this investigation. In vitro study showed that the Gel/PLGA/FeNPs scaffold provided a suitable structure for motor neuron-like cells differentiation. This could be a promising candidate for enhancing repair and regeneration in neural defects. Dynamic and static magnetic field for inducing and construction of cells can provide better results for further experimental studies.

Keywords: differentiation, mesenchymal stem cells, nano particles, neuronal defects, Scaffolds

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Authors: Helga Heylen

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With dogs saving wildlife in New Zealand since 1890 and governments in Africa, Australia and Canada trusting them to give the best results, Conservation Dogs Ireland want to introduce more detection dogs to protect Europe's native wildlife. Conservation detection dogs are fast, portable and endlessly trainable. They are a cost-effective, highly sensitive and non-invasive way to detect protected and invasive species and wildlife disease. Conservation dogs find targets up to 40 times faster than any other method. They give results instantly, with near-perfect accuracy. They can search for multiple targets simultaneously, with no reduction in efficacy The European Red List indicates the decline in biodiversity has been most rapid in the past 50 years, and the risk of extinction never higher. Just two examples of major threats dogs are trained to tackle are: (I)Japanese Knotweed (Fallopia Japonica), not only a serious threat to ecosystems, crops, structures like bridges and roads - it can wipe out the entire value of a house. The property industry and homeowners are only just waking up to the full extent of the nightmare. When those working in construction on the roads move topsoil with a trace of Japanese Knotweed, it suffices to start a new colony. Japanese Knotweed grows up to 7cm a day. It can stay dormant and resprout after 20 years. In the UK, the cost of removing Japanese Knotweed from the London Olympic site in 2012 was around £70m (€83m). UK banks already no longer lend on a house that has Japanese Knotweed on-site. Legally, landowners are now obliged to excavate Japanese Knotweed and have it removed to a landfill. More and more, we see Japanese Knotweed grow where a new house has been constructed, and topsoil has been brought in. Conservation dogs are trained to detect small fragments of any part of the plant on sites and in topsoil. (II)Zebra mussels (Dreissena Polymorpha) are a threat to many waterways in the world. They colonize rivers, canals, docks, lakes, reservoirs, water pipes and cooling systems. They live up to 3 years and will release up to one million eggs each year. Zebra mussels attach to surfaces like rocks, anchors, boat hulls, intake pipes and boat engines. They cause changes in nutrient cycles, reduction of plankton and increased plant growth around lake edges, leading to the decline of Europe's native mussel and fish populations. There is no solution, only costly measures to keep it at bay. With many interconnected networks of waterways, they have spread uncontrollably. Conservation detection dogs detect the Zebra mussel from its early larvae stage, which is still invisible to the human eye. Detection dogs are more thorough and cost-effective than any other conservation method, and will greatly complement and speed up the work of biologists, surveyors, developers, ecologists and researchers.

Keywords: native biodiversity, conservation detection dogs, invasive species, Japanese Knotweed, zebra mussel

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Authors: Jaan Lellep, Shahid Mubasshar

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A numerical solution is developed for simply supported nanoarches based on the non-local theory of elasticity. The nanoarch under consideration has a step-wise variable cross-section and is weakened by crack-like defects. It is assumed that the cracks are stationary and the mechanical behaviour of the nanoarch can be modeled by Eringen’s non-local theory of elasticity. The physical and thermal properties are sensitive with respect to changes of dimensions in the nano level. The classical theory of elasticity is unable to describe such changes in material properties. This is because, during the development of the classical theory of elasticity, the speculation of molecular objects was avoided. Therefore, the non-local theory of elasticity is applied to study the vibration of nanostructures and it has been accepted by many researchers. In the non-local theory of elasticity, it is assumed that the stress state of the body at a given point depends on the stress state of each point of the structure. However, within the classical theory of elasticity, the stress state of the body depends only on the given point. The system of main equations consists of equilibrium equations, geometrical relations and constitutive equations with boundary and intermediate conditions. The system of equations is solved by using the method of separation of variables. Consequently, the governing differential equations are converted into a system of algebraic equations whose solution exists if the determinant of the coefficients of the matrix vanishes. The influence of cracks and steps on the natural vibration of the nanoarches is prescribed with the aid of additional local compliance at the weakened cross-section. An algorithm to determine the eigenfrequencies of the nanoarches is developed with the help of computer software. The effects of various physical and geometrical parameters are recorded and drawn graphically.

Keywords: crack, nanoarches, natural frequency, step

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Authors: Ruchi Pathania, Ahmad Ahmad, Shireesh Srivastava

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Cyanobacteria is a promising microbe that can capture and convert atmospheric CO₂ and light into valuable industrial bio-products like biofuels, biodegradable plastics, etc. Among their most attractive traits are faster autotrophic growth, whole year cultivation using non-arable land, high photosynthetic activity, much greater biomass and productivity and easy for genetic manipulations. Cyanobacteria store carbon in the form of glycogen which can be hydrolyzed to release glucose and fermented to form bioethanol or other valuable products. Marine cyanobacterial species are especially attractive for countries with scarcity of freshwater. We recently identified a marine native cyanobacterium Synechococcus sp. BDU 130192 which has good growth rate and high level of polyglucans accumulation compared to Synechococcus PCC 7002. In this study, firstly we sequenced the whole genome and the sequences were annotated using the RAST server. Genome scale metabolic model (GSMM) was reconstructed through COBRA toolbox. GSMM is a computational representation of the metabolic reactions and metabolites of the target strain. GSMMs construction through the application of Flux Balance Analysis (FBA), which uses external nutrient uptake rates and estimate steady state intracellular and extracellular reaction fluxes, including maximization of cell growth. The model, which we have named isyn942, includes 942 reactions and 913 metabolites having 831 metabolic, 78 transport and 33 exchange reactions. The phylogenetic tree obtained by BLAST search revealed that the strain was a close relative of Synechococcus PCC 7002. The flux balance analysis (FBA) was applied on the model iSyn942 to predict the theoretical yields (mol product produced/mol CO₂ consumed) for native and non-native products like acetone, butanol, etc. under phototrophic condition by applying metabolic engineering strategies. The reported strain can be a viable strain for biotechnological applications, and the model will be helpful to researchers interested in understanding the metabolism as well as to design metabolic engineering strategies for enhanced production of various bioproducts.

Keywords: cyanobacteria, flux balance analysis, genome scale metabolic model, metabolic engineering

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Authors: Robert H. Bradley

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Many minority adolescents in the United States live in adverse circumstances that pose long-term threats to their well-being. A strong sense of personal control and self-efficacy can help youth mitigate some of those risks and may help protect youth from influences connected with deviant peer groups. Accordingly, it is important to identify conditions that help foster feelings of efficacy in areas that seem critical for the accomplishment of developmental tasks during adolescence. The purpose of this study is to examine two aspects of the home environment (modeling and encouragement of maturity, family companionship and investment) and their relation to three components of self efficacy (self efficacy in enlisting social resources, self efficacy for engaging in independent learning, and self-efficacy for self-regulatory behavior) in three groups of minority adolescents (Native American, African American, Latino). The sample for this study included 54 Native American, 131 African American, and 159 Latino families, each with a child between 16 and 20 years old. The families were recruited from four states: Arizona, Arkansas, California, and Oklahoma. Each family was administered the Late Adolescence version of the Home Observation for Measurement of the Environment (HOME) Inventory and each adolescent completed a 30-item measure of perceived self-efficacy. Three areas of self-efficacy beliefs were examined for this study: enlisting social resources, independent learning, and self-regulation. Each of the three areas of self-efficacy was regressed on the two aspects of the home environment plus overall household risk. For Native Americans, modeling and encouragement were significant for self-efficacy pertaining to enlisting social resources and independent learning. For African Americans, companionship and investment was significant in all three models. For Latinos, modeling and encouragement was significant for self-efficacy pertaining to enlisting social resources and companionship and investment were significant for the other two areas of self-efficacy. The findings show that even as minority adolescents are becoming more individuated from their parents, the quality of experiences at home continues to be associated with their feelings of self-efficacy in areas important for adaptive functioning in adult life. Specifically, individuals can develop a sense that they are efficacious in performing key tasks relevant to work, social relationships, and management of their own behavior if they are guided in how to deal with key challenges and they have been exposed and supported by others who are competent in dealing with such challenges. The findings presented in this study would seem useful given that there is so little current research on home environmental factors connected to self-efficacy beliefs among adolescents in the three groups examined. It would seem worthwhile that personnel from health, human service and juvenile justice agencies give attention to supporting parents in communicating with adolescents, offering expectations to adolescents in mutually supportive ways, and in engaging with adolescents in productive activities. In comparison to programs for parents of young children, there are few specifically designed for parents of children in middle childhood and adolescence.

Keywords: family companionship, home environment, household income, modeling, self-efficacy

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Authors: Shamsher Singh

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The Diaspora Literature involves a concept of native land, from where the displacement occurs and a record of harsh journeys undertaken on account of economic compulsions. Basically, Diaspora is a splintered community living in eviction. The scattering (initially) signifies the location of a fluid human autonomous space involving a complex set of negotiations and exchange between the nostalgia and desire for the native land and the making of a new home, adapting to the relationships between the minority and majority, being spokes persons for minority rights and their people back native place and significantly transacting the Contact Zone - a space changed with the possibility of multiple challenges. They write in the background of the sublime qualities of their homeland and, at the same time, try to fit themselves into the traditions and cultural values of other strange communities or land. It also serves as an interconnection of the various cultures involved, and it is used to understand the customs of different cultures and countries; it is also a source of inspiration globally. Although diasporic literature originated back in the 20th century, it spread to other countries like Britain, Canada, America, Denmark, Netherland, Australia, Kenya, Sweden, Kuwait and different parts of Europe. Meaning of Diaspora is the combination of two words which means the movement of people away from their own country or motherland. From a historical point of view, the ‘Diaspora’ is often associated with Jewish bigotry. At the moment, the Diaspora is used for the dispersal of social or cultural groups. This group will be living in two different streams of cultures at the same time. One who left behind his culture and the other has to adapt himself to new cultural situations. The diasporic mind hangs between his birth land and place of work at the same time. A person’s mental state, living in dual existence, gives birth to Dysphoria sensation. Litterateurs had different experiences in this type of sensation e.g., social, universal, political, economic and experiences from the strange land. The struggle of these experiences is seen in diasporic literature. When a person moves to different land or country to fulfill his dreams, the discrimination of language, work and other difficulties with strangers make his relationship more emotional and deeper into his past. These past memories and relations create more difficulties in settling in a foreign land. He lives there physically, but his mental state is in his past constantly, and he ends up his life in those background memories. A person living in Diaspora is actually a dual visionary man. Although this double vision expands his global consciousness, due to this vision, he gains judgemental qualities to understand others. At the same time, he weighs his respect for his native land and the situations of foreign land he experiences, and he finds it difficult to survive in those conditions. It can be said that diaspora literature indicates a person or social organization who lives dual life inquisition structure which becomes the cause of diasporic literature.

Keywords: homeland sickness, language problem, quest for identity, materialistic desire

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Authors: Samantha Meyr, Eman Mirdamadi, Martha Wang, Tao Lowe, Ryan Smith, Quinn Burke

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Critical-sized bone defects (CSD) treatment options remain a major clinical orthopedic challenge. They are uniquely contoured diseased or damaged bones and can be defined as those that will not heal spontaneously and require surgical intervention. Autografts are the current gold standard CSD treatment, which are histocompatible and provoke a minimal immunogenic response; however, they can cause donor site morbidity and will not suffice for the size required for replacement. As an alternative to traditional surgical methods, bone tissue engineering will be implemented via 3D printing methods. A freeze-dried bone matrix (FDBM) is a type of graft material available but will only function as desired when in the presence of bone growth factors. Polycaprolactone (PCL) is a known biodegradable material with good biocompatibility that has been proven manageable in 3D printing as a medical device. A 3D-extrusion printing strategy is introduced to print these materials into scaffolds for bone grafting purposes, which could be more accessible and rapid than the current standard. Mechanical, thermal, cytotoxic, and physical properties were investigated throughout a degradation period of 6 months using fibroblasts and dental pulp stem cells. PCL-FDBM scaffolds were successfully printed with high print fidelity in their respective pore sizes and allograft content. Additionally, we have created a method for evaluating PCL using differential scanning calorimetry (DSC) and have evaluated PCL degradation over roughly 6 months.

Keywords: 3D printing, bone tissue engineering, cytotoxicity, degradation, scaffolds

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Authors: John Rosswell Cummings III

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This research examines the discourse ancient Maya ritual practice manifest and maintained through language in a contemporary society as led by a daykeeper— a Maya spiritual leader— with the objective of discovering if the Maya Calendar has an influence on worldview. Through an ethnography of communication and discursive analysis framework, this research examines the discourse of and around the Maya calendar through original research. Data collected includes the ceremonial performance of the Tzolkin ritual, a ritual that takes place every 13 days to ceremonially welcome one of the 20 Universal Forces. During the ceremony, participants supplicate, sacrifice, and venerate. This ritual, based off the Tzolkin cycle in the Mayan Calendar, contains strong, culture-binding ideologies. This research performs a close analysis of the 20 energies of the Tzolkin and their glyphs so as to gain a better understanding of current ideologies in Maya communities. Through a linguistic relativity frame of reference, including both the strong and weak versions, the 20 Universal Forces are shown to influence ways of life. This research argues that it is not just the native language, but the discourses native to the community as held through the calendar, influence thought and have the potential to offer an alternate worldview, thus shaping the cultural narrative which in return influences identity of the community. Research of this kind, on calendric systems and linguistic relativity, has the power to make great discoveries about the societies of the world and their worldviews.

Keywords: anthropological linguistics, discourse analysis, cultural studies, sociolinguistics

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Authors: Chandeera Gunawardena

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The present research analyzes the pronunciation errors encountered by thirty Sinhala speaking learners of French on the assumption that the pronunciation errors were systematic and they reflect the interference of the native language of the learners. The thirty participants were selected using random sampling method. By the time of the study, the subjects were studying French as a foreign language for their Bachelor of Arts Degree at University of Kelaniya, Sri Lanka. The participants were from a homogenous linguistics background. All participants speak the same native language (Sinhala) thus they had completed their secondary education in Sinhala medium and during which they had also learnt French as a foreign language. A battery operated audio tape recorder and a 120-minute blank cassettes were used for recording. A list comprised of 60 words representing all French phonemes was used to diagnose pronunciation difficulties. Before the recording process commenced, the subjects were requested to familiarize themselves with the words through reading them several times. The recording was conducted individually in a quiet classroom and each recording approximately took fifteen minutes. Each subject was required to read at a normal speed. After the completion of recording, the recordings were replayed to identify common errors which were immediately transcribed using the International Phonetic Alphabet. Results show that Sinhala speaking learners face problems with French nasal vowels and French initial consonants clusters. The learners also exhibit errors which occur because of their second language (English) interference.

Keywords: error analysis, pronunciation difficulties, pronunciation errors, Sinhala speaking learners of French

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Authors: Mohammad Sharifi Bohlouli

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Turkish language with many dialects is native or official language of great number of people all around the world. The Qashqaie dialect of Turkish language is spoken by the Qashqaie tribe mostly scattered in the southern part of Iran. This paper aims at analyzing the tense system of this dialect to detect the type and number of tense and aspects available to its speakers. To collect a reliable data, a group of 50 old native speakers were randomly chosen as the informants and different techniques such as; Shuy et al interviews, selective listening ,and eavesdropping were used. The results of data analysis showed that the tense system in the Qashqaie dialect of Turkish language includes 3 absolute tenses , 6 aspectual , and 2 subjunctive ones. The interesting part of the study is that Qashqaie dialect enables its speakers to make a kind of aspectual opposition through verb structure which seems to be almost impossible through verb forms in any other nonturkish languages. For example in the following examples sentences 1 &2 and 3&4 have the same translation In English although they are different in both meaning and structure. 1. Ali ensha yazirdi. 2. Ali ensha yazirmush. (Ali was writing a composition.) 3. Ali yadmishdi. 4. Ali yadmishimish. ( Ali had slept.) The changes in the verb structure in Qashqaie dialect enables its speakers to say that whether the doer of the action remembers the process of doing the action or not. So, it presents a new aspectual opposition as Observed /nonobserved. The research findings reveal many other regularities and linguistic features that can be useful for linguists interested in Turkish in general and for those interested in tense and aspect and also they can be helpful for different pedagogical purposes including teaching and translating.

Keywords: qashqaie dialect, tense, aspect, linguistics, Turkish Language

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Authors: Tayebeh Norouzi

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This study aims to investigate the acquisition process of intonation. It examines the intonation structure of Tokyo Japanese and its realization by Iranian learners of Japanese. Seven Iranian learners of Japanese, differing in fluency, and two Japanese speakers participated in the experiment. Two sentences were used to test the phonological and phonetic characteristics of lexical pitch-accent as well as the intonation patterns produced by the speakers. Both sentences consisted of similar words with the same number of syllables and lexical pitch-accents but different syntactic structure. Speakers were asked to read each sentence three times at normal speed, and the data were analyzed by Praat. The results show that lexical pitch-accent, Accentual Phrase (AP) and AP boundary tone realization vary depending on sentence type. For sentences of type XdeYwo, the lexical pitch-accent is realized properly. However, there is a rise in AP boundary tone regardless of speakers’ level of fluency. In contrast, in sentences of type XnoYwo, the lexical pitch-accent and AP boundary tone vary depending on the speakers’ fluency level. Advanced speakers are better at grouping words into phrases and produce more native-like intonation patterns, though they are not able to realize downstep properly. The non-native speakers tried to realize proper intonation patterns by making changes in lexical accent and boundary tone.

Keywords: intonation, Iranian learners, Japanese prosody, lexical accent, second language acquisition.

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Authors: Mairo Musa Galadima

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This paper examines the impact of Mother tongue interference on students’ performance in English Language in Bauchi State. It is observed that the students of Bauchi district share the same problem with Hausa native speakers of Kano dialect which is the standard form. It is observed that there are some phonemes which are present in English but absent in Hausa so the Hausa speakers of Bauchi district also replace these sounds with similar ones present in Hausa. Students in Bauchi district fail English language because they transfer features of their mother tongue (MT) into English. The data is obtained through unobtrusive observation of the English speech of about fifty Hausa native speakers of Bauchi district which is similar to Kano dialect from Abubakar Tatari Ali Polytechnic, Bauchi since only those who have had some good background of secondary education are used because uneducated Nigeria English of whatever geographical location is more likely to be unintelligible as cockney or uneducated African-American English. For instance /Ə:/ is absent in Hausa so the speakers find it difficult to distinguish between such pairs of words as /bƏ:d / and /bΛst/, /fa:st/ and /fƏ:st / hence /a:/ is generally used wherever /Ə:/ is present regardless of the spelling, that is why words like ‘work’, ‘first’ and ‘person’ all have / a:/. In Hausa most speakers use /P/ in place of, or in alternation with /f/, e.g. ‘few’ is pronounced as ‘pew’, or ‘pen’, as ‘fen’, /b/ for /v/, /s/ for /z/ and /z/ for /ᵹ/. Also the word vision/visn/ is pronounced as /vidzn/. Therefore, there is confusion in spellings and pronunciation of words. One solution out of the problem is having constant practice with a qualified consistent staff and making use of standard textbooks in the learning process.

Keywords: English, failure, mother tongue, interference, students

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Authors: Chrysoula Karathanasi, Senad Karavdic, Angela Odero, Michèle Baumann

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It is not only the economic determinants that impact on life conditions, but maintaining a good level of life satisfaction (LS) may also be an important challenge currently. In Luxembourg, university students receive financial aid from the government. They are then registered at the Centre for Documentation and Information on Higher Education (CEDIES). Luxembourg is built on migration with almost half its population consisting of foreigners. It is upon this basis that our research aims to analyze the associations with mental health factors (health satisfaction, psychological quality of life, worry), perceived financial situation, career attitudes (adaptability, optimism, knowledge, planning) and LS, for non-Luxembourgish and native postgraduate students. Between 2012 and 2013, postgraduates registered at CEDIES were contacted by post and asked to participate in an online survey with either the option of English or French. The study population comprised of 644 respondents. Our statistical analysis excluded: those born abroad who had Luxembourgish citizenship, or those born in Luxembourg who did not have citizenship. Two groups were formed one consisting 147 non-Luxembourgish and the other 284 natives. A single item measured LS (1=not at all satisfied to 10=very satisfied). Bivariate tests, correlations and multiple linear regression models were used in which only significant relationships (p<0.05) were integrated. Among the two groups no differences were found between LS indicators (7.8/10 non-Luxembourgish; 8.0/10 natives) as both were higher than the European indicator of 7.2/10 (for 25-34 years). In the case of non-Luxembourgish students, they were older than natives (29.3 years vs. 26.3 years) perceived their financial situation as more difficult, and a higher percentage of their parents had an education level higher than a Bachelor's degree (father 59.2% vs 44.6% for natives; mother 51.4% vs 33.7% for natives). In addition, the father’s education was related to the LS of postgraduates and the higher was the score, the greater was the contribution to LS. Whereas for native students, when their scores of health satisfaction and career optimism were higher, their LS’ score was higher. For both groups their LS was linked to mental health-related factors, perception of their financial situation, career optimism, adaptability and planning. The higher the psychological quality of life score was, the greater the LS of postgraduates’ was. Good health and positive attitudes related to the job market enhanced their LS indicator.

Keywords: career attributes, father's education level, life satisfaction, mental health

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Authors: Indira Kothalanka

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For individuals born with a cleft palate (CP), there is no separation between the nasal cavity and the oral cavity, due to which they cannot build up enough air pressure in the mouth for speech. Therefore, it is common for them to have speech problems. Common cleft type speech errors include abnormal articulation (compensatory or obligatory) and abnormal resonance (hyper, hypo and mixed nasality). These are generally resolved after palate repair. However, in some individuals, articulation problems do persist even after the palate repair. Such individuals develop variant articulations in an attempt to compensate for the inability to produce the target phonemes. A spectrographic analysis is used to investigate the compensatory articulatory behaviours of pressure consonants in the speech of 10 Telugu speaking individuals aged between 7-17 years with a history of cleft palate. Telugu is a Dravidian language which is spoken in Andhra Pradesh and Telangana states in India. It is a language with the third largest number of native speakers in India and the most spoken Dravidian language. The speech of the informants is analysed using single word list, sentences, passage and conversation. Spectrographic analysis is carried out using PRAAT, speech analysis software. The place and manner of articulation of consonant sounds is studied through spectrograms with the help of various acoustic cues. The types of compensatory articulation identified are glottal stops, palatal stops, uvular, velar stops and nasal fricatives which are non-native in Telugu.

Keywords: cleft palate, compensatory articulation, spectrographic analysis, PRAAT

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Authors: R. Janyaphadungpong, A. Pimkhaokham

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This prospective clinical study determined the insertion torque (IT) value and monitored the changes in implant stability quotient (ISQ) values during the 12 weeks healing period from implant placement without bone graft (control group) and with bone graft using the guided bone regeneration (GBR) technique (study group). The relationship between the IT and ISQ values of the implants was also assessed. The control and study groups each consisted of 6 patients with 8 implants per group. The ASTRA TECH Implant System™ EV 4.2 mm in diameter was placed in the posterior mandibular region. In the control group, implants were placed in bone without bone graft, whereas in the study group implants were placed simultaneously with the GBR technique at favorable bone defect. IT (Ncm) of each implant was recorded when fully inserted. ISQ values were obtained from the Osstell® ISQ at the time of implant placement, and at 2, 4, 8, and 12 weeks. No difference in IT was found between groups (P = 0.320). The ISQ values in the control group were significantly higher than in the study group at the time of implant placement and at 4 weeks. There was no significant association between IT and ISQ values either at baseline or after the 12 weeks. At 12 weeks of healing, the control and study groups displayed different trends. Mean ISQ values for the control group decreased over the first 2 weeks and then started to increase. ISQ value increases were statistically significant at 8 weeks and later, whereas mean ISQ values in the study group decreased over the first 4 weeks and then started to increase, with statistical significance after 12 weeks. At 12 weeks, all implants achieved osseointegration with mean ISQ values over the threshold value (ISQ>70). These results indicated that implants, in which guided bone regeneration technique was performed during implant placement for treating favorable bone defects, were as predictable as implants placed without bone graft. However, loading in implants placed with the GBR technique for correcting favorable bone defects should be performed after 12 weeks of healing to ensure implant stability and osseointegration.

Keywords: dental implant, favorable bone defect, guided bone regeneration technique, implant stability

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Authors: Xinxin Ma, Guangze Tang, Shuxin Yang, Jinguang He, Fan Zhang, Peiling Sun, Ming Liu, Minyu Sun, Liqin Wang

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As a traditional surface hardening technique, shot peening is widely used in industry. By using shot peening, a residual compressive stress is formed in the surface which is beneficial for improving the fatigue life of metal materials. At the same time, very fine grains and high density defects are generated in the surface layer which enhances the surface hardness, either. However, most of the processes are carried out at room temperature. For high strength steel, such as M50, the thickness of the strengthen layer is limited. In order to obtain a thick strengthen surface layer, elevated temperature shot peening was carried out in this work by using Φ1mm cast ion balls with a speed of 80m/s. Considering the tempering temperature of M50 steel is about 550 oC, the processing temperature was in the range from 300 to 500 oC. The effect of processing temperature and processing time of shot peening on distribution of residual stress and surface hardness was investigated. As we known, the working temperature of M50 steel can be as high as 315 oC. Because the defects formed by shot peening are unstable when the working temperature goes higher, it is worthy to understand what happens during the shot peening process, and what happens when the strengthen samples were kept at a certain temperature. In our work, the shot peening time was selected from 2 to 10 min. And after the strengthening process, the samples were annealed at various temperatures from 200 to 500 oC up to 60 h. The results show that the maximum residual compressive stress is near 900 MPa. Compared with room temperature shot peening, the strengthening depth of 500 oC shot peening sample is about 2 times deep. The surface hardness increased with the processing temperature, and the saturation peening time decreases. After annealing, the residual compressive stress decreases, however, for 500 oC peening sample, even annealing at 500 oC for 20 h, the residual compressive stress is still over 600 MPa. However, it is clean to see from SEM that the grain size of surface layers is still very small.

Keywords: shot peening, M50 steel, residual compressive stress, elevated temperature

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Authors: Azin Shakibabarough, Mojtaba Valinejadshoubi, Ashutosh Bagchi

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Catastrophic bridge failure happens due to the lack of inspection, lack of design and extreme events like flooding, an earthquake. Bridge Management System (BMS) is utilized to diminish such an accident with proper design and frequent inspection. Visual inspection cannot detect any subsurface defects, so using Non-Destructive Evaluation (NDE) techniques remove these barriers as far as possible. Among all NDE techniques, Ground Penetrating Radar (GPR) has been proved as a highly effective device for detecting internal defects in a reinforced concrete bridge deck. GPR is used for detecting rebar location and rebar corrosion in the reinforced concrete deck. GPR profile is composed of hyperbola series in which sound hyperbola denotes sound rebar and blur hyperbola or signal attenuation shows corroded rebar. Interpretation of GPR images is implemented by numerical analysis or visualization. Researchers recently found that interpretation through visualization is more precise than interpretation through numerical analysis, but visualization is time-consuming and a highly subjective process. Automating the interpretation of GPR image through visualization can solve these problems. After interpretation of all scans of a bridge, condition assessment is conducted based on the generated corrosion map. However, this such a condition assessment is not objective and precise. Condition assessment based on structural integrity and strength parameters can make it more objective and precise. The main purpose of this study is to present an automated interpretation method of a reinforced concrete bridge deck through a visualization technique. In the end, the combined analysis of the structural condition in a bridge is implemented.

Keywords: bridge condition assessment, ground penetrating radar, GPR, NDE techniques, visualization

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Authors: Randa Alahmadi

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Because the world has become a global village, English is not only used by native speakers, but also by non-native speakers from culturally diverse backgrounds. Even though learning a second/foreign language requires development of the four skills: reading, writing, listening, and speaking, there is also an intertwined relationship between language and culture, making it difficult to teach language without knowing the cultural context in which it is to be used. In the past decade, the number of international students enrolled in universities around the world has increased significantly. Having the urge to communicate effectively would serve as a motivation for both international and domestic students. The teaching of culture is important because linguistic competence is not enough for successful communication with speakers of other languages. Therefore, whether teaching natives or non-natives, students need to improve their cross-cultural communication skills and become culturally prepared to communicate successfully with people from other cultures. Teachers can equip their students for this environment by giving them appropriate knowledge and skills for effective intercultural communication. This paper will focus on the importance of intercultural communicative competence and its role in developing students’ understanding of diverse cultures as part of learning foreign/second languages. It will also explain how teachers can decide which culture should be taught: the target culture, the learners’ culture, or both. Moreover, practical and effective techniques that can be used in cultural-based language teaching will be shared.

Keywords: cultural-based language teaching, English as a lingua franca, English language learners, intercultural communicative competence

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Authors: Nabil Al-Zaqri

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Semiconductor photocatalysts with surface defects display incredible light absorption bandwidth, and these defects function as highly active sites for oxidation processes by interacting with the surface band structure. Accordingly, engineering the photocatalyst with surface oxygen vacancies will enhance the semiconductor nanostructure's photocatalytic efficiency. Herein, a CeO2₋ₓ nanostructure is designed under the influence of low-frequency ultrasonic waves to create surface oxygen vacancies. This approach enhances the photocatalytic efficiency compared to many heterostructures while keeping the intrinsiccrystal structure intact. Ultrasonic waves induce the acoustic cavitation effect leading to the dissemination of active elements on the surface, which results in vacancy formation in conjunction with larger surface area and smaller particle size. The structural analysis of CeO₂₋ₓ revealed higher crystallinity, as well as morphological optimization, and the presence of oxygen vacancies is verified through Raman, X-rayphotoelectron spectroscopy, temperature-programmed reduction, photoluminescence, and electron spinresonance analyses. Oxygen vacancies accelerate the redox cycle between Ce₄+ and Ce₃+ by prolongingphotogenerated charge recombination. The ultrasound-treated pristine CeO₂ sample achieved excellenthydrogen production showing a quantum efficiency of 1.125% and efficient organic degradation. Ourpromising findings demonstrated that ultrasonic treatment causes the formation of surface oxygenvacancies and improves photocatalytic hydrogen evolution and pollution degradation. Conclusion: Defect engineering of the ceria nanoparticles with oxygen vacancies was achieved for the first time using low-frequency ultrasound treatment. The U-CeO₂₋ₓsample showed high crystallinity, and morphological changes were observed. Due to the acoustic cavitation effect, a larger surface area and small particle size were observed. The ultrasound treatment causes particle aggregation and surface defects leading to oxygen vacancy formation. The XPS, Raman spectroscopy, PL spectroscopy, and ESR results confirm the presence of oxygen vacancies. The ultrasound-treated sample was also examined for pollutant degradation, where 1O₂was found to be the major active species. Hence, the ultrasound treatment influences efficient photocatalysts for superior hydrogen evolution and an excellent photocatalytic degradation of contaminants. The prepared nanostructure showed excellent stability and recyclability. This work could pave the way for a unique post-synthesis strategy intended for efficient photocatalytic nanostructures.

Keywords: surface defect, CeO₂₋ₓ, photocatalytic, water treatment, H₂ production

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Authors: Jacqueline Kunzelman, Val Anderson, Robert Johnson, Nicholas Anderson, Rebecca Bates

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In an effort to protect honeybees from colony collapse disorder, beekeepers are filing for government permits to use natural lands as summer pasture for honeybees under the multiple-use management regime in the United States. Utilizing natural landscapes in high mountain ranges may help strengthen honeybee colonies, as this natural setting is generally void of chemical pollutants and pesticides that are found in agricultural and urban settings. However, the introduction of a competitive species could greatly impact the native species occupying these natural landscapes. While honeybees and butterflies have different life histories, behavior, and foraging strategies, they compete for the same nectar resources. Few, if any, studies have focused on the potential population effects of commercial honeybees on native butterfly abundance and diversity. This study attempts to observe this impact using a paired before-after control-impact (BACI) design. Over the course of two years, malaise trap samples were collected every week during the months of the flowering season in two similar areas separated by 11 kilometers. Each area contained nine malaise trap sites for replication. In the first year, samples were taken to analyze and establish trends within the pollinating communities. In the second year, honeybees were introduced to only one of the two areas, and a change in trends between the two areas was assessed. Contrary to the original hypothesis, the resulting observation was an overall significant increase in the mean butterfly abundance in the impact areas after honeybees were introduced, while control areas remained relatively stable. This overall increase in abundance over the season can be attributed to an increase in butterflies during the first and second periods of the data collection when populations were near their peak. Several potential theories are 1) Honeybees are deterring a natural predator/competitor of butterflies that previously limited population growth. 2) Honeybees are consuming resources regularly used by butterflies, which may extend the foraging time and consequent capture rates of butterflies. 3) Environmental factors such as number of rainy days were inconsistent between control and impact areas, biasing capture rates. This ongoing research will help determine the suitability of high mountain ranges for the summer pasturing of honeybees and the population impacts on many different pollinators.

Keywords: butterfly, competition, honeybee, pollinator

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Authors: Mohammad Sharifi Bohlouli, Elnaz Sharifi Bohlouli

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Turkish language with many dialects is native or official language of great number of people all around the world. The Qashqaie dialect of Turkish language is spoken by the Qashqaie tribe mostly scattered in the southern part of Iran. This paper aims at analyzing the tense system of this dialect to detect the type and number of tense and aspects available to its speakers. To collect a reliable data, a group of 50 old native speakers were randomly chosen as the informants and different techniques such as; Shuy et al interviews, selective listening ,and eavesdropping were used. The results of data analysis showed that the tense system in the Qashqaie dialect of Turkish language includes 3 absolute tenses, 6 aspectual, and 2 subjunctive ones. The interesting part of the study is that Qashqaie dialect enables its speakers to make a kind of aspectual opposition through verb structure which seems to be almost impossible through verb forms in any other nonturkish languages. For example in the following examples sentences 1&2 and 3&4 have the same translation In English although they are different in both meaning and structure. 1. Ali ensha yazirdi. 2. Ali ensha yazirmush. (Ali was writing a composition.) 3. Ali yadmishdi. 4. Ali yadmishimish. (Ali had slept.). The changes in the verb structure in Qashqaie dialect enables its speakers to say that whether the doer of the action remembers the process of doing the action or not. So, it presents a new aspectual opposition as Observed /nonobserved. The research findings reveal many other regularities and linguistic features that can be useful for linguists interested in Turkish in general and for those interested in tense and aspect and also they can be helpful for different pedagogical purposes including teaching and translating.

Keywords: qashqaie dialect, tense, aspect, linguistics, Turkish language

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Authors: Farhina Haque, Chanyeop Park

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The high efficiency, high field, and high power density provided by wide bandgap (WBG) semiconductors and advanced power electronic converter (PEC) topologies enabled the dynamic control of power in medium to high voltage systems. Although WBG semiconductors outperform the conventional Silicon based devices in terms of voltage rating, switching speed, and efficiency, the increased voltage handling properties, high dv/dt, and compact device packaging increase local electric fields, which are the main causes of partial discharge (PD) in the advanced medium and high voltage applications. PD, which occurs actively in voids, triple points, and airgaps, is an inevitable dielectric challenge that causes insulation and device aging. The aging process accelerates over time and eventually leads to the complete failure of the applications. Hence, it is critical to mitigating PD. Sharp edges, airgaps, triple points, and bubbles are common defects that exist in any medium to high voltage device. The defects are created during the manufacturing processes of the devices and are prone to high-electric-field-induced PD due to the low permittivity and low breakdown strength of the gaseous medium filling the defects. A contemporary approach of mitigating PD by neutralizing electric fields in high power density applications is introduced in this study. To neutralize the locally enhanced electric fields that occur around the triple points, airgaps, sharp edges, and bubbles, electrets are developed and incorporated into high voltage applications. Electrets are electric fields emitting dielectric materials that are embedded with electrical charges on the surface and in bulk. In this study, electrets are fabricated by electrically charging polyvinylidene difluoride (PVDF) films based on the widely used triode corona discharge method. To investigate the PD mitigation performance of the fabricated electret films, a series of PD experiments are conducted on both the charged and uncharged PVDF films under square voltage stimuli that represent PWM waveform. In addition to the use of single layer electrets, multiple layers of electrets are also experimented with to mitigate PD caused by higher system voltages. The electret-based approach shows great promise in mitigating PD by neutralizing the local electric field. The results of the PD measurements suggest that the development of an ultimate solution to the decades-long dielectric challenge would be possible with further developments in the fabrication process of electrets.

Keywords: electrets, high power density, partial discharge, triode corona discharge

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Authors: Gholamhossein Hosseini

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Two earliness cotton genotypes I and II, which had been developed by hybridization and backcross methods between sindise-80 as an early maturing gene parent and two other lines i.e. Red leaf and Bulgare-557 as a second parent, are subjected to different environmental conditions. The early maturing genotypes with coded names of I and II were compared with four native cotton cultivars in randomized complete block design (RCBD) with four replications in three ecological regions of Iran from 2016-2017. Two early maturing genotypes along with four native cultivars viz. Varamin, Oltan, Sahel and Arya were planted in Agricultural Research Station of Varamin, Moghan and Kashmar for evaluation. Earliness data were collected for six treatments during two years in the three regions except missing data for the second year of Kashmar. Therefore, missed data were estimated and imputed. For testing the homogeneity of error variances, each experiment at a given location or year is analyzed separately using Hartley and Bartlett’s Chi-square tests and both tests confirmed homogeneity of variance. Combined analysis of variance showed that genotypes I and II were superior in Varamin, Moghan and Kashmar regions. Earliness means and their interaction effects were compared with Duncan’s multiple range tests. Finally combined analysis of variance showed that genotypes I and II were superior in Varamin, Moghan and Kashmar regions. Earliness means and their interaction effects are compared with Duncan’s multiple range tests.

Keywords: cotton, combined, analysis, earliness

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