Reflect on a challenge you overcame through persistence (650 words) Essay

Reflect on a challenge you overcame through persistence (650 words) - Essay Example I read the speeches of Socrates when I entered my tenth grade. It was then that i realized that I wanted to attain a speech ability like his through which i could persuade people as to what life really is about. In the tenth grade i tried competing in the debates organized by my school but i was not encouraged a bit by my parents or teachers. When i gave the auditions of my debate for the first time in school not a single stone was unturned in humiliating me by my class mates. It was then that i was quite discouraged and went into isolation for a few days to think as to if i could achieve my goal or not. However i did not lose hope and worked on my abilities to deliver speech. My aim was to participate in the debate competition as a leading participant but this aim was laughed upon by many of my class mates. In order to grasp better skills i had to sort out certain things which i lacked when delivering speeches. I suffered from the problem of stage fear and i had to cut off this prob lem first in order to deliver the speeches. To rectify this problem i started participating in activities which had audiences viewing it. The first option was of selecting different sports and participating in different activities so i could get strong in front of the audience. This greatly helped me in the field of debates as i learned to act in certain situations. After that my very next aim was to work on my debating skills. I began reading books and increased my vocabulary so i could write a better speech which would attract the audience. I learned the basics of debating through different lessons and i was successfully able to craft speeches. I delivered my speech in front of my friends and some of them praised it. This gave a boost to me so that i could compete in the next competition. I also got the encouragement of my parents and teachers after i rehearsed in front of them. I polished my skills of debating since i passed my tenth grade and was able to deliver in my next try. It was in high school that i tried for competing in debating again and this time the try was not wasted. I received a better appreciation from the crowd but still could not make up to the final participants. I erased my stage fear and learned to act in the situations of debates. It was here that the changing point of life had arrived. The teachers realized the potential in me and gave me a chance again in the last year of my high school. I learned skills from them and delivered well in the auditions. I was then qualified finally for the participants sent through my school. Although this was my first exposure to debates nationally i learned a lot from the event. I did not get to win from the event but my goal of being a debater was fulfilled. It was then that i made a platform for me to be a debater. After I passed my high school i participated in events which were outside the territory of my school and learned a lot. I have since become a debater with the right potential. My aim of becoming a debater only became successful after I went through a lot in my life. Persistence as said by Edison was the major source of success in my life. I have learned a lot through my experience and can now successfully achieve many of the aims that i had in

Social entrepreneurship Essay Example | Topics and Well Written Essays - 1000 words

Social entrepreneurship - Essay Example While this aspect may seem obvious, the distinction interests me deeply because of social entrepreneurship’s potential to produce breakthrough outputs that could solve the perennial social problems such as income disparity, monopolies and so on. We should remember that we have been under some economic systems but our world is still confronted with issues such poverty, exploitation and so forth. In the course of my studies and research in this field, I have come across a lot of business models that sought to define what constitutes business and its purpose. There has been some degree of confusion for me since it seemed logical and reasonable to follow the popular economic theories, such as those of Milton Friedman’s which place profit as the main objective of a business’ existence. This was where things got interesting because the concept of the social entrepreneur disproved some widely accepted notions, say, in terms of the stakeholders in an enterprise. For the traditional business people, the sole stakeholder in a business organization is the stockholder or the owner of the capital and that the management is working for his benefit. In social entrepreneurship, the stakeholder is not only the entrepreneur but they include the community, the employees, their clients and all the participants in the organization and its operation. The attributes cited by William Drayton, which differentiates an entrepreneur from the social entrepreneur further underscores my point: â€Å"Social entrepreneurs have the same core temperament as their industry-creating, business entrepreneur peers but instead, use their talents to solve social problems.† (Drayton, 2002) If this concept would be refined into a successful business model and integrated in the mainstream, then there is a chance of a radical positive change not just in business but in the society as well. In line with the previously mentioned â€Å"pearl† the second important point that I would like to discuss

Anomalous Resistance Behavior in Bilayer Graphene

Anomalous Resistance Behavior in Bilayer Graphene Observation of Anomalous Resistance Behavior in Bilayer Graphene Yanping Liu 1,2, Wen Siang Lew 2,*and Zongwen Liu 3,* Abstract Our measurement results have shown that bilayer graphene exhibits an unexpected sharp transition of the resistance value in the temperature region 200~250K. We argue that this behavior originates from the interlayer ripple scattering effect between the top and bottom ripple graphene layer. The inter-scattering can mimic the Coulomb scattering, but is strongly dependent on temperature. The observed behavior is consistent with the theoretical prediction that charged impurities are the dominant scatters in bilayer graphene. The resistance increase with increasing perpendicular magnetic field strongly supports the postulate that magnetic field induces an excitonic gap in bilayer graphene. Our results reveal that the relative change of resistance induced by magnetic field in the bilayer graphene shows an anomalous thermally activated property. ______________________________________ Introduction: The electronic properties of monolayer graphene have been extensively studied due to its intriguing energy band structure with linear dispersion around the Dirac point and chirality exhibiting Berry phase of [1]. There is a zero-energy Landau level (LL) with four-fold degeneracy due to interactions between electron spins and valleys in the magnetic field [2-4]. Recently, bilayer graphene became a subject of intense research due to the low energy Hamiltonian of chiral quasiparticles and a Berry phase of [5-8]. It has a double-degeneracy zero-energy Landau level that incorporates two different orbital states with the same energy under an external magnetic field. The bilayer graphene with a Bernal (A-B) configuration loses some features of monolayer graphene and has a unique band structure where the conduction and valence bands are in contact with a nearly quadratic dispersion [5]. In bilayer graphene, a parabolic band structure ( ) with an effective mass m*=0.037, has been calculated by using the interlayer coupling model [9-14]. What makes bilayer graphene an interesting material for study is that the interlayer potential asymmetry can be controlled by an electric field, thus opening an energy gap between the conduction and valence bands [16-18]. Various applications for bilayer graphene are possible due to the fact that its band gap can be modulated by using an external out-of-plane electric field and chemical doping. There is intensive research on bilayer graphene under the application of a perpendicular electric field, however, experimental reports on magnetic transport properties of bilayer graphene are not as well-studied. Recent theoretical work reports on excitonic condensation and quantum Hall ferromagnetism in bilayer graphene [22]. There are interesting features in bilayer graphene due to its extra twofold orbital degeneracy in the LL spectrum, which results in an eightfold -degenerate LL at zero energy. The scattering mechanism of graphene is current ly a subject of intense research and debate. The problem of magneto-transport properties in the presence of Coulomb impurities is still an open research problem. Our understanding of the nature of the disorder and how the mesoscopic ripple effect affects the transport properties still need improvement; hence, a better understanding on the general electric and magnetic transport properties of bilayer graphene is necessary. In this paper, we have systematically investigated the charge transport properties in bilayer graphene as a function of temperature, magnetic field, and electric field. Our measurement results have shown that bilayer graphene exhibits a semi-metallic R-T property and an unexpected sharp transition of the resistance value in the temperature region 200~250K. The longitudinal resistance decreases with increasing temperature and electric field, a behavior that is markedly different from the experimental reports of monolayer graphene. Our results reveal that the energy gap in the bilayer graphene shows an anomalous thermally activated property and increases with. We have shown that this phenomenon originates from a tuneable band structure behavior that can be controlled by a magnetic field, a property that had never previously been observed in bilayer graphene. It has been shown that Raman spectroscopy is a reliable, non-destructive tool for identifying the number of graphene layers and it can be done through the 2D-band deconvolution procedure [23-25]. The Raman spectra of our graphene structure were measured at room temperature using a WITEC CRM200 instrument at 532 nm excitation wavelength in the backscattering configuration [26-28]. Fig.1a shows the characteristic Raman spectrum with a clearly distinguishable G peak and 2D band. The two most intense features are the G peak and the 2D band which is sensitive to the number of layers of graphene. The position of the G peak and the shape of the 2D band confirm the number of layers of graphene. Additionally, the number of layers of graphene can be easily distinguished from the full width half maximum of the 2D band, as its mode changes from a narrow and symmetric feature for monolayer graphene to an asymmetric distribution on the high-energy side for bilayer graphene [27]. The 2D band inset in Fig.1a shows that the Raman spectrum of bilayer graphene is red-shifted and broadened with respect to that of the monolayer graphene. Fig. 1b shows the four terminal resistance as a function of carrier-density n, and the sample shows a pronounced peak at density . Note that the sharp peak in resistance at low n is enhanced by the opening of the small energy gap owing to disorder-induced differences in carrier density between the top and the bottom layers of the flake. We have characterized the current (I)-voltage (V) characteristics of the bilayer graphene via four-terminal measurement, at different temperatures and magnetic fields. Shown in Fig. 2a are the I-V curves for bilayer graphene under the application of various magnetic fields at three different temperatures: 2 K, 200 K and 340 K. The magnetic field is applied in the perpendicular direction to the plane of the graphene. For all the temperatures and magnetic field strengths, the bilayer graphene exhibits a linear I-V curve. This implies that the graphene layer is ohmic in nature. We observed that for a fixed magnetic field, the I-V curve displays a larger gradient at higher temperature than at lower temperature. Interestingly, the gradient of the I-V curve decreases with increasing magnetic field. In our structure, the gradient of the curve corresponds to the conductivity of the graphene layer. Such temperature and magnetic field dependent behaviour of conductivity is characteristic of an intrinsic semiconductor. The decrease in the conductivity of the bilayer graphene with increasing magnetic field is attributed to the excitonic energy gap induced by the magnetic field. This conductivity dependence on the magnetic field suggests that the resistance () of graphene is a qualitative fingerprint of its band gap. In the absence of a magnetic field, the band structure of the bilayer graphene at the Dirac valley has a parabolic dispersion relation. When a magnetic field is present, the band structure is changed to a split Landau level structure [19-21]. Fig. 2(b) is an illustration of the bilayer bandgap and Landau level splitting under the influence of a magnetic field. Inset shows an optical image of the bilayer graphene with the metal contact electrodes. In Fig.2(c) we plot the resistance of the bilayer graphene, as extracted from the I-V curve, as a function of magnetic field for three different temperatures. As the magnetic field was increased in a step of 4T, the resistance increase for each step was different, resulting in a non-linear relationship between the resistance and magnetic field. Interestingly, the observed non-line relationship is markedly different from Zeeman spin-splitting theoretical model with the line relationship, where gap with a free-electron g-factor g=2, where is the Bohr magneton. This potentially indicates sublattice symmetry breaking and gap formation due to many-body correction in this LL [32-34]. This is further confirmation that magnetic field opens an excitonic gap in the bilayer graphene. The temperature dependence of monolayer graphene resistance is mainly attributed to the different scattering mechanisms: Coulomb scattering [35-36], short range scattering [37], and phonon scattering [38-39]. However, the temperature dependence of bilayer graphene resistance has not been established yet. Shown in Fig.3a are the temperature dependence of the resistance of the bilayer graphene under the application of a magnetic field 0T and 12T, respectively. The results show that the resistance of the bilayer graphene drops following non-metallic behaviour as temperature increases from 2K to 340 K. This implies that the bilayer graphene resistors have intrinsic semiconductor properties as mentioned earlier. This can be explained by the decrease in Coulomb scattering with temperature for bilayer graphene due to its parabolic band structure. For B=12T, a similar trend as B=0T is obtained in Fig 3a, where the resistance decreases with increasing temperature. However, the resistance for the entire temperature range is much larger than for B=0T. This indicates that the magnetic field opens an excitonic gap in the bilayer graphene that is thermally activated due to the Coulomb interaction ion-driven electronic instabilities [20, 31]. Ripples are a common feature of cleaved graphene because it is never atomically flat, as it is placed on a substrate such as SiO2 in the term of nanometre-scale deformations or ripples [40-42]. Despite the magnitude of the ripples being quite small, it is still believed to be responsible for the unusual transport behaviour of graphene, also susceptible to adsorbed impurities, defects and the roughness of the underlying substrate [40-43]. On the other hand, it has been shown that suspended graphene films are corrugated on a mesoscopic scale, with out-of-plane deformations up to 1 nm [44-45]. The deformation is a typically smaller than the Fermi wavelengthand these ripples induce predominantly short-range scattering. The observed height variation shows that the surface roughness beyond the atomic-level is intrinsically present in bilayer graphene. Hence, one of the interesting features of corrugation of graphene is that it offers a new experimental opportunity to study how the corrugat ion-induced scattering impacts the transport properties of graphene. It is important to mention that there is a strange sharp threshold like decrease in resistance observed above 200K. The strong temperature dependence is inconsistent with scattering by acoustic phonons. One possible explanation is that the flexural phonons confined within ripples between the top and bottom layer causes the scattering. The presence of the ripple effect exhibits local out-of-plane ripples [44]. Theoretical calculations[41,46] show that the scattering rates for interripple flexural phonons with respect to two-phonon scattering process as, where is the flexural-phonon frequency, the derivative of the nearest-neighbour hopping integral with respect to deformation, a the lattice constant, , and the mass of carbon atom [46]. For low temperatures T () , few flexural modes can be excited inside ripples (). The conductivity of the surface roughness model at the limit at low temperature is[45-46]. As the t emperature increases and typical wavelengths become shorter, short-range scattering excites the flexural phonons. For the high temperature limit, based on the above expression, we can estimate that , which yields ~100 to 1000 at T=300K. The model of quenched-ripple disorder [46] suggested that the electron scattering of the static ripples quenched from the flexural phonon disorder can mimic Coulomb scattering when at room temperature. One should also note that the model predicts stronger temperature dependence (above a certain quenching temperature of about 100K) which is close to our experimental result at about 200K. However, the ripple effect normally leads to a rapid increase in the R-T curve rather than the sudden decrease in R-T as observed for our bilayer graphene. In the absence of a theory to explain the stronger temperature dependence behaviour, we propose that the behaviour is consistent with the ripple effect interlayer scattering instead of interlayer scattering. Fig. 3b shows the schematically illustration of scattering mechanisms in bilayer graphene. For a bilayer graphene, the interlayer scattering between the top and bottom ripple graphene layer is similar to coulomb scattering with stronger dependence on temperature. The rapid decrease in R-T above 200K can be attributed to the transition between the low- and high-T limits in the interlayer ripple effect scattering. On the other hand, it was suggested that the observed strong T dependence could be explained by thermally excited surface polar phonons of the SiO2 substrate [35-38]. The SiO2 optical phonons at the substrate-graphene interface induce an electric field which couples to the carriers in graphene due to it modulating the polarizability [38-39]. However, Coulomb scattering is dominant for bilayer graphene and the substrate surface polar phonon induced field is to some extent screened by the additional graphene layers [39]. Recently it has been shown that the substrate dielectric constant plays an important role in scattering in graphene. Theoretical predictions show that for dielectric constant , Coulomb scattering dominates, while for dielectric constant , short-range scattering dominates, as Coulomb scattering is more strongly screened for materials with a larger dielectric constant. In fact, our observed behaviour is consistent with the theory suggesting that scattering from charged impurities is dominant in graphene. We introduce a relaxation-time approximation and treat the unscreened Coulomb potential as [1,5] where Q is the charge of impurities. Based on the Boltzmann transport theory, we can obtain the bilayer graphene resistivity with massless Dirac-fermions (MDF) at low energies as. For high temperature , , we can obtain the bilayer graphene resistivity as[47], where is the density of impurities per unit volume, is the permittivity of the semiconductor, and is the charge state of the impurity. This shows that the resistance of bilayer graphene limited by Coulomb scattering increases as increases and decreases with increasing temperature. Considering the above analysis, we deduce that the temperature dependence of resistance in bilayer graphene is mainly determined by Coulomb scattering. The short-range scattering is independent of temperature for bilayer graphene, as the density-of-states, the matrix element and the screening function are all energy independent. As a result of the parab olic band structure of bilayer graphene, the energy averaging of the Coulomb scattering time can give rise to the resistivity decreasing proportionality to temperature : . Based on the above discussion, we fit the measured resistance in Fig.3a by using the following model for bilayer graphene:, where and are the resistance due to the Coulomb and short-range scatterings, respectively. Fig.3b shows the relative resistance change under the biased and unbiased magnetic field as a function of temperature, and the dotted line is the fit following the equation , where is the energy gap. The opening of the energy gap due to a potential difference between the two layers and Coulomb interactions could be a cause for this. These considerations explain qualitatively why the resistance of bilayer graphene decreases with increasing temperature. Note that the relative resistance change is a strong function of temperature. At temperatures of 2Kà ¯Ã¢â€š ¬Ã‚ ­180K and 220Kà ¯Ã¢â€š ¬Ã‚ ­250K, the relative resistance strongly increases as temperature increases, indicating that an energy gap forms due to many-body correction in Landau Level. When the temperature incr eases to T >250K, the relative resistance is roughly independent of the increasing temperature; this indicates that the energy gap is mostly stable at high temperatures. On the other hand, with the temperature increase from 180K to 220K, the relative resistance dependence of temperature shows a sharp decrease, which indicates that the energy gap shows an anomalous thermally activated behaviour as a function of temperature. For zero gate voltage (i.e., neutrality point), we measured changes in longitudinal resistance as a function of applied perpendicular field B. Fig. 4a shows the four-terminal longitudinal resistance of bilayer graphene as a function of magnetic field at T= 2K at the charge-neutrality point. We have plotted the resistance per square, because it is independent of a size effect of the sample. As seen from Fig. 4a, the resistance increases nonlinearly with the magnetic field strength followed by a plateau-like phase. One should note that the plateau-like phase in Fig. 4b disappears at higher temperatures. One possible explanation is the augmented sublattice spin-splitting due to the high surface-impurity concentration of the graphene layer [18]. The origin of the nonlinear magnetoresistance increment behaviour is the splitting of Landau level that gives rise to a bandgap opening at the zero energy level [32-34]. In our measurements, we fit our results to an analytical approximation for the non-linear resistance , where is the Boltzmann constant. We found that our results are in good agreement with this equation. These considerations explain qualitatively why the nonlinear resistance increases with the magnetic field. Fig. 5 shows the resistance of bilayer graphene as a function of electric field (E) under different magnetic fields. The dependent characteristics are symmetric due to the chirality of graphene electrons when an applied electric field changes from E to E. The normalized resistance curve describes the response under the applied magnetic field in the range of B=0T to B=12T and the temperatures of 2-340K. The results demonstrate that when the magnetic field increases from 0T to 12T at low temperatures (2à ¯Ã¢â€š ¬Ã‚ ­200K) and low electric field (E), the resistance of bilayer graphene drops significantly. The larger slump in the resistance at lower temperature T=2K and low electric field as the increasing of electric field are due to Coulomb scattering by impurities, which is a strong function of temperature. On the other hand, at high temperatures (T >200K) and electric fields (E>0.01 ), the resistance of bilayer graphene show a linear decrease. This can be explained by the scatteri ng from thermally excited surface polar phonons of the substrate being screened by the additional top graphene layers [39]. This further confirms that at high temperatures, the scattering induced by the electric field on the substrate surface polar phonons is significantly screened between top and bottom layers in bilayer graphene. In our experiment, temperature and magnetic field dependence of resistance of bilayer graphene was investigated. Intrinsic semiconductor behaviour at the range of temperature is 2K-340K was observed. The strange sharp threshold-like decrease in resistance around 200K is unexpected, and we attribute it to the presence of mesoscopic ripples between the top and bottom layer. Our results reveal that the energy gap in the bilayer graphene is thermally dependent. This potentially indicates the sublattice symmetry breaking and an energy gap formation due to Landau Level splits. The obtained results are important for the better understanding of magnetic field induced high resistance and provide indications of a theoretically predicted magnetic field induced excitonic gap. Acknowledgements Y. L would like to thank Prof. Wang and Prof. Yao for his useful discussions. This work was supported in part by the NRF-CRP program (Multifunctional Spintronic Materials and Devices) and the Agency for Science, Technology and Research (A*STAR) SERC grant (082 101 0015). The authors thank Sun Li and Li Yuanqing for their assistance in experimental measurements. Experimental section The bilayer graphene samples for this study were prepared using mechanical exfoliation techniques [2] from the bulk highly oriented pyrolitic graphite (grade ZYA, SPI Supplies) and transferred onto the surface of a lightly doped silicon substrate covered with a 300-nm thick layer of thermally grown , The doped silicon substrate and were used as back-gate and gate dielectric, respectively. Graphene electrical electrodes were patterned using photolithography techniques. A pair of ohmic Cr/Au (5nm/100nm) contacts were deposited via thermal evaporation at a background pressure of 10à ¯Ã¢â€š ¬Ã‚ ­7 mbar and subsequently lifted off in warm acetone. Electronic transport measurements have been carried out on multiple samples, using PPMS (Quantum Design) with a fixed excitation current of 10 . Electrical measurements were performed in the temperature range 2K ~340K and a magnetic field up to 12T was applied. In order to enhance electrical transport, the sample was cleaned in situ by the mag netic and electric field. Four-terminal electrical measurements were used for transport characterization. References          Geim, A. K.; Novoselov, K. S, The rise of graphene. Nature Materials 2007, 6, 183-91. Novoselov, K. S.; Geim, A. K.; Morozov, S. V.; Jiang, D.; Zhang, Y.; Dubonos, S. V.; Grigorieva, I. V.; Firsov, A. A., Electric field effect in atomically thin carbon films. Science 2004, 306, 666-9. Novoselov, K. S.; Geim, A. K.; Morozov, S. V.; Jiang, D.; Katsnelson, M. I.; Grigorieva, I. M.; Dubonos, S. V.; Firsov, A. A., Two-dimensional gas of massless Dirac fermions in graphene. Nature 2005, 438 , 197-200. Novoselov, K. S.; Jiang, Z.; Zhang, Y.; Morozov, S. V.; Stormer, H. L.; Zeitler, U.; Maan, J. C.; Boebinger, G. S.; Kim, P.; Geim, A. K., Room-Temperature Quantum Hall Effect in Graphene. Science 2007, 1137201. Peres, N. M. R., The electronic properties of graphene and its bilayer. 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S., Determination of the gate-tunable band gap and tight-binding parameters in bilayer graphene using infrared spectroscopy. Physical Review B 2009, 80, 165406. Morozov, S. V.; Novoselov, K. S.; Katsnelson, M. I.; Schedin, F.; Elias, D. C.; Jaszczak, J. A.; Geim, A. K., Giant intrinsic carrier mobilities in graphene and its bilayer. Physical Review Letters 2008, 100 (1). Barlas, Y; Cote, R.; Nomura, K.; MacDonald, A. H., Inter-Landau-level cyclotron resonance in bilayer graphene. Physical Review Letters 2008, 101 (9). KrsticÃÅ' , V; Obergfell, D.; Hansel, S.; Rikken, G. L. J. A.; Blokland, J. H.; Ferreira, M. S.; Roth, S., Grapheneà ¢Ã‹â€ Ã¢â‚¬â„¢Metal Interface: Two-Terminal Resistance of Low-Mobility Graphene in High Magnetic Fields. Nano Letters 2008, 8 (6), 1700-1703. Bisti, V. E.; Kirova, N. N., Charge Density Excitations in Bilayer Graphene in High Magnetic Field. Jetp Lett. 2009, 90 (2), 120-123. Nomura, K; MacDonald, A. H. Physical Review Letters2006, 96, (25), 256602. 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X., Graphene thickness determination using reflection and contrast spectroscopy. Nano Letters 2007, 7, 2758-63. Zhang, C. H.; Joglekar, Y. N. Physical Review B 2008, 77, (23), 233405. Ezawa, M., Intrinsic Zeeman effect in graphene. Journal of the Physical Society of Japan 2007, 76 (9). Barlas, Y.; Cà ´tà ©, R.; Nomura, K.; MacDonald, A. H. Physical Review Letters

Destroying Your Health By Smoking Cigarettes :: Argumentative Persuasive Example Essays

Destroying Your Health By Smoking Cigarettes If you really want to ruin your health then smoking cigarettes is one of the best ways I know how to do it. Smoking cigarettes cause lung cancer, emphysema, and the one thing that most people notice right off hand is bad breath. If you are into destroying your health, I want you to follow these step so that you can be on your way to an unhappy and unhealthy life, number one buy the cigarettes, number two smoke them, and number three this one is really important never ever quit smoking. I have found that most people who want to destroy themselves quickly will smoke a no filtered brand of cigarettes, so let say you picked out the brand Pallmall-Reds. I understand these are one of the strongest brands of cigarettes you can buy. Yes, there are plenty of other brands of cigarettes out there but why bother going threw all that money to pick the right one when you can take my word on it? These are really strong cigarettes. How do I know, because take one out and look at it, you will notice that there is no filter on the end of it. Due to no filter you will get none of the toxins filtered Without filtering out some of the toxins you will destroy yourself quicker; that is the goal we are seeking, is it not? Lets take out one of our friends (we will call them that to be funny) and look at it. It is about five to six inches in length, maybe a half inch wide with little brown things that look somewhat like coffee grounds inside a thin white paper cylinder. Smell it, a significant number of people actually enjoy the way tobacco products smell, but they will not smoke them. I myself find that ominously odd. Now smoking the cigarette is very important. If you do not smoke it you will not reach your goal to destroy your health. So let us begin with the lighting of the cigarette. Place the cigarette in your mouth, just the tip of it. Do not bother with looking to put the filtered end in your mouth, because if you remember there is no filter on is brand of cigarette. After you have placed our friend in your mouth you will need to tilt your head. Tilting is something most people do when â€Å"lighting up," this process is what majority of people do. Now when you tilt your head it really does not make a difference

Alternative Medicine And Placebo Effect Health And Social Care Essay

Alternate medical specialty is going more widely used, particularly in the United States wellness attention system and it is suggested that more than 80 % of the universe ‘s population usage complementary and alternate medical specialties ( CAMs ) ( Mainardi, Kapoor & A ; Bielory, 2009 ) . In 2000, a BBC study into the usage of CAM in the United Kingdom showed that one fifth of population had used some signifier of CAM in that twelvemonth ( Ernst & A ; White, 2000 ) . Alternate medical specialty takes the signifier of many methods. There are five chief classs of CAM which include ; alternate medical systems, biologically based therapies, manipulative therapies, mind-body theories and energy therapies ( Mainardi, Kapoor & A ; Bielory, 2009 ) . The most popular therapies in 2000 were osteopathy, chiropractic, stylostixis, homoeopathy and hypnotherapy ( Ernst & A ; White, 2000 ) . The term â€Å" placebo consequence † is normally used in the literature, but a consistent definition is yet to be agreed on ( Brinkhaus, Pach, Ludtke & A ; Willich, 2008 ) . The Latin definition of the word â€Å" placebo † means â€Å" I will delight † ( Niggemann, & A ; Gruber, 2006 ) which can be described as a positive curative result, happening after intercession of a physiological or psychological response ( Williamson & A ; Rankin-Box, 2009 ) , and can be dominated by ends, desires, outlooks and associated emotions ( Teixeira, Guedes, Barreto & A ; Martins, 2010 ) . The placebo consequence can be described as a neurophsyiological phenomenon ( Campbell, 2000 ) , and by looking at different illustrations of alternate medical specialty, the biological and psychological accounts of the consequence can be explored.AcupunctureAcupuncture is an ancient signifier of health care and focuses on handling unwellness through stimulation of the organic structure Ã¢â‚¬Ë œs self-healing powers ( Williamson & A ; Rankin-Box, 2009 ) . Acupuncture is based on ancient Chinese medical specialty and works to equilibrate the energy flow, â€Å" qi † , in the human organic structure by infixing acerate leafs into specific points on organic structure called â€Å" acupoints † which are located along â€Å" acmes † , which are the waies of energy in the organic structure ( Goddard, Shen, Steele & A ; Springer, 2005 ) . The effects of stylostixis on hurting can ensue in physiological and/or psychological responses of the organic structure, but grounds suggests there are biological foundations in this therapy ( Lundeberg, & A ; Stener-Victorin, 2002 ) . By looking at grounds for statements from a biological and psychological position, one can discourse the use of the placebo consequence in this type of alternate medical specialty. Biological Position Surveies utilizing antielectron emanation imaging ( PET ) and functional magnetic resonance imagination ( functional magnetic resonance imaging ) have demonstrated some biological grounds for the usage of stylostixis, proposing that there is more to the therapy than merely a curative consequence ( Teixeira et al. , 2010 ) . This can be explained by the activation of certain encephalon countries in the cardinal nervous system ( Goddard et al. , 2005 ) . With the usage of functional magnetic resonance imaging and PET scans, there is grounds that when specific points on the organic structure are subjected to acupuncture, there is activation in specific parts of the encephalon. This allows one to distinguish between existent stylostixis and outlook ( Lewith, White & A ; Pariente, 2005 ) , demoing that stylostixis does hold a biological account. The limbic system may besides be involved in the emotional production of laughter and shouting which is common in stylostixis ( Campbell, 2000 ) . Evidence demoing that there is inactivation of the amygdaloid nucleus and hypothalamus during stylostixis, implies that there is a specific function for the limbic system in stylostixis therapy ( Hui, Marina, Liu, Rosen & A ; Kwong, 2010 ) . Hui et Al. ‘s ( 2010 ) work supports the biological foundations in the usage of stylostixis, but besides recognises the of import function of emotion in the therapy, which would supply grounds for the use of the placebo consequence. Lundeberg and Stener-Victorin ( 2002 ) emphasis the importance of biological deductions in effects of stylostixis. They describe how the physiological stimulations of musculus contractions and certain organ maps are similar to effects of exercising, i.e. the release of endogenous opiods and Pitocin in both stylostixis and exercising ( Lundeberg, & A ; Stener-Victorin, 2002 ) . Lundeberg ‘s earlier survey with Andersson ( 1995 ) besides found that stylostixis excites the same receptors and afferent nervus fibers in the stirred tissue as in physical exercising ( Andersson & A ; Lundeberg, 1995 ) . Psychological Position Acupuncture is based on the organic structure ‘s self-healing powers ( Williamson & A ; Rankin-Box, 2009 ) , so there is ground to reason whether stylostixis effects are merely a psychological ( placebo ) response with small biological account ( Enck, Klosterhalfen & A ; Zipfel, 2010 ) . Goddard et Al. ( 2005 ) depict how the placebo consequence is utilised in therapy, non merely by the esthesis of the needle, but chiefly the attending, compassionate attention, self-awareness and transition of outlooks involved in the process ( Goddard et al. , 2005 ) . Expectation is a cardinal facet of non lone stylostixis, but many other types of alternate medical specialty. Astin et Al. ( 1998 ) conducted a reappraisal into why people use CAM and found that the chief grounds were ; the patient ‘s deficiency of response to conventional intervention, the patient ‘s petition, belief in efficaciousness and fewer inauspicious effects ( Astin, Marie, Pelletier, Hansen, & A ; Haskell, 1998 ) . It is the belief and outlook of utilizing alternate medical specialties which demonstrates grounds for the placebo consequence, and it is the people with high outlooks about the effects of stylostixis who show more response than those who do non believe in the intervention ( Teixeira et al. , 2010 ) . This psychological factor is of import in stylostixis as the effectivity of the intervention and reconstructing the natural flow of critical energy ( Hui et al. , 2010 ) involves bodily centripetal stimulation ( Andersson & A ; Lundberg, 1995 ) and if the patient does non believe in the procedure, they will non experience the same effects ( Goddard et al. , 2005 ) . Other facets of the therapy involve the attending and interaction between the patient and healer. A reappraisal into the increased usage of CAM in the UK showed that one of the factors forcing patients off from conventional wellness attention is the dissatisfaction of the patient-doctor relationship, which attracts people to a more holistic method where the intervention was more individualized ( Little, 2009 ) i.e. in alternate medical specialty. The individualized, manual scrutiny agencies increased communicating between the patient and healer and this societal communicating can be in the signifier of touch. The psychological importance of touch plays a cardinal function in stylostixis and the patient ‘s experience consequences in feelings of improved self-image, increased self-worth and well-being. These positive feelings are what patients base their beliefs about the effectivity of stylostixis on and believe their organic structure is mending ( Campbell, 2000 ) . This shows how alternate medical specialty utilises the placebo consequence where it is the patient ‘s belief that has the greatest impact on the efficiency of the therapy. The ambiance involved in alternate medical specialty plays a function in the result, and consequences show that when patients carry out their ain stylostixis after being taught the process, they report that their ain attempts are less successful than when the healer provides the attention ( Campbell, 2000 ) . This demonstrates once more the importance of psychological factors which provides grounds for the usage of the placebo consequence.HomeopathyHomeopathy falls under the alternate medical systems class of alternate medical specialty ( Mainardi, Kapoor & A ; Bielory, 2009 ) and can be defined as â€Å" a curative method utilizing readyings of substances whose effects when administered to healthy topics correspond to the use of the upset ( symptoms, clinical marks, pathological provinces ) in the single patient † ( Swayne, 2002, cited in Ernst, 2005 ) . It is a widely used type of alternate medical specialty and uses the basic premiss that â€Å" like is cured by like † ( Shang et al. , 2005 ) . Homeopathic medical specialty is used with the purpose of exciting a individual ‘s innate capacity for self-regulation and self-healing ( Weatherley-Jones, Thompson & A ; Thomas, 2004 ) . By researching the biological and psychological grounds, one can understand the use of the placebo consequence in this type of alternate medical specialty. Biological Position Homeopathic medical specialty can be used to supervise internal fluctuations via centripetal feedback through splanchnic or bodily perceptual experience, and patients interpret their feelings as positive or more negative emotional feelings ( Teixeira et al. , 2010 ) . This shows support for the biological position for utilizing alternate medical specialty, where patients construe how their internal organic structure province feels, which consequences in the healing procedure. Thompson ( 2010 ) looked into the usage of alternate medical specialty in menopausal adult females and chest malignant neoplastic disease subsisters, and provides grounds that reveals an association between intervention of homeopathic medical specialty and betterment of symptoms and quality of life for the patients ( Thompson, 2010 ) . Thompson discussed the clinical benefits of homoeopathy and concluded that the benefits can non be explained by the hypothesis that the therapy is merely a placebo consequence ( Thompson, 2010 ) . This grounds supports the impression that there is biological grounds behind homoeopathy, nevertheless, compared to acupuncture, there is significantly less grounds for this type of alternate medical specialty. Psychological Position Homeopathy is similar to acupuncture in the manner that the non-specific curative effects of the doctor-patient relationship, the personal intervention and deficiency of inauspicious effects all contribute to making positive outlooks of the therapy ( Teixeira et al. , 2010 ) . This relationship between outlook and the consequences of therapy provides grounds that this type of alternate medical specialty uses the placebo consequence, by trusting on patients ‘ beliefs that the therapy will work. Therapists might utilize techniques to reenforce these beliefs by utilizing verbal suggestions during the intervention and making a suited environment. The patient-therapist relationship plays a cardinal function in homeopathic therapy, and the healer can organize powerful confederations with their patients by sharing strong beliefs ( Shang et al. , 2005 ) . Homeopathy is a holistic method and focal points on handling the whole individual, so making non-therapeutic effects will heighten the patients ‘ beliefs that the therapy is mending them. It is besides the belief that the physicians understand the unwellness and the effects of the intervention that enhances the patients ‘ outlooks that the methods will work and therefore will increase their opportunities of recovery ( Margo, 1999 ) . Developing trust and strong relationships could take clip to organize, but over clip patients go more confident in the therapy, which consequences in new beliefs about wellness, unwellness and the organic structure being formed ( Barry, 2006 ) ( Weatherley-Jones, Thompson & A ; Thomas, 2004 ) . The grounds shows how the placebo consequence is utilised in homoeopathy by working towards a positive curative result ( Williamson & A ; Rankin-Box, 2009 ) , and maintained by developing patients ‘ outlooks of the alternate methods of intervention. Research has suggested that many scientists think that the usage and effects of homoeopathy violates natural Torahs and some conclude that any clinical consequence must be a placebo consequence ( Linde et al. , 1997 ) ( Niggemann & A ; Gruber, 2006 ) . However, one must take into consideration that this is simply another manner of looking at the grounds, and there is support for viing theories.To What Extent Does Alternative Medicine Utilise the Placebo Effect?By critically looking into the biological and psychological facets of stylostixis and homoeopathy, the extent to which the placebo consequence is utilised in these methods can be generalised to other types of alternate medical specialty. In footings of the grounds for both sta tements, stylostixis shows valid grounds that there is a biological footing back uping the therapy and surveies utilizing functional magnetic resonance imaging and PET scans have shown that specific encephalon countries are activated when specific acupoints are stimulated ( Teixeira et al. , 2010 ) ( Goddard et al. , 2005 ) ( Lewith, White & A ; Pariente, 2005 ) . Homeopathy besides has a biological footing behind the therapy and research has shown an association between homeopathic intervention and positive effects on patients ‘ wellness and quality of life ( Thompson, 2010 ) . There is a important sum of psychological support for the usage of alternate medical specialty, chiefly because alternate medical specialty is a move off from conventional medical specialty. A motivation for increased usage of alternate medical specialty develops when there is a deficiency of response to conventional intervention. The usage of CAM is prevailing in patients with Alzheimer ‘s disease, multiple induration, malignant neoplastic disease, A back jobs, anxiousness, concerns, and chronic hurting ( Astin et al. , 1998 ) , where there is no specific medical intervention. Astin et Al. ( 1998 ) predict that as the general population ages, the incidence of chronic unwellnesss will besides increase, which will take to increased usage of such interventions ( Astin et al. , 1998 ) . Other facets of the effectivity of such interventions are linked to the psychological experience involved. The ambiance, the patient-therapist relationship ( Barry, 2006 ) ( Weatherley-Jones, Thompson & A ; Thomas, 2004 ) ( Little, 2009 ) ( Campbell, 2000 ) and the outlooks of the results of alternate therapies ( Shang et al. , 2005 ) ( Margo, 1999 ) ( Teixeira et al. , 2010 ) ( Goddard et al. , 2005 ) are all key in both stylostixis and homoeopathy, which all contribute to the use of the placebo consequence. In decision, holding demonstrated the biological and psychological statements for the usage of the placebo consequence in stylostixis and homoeopathy, one can generalize to alternate medical specialty as a whole and say that the placebo consequence plays an of import function in the effectivity of these signifiers of interventions. There has been a high degree of research into the usage of alternate medical specialties, and although CAMs are widely used across the universe, there are few empirical surveies looking into the safety and efficiency of such interventions ( Tilburt et al. , 2009 ) . This is because alternate medical specialty plants by handling the individual as a whole, and efficiency of such methods rely on outlooks and belief on portion of the patient. This, hence, supports the impression that the placebo consequence plays a important function in the sensed result of alternate processs.Word count – 1959 words

Submarine Escape Procedures

Michael Menor Professor Cady English 151 25 February 2013 Submarine Escape Procedures There are many catastrophes that can affect the operation of a submarine; fire and flooding can crimple a submarine completely if either is not resolved quickly. Submariners are trained to combat all forms of fire and flooding in different scenarios that are closely monitored in Submarine School. As a last resort, sailors are also trained in submarine escape in the very rare occasion that they must escape from the ship.Submarine escape is only effective at depths less than 600 feet; escape any greater depth would be impossible. Michael Menor deployed with two nuclear fast-attack submarines; the USS Santa Fe and the USS Albuquerque; during his four and a half year enlistment in the United States Navy. He is well versed in submarine escape and hopes that this will give you an understanding on how to escape from the depths of the sea. Every ship is equipped with two escape trunks, or hatches as some ma y call it; one forward and aft, both of which have similar dimensions and operation procedures.Each trunk is able to hold two escape personnel. The Submarine Escape Immersion Equipment; also known as a SEIE Suit; is a last resort option if a Deep Submergence Rescue Vehicle, or DSRV is unable to save personnel from a disabled submarine. The suit is a single piece construction capable of controlling pressure to prevent decompression sickness, or â€Å"the bends†, which is a side effect of rapidly ascending from ocean depths. Each suit is also equipped with a life boat that is contained within a pouch attached to the left hip.Familiarity with the escape hatch valves is not required; all operations are handled by personnel from within the ship. For the purposes of this procedure we will call these personnel â€Å"Supervisors,† since they are usually experienced supervisory personnel with the knowledge of operating the escape hatch. Depending on where the casualty, is you w ill always want to choose the escape trunk that is not in the affected compartment. Whether it is flooding in the forward compartment; your escape will be in the aft escape trunk in the Engine Room. The same pplies to a casualty in the aft compartment; your escape will be via the forward escape trunk. During this procedure you will be performing all actions from within the forward escape trunk. On the rare occasion that submarine personnel are not able to stop flooding in the engine room that leaves the ship sinking into the depths, and laid to rest on a sea shelf 500 feet below the surface. You will then need to don a SEIE suit by placing both feet into the suit and taking the zipper, which is placed on the outer side of the left leg and pulling this up until it is at your belly button.As you would put on a coat; place both arms into each sleeve equipped with rubber gloves and flip the hood onto your head. You must then pull on the zipper, which continues upwards centered on your c hest, and up to the hood. One common issue that can occur is the zipper getting stuck, or feeling as if it will not budge—remember that it was designed to keep water out of the suit—if this happens you will need to request the assistance of someone else.Now that you have the suit on you will need to make your way to the escape hatch ladder and climb into the 6 foot cylindrical space, which is only designed to hold two escape personnel; the two of you will be standing directly across from each other with your backs against the bulkhead. There is a charging hose attached to the left arm of your suit, attach this hose to the charging manifold on the bulkhead (wall) located to your left; the charging hose will inflate your suit to create a bubble barrier between you and the outside pressures of the ocean.Remember this is your source of oxygen, so continuing to keep the charging hose connected during your time in the escape hatch is crucial. As your suits are being charged please keep your feet away from the lower hatch as the Supervisors begin close and seal it. Once it is confirmed sealed a rush of water will begin to flood the hatch. Due to the buoyancy of your inflated suit you will begin to float; do not let this happen. To prevent this there is a handle to your right that you will be able to use to maintain your grip and keep you anchored safely.Supervisors will then pressurize the hatch to match the outside pressure outside of the hull. The first person that entered hatch will be the first one to escape; once the hatch is clear the second person will wait 30 seconds and follow to prevent getting entangled with one another. Since you are the lucky one to enter first, you will get to escape first. Supervisors will open the upper hatch; continue to maintain your grip until the upper hatch has reached its fully opened and locked position. Supervisors will use a wrench or hammer to knock on the lower hatch three times.This will give you the signal t hat the upper hatch is clear and you can escape. Release your grip from both the handle and the charging manifold. Allow the suit to take over as its positive buoyancy lifts you out of the hatch and upwards to the surface. The suit is designed to maintain proper atmospheric pressure for your safety during the ascent; as you will be traveling about 30 feet per second. Upon reaching the surface ensure that you are floating on your back, while in this position you need to reach into the pouch on your left hip and remove the life raft; pull on the yellow handle and allow the raft to self-inflate.Once inflated pull yourself onto the raft; during this time you can unzip the hood of your suit. The raft comes equipped with a drogue, water desalination kit, and equipment such as smoke signals, and flares to assist with your rescue. Congratulations on your successful escape; now you will wait for rescue personnel to find you and the others from your ship. At the surface it is highly recommend ed to regroup with other personnel from the ship and tie your rafts together. This will create a larger object for rescuers to spot during their search.

Death of a Salesman Review

Death of a Salesman Review Free Online Research Papers Willy Loman’s death was caused by his inability to face reality and could have been avoided if he and his family had been honest with themselves regarding their shortcomings. Instead, they lived in a world of denial, which spawned additional lies. Willy’s character deficiencies, moral indiscretions, and inability to differentiate past from present created nearly all of the family’s issues and led to his demise. Willy Loman is a man with two distinct personalities. The first personality lives in the present where he is a broken man in his early sixties, who feels he is more valuable to his family dead than alive. Willy is nearly unable to tell the truth about any part of his life. He is also a horrible husband, who has been unfaithful to his wife Linda and routinely responds to her with anger. Willy is ineffective as a salesman who has been stripped of his salary and eventually he is fired. Lastly, Willy is a proud man, too proud to accept a job working for Charley, but that does not keep him from borrowing his money each week while telling Linda that he earned it selling his wares. The second personality is living fifteen years ago, believing that he and his family are bound for greatness. One recurring flashback involves Willy’s son Biff when he was a high school football star. Most of these flashbacks involve his recently deceased brother Ben, who achieved all the success that Willy desires for himself. The effect of these two personalities was extremely apparent and painful for Willy’s family. One moment Willy would fondly recall Biff’s football career and then criticizes him for his inability to hold a job, the next minute. In end, Biff began to understand his own problems and attempted to explain that he was a â€Å"phony.† Willy could not recognize or grasp Biff’s realization, due to his inability to separate the present from the past. Further moral and character traits about Willy Loman include his unquenchable desire to excel in business, at any cost. He views business success as one of the significant barometers of for a man. Willy would boast about his sales or his wonderful sons, like most everything else he said, these stories were fabrications. Lastly, Willy was afraid to face reality and in the end, he showed exactly how cowardly he was, by committing suicide. Willy Loman’s decisions caused terrible pain in the lives of his family. The best example was when Biff was failing mathematics in high school. His teacher, and Bernard the neighbor, constantly reminded Biff of how serious this situation could be to his future. Biff did not change his habits and the teacher failed him. Willy did not force Biff to take summer school and Biff did not graduate. Willy did not help Biff to understand the ramifications of his actions and Biff struggled to find work as an adult. Research Papers on Death of a Salesman ReviewHonest Iagos Truth through DeceptionStandardized TestingCapital PunishmentArguments for Physician-Assisted Suicide (PAS)The Effects of Illegal ImmigrationPersonal Experience with Teen Pregnancy19 Century Society: A Deeply Divided EraRelationship between Media Coverage and Social andHip-Hop is ArtHarry Potter and the Deathly Hallows Essay