Lake Description free essay sample

Descriptive Essay Lake Panonica On a hot summer day, the only good place to go is to the lake. You would go out to the lake to enjoy the water, the sun, the activities that are happening, or just to be with family and friends. We’re lucky enough to have such a lake right in the centre of our town. When youre at the lake, there are some very distinct smells. The salty smell of water blended in with the nature and the trees surrounding you which makes you feel as if you were miles away from the city, somewhere on the coast. You can also enjoy the sweet coconut smell of sun tanning lotion that people put on themselves while they lay into the sun to basically cook. But if youre looking for a quiet relaxation at the lake, I dont think that will work out too well. We will write a custom essay sample on Lake Description or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page The lake is always really loud throughout the day. Youll definitely be able to hear the laughter and the excitement of children as they splash around in the lake, as well as the large amount of people talking and just basically having fun.Also the music from the nearby cafe is quite deafening, you can even hear it outside the margins of the lake. While youre at the lake you can always get involved in some fun activities, if you arent able to relax. You can go exercise on various machines, play volleyball in the sand, unless you don’t want get a bit dirty and sweaty, you can go to the waterfall and just enjoy the massaging effect of the water. In case you get hungry, there are always little stands with ice cream and soda to freshen you up even more. Overall the lake is a lot of fun to go to if you just want to get away from the busy, smelly city that you live in. If you are there early enough, for instance if you want to avoid the big crowd that comes in around noon, you will be able to see a beautiful, bright sunrise and if you enjoy staying out on the beach until the evening, Im sure you can catch a calming and loving sunset.

Feudalism

Feudalism Introduction The history of the Middle Ages and the Renaissance continues to attract the attention of many contemporary historians. Much attention is paid to such a concept as feudalism and its major peculiarities. Researchers focus on such questions as the evolution of this socio-political system, conflicts between various interest groups as well as the reasons why it eventually fell into oblivion.Advertising We will write a custom research paper sample on Feudalism specifically for you for only $16.05 $11/page Learn More This paper is aimed at discussing the major historiographic views on this system. In particular, one should mention that feudalism can be interpreted from a political and legal perspective. This research paradigm is supposed to examine the relations between the main stakeholders such as lords and vassals. From this viewpoint, the main characteristic of feudalism is the decentralization of authority. In turn, some scholars prefer socio-econ omic analysis of this phenomenon. In particular, they regard feudalism as a system that legitimized the exploitations of peasants by the aristocracy. One should keep in mind that contemporary researchers such as Marc Bloch tend to combine these historiographic views. These two interpretations form the basis of their discussions. This is why it is necessary to analyze these approaches in great detail. Furthermore, one should mention that some historians such as Susan Reynolds believe that the concept of feudalism is rather contradictory and it may not fit various societies which existed at that time. Overall, it is possible to argue that current historiographic views on this period can supplement each other. Yet, none of them can fully explain the complexities of this political, economic, and legal system which could vary across regions and evolve with time passing. This is one of the main arguments that should be examined more closely. Critique of the major historiographic views Pol itical and legal interpretation One should mention that some historians such as Franà §ois-Louis Ganshof concentrate primarily on the legal and political foundations of feudalism. Researchers, who accept this approach, regard feudalism as a body of institutions that regulated the relationship between the landowners who provided tenure and knights offering military service1. Therefore, one can say that feudalism is primarily aimed at facilitating the exchange between stakeholders. This historiographic view can be important for understanding the work of institutions which were supposed to re-enforce the rights of these stakeholders; for instance, Franà §ois-Louis Ganshof examines the institution of vassalage which was supposed to reconcile the interests of landlords and knights2.Advertising Looking for research paper on history? Let's see if we can help you! Get your first paper with 15% OFF Learn More Moreover, according to political and legal interpretation s, feudalism has several important characteristics. In particular, one should speak about the decentralization of authority which means that kings could not impose their will on landowners. Additionally, much attention should be paid to land as the main source of authority. This approach implies that during the period, states in the modern sense of that word were only at the stage of formation. Furthermore, according to this approach, feudalism can be viewed as a system for recruiting military professionals who were critical for the sustainability of the communities which existed at that time. This view of feudalism is one of the major research paradigms that can used for examining medieval societies. Overall, this approach is helpful for analyzing the main political and legal norms of the society. Moreover, this framework can be useful for analyzing the way in which the empowered interest groups regulated their relations. Nevertheless, there are several important limitations of thi s approach. In particular, this historiographic view completely excludes peasants who had no political or legal representation. It should be noted that these stakeholders also played a critical role for the sustainability of feudal societies. Furthermore, this historiagraphic approach does not show how these people could oppose to the existing hierarchy. For instance, one can speak about anti-feudal rebellions that took place in England and France3 in the twelfth century. Therefore, this particular approach can lead to the exclusion of many narratives that are important for understanding the peculiarities of this historical period. This framework can certainly explain the behavior of people who set the legal and political norms of feudal societies. However, one should pay more attention to people who were underrepresented due to existing social, political, and legal norms. The voices of these people could be almost completely silenced. This is one of the limitations that should be c onsidered by people who study the development of feudal societies. Socio-economic interpretation Additionally, it is possible to focus on the economic interpretation of feudalism. This approach is aimed at discussing the experiences of various social groups. Therefore, feudalism can be defined as the political and legal system which was supposed to subordinate peasantry to the interests of the landowning aristocracy4.Advertising We will write a custom research paper sample on Feudalism specifically for you for only $16.05 $11/page Learn More Therefore, this approach implies that this socio-political system can be regarded primarily as the system of exploitation. Thus, this view of feudalism was often adopted by Marxist historians who attached much importance to the concept of class struggle. Although, this particular concept may not be applicable to feudal societies, social and economic interpretations are not fully rejected by the modern scholars. Historia ns who adopt this approach pay attention to the experiences of the most underprivileged classes. One can distinguish the following characteristics of the feudal system: the use of coercion to subdue underrepresented groups; social stratification; unequal bargaining power of different stakeholders5. Admittedly, this approach should not be disregarded because it is important for understanding the experiences of different social groups. Nevertheless, this interpretation does not fully explain the conflicts between the most powerful stakeholders in the feudal society. In particular, one should speak about monarchs and landlords. It should be mentioned that sometimes, vassals could have conflicting obligations to monarchs and land owners6. In other words, one cannot examine this period only from an economic viewpoint because this approach cannot fully the power struggles which existed at that period. This is one of the drawbacks that should not be disregarded. This historiographic cont inued to be used by historians because it is more inclusive, especially in comparison with the paradigm developed by Franà §ois-Louis Ganshof who examines primarily the interactions between stakeholders who could better protect their interests. Marc Bloch’s views on feudalism It should be mentioned that some historians attempt to combine legal and socio-economic views on fuedalism. For instance, one can speak about the works of Marc Bloch. He focuses on the following characteristics of feudalism:Advertising Looking for research paper on history? Let's see if we can help you! Get your first paper with 15% OFF Learn More the subordinate position of peasantry the decentralization of authority; the use of service tenement instead salary; regular conflicts between kings and landlords7. To some degree, this method lays stress on the legal and political structures of feudalism, but at the same time, it can throw light on the experiences of different social groups. It is important to remember that Mark Bloch distinguishes two stages of feudalism. In particular, this historian believes that economic transformation of feudal societies led to the eventual centralization of power and formation of more powerful monarchies. Overall, Marc Bloc believes that the economic perspective should not be excluded because the intensification of trade and commerce strengthened the bargaining power of monarchs8. Overall, Marc Bloch’s approach is more beneficial because it enables the author to examine the experiences of different stakeholders who represented the medieval society. Additionally, this historiographic view is advantageous because it shows how feudal system evolved and why it eventually disappeared. In this case, one should mention that technological and economical development diminished the role of agriculture and land ownership9. In turn, growing trade could lead in the strengthening of the centralized power. In particular, this paradigm demonstrates the connections between economy, law, and politics. These are the main strengths of this framework. Nevertheless, this approach may not show how feudalism evolved in various in various cultural environments that could profoundly influence the interactions between different groups. Additionally, this approach does not show how individual decisions of monarchs or landlords could have shaped the development of feudalism. This is one of the limitations that should be considered because researchers should not assume that the development of this socio-political system could be predetermined. To a great extent, this perception reduces the role of a separate individual who could also shape the way in which a certain community could evolve. Re-evaluation of feudalism as a concept These approaches that have been described are based on the premise that feudalism as a system existed in various regions or countries. Furthermore, they imply that there are certain common principles which are inherent to the nature of this political and legal system. Therefore, the experiences of people could be similar in such countries as England, France, Germany, and so forth. Nevertheless, one should also keep in mind that some researchers do not believe that feudalism was a universal and consistent phenomenon. This opinion is expressed by different historians such as Susan Reynolds10. This approach implies that it is not permissible to generalize the experiences of different countries. For instance, the institution of vassalage was not the same in different medieval societies. The customs adopted in different countries could differ drama tically. This is one of the points that should be considered. This is why even researchers such as Marc Bloch focus on different lands and regions while discussing feudalism. Apart from that, researchers may examine the distinctions between feudalism in England and Scotland11. Overall, it is important to examine local customs that were not similar to one another. Furthermore, these customs could evolve significantly with time passing. This is one of the reasons why researchers speak about the existence of pre-feudal and post-feudal societies12. In many cases, these societies had the main characteristics identified by Ganshof and Bloc. Moreover, researchers argue that the relations between various groups were not always the same because they could be influenced by the cultural norms established in various feudal societies. This approach implies that historians should not try to twist historical evidence so that it could match historical constructs or concepts such as feudalism. Inste ad, they need to concentrate on primary evidence which can throw light on the diversity of feudal societies. Thus, one can say that feudalism can be depicted as a changing and diverse phenomenon that cannot be described with the help of a single model. These are the main peculiarities of this historiographic view. The main advantage of this approach is that it urges researchers to focuses on the particularities of the feudal system in different countries. In this way, historians can gain better insights into various aspects of feudalism. This historiographic view is also popular since modern researchers examine the cultural peculiarities of feudalism. Conclusion These examples demonstrate historians do not have the same perception of feudalism. The differences can be explained by the fact that researchers focus on different aspects of this historical period. In particular, it is possible to speak about the distribution of power in the society and the norms regulating the relations b etween the main stakeholders. In turn, scholars can focus on the study of economic development and the way in which some social groups could be marginalized. Apart from that, many researchers such as Marc Bloch tend use each of these paradigms. Apart from that historians may discard the ideas that feudalism was a universal construct that existed in different countries. In particular, it is important to mention that feudalism could take different paths, and one cannot say that it could always fit the models constructed by historians. Overall, none of the historiographic views discussed in this paper can be dismissed because each of them can throw light on the experience of different social groups. Furthermore, the use of these paradigms is important for understanding the evolution of this socio-political system. These are the main aspects that can be distinguished because they can be helpful for understanding the main peculiarities of feudalism. Bibliography Bloch, Marc. Feudal Socie ty. Translated by Leonard Manyon. London: Routledge. 1962. Braun, Jerome. Democratic Culture and Moral Character: A Study in Culture and  Ã‚  Personality. New York: Springer Science Business Media, 2013. Ganshof, Franà §ois-Louis. â€Å"Benefice and Vassalage in the Age of Charlemagne.†Ã‚  Cambridge Historical Journal 6, no. 2 (1939): 147-175. Hammond, Matthew, New Perspectives on Medieval Scotland, 1093-1286. New York, Boydell Brewer Ltd, 2013. McKitterick, Rosamond, and Michael Jones. The New Cambridge Medieval History:  Volume 6, C.1300-c.1415. Cambridge: Cambridge University Press, 2000. Murray, Mary. The Law of the Father?: Patriarchy in the transition from feudalism to  capitalism. New York: Routledge, 2005. Reynolds, Susan. Fiefs and Vassals: The Medieval Evidence Reinterpreted. New York, Clarendon Press. 1994. Sanderson, Stephen. Social Transformations: A General Theory of Historical  Development. New York: Rowman Littlefield, 1999. Tendler, Joseph. Oppone nts of the Annales School. London: Palgrave Macmillan, 2013. White, Lynn. Medieval technology and social change. Oxford University Press. 1962. Footnotes 1 Joseph Tendler, Opponents of the Annales School (London: Palgrave Macmillan, 2013), 158. 2 Franà §ois-Louis Ganshof, â€Å"Benefice and Vassalage in the Age of Charlemagne,†Ã‚  Cambridge Historical Journal 6, no. 2 (1939): 147. 3 Rosamond McKitterick and Michael Jones, The New Cambridge Medieval History:  Volume 6, C.1300-c.1415 (Cambridge: Cambridge University Press, 2000), 457. 4 Stephen Sanderson, Social Transformations: A General Theory of Historical  Development (New York: Rowman Littlefield, 1999), 157. 5 Mary Murray, The Law of the Father?: Patriarchy in the transition from feudalism to  Capitalism (New York: Routledge, 2005), p. 10. 6 Franà §ois-Louis Ganshof, â€Å"Benefice and Vassalage in the Age of Charlemagne,†Ã‚  Cambridge Historical Journal 6, no. 2 (1939): 175 7 Marc Bloch, Feudal Society, t rans. Leonard Manyon (London: Routledge. 1962), 13 8 Marc Bloch, Feudal Society, trans. Leonard Manyon (London: Routledge. 1962), 69. 9 Lynn White, Medieval technology and social change (Oxford University Press. 1962), 63. 10 Susan Reynolds, Fiefs and Vassals : The Medieval Evidence Reinterpreted (New York: Clarendon Press, 1994), 32. 11 Matthew Hammond, New Perspectives on Medieval Scotland, 1093-1286 (New York, Boydell Brewer Ltd, 2013), 10. 12 Jerome Braun, Democratic Culture and Moral Character: A Study in Culture and  Personality (New York: Springer Science Business Media, 2013), 119.

Bordetella pertussis (bacterium)

Bordetella pertussis (bacterium) Bordetella pertussis is the bacterium that causes pertussis, otherwise known asor whooping cough . Despite vaccination, incidence of pertussis cases have been growing over the last two decades. Current vaccines lack the ability to give long-lasting immunity and must be improved. Complement evasion molecules would make good candidates for vaccine components, because the complement system is essential in the killing of B. pertussis. The complement system is a first line of defense against colonization of bacteria in host tissue. Many bacteria employ complement inhibitors or attract human complement inhibitors to their surface. B. pertussis is no exception on this, however not much is known about the way B. pertussis evades the complement system . Prior to this study a few potential complement inhibitors of B. pertussis were identified. In this study we seek to characterize these proteins in a series of functional immune assays. Under these experimental conditions, we were not able to determine the function of the potential complement evasion molecules. BACKGROUND Bordetella pertussis is a Gram-negative bacterium and the causative agent of pertussis, also called whooping cough. Pertussis is a human-restricted disease of the respiratory tract and highly contagious ( en is dit zo? REF). Regular bouts of coughing produce airborne droplets through which B. pertussis can be transmitted (Jongerius et al. 2014). The disease was on the verge of eradication due to worldwide vaccination, but has been re-emerging in the last two decades. In 2008 there were 16 million cases of pertussis globally as estimated by the World Health Organisation. Possible explanations for the re-emergence are waning of immunity – since in the 1990s a different vaccine was introduced giving less enduring protection – or bacterial strain adaption (Mooi et al. 2014). Like many pathogens B. pertussis developed strategies to evade or repress the host response for successful colonization (REF). Little is known about the mechanisms by which B. pertussis escapes clearanc e by the complement system, a first line of defense in the immune response. Identification and characterization of these immune evasion molecules may lead to the discovery of new targets for anti-inflammatory drugs or new components for vaccines. Here, we try to characterize several potential complement inhibitors of B. pertussis, identified by phage display and genome analysis. Bordetella pertussis virulence factors B. pertussis expresses a variety of virulence factors that enable the bacteria to colonize the upper respiratory tract. The transcription of the majority of these virulence factors are regulated by the activity of the proteins BvgA and BvgS. BvgAS is a two-component system that controls gene expression in response to changing environmental conditions, such as temperature (Fedele et al. 2014). After inhalation the bacteria adhere to the ciliated epithelial cells of the larynx, trachea and bronchi, where they produce secreted toxins and membrane-bound molecules that contribute to the adherence (REF). The toxins damage the mucous layer of the respiratory tract, contributing to the pathogenesis of pertussis. For example tracheal cytotoxin (TCT) is proposed to cause ciliostasis, impairment of ciliary movement, which may explain the intense coughing that characterizes pertussis, as a way to clear excessive mucus (Jongerius et al. 2014). Other secreted toxins include pertussis toxin (PT) an d adenylate cyclase toxin (ACT), which are toxic to host cells including neutrophils, monocytes and lymphocytes (Jongerius et al. 2014 ). Successful colonization is both dependent on the capacity to adhere to cells in the respiratory tract and the ability to ward off the immune response. PT and ACT both repress the immune response by targeting airway resident macrophages and neutrophil recruitment to the airways (Carbonetti et al. 2010). The membrane-bound adhesins include fimbriae (Fim), filamentous hemagglutinin (FHA) and pertactin (PRN), which in addition to facilitating the first step of infection are also suggested to suppress the initial inflammatory response to the infection (Melvin et al. 2014). For example, FHA-deficient Bordetella strains were shown to induce an increased production of pro-inflammatory cytokines, such as IL-17, and increased recruitment of neutrophils to the site of infection when compared to wild-type bacteria (Henderson et al. 2012). In addition to the i mmunomodulating properties of B. pertussis virulence factors, direct binding to components of the immune system, such as the complement system, is accomplished in order to reduce or inhibit the host immune response. This essential step in bacterial pathogenesis is called immune evasion (Rooijakkers et al. 2005). B. pertussis is known to express a small variety of proteins that affect complement-mediated killing: tracheal colonization factor (Tcf), Bordetella resistance to killing A (BrkA) and the autotransporter Vag8 (Jongerius et al. 2014). The complement system The complement system is part of innate immunity and an important host defense mechanism against invading pathogens. The complement system consists of approximately 40 proteins and is present in blood and mucosal tissue, such as the lining of the lungs where they interfere with colonization of bacteria. The system can be initiated through three different pathways: the classical (CP), the lectin (LP) and the alternative pathway (AP). All pathways lead to a cascade of several protein-protein interactions and proteolytic steps leading to cleavage of C3 and C5 in biologically active components. C3a and C5a are able to attract inflammatory cells to the site of infection and activate them. C3b is another cleavage product of C3 and when deposited on the microbial surface stimulates bacterial uptake by phagocytes in a mechanism called opsonization. Besides opsonization and recruitment of phagocytes the complement system can also directly kill bacteria by forming pores into the microbial memb rane and inducing lysis. The pore-forming heteromer is called the membrane attack complex (MAC) and is composed of C5b, C6, C7, C8 and C9. The classical pathway gets activated with binding of antibodies to the microbial surface. IgM or IgG bind to the first complement component C1q, which results in activation of serine proteases that cleave C2 and C4 which in turn form C4b2a, a C3 convertase. The same C3 convertase is formed upon activation through the lectin pathway, in which mannose-binding lectin-associated serine proteases cleave C4 and C2 upon binding of lectin to mannose on the bacterial surface. No specific signal is needed for the alternative pathway to form another C3 convertase: C3bBb, comprising of spontaneously hydrolyzed C3, or C3b generated by the CP/LP, and factor B that is activated by factor D. The C3 convertases (C4b2a and C3bBb) switch to C5 convertases in response to high levels of C3b deposition on the bacterial surface (Jongerius et al. 2007). The complement s ystem does not only directly or indirectly kill bacteria but also has a role in regulating adaptive immunity. Besides regulating B-cell immunity, complement-mediated signaling directly stimulates and modulates T-cell responses (Jongerius et al. 2014) and promotes antigen processing by antigen-presenting cells (Serruto et al. 2010), indirectly influences T-cell activation. On the downside, over-activation or lack of down-regulation of the complement system can result in systemic inflammation during sepsis (Jongerius et al. 2007) and autoimmune diseases when host cells are recognized as non-self and damaged by complement activation (Meri et al. 2013). Complement evasion by Bordetella pertussis In order to survive and successfully colonize the host the bacteria must have strategies to evade the early immune response. It seems especially necessary for B. pertussis to prevent complement activation because it does not express antigen O (Marr et al. 2011). Antigen O is the chain of repetitive oligosaccharides of the lipopolysaccharides in the membrane of most Gram-negative bacteria and works as a protective shield. The Bordetella strains B. parapertussis and B. bronchoseptica express liposaccharide containing this O-antigen, but despite being more virulent B. pertussis lacks O-antigen in its cell wall. B. pertussis expresses a different kind of surface polysaccharide called Bps (Bordetella pertussis polysaccharide) which seems to provide serum resistance, since Bps mutant strains were more sensitive to complement-mediated killing then wild type bacteria (Ganguly et al. 2014). In addition to polysaccharides B. pertussis is known to express several other complement evasion molecu les. Mutants lacking Bordetella autotransporter protein-C (BapC) were less resistant to serum killing, although the mechanism of resistance is yet to be identified (Noofeli et al. 2011). Another autotransporter of B. pertussis, Bordetella resistance to killing A (BrkA) that promotes attachment of the bacteria to human cells, is involved in complement evasion as well (Jongerius et al. 2014). Studies have shown that BrkA reduces C3 and C4 deposition and inhibits formation of MAC (Barnes et al. 2001). BrkA did not affect C1 deposition levels, suggesting BrkA only inhibits the classical pathway however the precise mechanism remains unknown (Barnes et al. 2001). Besides binding to complement components and thereby inhibiting their action by proteolysis or inducing conformational changes, bacteria can also employ a different strategy: to recruit and activate human complement inhibitors. The main regulators of the classical pathway are C4b-binding protein (C4BP) that B. pertussis binds to its surface with filamentous hemagglutinin (FHA) (Berggard et al. 2001), and C1 esterase inhibitor (C1-inh) recruited by B. pertussis autotransporter Vag8 (Marr et al. 2011). Factor H (fH) regulates the activity of the alternative pathway. The AP does not need a specific signal, making every unprotected surface vulnerable; therefore bacteria need to evade this pathway. Many bacteria do so by binding fH via a common binding site, forming a tripartite complex consisting of the microbial receptor, C3b and fH (Meri et al. 2013). This complex inhibits the opsonizing actions of C3b (Meri et al. 2013) and thereby protects the bacteria against phagocytosis. Recent studies show that B. pertussis binds fH at domain 20 (the common binding site) while fH remains its inhibiting properties (Amdahl et al. 2010), but a particular B. pertussis protein that binds fH has not been identified yet. Pertussis vaccines The whole cell pertussis (wP) vaccine was introduced in the 1950, efficiently lowering the cases of pertussis, which was the leading cause of child death before introduction of the vaccine. Unfortunately the vaccine was causing a lot of unwanted side effects in children. This had lead to introduction of an acellular pertussis (aP) vaccine, comprising of just several antigens. Although this vaccine provides a sufficient level of protection for infants to severe pertussis, the incidence of pertussis in adults has been increasing since the introduction of the aP vaccine in the 1990s (Mooi et al. 2013). More awareness and better diagnostics contribute to this increase in pertussis cases, but moreover the protection given by the aP is short-lived. Immunity generated by the wP vaccine is mediated largely by T-helper 1 cells (Th1), whereas aP vaccination results in antibodies that induce Th2 and Th17 responses. Natural immunity is associated with Th1 cells, and hence IFN- production, as is seen in children recovering from whooping cough (Higgs et al. 2012). The adaptive immunity provided by aP vaccination is mainly humoral, promoted by Th2 cells that seem to be less efficient than Th1 cells in clearing B. pertussis infections (Higgs et al. 2012). In addition the provided immunity by aP vaccination is not lasting as long as the wP (Mooi et al. 2014). This occurrence of waning immunity is proposed to be the main cause of re-emergence of infections with B. pertussis. In addition, there is evidence the bacteria have been genetically adapting to the aP vaccines, caused by antigenic variation and selection pressure. In The Netherlands, France, Finland and Japan there are strains circulating that do not express FHA, PT and PRN, components of the aP vaccine used in these countries (Mooi et al. 2014). Future vaccines should be improved by, for example, adding other antigen preparations to provide long-lasting immunity, and additionally to strengthen the immune response. By st rengthening innate immunity, the immune system will be able to directly eliminate the bacteria, preventing transmission and therefore also strain adaptation. The use of complement evasion molecules as vaccine targets would allow faster complement activation upon infection with B. pertussis. In this study we look to identify and characterize such attractive vaccine component candidates. Prior studies Prior to this characterization study a secretome phage display was constructed (Fevre et al. 2014). This phage display was used to identify potential immune evasion molecules. Phage display is the technique of expressing proteins on the surface of a bacteriophage. A phage library comprises of several phage clones that express different proteins, which retain their original shape and behavior. This allows selection of the displayed proteins based on affinity, with successive rounds of selection to identify proteins with high affinity for the selected targets. Secretome phage display, based on whole-genome phage display, is tailored for identification of immune evasion molecules with only secretome proteins being displayed. The bacterial secretome is the collection of all secreted and surface-bound proteins (Fevre et al. 2014). Phage display was performed for the secretome of Bordetella pertussis, with 3 rounds of selection and 7Ãâ€"107 phage clones. The phages were targeted on six co mponents of the complement system: alternative pathway regulating factor H (fH), the opsonin C3b and C3 together with C5 (the two mixed) and C8 together with C9. After the third round there were five hits: BP0069, BP3355, BP0173, BP1251 and fhaC. Supposedly BP1251 and fhaC seem to bind C8 and/or C9, BP0069 binds factor H and BP0173 and BP3355 are suggested to bind a mix of complement components. Analyzing information on chemical parameters (see table 1), gene alignment and genomic context (provided by NCBI Gene, NCBI Protein, BLAST and ExPASy ProtParam) might provide some clues of the functional properties of the proteins, but their complete function is yet unknown. BP0069 is a 43 kD protein which is 97% identical to ABC transporters from B. bronchispetica and around 30% identical to TRAP transporters from several bacteria species, both are transmembrane transporters for nutrients intake. BP3355 is a 18 kDa hypothetical protein, that has no evident homologues. BP0173 is a 24 kD hypothetical protein and BP1251 is a 26 kD putative toxin.

Vocabulary Game for English Language Learners (ELL students) Essay

Vocabulary Game for English Language Learners (ELL students) - Essay Example The game in this presentation is one that focuses on the use of prepositions and adjectives. This experience can be related to what I have learned about ELL and how they interact with material as well as the benefits of face to face interaction. It also relates to things like the development of literacy. â€Å"There is a growing concern over the ability of the educational system to meet the needs of the increasingly diverse multiethnic, multilingual classroom. Prominent among these needs is the acquisition of literacy skills. In recent years, researchers have begun to challenge simplistic notions about the development of English as a Second Language (ESL)1 literacy skills† (Geva, 2000). The game is basically a variation of tic-tac-toe. Most students, even those from other countries, are familiar with tic-tac-toe, and if they are not, it does not take long for the teacher to explain it, and for them to catch on during play. The game begins with the teacher using a whiteboard and marker to draw the tic-tac-toe grid. In each square of the grid, a preposition and adjective are placed, with the â€Å"to be† verb added where necessary. For example, in the first round, the grid may be â€Å"be afraid of,† â€Å"vote for,† â€Å"be confident in,† â€Å"be married to,† â€Å"take from,† â€Å"fight for,† â€Å"dream about,† etc., with one phrase in each square. The students then pair into twos. One student is X; the other is O. The students take turns using the preposition and adjective in their own example, to get the square. When the game is over, the winning student can play the next student up, in a round robin, if necessary. If there is no winner in the tic-tac-toe game, the teacher should move on to another group of two students. Overall, this is a more effective game to play in classes of ten or fewer students, because this still

Marketing Strategy Assignment Example | Topics and Well Written Essays - 3000 words

Marketing Strategy - Assignment Example Taking cue from international brand, Tesco, along with its various marketing and global expansion strategies over the years, the report will evaluate the various marketing strategies, which are essential for success of a retail firm while entering into a new or foreign market. The report will also throw light on concepts such as, localisation. A situational analysis of the Turkish retail environment will be conducted, which will help in understanding Tesco’s current operations and future in Turkish market. The development of retail sector is based on democratization of the consumption of consumer, which is a result of the development of low price model of economies. This model is founded on value offerings oriented towards low pricing ranges. For effective implementation, this model relies on controlled distribution costs and increasing the circulation speed. Marketing is a critical factor in this category of business and expectations of customers are the major focus, in order to locate the lowest possible prices. However, marketing tends to merge with communication and advertisement in order to bring out the best results out of veracious models and theories adopted by the business. With the increasing success of the retail sector, companies have now started to realize the need for change in their strategies and tactics, majorly by understanding and adapting the evolution in customers’ behaviour as well as expectations (Holt, Quelch and Taylor, 2004). Securing a consumers’ loyalty and increasing their wallet share have taken an important place in the strategies of these retail companies; rather than just acquiring new customers. A sharpening competition among retail brands has prompted these retail firms in paying more attention to their marketing activities. The integrated marketing communication, adopted by many big retail brands, such as, Tesco and Walmart, has given

Fashion History Essay Example for Free

Fashion History Essay A fancy handbag, stylish footwear, shimmering jewellery and a designer dress of substandard quality sell at fantastic prices. Now beauty salons and slimming centers the landmarks of fashionable world are frequented by a large clientele at great expenses even in smaller towns. It seems the inbred urge of the man to appear graceful is awakening from the slumber. But the craze for fashion has also opened new avenues for expansion of small scale industries product fancy articles for beauty aids are now growing and shaping up as big industries. They provide employment to thousands of youth directly or indirectly. Courses based on fashion designing and decoration have now become a popular and recognized commercial education in the country. Ever changing fashion is welcome features but living in fashion and style is a symbol of lively society. Fashions breaking the barriers of decency and decoration are full risks and lead to moral chaos. We must be aware of that fashion adds only to our external beauty which is skin deep and transient whereas moral beauty is lasting and sublime. True beauty lies in cleaning ourselves from within and is attained by practicing truth and piety love and sacrifice in our lives but in the avalanche of ever changing fashions, all that matters is ostentatious show with the aid of modem cosmetics and beauty aids, latest dresses etc. And this is eating into our great noble values. True, beauty needs no ornaments or fashion aids. My lord I may be beautiful from within in this age of fashion.

Extinction of Dinosaurs due to Asteroid Impact Essay -- Exploratory Es

Extinction of Dinosaurs due to Asteroid Impact Nobody knows for sure exactly how the dinosaurs became extinct. However scientists have speculated for decades about possible events that caused the dinosaurs to die out. Possibilities range from asteroids, to volcanoes, to climate changes. One of the more popular or well-known extinction theories involves the belief that an asteroid struck the Earth, causing devastating effects, and triggering mass extinctions around the end of the Cretaceous period. The asteroid impact extinction theory began in 1980 with Luis and Walter Alvarez, a father and son team. They theorized that an asteroid struck the Earth at the close of the Cretaceous period, causing devastating effects and mass extinctions (Botzer 2004). Then, in the early 1990s, Alan Hildebrand, an associate professor at the University of Calgary, discovered the Chicxulub crater on the Yucatan peninsula in Mexico. This crater was 186 miles in diameter and six miles deep, and it was created when an asteroid hit the Earth approximately sixty-five million years ago. This asteroid is said to have strike the Earth with a force of 100 million to 300 million megatons of TNT (Recer 1993). With the discovery of the crater came the theory that this particular asteroid killed the dinosaurs and caused other mass extinctions. It was believed that the impact of the asteroid increased temperatures to above 20,000 degrees, sent massive tidal waves and earthquakes across the Earth, and fill ed the atmosphere with dust and chemicals, which blocked the sun. It was then hypothesized that the blocking of the sun led to drastic climate changes, allowing the Earth to cool, and creating a climate too cold for the warm-blooded dinosaurs (Re... ...me 300,000 years after the impact. We still don’t know for sure what happened to the dinosaurs, and there is a possibility that we never will know. However, several signs indicate that the Chicxulub asteroid probably created conditions that begin the decline of the dinosaurs. This was most likely followed by a second large impact, or several smaller impacts that caused drastic changes in the environment and resulted in the mass extinction. Works Cited Botzer, Angela. â€Å"That Asteroid Didn’t Kill Dinosaurs, Study Says.† National Geographic News. 9 Mar 2004. 31 Mar 2004 http://news.nationalgeographic.com/news Keller, Gerta, et al. â€Å"Chicxulub Impact Predates the K-T Boundary Mass Extinction.† PNAS Online. 2 Mar 2004. 5 Apr. 2004 http://www.pnas.org/cgi Recer, Paul. â€Å"Crater Theory: Big Space Rock Did in Dinosaurs.† Times 17 Sep. 1993: National.

An Examination of Bias in Focus on the Family’s Website Essay

Part of the problem with criticizing religion is the fact that any attempt to criticize yields a label of bigotry. In other words, if you question or criticize a religious movement the response is that the person putting forth the criticism is an anti-Semite or anti-Christian. While in many cases, this is true, but in other cases, that is simply not the case. But, because of the emotional attachment to religious beliefs – particularly the beliefs of individuals who hold strong fundamentalist beliefs – any attempt to question is met with anger. This is even when the issue being questioned is something that is pure opinion open to debate and not a fact that is set in stone. Dr. James Dobson, the head of the Evangelical group Focus on the Family, is hardly an unintelligent man. He is a published author and charismatic leader of a large denomination of conservative Christian groups. While there will be those who are dismissive of Christian conservative merely because they are, well, Christian conservatives, is childish. Criticism about political or sociological issues derived from bias and opinion, however, is fair game for debate. One such issue of contention on the website involves the assertion that homosexuality can be â€Å"cured. † To this regard, the website states: Homosexuality is more likely to be related to one or more of the following: (1) confusion of role models seen in parents, including, but not limited to, a dominant mother and a weak or absent father; (2) serious family dysfunction that wounds and damages the child; (3) early sexual abuse; (4) the influence of an older homosexual during a critical period of adolescence; (5) conscious choice and cultivation; and/or (6) homosexual experimentation, such as mutual masturbatory activity, by boys in early adolescence. How do these and other forces interplay in individual circumstances? I don’t know. I don’t think anyone knows. An Examination of Bias in Focus on the Family’s Website Page 2 On the other hand, I am certain that homosexuality does not result from irresistible genetic influences, as some would have us believe. (Dobson) To say these statements are biased and agenda driven would be an understatement. While Dobson is entitled to his opinions, the operative word here is opinion. The statements made in that excerpt are presented as fact when, in reality, there is no empirical proof that they are factual. Instead, the statements are presented to provide circular logic credibility to a socio-political agenda. Now, it is well within Dobson’s right to present his side of the issue. However, it is not a balanced examination of the issue and it contradicts a wealth of psychiatric and sociological study on the issue. Because of this, there is a great deal of intellectual dishonesty in these statements of homosexuality. A more proper examination would present Dobson’s opinion while acknowledging there are other opinions on the matter from professional fields, include a quote from a peer reviewed journal on the subject and then provide a link to a website that provides an alternate point of view. This does not mean that Dobson should abandon his beliefs nor should Focus on the Family retract their statements, but the organization would be far better served presenting an unbiased look at the subject and avoid presenting opinion as fact. Bibliography Focus on the Family. (2007) http://listen. family. org/daily/A000000198. cfm Dobson, James. (2006) â€Å"Do You Believe Homosexuality is Inherited. † Retrieved 4 February 2007. http://family. custhelp. com/ cgi-bin/family. cfg/php/enduser/std_alp. php? p_sid=6n4Jcohi

Challenging Obstacles for Immigrants

Many people migrate to the USA for several reasons, to get better life. As we all know the USA is highly developed economically and technologically, and it can become a different world to most immigrants. Thus, immigrants face various challenges during the first and second year of their entrance in to the USA. Among the challenges, language, getting a job and culture are common for most of immigrants. The first challenge for immigrants is the language barrier. Since English is the second or third language for most immigrants, they face a lot of problems to communicate. Although, immigrants have some knowledge of English, the pronunciation of most words is different. So they can’t understand and communicate very easily. Furthermore, the accent of native speakers, Mexicans, Black Americans, and Chinese is different. This complicates the communication and creates stress for immigrants. For example, I came to the USA recently. I have some knowledge of English, but when I took my kids to the hospitals, go to shopping, and even when I was applying to this college, I found people who use different pronunciation and accent. Sometimes, I heard 50% to 90% of what people said and likewise they were not able to understand me, even though I was talking in English. As a result, â€Å"I’m sorry†, â€Å"say again†, â€Å"pardon† were my day to day words I used and heard for a couple of months. Therefore, language is the first big challenge that all immigrants face. The second challenging obstacle for immigrants is getting a job. Since language is a problem for immigrants, most of them failed in job interviews. Even though they are educated and professionals in their home country, it costs and takes time for their education to be accepted here. Thus, getting a job is tough. Especially now, following the economic crisis of the world, there are many layoffs and getting a job is like a miracle to most immigrants. In addition, the jobs available for immigrants are manual labor jobs that are tiresome. These jobs may also have fewer hours and surely have minimum pay. Therefore, immigrants will be forced to find another tiresome job to cover their living expenses. But getting another job is another worry for immigrants. Here I am going to give my husband’s experiences. As soon as we reached America and got our social security numbers, my husband tried to search and apply for jobs. After several months and trial, he got a part time job with minimum wage. His salary is not enough to cover our expenses, and now he is searching another job, but none has been found. Thus, following the language barrier, getting a job is a big challenging to immigrants. Culture is the third challenge that immigrants face here. Immigrants have their own cultures and living styles in their home country. The culture of dressing, talking, eating, social life etc†¦ is different here from immigrants’ home country. For example, here man and woman can kiss on the lips anywhere, but this is taboo in my country, Ethiopia. Another example is the way girls’ dress, here girls can wear whatever they like such as shorts and mini dresses. However, in my country, this is not accepted and girls should wear clothes that don’t expose their body. Thus, they should wear shorts and dresses which are below to their knees. The other thing here people eat their food anywhere; they can even eat walking on the street. However, in my country people, especially girls, cannot walk on the street while eating or drinking. There are several customs here that are counted as taboo in my culture. Therefore, the cultural differences make immigrants to be confused and shocked until they accustomed to it. As time passes, immigrants will manage and defeat the obstacles through several exposures and practice. Then, after passing through the obstacles, immigrants will enjoy a better life and even be in higher positions like senators, vice-presidents and also president of America.

U.S.-Soviet Relations essays

U.S.-Soviet Relations essays The beginning of the Cold War between U.S. and Russia caused a major polarization across the World. Countries like Korea, Vietnam and Germany were split in half-one half would be democratic and the other communist. The fight for the sphere of influence became mmore of a territorial fight, often times a small war. The Korean War (1950-1953) was one of the confrontations which infuenced the relation between the 2 superpowers. All the fights had their echos at home. The Red Scare became bigger than ever during this period and people like Joseph McCarthy spoke out loud the fears of all Americans and transformed the political scene in U.S. . But McCarthyism did not influence the relations between the two countries as much as it influenced the view and attitude toward communism of the Americans. Afer Japan was defeated in 1945, Korea was divided at the 38th parallel. North of the political border would be Soviet territory (People's Democratic Republic) and South would be U.S. territory(Republic of Korea). In 1950 North Korea invaded South Korea. Truman considered it a Soviet-directed attack more than an internal Korean matter; he never doubted that Stalin saw Korea as a test of the containment policy and U.S. will, despite conflicting evidence. Truman declared that not intervening in Korea would be a big mistake because it could spread through Europe and Asia. He also wanted to prove in the area of politics that the Democrats would fight communism. Truman sent General MacArthur as a commander of American forces in Korea. After futile battles MacArthur proposed to use the A-Bomb an even to help rebels in China to overthrow the communist government. But Truman answered that they were trying to prevent a war, not to start one. He was afraid that the Soviet union would take adv antage of American involvement in Asia and attack Western strongholds in Europe. An armistice was set in 1953 to cease fire. This conflict ...

Chain of Stores in Different Demographic Set-ups Case Study

Chain of Stores in Different Demographic Set-ups - Case Study Example As the paper highlights the issue on product specialization revolved around the products with high direct production costs (DPC). Fragile goods such as charcoal had high handling costs amounting to a DPC value of $0.37. Disposable diapers also held high DPC values of $0.70. These presented a problem with bulkiness. The varieties of the diapers, For example, kept changing, and that caused inconveniences in constant resetting of the shelf fixtures. This discussion declares that the display of products formed another area of focus. In this element, the study focused on the product and category sales per foot of the shelf space. The approach provided evidence that alcoholic beverages and cosmetics took considerable shelf space but generated considerably low in the returns. Alcoholic beverages performed poorly at $7.45 per feet while cosmetics performed even worse at $0.69 per feet of shelf space. Though they presented low returns, these products occupied considerable shelf space. The alcoholic beverages took a total of 513.3 feet of shelf space with only weekly sales of $3,823.73. Carbonated beverages, on the other hand, recorded almost triple in weekly sales to that of the alcoholic beverages ($10,003.92) but occupied shelf space of 339.7 ft. Cereals and other breakfast foods also occupied considerably little linear space, 166.6ft, regardless of the higher sales compared to the alcoholic beverages. In the non-edible grocery sect ion, soaps and detergents took the largest share in the shelf space allocated. The weekly dollar sales were $9187.17 compared to paper products (shelf space of 338.3ft and weekly dollar sales of $8483), and cigarettes/tobacco products, which had weekly sales of $11024.62, with a linear shelf space of 156.6 ft.

Living Arrangments Essay Example | Topics and Well Written Essays - 500 words

Living Arrangments - Essay Example The general living conditions of each type of housing must be taken into account if a college student wants to be successful in achieving his or her goal. It cannot be argued that living in a single apartment, with no one around to disturb you or interfere with your plans is a desirable situation. The peace and quiet of your own space cannot be measured in concrete terms and being master of your own time and space is an important psychological element of growing up. It is often a necessary step in distancing yourself from parents who are accustomed to treating you as a small child rather than recognizing your adult status. There is also no one inviting their friends over and making loud noise during these times as might happen when living with friends. However, there is also no one around to do your laundry for you or to cook dinner for you and make sure there is food in the house, all of which is normally taken care of when you live at home. There is no one around either to help you with homework or difficulties or to keep you company when you’re alone as there would be with a number of roommates. With no clear cut answers provided in considering living conditions, it is also necessary to consider the likelihood of your college success in terms of available study time. When you live on your own in a single apartment, you have all the time you could want to study in peace and quiet. There are no parents coming in to bother you with other responsibilities and no friends bringing over other friends to encourage you to push the books aside. At the same time, parents are often helpful in encouraging you to take time to study, which can make the difference between college success and college failure and friends can sometimes be very helpful in understanding work that you just don’t get. In considering both living conditions and study time, the concept of support emerges as an