Chem 101 Lab Report 2 Essay

Mixtures are made up of substances or components. If the mixture is fairly uniform in composition, properties, and its overall appearance, it is homogenous. If the component parts are clearly separated, it is heterogeneous. In order to identify the components in a mixture, methods must be used to sort out the components. However, the same methods will not work for sorting all substances. Four different processes would be employed to sort soluble and insoluble components in the following experiment. Introduction Matter that people encounter in everyday life consists of mixtures of different substances. Mixtures are combinations of two or more substances in which each substance retains its own chemical identity and therefore the original properties are maintained. The substances making up a mixture are called its components. According to our General Chemistry book, there are two types of mixtures; homogeneous and heterogeneous. Homogeneous mixtures are those that are uniform in composition, properties, and appearance throughout. Heterogeneous mixtures do not have the same composition, properties and appearance. Mixtures are characterized by two different properties: each of the substances in the mixture retains its chemical identity and mixtures are separable into these components by physical means, from heating, freezing, drying, etc. If one of the substances in a mixture exceeds the amounts of the other substances in the mixture you call it an impure substance and the other substances in th e mixture are impurities. The preparation of compounds usually involves their separation or isolation from reactants or other impurities. The separation of the components of mixtures is based upon the fact that each component has different physical properties. The components of mixtures are always pure substances, either compounds or elements and each pure substance will possess a unique set of properties. Similarly, every crystal of a pure substance melts at a specific temperature and a given pressure, and every pure substance boils at a specific temperature and a given pressure. There are four different methods of separation depending upon differences in physical properties. They are decantation, filtration, extraction, sublimation. In decantation, a liquid is separated from a solid by gently pouring the liquid from the solid so the only the solid remains in the container. Filtration is the process of separating a solid from a liquid by using a porous substance (a filter). Filtration allows the liquid but not the solid to pass through, again, leaving behind the insoluble substance. Extraction separates a substance from a mixture by choosing to dissolve that substance in a suitable solvent (usually water). Sublimation happens when a solid passes directly to the gaseous state and back to the solid state without passing through the intermediary liquid state. Material and Methods ï‚ · Evaporating Dish ï‚ · Beaker ï‚ · 3.0 Grams of mixture (NH4Cl – ammonium chloride, NaCl – sodium chloride, SiO2 – silicon dioxide) ï‚ · Heat plate ï‚ · Balance ï‚ · Oven ï‚ · Stirring rod ï‚ · 15 mL water x 2 = 30 mL water 1. Obtain mass of evaporating dish. 2. Add 3.0 grams of mixture (NH4Cl – ammonium chloride, NaCl – sodium chloride, SiO2 – silicon dioxide) to the evaporating dish and weigh to obtain mass of evaporating dish and sample mixture. 3. Subtract mass of evaporating dish from mass of original sample to get mass of original sample. 4. Place dish with sample onto heat plate to sublime the NH4Cl. 5. Remove from heat to cool mixture then weigh again. The difference in mass of evaporating dish and sample prior to heating and after heating represents the amount of NH4Cl in the mixture. 6. Obtain mass of beaker using the balance. 7. Add 15 mL of H20 to the mixture in the evaporating dish and stir gently 8. Decant the liquid into the beaker making sure not to transfer any of the solid into the beaker. 9. Add another 15 mL of H20 to the mixture in the evaporating dish and stir gently. Decant the liquid again into the beaker making sure not to transfer any of the solid into the beaker to extract NaCl. 10. Place beaker with sodium chloride solution onto heat plate and heat until water evaporates. Remove from heat and allow to cool. Weigh beaker. Difference between this weight and the weight of the empty beaker is the amount of NaCL in the mixture. 11. Take evaporating dish with SiO4 and heat until dry in oven. Once dry, remove evaporating dish from oven and allow to cool. Obtain the mass of SiO2 by weighting the evaporating dish with cooled mixture and subtracting mass of empty evaporating dish obtained earlier. 12. Find percent of NH4Cl, NaCl, and SiO2 in mixture by taking mass of each substance and dividing by the mass of the original sample. Results: Separation of the Components of a Mixture A. Mass of Evaporating Dish and Original Sample 41.606 g Mass of evaporating dish 38.859 g Mass of original sample 2.747 g Mass of evaporating dish after subliming NH4Cl 41.466 g Mass of NH4Cl 0.14 g Percent of NH4Cl 5.096 % % NH4Cl = 0.14 g / 2.747 g * 100% = 5.096 % B. Mass of Evaporating Dish, Watch Glass and NaCl 106.521 g Mass of evaporating dish and beaker 105.214 g Mass of NaCl 1.307 g Percent of NaCl 45.32 % % NaCl = 1.307 g / 2.747 g * 100% = 45.32 % C. Mass of Evaporating Dish and SiO2 40.104 g Mass of evaporating dish 38.859 g Mass of SiO2 1.245 g Percent of SiO2 45.322 % % SiO2 = 1.245 g / 2.747 g * 100% = 45.322 % D. Mass of Original Sample 2.747 g Mass of determined (NH4Cl + NaCl + SiO2) 2.692 g Differences in these weights 0.055 g Percent recovery of matter 97.997 % % recovery of matter = 2.692g /2.747g = 97.997 % Account for our errors about 2% Discussion The first step in the experiment required using the oven to heat the mixture, with ammonium chloride, sodium chloride, and silicon dioxide in the evaporating dish, until â€Å"white fumes were no longer form[ed],† according to the lab description. The goal was to sublimate the ammonium chloride, as it is not water soluble. It took about fifteen minutes to sublimate the NH4Cl. The dish had to cool as well when it came out of the oven. The mass of the dish contents were weighed and subtracted from the mass off the starting mass of the dish and the original mixture. The result was the loss of NH4Cl. Errors could have resulted from incorrectly weighing the original and ending samples. If ample time was not given to the sublimating process, NH4Cl may not have completely left the dish, the weight would not just include the mass of the other two substances. The next stage required careful decantation and stirring to remove only the liquid into a separate dish. The goal was to leave b ehind the insoluble substance, sand, and pour off the soluble NaCl. It was possible to accidentally remove particles of sand into the solution, which would influence the mass calculation of the two dishes. If stirring was not rigorous enough and water was not repeatedly added to sort out the sand from the liquid, there was a potential for sand staying behind as well. The final stage was to use the heating unit to evaporate the water from the solution to leave behind NaCl. At the same time, the heating unit was used to dry the sodium chloride in another dish. A calculation was made between the mass of the empty evaporating dish and the watch glass to reveal the mass of NaCl. Errors at this stage probably resulted from inaccurate readings on the scale or not drying the samples completely. The final stage of the experiment was to isolate the sand and calculate its mass. By this late stage, any errors in measurement, timing and calculations would have trickled down to the final remaining substance. The percentage of accuracy of the three components in the experiment should total 99%. If the percentage was less than that, â€Å"you have been sloppy† according to the lab manual. Conclusion In this experiment, it became apparent that what appears to be a simple mixture of elements is really more complicated. Heterogeneous mixtures may appear to be random collections of single substances, but when they are sorted into their components, the homogeneous elements can be observed. This was the case with this experiment. The original mixture had three substances: NaCl, NH4Cl, and SiO2. By using four methods, decantation, filtration, extraction, and sublimation, the separate components in the mixture could be isolated and weighed. If proper techniques in weighing, and using the four methods of sorting were observed and applied, the result would be three separated substances and calculations that matched those substances. The final calculation confirmed that our three substances, when sorted out, would all combine to weigh something close to the original mixture. The margin of error was within 2% References Book: 1.Ebbing, Darrel, D.; Gammon, Steven D. General Chemistry. 9th ed. Belmont, CA: Brooks/Cole Cenage Learning; 2009. 2. Beran, JA; Beran,JoAllen: Laboratory Manual for Principles of General Chemistry. 8th ed. Hoboken, NJ. Jon Wiley & Sons, Inc; 2009. 3.Katz, John C.; Treichel, Paul M.; Townsend, John. Chemistry and Chemical Reactivity. Belmont, CA: Cengage Learning, Inc.; 2009. 4.Somervill, Barbara A. Mass and Weight. Chicago, IL: Capstone Global Library, Ltd.; 2010. Electronic book: Chem Wiki:The Dynamic Chemistry Textbook. http://chemwiki.ucdavis.edu/Analytical-chemistry-html. Accessed August 29, 2013. Website: 1.Measuring Mass-Examples. http://www.harpercollege.edu/tm-ps/chm/100/dgodambe/the disk/labtech/mass2.html. 2.Jefferson Lab. http://education.jlab.org/qa/mass-09.html.

Week Lesson

Chamberlain College of Nursing. Transcript Organization and Time Management Starting a new venture can be exciting and challenging. You're pleased to begin a new phase In your life, yet concerned about how you'll handle all of the new responsibilities. You may already have a Job, family. And other commitments, and now you've added school to the list. Are there enough hours in the day?One way to answer this question is to take a serious look at how much time you Penn working, sleeping, caring for your family, and engaging in outside activities. Ask yourself what could be consolidated, eliminated, or delegated to someone else to allow you more time for school. The Question As a nurse, you already have many organizational and time management skills that you put to use every day in your job. Think about your skills, and then click to view the answer.Your Answer The Expert Says If you are a staff nurse, each morning you check the assignment board to see which tenants you'll care for that day, gather your report sheets, and enter the conference room. You'll listen to reports focusing on the Important issues and Jotting down notes to help you remember the Items later In the day. Chances are that you have a system for taking report that even involves writing the important issues in certain locations on your report sheet for easy retrieval later. As you leave the conference room, you're thinking about meds due in the next hour and organizing your medication cart.You aka rounds on your patients and do assessments next. Whether you use a written list or a mental one, you've already determined what Important events need to be taken care of during your shift. Who Is going to surgery and needs the preoperative checklist completed? Who is going home and needs discharge teaching and confirmation of transportation? Who is a flirt-day posts patient and needs the dressing changed and to be up in a chair? Who needs blood? On top of all that, you're prepared for the unexpected admi ssions or emergencies.You know who your aide is for the day and what you'll be delegating to that person. You then remember that you have a staff meeting at 1 p. M. , so you'll need to plan your schedule a little differently today to make time to attend that Important meeting. The day doesn't end when you're done at work. Tonight is your son's hockey game, so you'll be there after work. See? You already have much experience organizing and managing your time! How can you use all those great skills to promote success as an online student? Compare

Is Money the Most Important Thing? Essay

Nowadays, we are living in a world where everything turns around money and luxury. People do not realize that we can find more things which are more important for our lives and happiness. Some years ago, other important things were to spend quality time with the family, talk to each other about important thing in order to be always together and be informed about what is happening to the most important people in the society: your family. To different people money is important in many ways. Money is used to do a lot, you use it to buy a house so you have somewhere to live instead of living under a bridge, you use it to keep your car running properly, and without money a lot of people wouldn’t be happy. Without money people cannot live healthy. You need money to buy food, clothing, and personal hygiene products. To me money is less important as long as I have enough to get food for my family, a roof over my head, clothing for my family and myself, power to my house, and money to ride the bus. I am completely happy and that is what is important about money to me. see more:muet essay It would be nice to have some extra here and there but as long as my family and I can survive that is all that matter. How would you pay your bills if you didn’t have money? How would sick children get the help they need without money? Both of these questions are questions that have been a big deal in my life. The answer to each is you would be able to. Even if you didn’t have money and you needed assistant – that still involves someone donating the money. Money is an important aspect to everyone in this stuff called life. Then again to other people money might be important in other ways. It all depends on who we are talking about when we ask the question â€Å"How important is money?† Without money we wouldn’t be able to go to school and prepare for life or get college degrees and further our educations. We wouldn’t be able to pay for medications that help heal us of any diseases or pain. I do subscribe to the notion that money isn’t everything but I also believe that it is a major, critical facet of life today. Some people would like to have money, not to be a rich  person, but to have the minimum things to live worthily. Even if money is important to have a good life and without it we cannot do anything, it is not the most important thing. There are other characteristics that are more important in people, such as, what other people are inside themselves. Also, the idea of getting power because of having money is an actual problem in our societies, because many people grow up with that idea, and the more money you have, the more money you want to get. This action creates selfish people who think that all their problems can be solved thanks to money but in the real life, things are very far from this concept of life. People from real life have to fight for getting things, for being successful and for being happy. So it is important to teach people while they are growing up the real value of the things that are around themselves and how they can face money problems and the main meaning of this overvalued component in the present world. None can deny the importance of money in life. However, whether or not it is actually the only thing people are interested in today is much of controversy. Some people believe that money ca n buy everything when the others assert that it cannot. From my point of view, there are a lot of achievements rather than money although I can live without it. It seems to be meaningless for me to come in for a well-to-do life without endeavor for any reason. Perhaps, for me, money is not able to buy happiness. Not only has the value of money changed, but also its importance. The importance of money has become so essential for life, that you could not survive without it. You could not even buy something to eat. You would end up being a poor homeless person. Even if you try harmonizing with the nature to survive, it would be almost impossible nowadays, except if you are living in a tribe. Tribes have learned to live naturally and have adapted to the nature, while industrial countries have invented artificial stuff for everything. Money is one of the most important things in our lives. Even if we haven’t noticed yet, living without it would be literally inconceivable. Money is very important because of its value in daily life. Without money, we do not have accommodation, food, and clothes which are considered the basic necessities. In most developing countries, children cannot go to school when their parents do not have money. They have to do manual works in bad conditions and university is definitely a far-away dream. Money seems to be the most important issue for those. For those of the middle class, money  gives a comfortable life. The most important advantage of being rich is that your health will be protected well when you have a lot of money. It is true for every social system. A millionaire can pay a lot of money for the best hospital, best doctor and best technology while a poor unemployed woman mainly depend on social subsidies with cheapest medicines. If you do not have enough money, please wait without any requirements. Life has never been equal, particularly between the rich and the poor in the society. Money has become a very crucial aspect of living. It allows us to provide ourselves with the basic needs of life as well as forcing us to make realistic choices and place priority on our needs before our wants. But money has changed society a lot. The people who do not make too much, are not t oo happy. However, those who have money are often unhappy. They can never get enough. Everything that they have needs to be updated and when they get the item it’s already old so they end up replacing it. For this reason the rich never get to sit back and enjoy what they have. They are too busy buying. For most people in our modern world, money is the first thing, and sometimes the only thing that measures success in their life. Money can buy power. Money can buy fame. Money can buy time. Sometimes money can even buy a life. Thus money has become the first common goal for everybody. However, there is something else that can be the measurement of success in life. For example, the common goal in people’s life is to be peaceful and happy. It might be having a warm family and children, having lots of friends or maybe just having someone who truly loves you. Being the richest man in the world does not mean you are the happiest man in the world, although money can buy you happiness sometimes, but not always. If we could all appreciat e the way life is, the fun, and the beauty I think the world would be better. If people weren’t power hungry maybe we’d have a lesser demand for money. Those people who is money hungry and power hungry need to relax. Money can’t buy you happiness. These individuals need to understand that.

The Social, Economic, Technological and Cultural Impact of Video Games Essay

The Social, Economic, Technological and Cultural Impact of Video Games on True Art - Essay Example Entertainment is one of the core recreational activities in the world today. Previously, many people could be seen filling movie theatres to the brim in their endeavor to unwind and gain infotainment through cinemas. Cinemas illustrated real people images devoid of simulation and interactive participation of the audience. This is turning out to be a past practice as the world is embracing a new digital age brought about by the emergence of various computer applications such as the video games (Nichols, et al 133). This venture is finding its way in the lives of many young generation peers who are finding solace in it away from the hard economic, social and cultural society practices which many consider to be boring and outdated. Notably, the youth are the most affected by the video games industry with most of them spending to the last penny to attain the modern and latest video games. This is in their push to achieve an orchestrated physiological and emotional satisfaction as though were the true characters in the dramatic competition illustrated by the video game (Jenkins 4). ... Thesis Globally, story telling and interactivity forms the core concern of a true art. Every audience will be attracted to an art that illustrates a well organized and vividly analyzed and sequential story. It is every ones concern to follow a narrative that will develop to a given plot with ultimate objectives to be attained. Every masterpiece must achieve a great sense of humor and at the same time provoke our inquisitiveness, pleasure and critically trigger off the desire to explore further (Jenkins 2). An interactive tale which prompts the curious participation of the audience gives a more gratification as they simulate the characters to attain a conceived objective. Video games are designed to ignite the imagination of the perceived audience captivating them on heroic quests to new extraordinary and fantasy worlds (Jenkins 3). True art balances the economic, social and cultural status of the society as it attains its infotainment objective. It creates various opportunities that will enhance the economic gain of the audience and the characters presenters, with an equal maintenance of the societal social and cultural values. The purpose of this study is to investigate the social, economic and cultural factors of video games that influence true art. The report will provide its findings on the impact of the video games being developed in the world today to the true art. Literature Review Corneliussen, & Walker (114) says that there is a continuing interest in the study of the forces that influence the impact of video games on the true art particularly that which can be harnessed to provide a clear conformity to the objectives of a true art. The ideas that came in the early 1970s explicitly depicted video games as a killer of the true art illustratively

Struggle with Self-Image Research Paper Example | Topics and Well Written Essays - 1000 words

Struggle with Self-Image - Research Paper Example There are certain norms in the society that dictate how people should represent themselves and people portray these images instead of a person’s personal image. This paper will discuss the struggles with self image, highlighting the conflicts between man and himself, and man and the society as seen in Walker and Orwell’s essays. The essay, â€Å"beauty: when the other dancer is the self†, is about self realization and appreciating one’s own potentials. It’s a detailed account about how the author struggled with her self- image after a childhood accident that left one of her eyes disfigured. Orwell’s essay is about the author’s experience in a British ruled Burma where he was stationed as a young inexperienced soldier. While there he had to kill an elephant that had run rampant, this triggered some ethical conflicts within him (Gausel and Leach 7). In the beginning, when Walker was young she was convinced that beauty came from what the eye meets. At the age of two she is very confident in her beauty and she says â€Å"take me daddy, am the prettiest†. The way she describes her dress, she feels that everyone is admiring her beauty. She goes ahead and states that it was not her dress that they admired but it is her spirit that they adore. This shows the self love that Alice for herself which portrays a positive image. Loving yourself portrays positive attributes about you in other people’s eyes. To begin with, self image is all on the mind. Walker’s shallow perception of beauty was short lived. After the accident she could no longer maintain the former definition. She was able to see, but she could not perceive. Little did she know that all it takes is a positive self image; that the loss of her eye does not mean that she lost her beauty. What bothered her was how the society viewed her after the accident judging from their negative glances. According to Bates (3), Walker believed that all they saw was a glob of whitish tissue, a hideous cataract. Body image is part of self image. This includes more than what we look like or how other people view us. It is how we think, perceive or react about our physical attributes. Influence of our family, peers and the society affect our body image and consequently our self image. For instance, Walker had to be taken away to live with her grandparents to avoid ridicules from other children. Her parents did not stop to think if it would affect Alice’s self image (Bates 4). A positive body image contributes to improved psychological adjustments. This is exactly what happened when Walker’s daughter said she saw a world in her eye. In her little mind her mother was beautiful and her eye was unique. This gave Walker a wakeup call and she realized she was the one to blame for the anger she felt for all those years. Orwell on the other hand begins the essay by claiming his perception on the British imperialism. He claims how evi l they are yet he is a British soldier himself. This is the first indication of his struggle with self image. Deep inside he didn’t want to gun down the elephant. He said his ultimate decision was to avoid looking bad in front of villagers; that gave him a degree of shame. This clarify the issue that self image is grounded in social relations regulated by moral standards. If self image is inherently social, then improving it results in improved social relations. It is this shame that makes him to be more concerned about how the villagers perceive him (Leary & Ashley 9). He

Textiles - Silk Research Paper Example | Topics and Well Written Essays - 1250 words

Textiles - Silk - Research Paper Example Ancient Chinese first developed silk fabric, with the earliest examples dating back to 3500 BC. Legend gives credit to a Chinese empress, Hsi-Ling-Shih, Lei-Tzu for discovering silk. Legend has it that she was in her garden sipping tea when a cocoon fell into the cup and since the tea was hot; the long silk strand was loosened. Apparently, she later raised silkworms and made a loom which she used to make silk fabrics. Originally, silks were reserved for the Chinese Kings for their use and presents to others. They later spread gradually in the Chinese culture and traded socially and geographically in Asia. It became a luxury fabric in the areas with access to Chinese merchants due to its lusture and texture. The demand for silk skyrocketed and became a staple of international trade (Philippa, 1993). There is evidence of the trade in silk from silk found in the hair of a 21st dynasty mummy, c.1070 BC in Egypt. This trade reached as far as the Middle East, the Indian subcontinent, North Africa, and Europe. The trade was very extensive such that the main trade route between Asia and Europe came to be named the Silk Road. The Chinese emperors tried to keep sericulture knowledge so as to maintain a monopoly. Nonetheless, it reached Korea by 200 BC, ancient Khotan in around 100 AD, and India around AD 140. However, Chinese silk was the most sought-after and lucrative luxury item. It traded across the Asian and European continents with many civilizations like the ancient Persians economically benefiting from the trade. Today, the major producers of silk are India (14%) and China (54%). Japan is the leading consumer of Silk (Sara, 2007). Silk moths lay their eggs which later hatch to caterpillars (silkworms). The caterpillars are fed with fresh mulberry leaves. Thirty five days later, they are 10,000 times heavier compared to when hatched. A straw frame is put over the tray with caterpillars. Each caterpillar spins a cocoon when it moves its head in a certain pattern. L iquid silk is produced by two glands which force it through the head openings called spinnerets. It is coated with sericin, a protective water-soluble gum which solidifies on contact with air. Between 2–3 days, a caterpillar can spin about a mile of filament, encasing itself in a complete cocoon. Sadly, silk farmers kill most of the caterpillars by heat. Only a few are left to metamorphose into moths which breed a new generation of caterpillars. The cocoons are harvested and soaked into boiling water for the sericin which holds the silk fibers in a cocoon to soften. The fibers are unwound to make a continuous thread. Between three to ten threads are spun together forming a single silk thread (Sara, 2007). Sericulture refers to the raw production of silk through raising silkworms. Silkworm production relies on various environmental elements which affect silk production feasibility in many parts of the world. Since the harvesting process kills the larvae, animal rights and welf are activists have criticized the sericulture process. This led to Mohandas Gandhi promoting cotton spinning machines. In addition, he promoted Ahimsa silk (wild silk) made from the cocoons of semi-wild and wild silk moths. It is promoted in Southern India catering for people who do not prefer silk produced through killing of silkworms. The PETA organization has also campaigned against silk (Sara, 2007). Silk from silkworms is composed of two major proteins, fibroin and sericin.

International Advertising WPP's Digital Push Essay

International Advertising WPP's Digital Push - Essay Example In order to ensure sustenance in today's globalized scenario, the advertising industries need to redesign, reframe and refurbish their approach to the overall concept of advertising. The competition in the contemporary advertising industry is not so much about scoring over one's rivals, but more about assuring a timely transition from traditional business models to E-business models. 1. Survival in the Contemporary Advertising Scenario is a Fast-paced and Perpetual Process: The traditional advertising business was more of a predictable and a relatively lethargic system that resorted to and adapted to change at a slow pace. However, the contemporary advertising industry being dependent on internet and information technology is a perpetually evolving and a continually altering business. The advertising professionals ought to be always on their toes to benefit from and incorporate the upcoming opportunities unleashed by technological changes. 2. 2. Resistance to Change is Death: Considering the ongoing shift towards online approaches, the advertising professionals need to embrace digital technology as not one another option, but the ultimate way the businesses will conduct themselves. This calls for a marked shift in the mindset and individual perceptions. With a bulk of revenues coming from Web marketing, resistance to change means a sure death. 3. Don't Expect Well Defined and Clear Cut Adversaries and Friends: The digitalized advertising industry of today is not a battle ground, but a global market that requires an amorphous approach that can make way for a simultaneous collaboration and competition between the key players, based on the identification of opportunities and ensuing challenges (Steel 2009). 4. Do not Expect Ignorant Customers: The contemporary advertising industry will have to grapple with the customers who are well informed and cognizant of their requirements. The customers today are immaculately choosy about the advertising solutions that can serve their needs. 5. Synergy is the Name of the Game: Big advertising companies should visualize themselves as a fluid talent pool that can exploit the abilities and resources scattered across the organizations to assemble compatible and seamless virtual teams (Koncept Analytics 2007). 6. Do Not Worry About who Gets the Credit: A digitalized advertising industry is an amorphous and faceless business in which individual organizations and personalities are always less important then the challenges being faced and the ensuing solutions. An unrestrained quest for recognition may make the system rigid and unresponsive. 7. Never Get Satisfied: In a market defined by change and innovation, satisfaction and complacence means deterioration, at least in a relative sense. Always keep an eye on the emerging changes, and in fact visualize and expect the things to change. 8. Vision is a Must: A thorough vision of the nature of things to come and panache for imagination and

My Grandmothers Bedroom Essay Example | Topics and Well Written Essays - 1000 words - 1

My Grandmothers Bedroom - Essay Example One could not fail to notice the jasmine smell and the sweet scent of flowers that was right in front of her balcony. My grandmother had planted a lot of Chinese plants which she had valued them as medicinal through their good scent. Her green stripped door always reminded me of her favorite colors which he had grown fond of since childhood. The doorknob to the bedroom is aluminum plated one, which when touched, sends shivers down your spine as it is always cold. In opening her door, no one could fail to notice the sultry scent that passed through one's nostrils. The place had poor lighting as all the windows had been locked; hence one had to grapple with the main light switch at the right-hand side of the entrance so as to have light. Getting the switch is not an easy task too as your eyes maneuver through the dark lit room. After finding it, one always made a sign of relief as the place is just creepy. The first thing one always notices after switching on the lights in the bedroom is an old black sewing machine positioned in the center of the room. The machine has never been used for over 10 years and as far as I can remember, my mother ever told me that it was the best gift which my grandfather gave to her when they got married. One could not fail to notice how dusty it looked. Furthermore, on the furthest corner of the room, an old hanging clock existed. Though old, it still functioned. Dusty and hanging clumsily on the wall, no one could notice that the wall clock had been there for the past 20 years. Next, to it, there were three pictures, one for my grandmother, one for my grandmother and a picture of Virgin Mary. My grandmother was a Catholic and one could not fail to notice a rosary hang next to Virgin Mary’s portrait. This came as a surprise as most Chinese do not actually believe in Religion.

Strategic implications of Corporate Social Responsibilities Essay

Strategic implications of Corporate Social Responsibilities - Essay Example According to Forbes (2012), involvement in CSR results in creative development and cost reduction within the organisation. An organisation, that is focusing upon sustainability will innovate and undertake methods to achieve the purpose. Such steps often result in creation of a new product that is eco-friendly and cost efficient. Forbes (2012) highlighted at least six reasons for organisations to incorporate CSR in their business activities: innovation, cost advantage, brand differentiation, long term strategic importance, customer engagement and employee engagement. Innovation, in context of CSR, can result in identification of multiple of sustainable business opportunities emerging ahead of an organisation. For instance, Unilever, as a part of its CSR towards environment, was able to develop a new hair conditioner that unlike other substitutes required less water. Once sustainability is incorporated in activities, it is obvious to witness effective utilisation of resources, efficien t consumption of energy and other non-renewable resources and increased usage of eco-friendly materials. It has been observed so far that brand differentiation has become one of the primary reasons for organisations to embrace CSR. Prominent companies such as Coca-Cola and Pepsi have incorporated brand differentiation in their products such as water bottles that are recyclable in nature, to enhance their brand image as sustainable organisations. In addition to brand differentiation in this interactive environment which can be achieved.

The French Revolution and Modern French Socialism Essay Example for Free

The French Revolution and Modern French Socialism Essay The French Revolution Introduction How does the declaration of the rights of man and the citizen defy the political and social convection of absolutism and reflect enlightenment thinking as the basis for a new French society            The passing of the declaration of the Rights of Man and Citizen in 1789 was the most profound thing that had a significant effect on the oppressed class. Before the declaration of The Righs of Man and Citizen, France was divided into a rigid oppressive social class, the clergy, the nobility and the peasants. The unequal class created the environment for the oppressed peoples to fight for their sovereignty, fraternity and equality. The outbreak of the French revolution in 1789 also made people from the St. Domingue to fight for their freedom, which broughtabout conflict between the various classes. The French revolution decreed equal rights to all citizens. Prior to the declaration of the rights of man and citizens, conflict arose between the people of color of St. Dominge and the whites (Goodwin, 219).            The incorporation of the writings of enlightenment thinkers such as Jean-Jacques Rousseau and Montesquieu were the guiding principles of the rights of man and citizen. According to Rousseau, the social contract between the ruled and the rules required rulers to obey the general will of the people, thus, if the rulers failed to do so, the people had the right to overthrow them. These ideas declared that the sovereignty of the people is located in them and nobody could exercise power over them, unless allowed by them. Such enlightenment made the people to have the political authority over their nation. Moreover, the declaration proclaimed gave the people power to remain free and acquire equal rights and protect the rights of the Frenchmen.            Prior to the Declaration of the Rights of Man and the Citizen, a new French social contract was created whereby the constitution of 1791 was invalidated by progressive tension between the king and the deputies. The new French social contract changed the political and social contract systems to that of the sovereignty where people’s opinion had to be considered. The new French social contract that was created made the people who were divided about power to have conflict among themselves and the many elements of the people who felt themselves excluded such as women and the poor and whose status were not improved. As a matter of fact, Louis XVI was condemned to death and executed and the convections drew up a new constitution that reflected the enlightenment of thinkers such as Rousseaus concept of a social contract grounded on the general will (Goodwin, 231).            Moreover, the 1793 constitution reflected much on the enlightenment of Rousseau social contract held by the Jacobins. The imposition of this constitution in France generated a power struggle that resulted in the expulsion of more moderate divisions from the state and the concentration of power in Jacobian hands. The requirement of prosecuting the war against Europe joined Jacobian control, but competing interests and power conflicts remained. The deportment of the war, personal ambitions, and economic tensions all experimented the leadership of Jacobian so as to maintain the control and impose the version of the general will. It was all a counter check and violence against opponents so as to ensure the rights of man and citizen is maintained (S, 380). When reading the official indictment (formal charges) of Louis XVI, do you believe the National Convection is justified in condemning the king for reasonable treasonous actions? Or do these charges appear groundless?            Drawing from article 2 of the 1791 constitution, â€Å"the person of the king is inviolable and sacred: his only title is king of the French† (Paine,107), there was no need for the National Concetion to condemn the king for reasonable treasonous actions. Indeed, it’s only a vigorous challenge of royal inviolability that followed the King’s flight to Varannes. It was the work of the convections for the king to be tried by the legislature. The charges appear to have a constitutional base because the king should maintain and follow the constitution of the land. It is for this reason that the Convection places a trial against the king. However, though the charges are based on the constitution the Convection has divergence arguments about the King’s trial and have no prove that the King has committed all the crime that has been imputed to him. Moreover, the inviolability issue that was imputed on the King was by no means be confined to discus sion at the tribune of the Convection. For example, Jacques Necker acknowledges that the Convection has no power to try the King for inviolability. He argues that â€Å"The king cannot be tried as a particular and that he had not violated any constitutional laws†. Moreover, â€Å"He buttressed royal inviolability with historical references† (Paine, 110), noting that the kings could not in either way be tried by their aristocracies neither by partial men, and declared the constitutional doctrine both necessary and just. Likewise, an an anonymous pamphleteer providedandeceptive rarity for the King trial.            Moreover, the only claim that is seen is the issue about inviolability whereby the report from the Legislative body was just a question about whether Louisxvi was judgeable for the crimes he was imputed to have committed. As a result, the king was suspended by the Assembly whereby the Convection was given the mandate to elect the sovereign will. This affected the denial of noble inviolability, which seem as if it never existed. Likewise, the decision to focus consideration only on the article one of the committee report is a clear indication that Louis could not have been convicted because the convectionels were the one pushing for his conviction through attacking the â€Å"stupid dogma of inviolability†. Therefore, though there was no need for a trial against Louis XVI because he was already accused and condemn by the people, I do not agree that his condemnation was justified. It was more of a political condemnation (Paine,119). Upon reading, â€Å"The Execution of Louis XVI† as seen by Henry Edgeworth de Firmont, does the king appear brave, frightened or insolent on the way to his execution?            From the execution scene, the king appears brave on the way to his execution. The king seems to understand his mistakes. It might be the condemnation of the people that has forced the king to have extra courage because he is no longer needed in the society. It is the people who have convicted him to death and nothing he can do to go against their will. As we can see as soon as the king descended from the carriage, three executioners surround the king and wished him to take off his coat and though he repulse them, he does it with dignity and took it off himself. These are signs of a brave person.            The king also shows his bravery whereby when the executioners try to tie him, he abruptly withdraws his hands without fear, and the situation seems to exceed the executioners. He also responded in an indignant tone. Nevertheless, the king is also frightened of what he will undergo. He knows very well he must be executed. As we can see, his eyes are filled with a sorrowing look that turn to the executioners maybe to seek them to save him. His courage had started to weaken by the pain he seemed to take. According to the king, he is dying of innocent of all the crimes he has been imputed upon him. It might be true considering that he knows very sure the decision of the people is final and he has to face the death sentence. He therefore says in a frightened tone, â€Å"I pardon the authors of my death, and pray God that the blood you are about to shed will never fall upon France†. References Goodwin, A..The French Revolution,. London: Hutchinsons University Library, 1953. Print. Paine, Thomas. Rights of man being an answer to Mr. Burkes attack on the French Revolution.Waiheke Island: Floating Press, 2010. Print. S., A. W.. Book Review:The French Revolution and Modern French Socialism. A Comparative Study of the Principles of the French Revolution and the Doctrines of Modern French Socialism. Jessica Peixotto. American Journal of Sociology 7.5 (1902): 706. Print. Source document

Structures of Bacterial Tyrosinases

Structures of Bacterial Tyrosinases Tyrosinases oxidise phenolic hydroxyl groups of small molecules or large polymeric substrates such as proteins. Tyrosinases catalyse first the ortho-hydroxylation of the phenolic substrate and second its subsequent oxidation to quinone (Figure 1) with the concomitant reduction of oxygen to water. The reaction is chromogenic as the quinones produced can undergo further non-enzymatic polymerisation to form black eu-melanins and, when reacting with thiol groups, brownish pheo-melanins [14]. This process can be inhibited by antioxidants such as ascorbic acid, for example to prevent the browning reaction in food preparations [15]. Tyrosinase activity is generally measured by either determining the consumption of oxygen during the reaction or spectrophotometrically by following the increase of absorbance at 475 nm due to dopachrome formation. The cross-linking activity of tyrosinase on proteins is usually analysed by SDS PAGE, size-exclusion chromatography, UV spectroscopy or mass spectrom etry [16]. The active site of tyrosinases interacts with both the phenolic substrates and the co-substrate oxygen and it alternates among three different oxidation states. When in the oxy state, tyrosinase binds oxygen and is able to catalyse the hydroxylation of monophenols to diphenols, thus changing into the met form. The met form of tyrosinase is responsible for the oxidation of diphenols to quinones and the reaction turns the enzyme into the deoxy form that, upon binding molecular oxygen, returns to the oxy form. The met form is the resting state of the enzyme and it has been calculated that up to 85% of the enzyme is in this state when in solution [17, 18]. The inability of most of the enzymes in an enzyme population to act on monophenols explains why a significant lag phase is detected in the activity when monophenols are the substrate of the reaction. Bacterial tyrosinases have been divided in five types according to the organisation of domains and the possible requirement of a caddie protein for enzyme activity [12]. The necessity of a secondary helper protein (caddie protein) for secretion, correct folding, assembly of the copper atoms and activity of the enzyme is common to tyrosinases of type I, e.g. the enzyme from S. castaneoglobisporus and S. antibioticus [19, 20]. Type II tyrosinases are small, monomeric enzymes containing only the catalytic domain, which do not require additional helper proteins and are possibly secreted. An example is the tyrosinase from B. megaterium [6]. Type III tyrosinases are represented by the enzyme from Verrucomicrobium spinosum. Like the fungal tyrosinases it carries a C-terminal domain whose removal led to about 100-fold higher activity [21]. This supports the theory that the role of the C-terminal extension in plant and fungal tyrosinases is to keep the enzyme in an inactive form inside the ce ll [22-24]. Among the smallest bacterial tyrosinases reported (Type IV) are the ones produced by Streptomyces nigrifaciens (18 kDa) and Bacillus thuringiensis (14 kDa) [25, 26]. However, it is debated whether these proteins are true tyrosinases [12]. Type V tyrosinases include enzymes that do not carry the sequence features of tyrosinases but show features typical of laccase and have only marginal activity on tyrosine. For example, a membrane-bound tyrosinase active on the typical laccase substrate ABTS (NCBI ID: AAF75831.2) has been isolated from Marinomonas mediterranea. A tyrosinase with a classical substrate specificity that is activated by SDS (NCBI ID: AAV49996.1) has also been reported from the same organism [27]. Similar to catechol oxidases and the oxygen carrying haemocyanins, tyrosinases are type-3 copper proteins, containing two copper atoms in the active site. The absorbance spectrum of oxy-tyrosinases has a characteristic maximum in the UV region (330-345 nm). As reported for the structurally similar catechol oxidases, a fluorescence intensity maximum at 330 nm upon excitation at 280 nm is also detected [28, 29]. Copper is essential for the catalytic activity of tyrosinases. The crystal structure of these enzymes has demonstrated the presence of two copper ions in the catalytic core (Table 1). In all tyrosinases of different origins and in the haemocyanins each of the copper ions is coordinated by three histidine residues that are found in a characteristic pattern in the primary structure (Figure 2). In the tyrosinase from Streptomyces glaucescens, for example, the key role of histidines at position 37, 53, 62, 189, 193 and 215 in the coordination of copper, and thus in catalytic activi ty, was confirmed by the decrease of activity upon their substitution with other amino acids [30, 31]. Various additional residues have been identified to have a function in fungal and bacterial tyrosinases, either being essential for or modulating tyrosinase activity. Sequence analysis and various mutagenesis studies have been performed in order to identify the residues necessary for the activity of the enzyme. In tyrosinase sequences from plants and fungi, the N-terminal signal peptide, when present, is followed by a conserved arginine residue that marks the beginning of the central catalytic domain and that forms a pi-cation interaction with a conserved C-terminal Y/FXY tyrosine motif, where X is any amino acid [32]. These residues are conserved also in bacterial tyrosinases (Supplementary file 1). Substitution of the N-terminal conserved arginine (R40) has been reported to abolish the production of tyrosinase from V. spinosum [21]. Two single-amino acid substitutions have been reported to improve the catalytic activity of the tyrosinase from Rhizobium etli CFN42. The independent r eplacement of proline at position 334 and of aspartic acid at position 535 (Supplementary file 1) with a smaller residue such as serine (P334S) or glycine (D535G), respectively, led to a significant enhancement of the catalytic activity and melanin formation [33-35]. In the tyrosinase from B. megaterium, a single substitution of arginine by histidine within the copper B binding region (R209H) has been sufficient for a 1.7-fold improvement of the activity towards tyrosine (monophenolase) and for a 1.5-fold reduction of activity on L-DOPA (diphenolase), whereby the overall protein stability was not affected [36]. The crystal structure of the tyrosinase from B. megaterium showed that this arginine is positioned at the entrance of the active site in a flexible position and plays a role in the docking of the substrate [6]. However, the conservative substitution of the corresponding residue asparagine 190 to glutamine (N190Q) in S. glaucescens tyrosinase abolished the catalytic activity, indicating that this residue was possibly involved in hydrogen bonding at the active site [30]. Moreover, the conservative substitution of the residue aspartic acid 209 (D209E) has been reported to stabilise the oxy-form of the same enzyme [37]. To our knowledge, no study has investigated the role of the oxygen binding motif PYWDW [38] with regards to the affinity for oxygen in tyrosinase. The affinity for the co-substrate oxygen has been evaluated for the tyrosinase from Streptomyces antibioticus that carries the PYWDW motif. It was found that this enzyme had a three-fold lower dissociation constant (kD) for oxygen than the A. bisporus tyrosinase [39, 40] that carries a PFWDW motif, i.e. 16.5 ÃŽ ¼M compared to 46.6 ÃŽ ¼M. The analysis of the characterised bacterial tyrosinases evidenced the presence of functionally active variants of this motif (Supplementary file 1 and 2), e.g. PYWNY in the tyrosinase from M. mediterranea, PFWDW in tyrosinase from R. etli, PYWEW in the tyrosinase from B. megaterium, PYWRF and PYWNW in the tyrosinases from Ralstonia solanacearum. Mutational studies have also addressed the interaction of tyrosinases from streptomycetes and their caddie protein. In S. antibioticus, the two histidine residues at positions 102 and 117 of the caddie protein MelC1 have been found to be crucial for the biosynthesis of active tyrosinase [41]. The available crystal structures of bacterial tyrosinases and their mutant forms have been obtained from Gram-positive S. castaneoglobisporus and B. megaterium (Table 1). While the B. megaterium tyrosinase formed crystals containing only the enzyme, the S. castaneoglobisporus tyrosinase required the presence of a second protein, referred to as caddie protein, to stabilise its structure [4]. Moreover, the structure of the Streptomyces tyrosinase has been solved in different states of oxidation. Aiming at understanding the interaction between tyrosinase and caddie protein, tyrosinase has been crystallised in the presence of mutant forms of the caddie protein (Table 1). Likewise, the fungal tyrosinase from A. bisporus was crystallised as a tetramer in a complex with a second protein, a lectin-like protein [7]. Both intracellular and secreted bacterial tyrosinases have been isolated and characterised. For example, the tyrosinases from Streptomyces nigrifaciens, Bacillus thuringiensis, M. mediterranea, R. solanacearum and Thermomicrobium roseum were isolated from cell biomass and the ones from S. antibioticus, S. glaucescens, S. castaneoglobisporus, Streptomyces albus, B. megaterium, Sinorhizobium meliloti, Aeromonas media, R. etli and V. spinosum were either isolated from the culture medium or predicted to be secreted [19, 21, 25, 26,42-51]. The twin-arginine signal peptide is often found in cofactor-binding oxidoreductases that undergo complete folding in the cytoplasm prior to secretion to the periplasmic or extracellular space. Twin-arginine type signal peptides [52] could be identified in the N-terminal region of tyrosinases from R. solanacearum (34-amino acid long) and V. spinosum (33-amino acid long). A more detailed analysis of the sequence retrieved for the tyrosinase from R. etli a nd the alignment with the other sequences of tyrosinases (Supplementary File 1) suggests the possibility of incorrect open reading frame prediction. The true N-terminal methionine may be M112 (underlined in Supplementary file 1) as it aligns with the initial residue of the tyrosinase from R. solanacearum (number 15 in Supplementary file 1) and is followed by a predicted twin-arginine signal peptide of 31 amino acids [51]. Thus, we suggest that these proteins purified from the cell biomass but carrying a signal peptide for secretion are localised in the periplasm. Tyrosinases, also from bacteria, and their caddie proteins generally lack conserved cysteine residues (for comments see [11, 12]). The paucity of cysteine residues, and thus disulphide bonds, allowed, however, the isolation of tyrosinases with significant thermal stability, e.g. the enzyme from B. megaterium had an optimum temperature of 50Â °C [48]. A single cysteine residue is conserved in proximity of the second histidine residue of the copper A binding motif in the characterised tyrosinases from M. mediterranea, R. solanacearum, S. meliloti, R. etli and V. spinosum (Supplementary file 1). A cysteine residue at this position has been found to be covalently bound to a histidine residue two positions forward in, for example, the fungal tyrosinase from Neurospora crassa [53], the plant catechol oxidase from I. batata [8] and haemocyanins from the snail Helix pomatia [54]. The function of this unusual cysteine-histidine bond is not established, but it could confer structural rigidity to the copper-binding region and affect the redox potential [8]. Replacement of this cysteine residue (C84) with serine abolished the production of the tyrosinase from V. spinosum [21]. Type-3 copper proteins carrying six conserved cysteines (forming three in silico predicted disulphide bonds) and characterised by significant thermal stability have been reported in fungi [26]. No mutagenesis study has addressed a possible improvement of the thermal stability of bacterial tyrosinases by introducing disulphide bonds. However, in silico analysis revealed the possible presence of one disulphide bond in the tyrosinases from R. solanacearum and S. meliloti and two in the enzymes from M. mediterranea and R. etli (Dianna software, http://clavius.bc.edu/~clotelab/DiANNA). The tyrosinase from S. castaneoglobisporus and the one from B. megaterium share approximately 30% sequence similarity with a catechol oxidase from Aspergillus oryzae that showed a melting temperature above 70Â °C and a ha lf-life of 20 hours when incubated at 50Â °C [29]. It should be noted that the tyrosinase from A. media exhibits different sequence features when compared to the other enzymes. The sequence alignment with bacterial tyrosinases shows that none of the typical signature motifs (copper A and B regions, oxygen binding motif and tyrosine motif) are present (see Supplementary file 1). Moreover, this enzyme has a predicted 23-amino acid long signal peptide [50] and shows strong sequence similarity to bacterial periplasmic proteins that are responsible for the uptake of peptides and involved in nutrition and sensing of the environment [55].