Green Lighting in Saudi Arabia

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Globalisation Essay Example | Topics and Well Written Essays - 2000 words - 1

Globalisation - Essay Example Consequently, it has made a resounding effect on the picturesque of mankind playing a pivotal role in the social aspect and thereby making drastic changes in the welfare of the civilisation of mankind. Hence, globalisation can be referred as a process of amalgamation through which exchange of world views, products, ideas and different facets of cultures takes place (Lee & Vivarelli, 2006). Based on this context, the paper will be concentrated on explaining the concept of globalisation as an on-going phenomenon by critically discussing the major features of the terminology. Emphasising on the vividness of the term ‘globalisation’, an explanation will also be provided in the discussion henceforth, elaborating the theoretical context of the phenomenon. Concept of Globalisation Globalisation can be referred as one of the major outcomes of the continuous expansion of trade activities and exchanges taking place since ages in the progressively integrated and borderless internat ional economy. There have been extraordinary developments in the trade and exchange related activities, through services, production functions and also through the interaction of currencies in the capital movements (Ojeili & Hayden, 2006). Consequently, globalisation has emerged as one of the revolving strata, opening the doors in the international economy and leading towards the assimilation in relation to markets on a global basis. Although the phenomenon is much debated and illustrated in the economic sphere of the world economy, it has also been playing a crucial role in influencing the social sphere of mankind, interrelating and apparently comparing one culture with another. This also provides a broader scope of harmony and uniformity within the global social atmosphere. Hence, it is on the basis of these rudiments that globalisation has often been regarded as a ‘mega-phenomenon’ rather than a mere change process (Stefanovic, 2008; Houghton & Sheehan, 2000). It is in this context that globalisation process is often argued to facilitate ways for trade liberalisation as well as economic liberalisation heading towards the reduction of conservative and monopolistic trade contributing largely in the development of a liberal world. The description provided by Archibugi & Iammarino (2002) further illustrates that â€Å"the pace of globalisation and that of technological change have in fact been strictly interrelated and, from a long-term perspective, it appears less important to establish which one should be considered responsible for triggering the other rather than to establish that they mutually enforced each other† (pp. 99). Hence, globalisation can also termed as a change driver in today’s context. For instance, globalisation have often been observed to influences changes within organisations, economies, as well as social environment of various cultures facilitating technological changes through resource mobilisation rendering gre ater chances for innovation and development. Another vital dimension of globalisation, which has often been identified in its conceptual framework, is its role to augment better communication within the various participants. Contextually, the major communicators or drivers of globalisation have

Crimes on Campus Essay Example | Topics and Well Written Essays - 1000 words

Crimes on Campus - Essay Example The intent of the bullying person is to gain power over the victim. An individual is said to be bullied when he finds it difficult to protect himself from recurring harmful actions from another person or a group of persons. Bullying students are usually very outgoing and bold without any idea of indignity or remorse; whereas, the bullied ones are already very introverted and hesitant, which makes them prone to bullying. Smith and Sharp assert that school bullying involves â€Å"5-10 per cent of children as being bullied and about 5 per cent of children as bullying others† (5). They state that bullying is generally out of sight of the school authorities, because the bullied students and their peers hesitate in informing their teachers about the bully, and that is why it keeps on going. The National Association of School Psychologists (as cited in Shore 5) estimates that â€Å"160,000 children miss school every day for fear of being bullied†. The description of bullying i s not complete until we describe the aspects of bullying. Bullying can be of various types. Some of these are: Oral bullying: shouting, calling names and spreading rumors about the victim Written bullying: nasty letters and text messages Physical bullying: kicking, hitting, slapping, punching and pushing Isolating the victim from social gatherings Making the victim do things he does not want to do Making the victim feel ashamed of his race, color, religion and language Sexual harassment Cyber bullying: teasing through nasty emails, chat messages and phone calls Bullying can have devastating effects on the bullied student, so much so that he may be forced to commit suicide. He may undergo hypertension, freight, loneliness, anxiety, depression, low self-worth, low grades and suicidal attempts. Glew et al. (1026-1031) found that school bullying resulted in a decline in school attendance, academic outcome, psychosocial adjustment, and psychological health of students. Bullying also crea tes bad impact on the observers of bullying. Since bullying creates an apprehensive environment on campus, students who watch someone being bullied may tend to turn away from their studies feel guilty for not stopping it; or, may even be tempted to participate and support the bullying students. Such students are called the bystanders. Rivers et al. (211-223) conducted a study regarding the mental health of those students who witness school bullying. The participants included 2,002 students aged 12 to 16 belonging to 14 schools in the United Kingdom. The researchers found that â€Å"observing bullying at school predicted risks to mental health over and above that predicted for those students who were directly involved in bullying behavior as either a perpetrator or a victim† (211). The observers are either convinced to take part in bullying or they refrain from involvement or from protecting the victim, all of which are signs of poor mental health. In order to avoid all these negative effects of bullying on campus, I recommend that school authorities should promote interpersonal and helping relationship among its students. Students’

Industry Placement Essay Example | Topics and Well Written Essays - 2000 words

Industry Placement - Essay Example The paper "Industry Placement" analyzes the structure of the international retail company "Toys R Us" and offers some suggestions how to make motivation, reporting, and organizational culture better. The values of the organization make up its culture. I have learned that the company values hard workers that represent the organization's promise of rapid, responsible and reliable service. Based on Fleishman’s interpretation of leadership in which I hold in high regard, modeling this to my staff is one of the best ways I can lead the team in the eyes of myself and Toys R Us. The idea I have of Toys R Us culture was communicated to me through a booklet informing me of what the organization was about, read on my own accord. For Toys R Us to ensure that organizational culture is well known and implemented into the work of management running a program over half a day would be recommended. Interpersonal value compatibility is necessary with the staff because motivation is most effective as an influential leader. It is here that one of many examples of the inter-relatedness of management concepts is displayed. Reward for work through remuneration is the standard return but it is motivation to get the best out of the employee. This can pose quite a challenge for a leader as different types of motivational methods would need to be used for different subordinates. Motivational issues can be found through a number of methods, one of these being reporting. Employee issues can also be found through reporting.

Polymerisation of Light Cured Resin Cements

Polymerisation of Light Cured Resin Cements Discussion (3000-4000 words) Resin-based composite cements are widely and commonly utilised for the cementation of all-ceramic restorations to the prepared tooth structure because clinical studies have identified that using resin cements for this purpose enables the all-ceramic restorations to have an increased fracture resistance in service and thereby improved clinical performance (Kilinc and others). However, this purpose is only fulfilled optimally if the light-cured resin cement is adequately cured to achieve a sufficient degree of polymerisation. In order to initiate the curing reaction, light energy of an appropriate intensity and wavelength must activate and excite a sufficient number of photoinitiators in order to generate an adequate quantity of free radicals. The generated free radicals can then interact with the C=C bonds within the resin monomer and initiate the polymerisation reaction which results in the formation of a polymer (Dias et al, 2008). An adequate cure would consequently determine the s trength of the reinforcement that is achieved via the application of a resin cement to the ceramic specimens. Light transmission Talk about LT at different distances. Increasing the distance decreases both LT and DC. Lack of light can be overcome by increasing light intensity or increasing exposure time In this study, light-cured resin cement was utilised and adequate LT of restorations is even more pivotal for the for the polymerisation of these light cured resin cements because all these cements can utilise is the light that is transmitted through the restoration, or in the case of this study, the ceramic disc (Kilinc and others). The presence of a ceramic disc also restricts the transmission of light to the resin cement as according to Strang et al, a ceramic is capable of absorbing between 40-50% of the curing light (Passos et al, 2013). In this study, light cured resin cement The light transmission in this study was proved to be affected by the thickness and opacity of the ceramic disc as well as the distance from the curing tip. The translucency of a ceramic depends on its crystalline structure, light refractive indexes and the thickness of the ceramic (Kilinc and others). An opaque material may be ideal for aesthetically demanding clinical situations but opacity has been shown to affect light transmission as well as the polymerisation of the resin cement. It is clear from the results in this study that increasing the thickness or opacity of the ceramic disc decreases light penetration through the disc (Duran et al, 2012). A ceramic disc of increasing thickness or opacity would allow lower light energy to be transmitted through it and resultantly, lower LT. An opaque ceramic contains a higher percentage of chroma and this chroma pigment has the ability to absorb light, therefore less light is transmitted through the ceramic and consequently, negatively influencing the polymerisation of the resin cement (Passos et al, 2013). The results also highlighted the fact that the polymerisation was adversely affected with increasing thickness or opacity of ceramic specimens. The presence of a ceramic disc would influence light attenuation and therefore decrease the number of photoinitiators that are activated in the resin cement. The consequence is a lower DC (Filho et al, 2010). Most clinicians implement a curing regime of 400mW/cm2 for 40 seconds and this is thought to be generally enough for adequate polymerisation when applied directly on the ceramic restoration. The ISO recommend a curing light intensity of 300mW/cm2 and the depth of polymerisation should be no greater than 1.5mm. In this study, the curing time used was 30 seconds at an intensity of 800mW/cm2 (Akgungor et al, 2005). In the darker shades and thicker ceramic specimens, (give combos) had reduced light transmission as low as values†¦ therefore, the resin cement cured through these groups of ceramic discs were far from possibly achieving adequate polymerisation (Kilinc et al, 2011). Another option is to use dual-cured resin cements and dentists and clinicians tend to prefer to use dual-cured resin cement systems when cementing all-ceramic restorations because of the important of achieving adequate light transmission through the indirect restoration, which would consequently lead to an optimal degree of conversion of the cement layer, and the chemical reaction of dual-cured resin cements theoretically guarantees a satisfactory polymerisation of the cement as it could compensate for the lack of DC obtained via photo-activated means which would consequently improve clinical performance. The chemical polymerisation of dual cured resin cements is expected to guarantee the cure of the material even in the deeper regions where limited light reaches (Indian journal of dental research). The lower light transmission influences polymer development by primarily decreasing the C=C bond conversion since the polymerisation process is reliant on on the light exposure to both the ceramic but most importantly, the resin cement (Ilday et al, 2012). The lower the degree of light reaching the luting agent, the lower the degree of polymerisation and consequently, the lower the success and longevity of the resin-strengthening mechanism (Pazin et al, 2008). Light transmission through the ceramic and to the resin cement is vital because if the ceramic restoration/disc prevents polymerisation light from reaching the resin cement layer, causing inadequate polymerisation of the cement layer. This consequently affects the strength of the restoration and the risk of debonding is higher in poorly polymerised cement (Akgungor et al, 2005). During the process of light activation, the light passing through the ceramic is absorbed and scattered. Thereby, the light irradiance produced by the light source is attenuated and its effectiveness is reduced as the ceramic thickness increases (Filho et al, 2010). This was proven in a study by Meng et al, in which it was shown that a light intensity of 800mW/cm2 decreased significantly to 160mW/cm2 after light transmission through a 2mm thick ceramic specimen (Filho et al, 2010). The greater the LT through a ceramic material, the greater the irradiance reaching the resin cement surfaces and accordingly the greater the DC and mechanical properties (Pick et al, 2010). The light transmission through a ceramic restoration may affect the degree of polymerization of resin cements, because the amount of light that reaches the cement layer is decreased.10In general, the factors affecting light transmission through a ceramic material include the thickness and shade of the ceramic material, its microstructure, and the presence of defects and porosities. However, the thickness of indirect materials interposed during photo-activation is a key factor for light attenuation, and polymerization generally decreases as thickness increases.12 The physical and mechanical properties of resin cements may be affected by the thickness and microstructure of ceramic restorations. It is important to emphasize that light-cured resin cements should receive an adequate energy density to reach good polymerization and mechanical properties. Furthermore, only effective photo-activation may ensure clinically acceptable hardness levels of dual-cured resin cements, mainly in criti cal areas. Considering these issues, further studies are needed to find a way to compensate light attenuation aggravated by the interposition of indirect restorative materials. http://www.duhs.edu.pk/download/jduhs-vol.7-issue-2/9.pdf DC Increasing the distance, thickness or opacity of ceramic/resin cement layer would mean that the top few millimetres of the resin cement would adequately polymerise and the remaining material would poorly polymerise due to lack of light (Silva et al, 2009). Insufficient curing also enhances the solubility of the cement which is the common cause of debonding of the restoration (Dias et al, 2008). As the properties of the resin cements are directly related to the degree of polymerisation, the resin cement used for cementation was measured using FTIR. Favourable resin cement polymerisation is vital in order to obtain optimal properties of the cement in order to prolong the longevity and clinical performance of the overlying all-ceramic restoration (Ilday et al, 2012). Various studies have stated the importance of a high monomer-to-polymer conversion with a highly cross-linked polymeric network in order to obtain a clinically successful resin-based restoration. The presence of an increased amount of monomers decreases both DC and mechanical properties and the fracture resistance of the restoration (Francescantonio et al, 2013). The DC% of the resin cement was decreased under the darkest, thickest ceramic combination than under the thinnest, lightest ceramic. The clinical performance of both the resin cement and the ceramic restoration depends on many important factors, with one of these being the degree of polymerisation (journal of the Serbian chemical society). One way of assessing the DC of the resin cements is through the use of Fourier transform infrared spectroscopy (FTIR) which detects the C=C stretching vibrations directly before and after curing of the resin cement material (Obradovic et al, 2011). Several factors have been shown to influence the polymerisation of resin-based cements such as the thickness of the resin cement layer, the intensity of the light source as well as the type of light source used, the distance from the curing tip and the duration of curing. The composition of the resin-cement can also affect the rate of polymerisation via factors like the polymer matrix, the filler particles and the coupling between matrix and filler (Obradovic et al, 2011). After a certain period of time, the DC graph appears to straighten off with no increase. This limited conversion is due to limited mobility of the radical chain ends and this limits the conversion of the pendant methacrylate groups from monomer to polymer (Obradovic et al, 2011). During the process of light activation, multiple growth centres are produced and the matrix transforms from a liquid to a viscous phase via the production of a polymer network from a monomer, i.e. the process of gelation. However, subsequently, the polymer network is highly cross-linked as most of the monomer is converted to polymer which results in the link between the monomers and the oligomers with the network being restricted due to limited diffusion (Filho et al, 2010). With light activation, there is a production of free radicals via the excitation of photoinitiators which enables the initiation step to occur instantaneously. As the propagation phase proceeds, the resin cement changes from a liquid to a viscous gel state, thereby making it increasingly difficult for monomers to diffuse to the polymeric growth centres. As a result, as the polymerisation reaction proceeds, less monomer is converted to polymer (Mendes et al, 2010). The rate of polymerisation reduces as the reaction proceeds due to the formation of fewer polymer growth centres. This promotes the formation of loosely cross-linked polymers and poorer mechanical properties (Silva et al, 2009). Adequate polymerisation of the resin cement is crucial for stability, optimal mechanical properties and the clinical performance of the indirect all-ceramic restoration. Furthermore, a greater degree of polymerisation would result in a greater bond between the resin-cement and the ceramic and consequently, maximum bond strength (Ilday et al, 2012). Along with using thinner or less opaque ceramic and resin cement layers, the cure depth of the resin cement, the degree of conversion and consequently the strength of the restoration can be increased by longer light exposure times or increasing the light intensity (Ilday et al, 2012). The latter two factors were not evaluated in this study. Insufficient polymerisation commonly causes early failure of the cemented all-ceramic restoration (Duran et al, 2012). BFS Flexural strength were found to show a relationship with conversion of double bonds with the resin cement (Ozturk et al, 2005). Ceramic specimens luted with a resin luting agent exhibited greater flexural strengths than the specimens without any form of luting agent (Pagniano et al, 2005). Look at pagniano journal for more info- if space left. The discs were left for 24 hours prior to BFS testing because the cement undergoes polymerisation for 24 hours after curing and if BFS was tested straight after curing, then the cement would not have reached the maximum polymerisation possible and therefore the risk of debonding and poor flexural strength is greater (Akgungor et al, 2005). The magnitude of strengthening is reliant on on the flexural modulus of the resin cement. This can also be known as the modulus of elasticity. (value of resin cement according to dr Addison journal). The modulus, in other studies, has been identified to be between 7 and 12 GPa. The elastic modulus of the cement is vital to study because it is related to how effectively stress can be transmitted between the all-ceramic restoration and the tooth structure. Moreover, it provides an indication as to how well the cement can resist elastic deformation which ultimate would endanger the integrity of the bonded interface between the ceramic and cement. Ideally, the resin cement should have an elastic modulus that is between that of dentine and the ceramic restorative material (Braga et al, 2002). Flexural strength of brittle materials is likely to be more affected by surface defects or imperfections such as porosity, cracks and other related flaws. Specimen failure is thought to initiate at the bottom surface of the specimen and all ceramic specimens were placed with the non-irradiated surface facing towards the load application and therefore a lower DC would lead to a reduced flexural strength (Pick et al, 2010). From BFS testing, it was evident that a decrease in BFS generated at the resin-ceramic interface when testing the ceramic specimen (A3.5 at 1.40mm) with the lowest DC. Resin coating significantly increased the mean BFS of the greatest conversion system but not as significantly in the other two groups of ceramic specimens tested. It should be noted that the system with the greatest DC had the greatest change in BFS which highlights the importance of DC on the magnitude of resin-reinforcement that is achieved (Fleming et al, 2012). Despite the resin-reinforcement, it is suggested by Yesil that failure still occurs and the mode of failure is caused by surface flaws or flaws within the ceramic material, the adhesive layer, or the bonded cement and flaws in the interface (Yesil, 2009). Furthermore, in a different study carried out by Thompson et al, the results demonstrated that when clinically failed glass-ceramic restorations were analysed, the majority of these restorations failed because of fractures and most of the fractures initiated from flaws and stresses originating from the adhesive resin cement interface and not from the restoration contact surface (Yenisey et al, 2009). Clinically, the thickness and opacity of the ceramic restoration acts as a barrier to light penetrating the methacrylate resin-based composite cements. Therefore, the durability of the bond produced between the ceramic restoration and the resin cement as well as the interface between the cement and the surrounding tooth structure will be compromised. For resin-based composites, a maximum value of DC is ideally wanted in which there is complete conversion of the monomer double bonds to network contributory single bonds. However, the conversion is normally between 45-70% because vitrification stops the reactions by inhibiting diffusion (Isgro et al, 2011). The strength values may be different due to the absence of polishing in the ceramic specimens that were tested for BFS. The discs used in LT testing were polished whereas the ceramic discs tested in BFS were not polished. Instead, the internal fit surfaces of the dental ceramics were roughened to promote adhesion. The strength values obtained may have been affected by the absence of polishing of dental ceramic specimens prior to mechanical testing. (see Isgro et al, 2011) for more info. Give values of % increase between cemented and uncemented samples and the mean values. Look at Pagniano et al, 2005 for information on how the interaction between cement and ceramic affects BFS. Add if word count available. Future work Look at effect with different light output- look at Duran et al, 2012 journal. If space left, look at Pazin et al journal for info on degree of cross-linking. Look at SEM images Look at Molin et al, 2006 and Isgro et al, 2011 for info on contraction stresses for BFS In conclusion, adequate polymerisation is desirable to reduce problems associated with post-operative sensitivity, microleakage, risk of recurrent caries, discolouration, in addition to decreased mechanical, chemical and physical properties of the resin cement. Furthermore, it will compromise the clinical success and longevity of the restoration. Sufficient DC would also improve the biocompatibility of the restoration and most importantly, the resin cement layer by reducing the number of residual monomers that are leached into the oral environment (Kim et al, 2009; Yan et al, 2010; Braga et al, 2002).

Eye movements are a reflection of cognitive processes Essay -- Psychol

Introduction The mind is an intriguing element of the human life not only because of its complexity and capability but mostly because of its opacity. How does psychology begin to understand something so obscure and complex? Evidently, by observing and measuring the product of the cognitive processes that occurs through an interaction between the external and internal world. The term ‘cognitive processes’ is a rather collective term referring to a range of mental processes such as perceiving, thinking, speaking, acting, planning and imagining (Ward, 2006). The processes themselves are immensely difficult to measure directly, if possible at all. However, one may gain insight into these mental processes through observing the covert products, such as haemodynamic and electrophysiological changes and the overt products, such as behaviour, accuracy, response times and eye movements. The scope of this essay is to review the evidence that demonstrates exactly how eye movements reflect cognitive processes. Due to the vastness of the topic, this essay will focus on only one of the aforementioned cognitive processes. There has been much attention and extensive literature and reviews regarding eye movements as a tool for understanding the processes of reading, visual perception, visual search and attention (e.g., Rayner, 1998; Liversedge and Findlay, 2 000; Schutz, Braun and Gegenfurtner, 2011). All the mentioned research fields involve measuring eye movements while view some form of visual stimulus, this dissertation will explore a more aberrant field, evidence will be based on literature relating to eye movements when sensory visual input is absent, during visual mental imagery. While reviewing the literature basic themes relating eye m... ...nformation processing: 20 years of research. Psychological Bulletin, 124, 372-422. Schutz, A.C., Braun, D.I., & Gegenfurtner, K.R. (2011). Eye movements and perception: A selective review. Journal of Vision, 5, 1-30. Shallice,T. (1988). From neuropsychology to mental structure. New York: Cambridge University Press. Sima, J.F., Lindner, M., Schultheis, H., & Barkowsky, T. (2010). Eye movements reflect reasoning with mental images but not with mental models in orientation knowledge tasks. Spatial Cognition, 10, 248-261. Spivey, M.J., & Geng, J.J. (2001). Oculomotor mechanisms activated by imagery and memory: eye movements to absent objects. Psychological Research, 65, 235-241. Ward, J. (2006). The students guide to cognitive neuroscience. New York: Psychology Press. Watson, J.B. (1913). Psychology as the behaviourist views it. Psychological Review, 20, 158-177.