Factors in Biochemical Toxicology

Factors in Biochemical Toxicology Tambudzai Phiri Ndashe Maha Farid In the lecture we discussed several responses of the lung to acute injuries. List these responses and discuss one of these responses providing an example of a toxin or a chemical that induces such response in the lung. (5 points) The lung is particularly vulnerable to toxicity because it gets exposed to foreign compounds both in the external environment and internally through the bloodstream. Acute responses of the lung to injury occur in order to protect the lung from further damage. These responses include the following: Irritation following exposure to volatile gases such as ammonia and chlorine may cause bronchitis and changes in permeability. Exposure to gases or irritants may also lead to damage of the epithelial lining of the entire respiratory tract. Irritation of nerve endings in the respiratory epithelium may occur following exposure to gases or irritants to protect from further exposure. Xenobiotic metabolizing enzymes such as Glutathione S-transferase in the lung tissue also play a role in the pathogenesis of pulmonary toxic response. Oxidative burden following exposure to gases such as ozone, nitrogen dioxide or tobacco smoke. Airway reactivity and bronchoconstriction may occur on exposure to nitric oxides, cholinergic drugs, histamine and tobacco smoke. Pulmonary edema may occur as result of high concentrations of acrolein, hydrogen chloride, nitrogen dioxide, ammonia or phosgene. Pulmonary edema Pulmonary edema is the accumulation of fluid in the lung, which collects in the alveoli; it leads to impaired gas exchange and may cause respiratory failure (Medical News Today, 2014). Exposure to ammonia, a volatile and water soluble gas, has been associated with pulmonary edema. The ammonia gets absorbed into the aqueous secretions of the upper airways of the respiratory system, it reacts with the water in aqueous secretions to from ammonium hydroxide, an alkaline and corrosive solution. Though ammonia may not cause permanent damage it leads to impaired permeability and the accumulation of fluid which obstructs the upper airway and collects in the air sacs. This may lead to low blood oxygen content and altered mental status (Center for Disease Control and Prevention, 2014). The dissolving of the ammonia into aqueous solutions on mucous membranes may also result in corrosive injury to the mucus membranes. High concentrations of acrolein, a common component of smoke, can also cause p ulmonary edema following smoke inhalation. Paraquat, is a widely used herbicide that specifically exerts its toxic effect on the lung tissue. Discuss the mechanism of toxicity of paraquat explaining the specificity of lung toxicity induced by this compound. (5 points) Paraquat has been implicated in number of both accidental and intentional cases of poisoning. It causes dose-dependent toxic effects following oral ingestion; and, absorption of a toxic dose usually results in abdominal pain, vomiting and diarrhea. In addition to the lung, other target organs include mainly the kidneys, but may also cause cardiac and liver toxicity if one if exposed to large doses. Mechanism of paraquat toxicity on the lung Paraquat is selectively taken up into type I and II alveolar epithelial cells by active transport, as a result it reaches a higher concentration than in most other tissue. It causes severe lung injury and fibrosis. The mechanism of toxicity involves the initial reaction of paraquat with an electron donor such as NADPH; paraquat accepts the electron to form a stable radical cation (Figure 1); if this occurs under aerobic conditions, this electron is transferred too oxygen giving rise to superoxide; this process gets repeated over and over in the lungs due to the ready supply of oxygen, resulting in the formation of a redox cycle. The formation of the redox cycle is believed to be responsible for the toxicity by causing the following effects: the formation of large amounts of superoxide may overwhelm the neutralizing effects of superoxide dismutase, allowing the superoxide to accumulate, causing a variety of toxic effects such as the peroxidation of lipids leading to the formation of l ipid radicals that may cause membrane damage (Figure 2); and, the depletion of NADPH due to the formation of active oxygen species may compromise the alveolar cells, reducing their ability to carry out their functions. Figure 1: paraquat reduction-oxidation. Figure 2: the proposed mechanism of paraquat toxicity. Figure 1: adapted from http://www.inchem.org/documents/jmpr/jmpmono/v086pr05.gif Figure 2: adapted from http://totalpict.com/imagesb/1818/1818064104502cc34b8ffb7.gif References Timbrell, J.A. (2009). Principles of Biochemical Toxicology, 4th Edition. CRC Press. Pages 204- 205; and, 337-339. Medical News Today (2014, September 15). What is pulmonary edema? What causes pulmonary edema?  Retrieved from: http://www.medicalnewstoday.com/articles/167533.php The Center for Disease Control and Prevention (2014). Medical Management Guidelines for Ammonia. Retrieved from: http://www.atsdr.cdc.gov/MMG/MMG.asp?id=7tid=2 Maha Farid Discuss the patterns of neurotoxicity and provide one example of a toxin producing each pattern. Examples from the assigned textbooks are recommended. (6 points) The nervous system is a highly complex network of specialized cells and damage to this system may have permanent and serious effects because there is very low capacity to regenerate and little reserve functional capacity. The following are the patterns of neurotoxicity: Neuronopathy: this is the result of the destruction of the peripheral nervous system, or simply put, death of the entire neuron. The drug contaminant 1-mehtyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) causes specific damage to the substantia nigra area of the brain (Timbrell, 2009). It is highly lipophilic and readily enters the brain where it is readily metabolized to a toxic metabolite that is taken up by dopamine neurons. Methyl mercury also causes Neuronopathy. Axonopathy: this is the degeneration of the axon. Carbon disulfide exposure is a good example of a neurotoxin. Exposure to this solvent usually occurs in industry and causes neuronal damage in the central and peripheral nervous systems. The mechanism is believed to involve the chelation of metal ions essential for enzyme activity by the oxothiazolidine and dithiocarbamate metabolites of carbon disulfide, which result from reaction with glycine and glutathione (GSH) (Timbrell, 2009). Myelinopathy: this is a general term used to describe damage to or disorder of the myelin of peripheral nerve fibers, the myelin sheath or the white matter of the brain, in contrast to that affecting the axons (Axonopathy). A number of substances cause Myelinopathy in both the Schwann cells and the Oligodendrocytes. Lead is a good example of a neurotoxin that causes Myelinopathy, especially in children. Transmission toxicity: this is the disruption of neurotransmission. Organophosphorus pesticides such as malathion, which is used in the treatment of head lice in humans, and parathion, are good examples of neurotoxins that cause transmission toxicity. Exposure is usually accidental, suicidal or associated with homicide; and occurs via the gastrointestinal tract, the skin and the lungs. They are acetylcholinesterase inhibitors and acute toxicity manifests via the overstimulation of the muscarinic and nicotinic acetylcholine receptors. Nicotinic signs and symptoms result from the accumulation of acetylcholine at motor nerve endings in skeletal muscles and automated ganglia. This results in fatigue, involuntary twitching and even muscle weakness which may affect muscles of respiration. Death may occur from respiratory distress partly due to neuromuscular paralysis, central depression and even bronchoconstriction (Timbrell, 2009). Discuss the vulnerability of the nervous system to toxicity. (4 points) There are multiple characteristics of the nervous system that make it vulnerable to toxicity; in fact the nervous system is highly susceptible to changes in its environment. The characteristics of the nervous system that make it vulnerable to toxicity include the following: Neurons can have very long axons, making them more vulnerable to toxicity. The nervous system is also highly dependent on glucose, which is the sole source of energy to the central nervous system. This high dependence on glucose is demonstrated through fatal irreparable damage to the nervous system, even in brief obstruction of blood flow to the central nervous system. Energy shortage to the nervous system can lead to glutamate leakage which can cause severe brain injury. The long axons and large cell volume in the nervous system require high metabolic activity due to the electrical transmission of action potential and chemical transmission in the nervous system. Proper axonal transport is very essential for normal brain function. There are multiple fast and slow, anterograde and retrograde transport systems that exist in the nervous system, which complicate the process and add to the sensitivity of this area. Reference Timbrell, J.A. (2009). Principles of Biochemical Toxicology, 4th Edition. CRC Press. Pages 206; and, 339-346.

Peace Education :: Essays Papers

Peace Education Peace is not a new concept. People have been studying peace ever since there was conflict, loss, and the realization that we take peaceful times for granted. Peace education, as in peace taught in schools, on the other hand, has been forming mostly over the past three decades. There are several aspects of peace education that are essential knowledge when going to teach peace. In order for peace education to happen the teacher needs to take into consideration the child’s personal history, the environment provided for learning, definitions of peace, the criticism of peace education, the rationale for peace education, the skills, knowledge, and attitudes it aims to develop, and how it relates to the general peace movement. Peace research began as a response to World War II and the publics concern about a nuclear war. It started as a social science that looked at the problems of war in a systematic way as well as the quest for peace. These studies began in France at the Insititute Francais de Polaemologie and in a few graduate programs in the United States, such as Stanford, Northwestern and Yale. It focused primarily on foreign policy changes in a hope to prevent a World War III. The critics agreed that there needed to be peace research, but they believed it needed to be broadened. As it stood, peace research consisted of researching conflict not peace, and problems not the solutions. Over time these criticisms grew until the 1960s when they were coupled with the Third World Liberation movements, which created small scale revolutions and mounted up to the Indochina war. This was a turning point in peace research. Researchers began focusing on â€Å"positive peace† instead of reactionary peace. I n 1966, John Galtung established the Peace Research Institute in Oslo (PRIO). Shortly after the establishment of PRIO, the Stockholm International Peace Research Institute (SIPRI) opened. These institutes remain to this day reputable and thoroughly used by scholars. In the United States, the peace research movement was taking form through colleges by publishing scholarly journals, such as the Journal of Conflict Resolution at Swarthmore College. The end of the 1960s marked another shift in peace research. â€Å"We must gather together all the elements of this new world and organize tem into a science of peace.† (Montessori, 31) Peace science, as it was now deemed, was shifting from physical violence and war towards structural violence, such as capitalism, racism, colonialism, and imperialism.

Solzhenitsyn’s Exile :: Russian European History Papers

Solzhenitsyn’s Exile missing works cited â€Å"In February 1956, the Soviet Union’s new leader, Nikita Khrushchev, initiated a period in Soviet history known as ‘The Thaw’ †¦ Millions of former political prisoners were granted amnesty, including [Aleksandr] Solzhenitsyn.† (Shattan 149) Solzhenitsyn is Russia’s most prolific writer of the 20th century was Aleksandr Solzhenitsyn, a man who rose to fame through his literature. It was Khrushchev’s thaw, however, that resulted in Solzhenitsyn’s exile. Solzhenitsyn made his break in literature because of Khrushchev’s thaw. Yet as time went by, the Soviet leadership became increasingly conservative after the thaw. Initially, the conservative leadership did not know what to do with Solzhenitsyn, but after deciding to take action against Solzhenitsyn, they eventually worked towards a final solution, his deportation from Russia. Had it not been for the thaw, though, Solzhenitsyn would never have made the rise to fam e, and his deportation. Aleksandr Solzhenitsyn first became active in politics during his time in Rostov University prior to World War II, during which time he became â€Å"a convinced Communist - a member of the Komsomol (Young Communist League)†¦ and the proud holder of a Stalin scholarship.† (Shattan 137) After graduating in 1941, Solzhenitsyn joined up with the Russian artillery to fight the Nazi army. During this time, he began to formulate a belief that Stalin â€Å"had betrayed Leninism and was responsible for the defeats in the first phase of the war† (Shattan 140) He communicated these ideas with a friend through letters, but was caught by censors and imprisoned. During his time in prison, which would provide the material for One Day in the Life of Ivan Denisovich, it was discovered by Soviet authorities that Solzhenitsyn had a degree in physics. Because of this, he was transferred to a special science prison, where prisoners worked on Soviet experiments. In 1953, his term served, Solzhenitsyn was released from prison, but forced into an internal exile in southern Kazakhstan. However, in 1956 this exile was ended by the new Soviet leader, Nikita Khrushchev, who initiated â€Å"The Thaw† by releasing millions of political prisoners. Solzhenitsyn was free to write and to travel. In a society that had repressed its writers for the last 30 years, it was extremely difficult, and quite a gamble, for an author to try to publish a book, much less one that criticized one of the only two leaders the single party state had known.

Creatures On My Mind :: essays research papers

â€Å"Creatures on My Mind† In the short story, â€Å"Creatures on My Mind,† by Ursula Le Guin, there were many different symbols throughout the story. The author talks about a beetle, a sparrow, and a gull to get the reader to understand what she is trying to say.   Ã‚  Ã‚  Ã‚  Ã‚  The character first starts out talking about a experience she had while sitting on her porch. While sitting their she recognized a beetle lying on it’s back twitching and suffering. She thought about ending the beetles life but couldn’t put herself through it. I think the that the beetle represents how human interaction should be looked at. Human interaction should be looked at what’s on the inside not what’s on the surface, and to take feelings into consideration. When the character doesn’t end the life of the beetle he reveals that she respects all living things, even things she can’t stand.   Ã‚  Ã‚  Ã‚  Ã‚  The second experience that the character stumbles upon is a sparrow trapped in a cage. The character finds someone with a key to open the cage and successfully lets the sparrow go. This experience shows us that we will go out of our way to help a helpless, hurting creature, but the way we go about doing it isn’t always the right way. We can relate this experience to how we help the homeless. The way I can relate the sparrow to the homeless is we help the homeless like the sparrow, but we aren’t always happy when we do it.   Ã‚  Ã‚  Ã‚  Ã‚     Ã‚  Ã‚  Ã‚  Ã‚  The third and last experience that is talked about in the story is how the character finds a gull with a broken along side the water. All the character thinks about is if a dog come by and saw the gull sitting there helpless with a broken wing.

I Believe in Forgiveness Essay

I never really understood the meaning of forgiveness. When people hurt me or treat me badly I always thought the best way to handle it is to hold it in. I never showed anger on the outside but just kept it all in. Instead, I let it boil inside of me. My kind act toward those who hurt me was a shield from my pain. Most of my kind act was at my mother. I blamed my birth mother for every relationship I have ever been in that ended with my hurting the guy or me thinking I am just going to be like my mother and leave him for the next person. see more:to err is human meaning Over the years, her actions and mishaps became the victim for my own actions. The fact that I have not yet become a divorcee like her was justification for her being irresponsible, dishonest, and ungrateful. Throughout the years of struggle, dysfunctional relationships, and little to no relationship, I hardly took responsibility for anything that I had done. I laid all my relationship troubles on my birth mother. I call her my birth mother because I never grew up with her but I have met her from time to time. She gave me to my dad when I was seven years old because of another man. I blame my relationship trouble on her because she never had a solid relationship for me to learn from. She has been married four times and the longest have been a year and that was to my dad. Then a few months ago, something shocking happened to me: I was in a committed relationship for the first time in my life. I was so scared I would be just like her or I was going to ruin this wonderful guy’s life. One night, as I was trying to sleep, thinking about my life, I suddenly became filled with fear. I was convinced I would screw up my life —that all my fear of being like her was tarnishing my relationship life. Strangely, while panicking about my life becoming a doom, my mother came to mind. I sat there in the dark, surrounded by the soothing sounds and smells of my air freshener in my room, and I thought of how my mom must have blame her mother for the same reason I am blaming her. I knew at that moment that she never intended to hurt me. I realized that might have been as scared like I am when it comes to commitment just as I am. I knew that she had done the best she could to stay in those relationships, but it was not the right thing to do. I forgave my mother that night—for all the times she got divorced, embarrassed me, or hurt my father or made me feel like I can never have a relationship because I always think I would end up like her. I forgave her for not being around. I let go of the resentment I’d held toward her for so many years. I stopped blaming her. For some reasons maybe my reasons were not very noble. Maybe I was afraid my life would turn out to be just like hers or maybe I might never find that person to settle down with. Whatever the reason, for the first time, I saw my birth mom as a real person. A person with flaws and mistakes. I knew she did not jump from marriage to marriage to hurt me. She got divorced for four times because she was flawed and hurting. I knew that if I did not forgive her, I would never have the kind of relationship I wanted with my future husband. If I kept blaming her I would never start living my own life. My mom have not asked for my forgiveness; she’s never acknowledged that she’s done anything wrong. But I realized that in forgiving her, what I was really doing was taking responsibility for myself and my own actions for the first time in a long time. Forgiving my mom changed my life. I accepted her for who she was and that set me free. I realized that when we forgive someone it is not for them but for you. After I forgave her it was like a burden was taken off my shoulders. I felt this inner peace that I have never felt before. My relationship with my boyfriend is going good and I don’t think or say to myself that I am going to end up like my mother. My eyes are open now to my own failings. I am going to take responsibility for every mistake I make in my relationships and not blame someone for them. And I discovered that forgiving someone is both an innately spiritual act that brings us closer to a higher power, and a uniquely human act that connects people in a way that strengthens us all. Forgiveness is a powerful thing. This I believe. I Believe Essay Draft 1 09/12/12 Word Count 752 The Power of Forgiveness I believe in forgiveness. I never really understood the meaning of forgiveness. When people hurt me or treat me badly I always thought the best way to handle it is to hold it in. I never showed anger on the outside but just kept it all in. Instead, I let it boil inside of me. My kind act toward those who hurt me was a shield from my pain. Most of my kind act was at my mother. I blamed my birth mother for every relationship I have ever been in that I had to end because I feel I am going to hurt him or he is going to hurt me. Over the years, her actions and mishaps became the victim for my own actions. The fact that I have not yet become a divorcee like her was justification for being irresponsible, dishonest, and ungrateful. Throughout years of struggle, dysfunctional relationships, and little to no relationship, I hardly took responsibility for anything that I had done. I laid all my relationship troubles on my birth mother. I call her my birth mother because I never grew up with her but I have met her from time to time. I grew up with my loving stepmother and father. She gave me to my dad when I was seven years old because of another man. I blame my relationship trouble on her because she never had a solid relationship. She has been married four times and the longest have been a year and that was to with my dad. Then a few months ago, something shocking happened to me: I was in a committed relationship for the first time in my life. One night, as I was trying to sleep, thinking about my life, I suddenly became filled with fear. I was convinced I would screw up my life —that all my fear of being like my mother was tarnishing my relationship life. Strangely, while panicking about my life becoming a doom, my birth mother came to mind. I sat there in the dark, surrounded by the soothing sounds and smells of my air freshener in my room , and I thought of how my birth mom must have blame her mother for the same reason I am blaming her. I knew at that moment that she never intended to hurt me. I realized that might have been as scared like I am when it comes to commitment just as I am. I knew that she had done the best she could to stay in those relationships, but it was not the right thing to do. I forgave my mother that night—for all the times she got divorced, embarrassed me, or hurt my father or made me feel like I can never have a relationship because I always think I would end up like her. I forgave her for not being around. I let go of the resentment I’d held toward her for so many years. I stopped blaming her. For some reasons maybe my reasons were not very noble. Maybe I was afraid my life would turn out to be just like hers or maybe I might never find that person blame. But whatever the reason, for the first time, I saw my birth mom as a real person. A person with flaws and mistakes. I knew she didn’t jump from marriage to marriage to hurt me. She got divorce for four times because she was flawed and hurting. I knew that if I didn’t forgive her, I would never have the kind of relationship I wanted with my future husband. If I kept blaming her I would never start living my own life. My mom hadn’t asked for my forgiveness; she’s never acknowledged that she’s done anything wrong. But I realized that in forgiving her, what I was really doing was taking responsibility for myself and my own actions for the first time in a long time. Forgiving my mom changed my life. I accepted her for who she was and that set me free. I realized that when we forgive someone it is not for them but for you. My relationship with my boyfriend is going good and I don’t think or say to myself that I am going to end up like my birth mother. My eyes are open now to my own failings. And I discovered that forgiving someone is both an innately spiritual act that brings us closer to a higher power, and a uniquely human act that connects people in a way that strengthens us all. Forgiveness is a powerful thing. This I believe. 09/14/12 Process Memo At first I didn’t know what I was going to write about so I wrote down some things that I believe in. some examples like family, forgiveness and friendship. I listen to some of the essays on thisibelieve. om and it gave me an idea of what to write. I made a list of who took me so long to forgive them then I chose one and then I chose one. I wrote down things they did that made me not to forgive them. I also wrote down the process it took me to forgive them. I then developed and created my essay. The workshop in class helped a lot from reading other people’s essay it gave me a better idea of how to arrange my paper. My group members gave me nice idea on how to develop and make it more interesting and correct my mistakes. The workshop helped a lot.

Citizens United V. Federal Election Comission

Resolved: On balance, the Supreme Court decision in Citizens United v. Federal Election Commission harms the election process. My partner and I stand in firm negation of today’s resolution. If my partner and I uphold that the Citizens United decision does not directly harm our election process, then we win today’s round. Contention 1: Citizens United has negligible effect on public participation in elections. In fact, the decision actually supports voter turnout. Many would argue that a bombardment of ads and excessive spending discourage voters, but this is not the case.In fact, there aren’t any studies that back up this claim sufficiently. There are many studies however, that say that ads pique the interest of voters and encourage them to educate themselves about the candidates. The Journal of Politics reports that respondents in 2000 were as much as 10 percentage points more likely to vote if they watched much television (particularly daily news shows) in medi a markets that were bombarded with presidential ads. Exposure to the ads increased intentions to vote by 18 percentage points.Clearly, campaign ads are very helpful when it comes to voter turnout, and after the case, there was a major increase in the amount of ads aired during a campaign according to a Wesleyan study. We have seen a 40% increase in ads since 2008. In addition, the number of ads only increased by 10,000 from 2004-2008 compared to the 300,000 increase from 2008-2012. Allowing corporations to fund ads and Political Action Committees raises awareness for elections, and potentially increase voter turnout. Contention 2: The decision by the court actually prevents corruption.Matthew Melone, a professor from Depaul University, notes that, â€Å"To believe that corporate advocacy will distort the political process and lead to public lack of confidence in the system is to miss the point that influence will continue to be sought by other means. As long as elected officials of fer themselves up for sale there will be buyers. Even if one believes that corporate express advocacy will become a currency for influence peddling, it is less objectionable than other forms of currying political favors: at least corporate advocacy is transparent. Indeed, the type of fairly easily monitored campaign contributions that Citizens United has legalized are the most transparent, least corrupt way for corporations to exert their influence. As a result, according to the Sustainable Investment Institute, 84 percent of large corporations now acknowledge and report their campaign contribution (up from 78 percent before Citizens United). In short, corporations have been given a legitimate, non-corrupt means of contributing to political campaigns and they are taking that opportunity instead of relying on back-door deals and other illegal methods.In fact, transparency after Citizens United was increased. The New York Times says, â€Å"An often-overlooked part of the Citizens Uni ted decision actually upheld disclosure requirements, saying that ‘transparency enables the electorate to make informed decisions and give proper weight to different speakers and messages. ’ Lower courts have embraced the ruling, relying on Citizens United to reject challenges to disclosure laws, often in cases involving political spending related to social issues. † So Citizens United actually made it easier for courts to reject challenges to disclosure laws, and thus creates more transparency.The New York Times also said, â€Å"None of this means that existing disclosure laws are necessarily adequate. But if they are not, the fault lies with Congress and state legislatures, not the Supreme Court. † What many people fail to realize, is that these transparency issues we currently have were around long before the Citizens United decision. Citizens United is not to blame when it comes to corruption, because it actually helps keep corruption out of the electio n process. Contention 3: Our democratic approach in elections is upheld through the decision.The court decision also better upholds the democratic ideals our election process is based on. Our 1st amendment rights give us the freedom of speech. This right does not only apply to individuals, but corporations as well. This is supported by the Supreme Court in such cases as Santa Clara County v. Southern Pacific Railroad Company which dictates that the term person, in the equal protection clause of the 14th amendment, applies to corporations as well as people. In addition, the Supreme Court also ruled in Buckley v.Valeo that money to influence elections is a form of constitutionally protected free speech. So BCRA denying corporations their constitutional rights to donate and spend on elections harms democracy, and goes against our election process. Further, government regulation would inhibit the flow of information from corporations. Justice Kennedy upheld in the decision that â€Å"b y definition, an independent expenditure is political speech presented to the electorate that is not coordinated with a candidate. † It is for the aforementioned reasons that my partner and I urge a con ballot. Thank you.

The Pros and Cons of Using E-Tendering in Singapore

THE PROS AND CONS OF USING E-TENDERING IN SINGAPORE CONSTRUCTION INDUSTRY First names YAP Last name YEE THARM Abstract: E-tendering is a relatively new and modern technique of tending system. The transaction can be done from business-to-business, business-to-consumer or Business-to-government buy and sale of goods, works and services through the Internet or other networking systems. This paper examines the pros and cons of using E-tendering in the Singapore Construction Industry and the future trend of E-tendering in Singapore.Although E- tendering has been used by the various Singapore Government departments for many years on their procurement of materials and services for local and global with great success, however the private sector in Singapore is still slow in using it as a tendering system. As e-tendering is recognized as a state-of-the-art for procurement which is proven to be efficient by the local Government and other advanced countries (eg. US, UK, China, Hong Kong, Canada etc. ), however the low usage by the private section in Singapore shows that there must be some limitation or disadvantages in using it.May be there are some problems on software and the user not competent to use it for this purpose. Or maybe in Singapore there is a need for the government or a private company to lead and provide a national wide scale of centralizes e-tendering system to cater for all the private tenders in Singapore Construction Industry. Whatever it is, the advantages of E-tendering are far exceeding the disadvantages and it has shown greater potential in the improvement of efficiency to replace the traditional tendering system.Therefore a study to look into the pros and cons of this tendering system is worth the effect. As eventually E-tendering has great potential in increasing efficiency in construction sector in Singapore-tendering by cutting down the-tendering cost and time and reduce the bureaucratic processes in the traditional tendering process. Keywords: E-tender, Singapore’s GeBIZ, E Submission, Information Systems, Pros and cons, Cloud computer, construction. 1. 0 Introduction The use of computer technologies in the world today has revolutionized the processes in the construction industry.The construction industry in Singapore has also faced the same radical and speedy changes in the use of Information Technology (IT) in almost every part of the process of the construction (from pre-tender estimating, tendering, and construction to post tender analysis). Procurement and tendering are an important function for every organisation including construction industry. It is a vital and important activity for a company to gain profit and continue to survive. Especially in Construction Industry, every job is on contract basis, construction company need to secure jobs through tender in order to continue its business.The traditional tendering practices used by Construction Company are largely traditional and involve managing papers or using email to send and receive documents, addenda, correspondence, bid submissions and award notices. With the introduction of submission of tender electronically, time and effort has been shorten tremendously. Other part of the world however electronic tendering has been getting popular over the past few years and is now being commonly used in the United Kingdom, Australia, New South Wales, India, Hong Kong, United States and in China. (The PRC China has been using e-tender for more than 10 years.This year China is celebrating the 10th anniversary of E- procurement rule, their website is www. ccgp. gov. cn). Singapore is a developed country with very good coverage of wireless network and fibre optic cable. The use of computer is very much the common practice of government department and private company. However the use of e-tendering so far in Singapore has been limited to government department procurement. For private construction industry the usage of e-tendering is still limit ed. This paper explore into the pros and cons of using e-tendering in Singapore construction industry and its future development. . 0E-Tendering in the Singapore Construction Industry †¢ E- Tendering in Singapore Private construction: The government department of Singapore has been using E-tendering for more than 10 years, the Singapore Economy Development has also been giving incentive to encourage developers and contractors who are keen in using IT for their business. However up to today the private construction sector in Singapore is still limited in usage of E-tendering. Many Developers and Contractors in Singapore are still finding it more comfortable to use traditional tendering system. †¢ E- Tendering in Singapore Government:The e-tendering used by the government of Singapore is called GeBiz, which come from the word Government Bidding. The GeBIZ, or the Government E tendering, was set up in June 2000. The main objective of this system is to simplify government proc urement and tender activities. It was part of the programme for businesses under the e-Government Action Plan (2000–2003) in Singapore. GeBIZ is a one-stop centre for suppliers to have access to all procurement opportunities in the public sector and to trade electronically with the government departments. The Singapore government E-tender website address is at http://www. ebiz. gov. sg/. Now 100% of the Singapore government Tenders or Quotations are using GeBIZ as a platform for procurement for good and services. As of today, Infocomm Technology (ICT) has become a major part of the Singapore public sector's DNA for public administration and service delivery. Due to the result of Singapore e-government efforts, Singapore has been consistently recognised as a leader in major international benchmarking studies. Our Singapore Government’s innovative efforts in using ICT have also gained local and worldwide recognition and awards.More importantly, the citizens and businesse s have embraced in e-government service. In 2010, almost 9 out of 10 of Singapore citizens and businesses expressed satisfaction with the overall quality of government e-services. (http://www. egov. gov. sg/about-egov-introduction) The process of using Singapore’s GeBIZ: Company who wishes to tender for government job need first to apply as a member of Singapore’s GeBIZ. Upon approved as a member, a password for log in to GeBIZ is given to the company. There are two categories of E-tendering in the GeBIZ. Tender – Goods or services estimated to be valued above $7,000 Singapore dollar. †¢ Quotation – Goods or service estimated be valued below $7,000 Singapore dollar. Once a member log on the GeBIZ, the searching for specific notice can be done by indicating the search condition as shown below by clicking on the â€Å"GO† button. [pic] Figure 1 – searching for a tender (source from http://www. gebiz. gov. sg/. ) For viewing of the details of the-tender and quotation notice, simply click on the â€Å"GO’ button of the screen below. [pic] Figure 2 – viewing of posted tender or quotation. source from http://www. gebiz. gov. sg/. ) The constractor can download or view directly the drawings and specifications posted in the GeBIZ to estimate the-tender price. Tender price can then be submitted to the website electronically. Once the-tender is closed, the-tender will be evaluated by the relevant governmant authority (who post the tender) and the result of the-tender will be announced on the GeBIZ for public information. Hardware and Software requirement for GeBIZ tendering in Singapore. The following are the required hardware and software for a contractor to use the Singapore GeBIZ.In order to use the Singapore Government e-tendering GeBiz, A contractor needs to have a computer meet the following recommended system requirement. The computers which do not meet these requirements might not be compatible and un able to use the system for tender. Hardware – Computer must have a minimum 500MHz processor or higher with a hard disc at least 64 MB RAM, the internet connection to be minimum 256kbps or higher. Software – Computer with a Windows Operating System consist of Windows 2000, Windows XP or Window 7. As for Internet Browser, having a Internet Explorer 6. , 7. x, 8. x and 9. 0 will be enough. 2. 1How E-Tendering works E-tendering is an electronic tendering solution to facilitate the complete-tendering process from the advertising of the requirement through to the signing of the contract. This includes the exchange of all relevant documents (drawing, specifications etc) in electronic soft copy format. In other words E-tendering is a process of carrying out entire-tendering Cycle Online including submission of Price Bid in such that Efficiency, Economy, Speed of Internet can be achieved without the use of paper form of hardcopy.It also eliminates the need to transfer of docume nts between the Client and bidders. E-tendering Cycle can be broken in key modules as the figure below: Figure 3 – The E- tendering cycle 2. 2Traditional Tendering System vs. E tendering The advantages of traditional tendering compare to E-tendering System can be summarised as below: Traditional Tendering System †¢ Longer Procurement Cycle More time needed to print tender documents for all the contractors requesting for tendering. A normal construction tender using traditional tendering system can take up to 2 to 4 months for a cycle. †¢ More ExpensiveThe printing of tender documents such as drawings and specifications are costly and a lot of money is spent for plants and labour for transportation of the documents. †¢ Paper Based Procurement Traditional tendering basically is paper based procurement, documents such as drawings, specifications and forms are printed on paper, which is not environmentally friendly. †¢ Restricted Mobility Paper based tender do cument is not mobile and inconvenient to bring it along for reading and estimation. These documents also require large storage space and it is labour intensive to handle. †¢ Can’t do work on HolidaysThe-tender documents are usually placed at the office and the working hour for office is usually 9am to 5pm. No work can be done after these hours and during weekend and public holidays. †¢ Prone to Human errors Paper documents are prone to human errors, as missing of pages or printing errors. Blur print due to low ink or no ink for some pages can happen. †¢ Content not sharable Tendering documents such as specifications are usually A4 size and can only viewed by a person alone, unlike e-tender document which can be projected to a big screen and shared by as many people as possible for group discussion and meeting. †¢ Physical SecurityTender documents stored in the office especially those documents which have sensitive cost information, e. g. Filled up Bill of Quantity. These documents can pose a business security threats as they are valuable to the competitive contractors. †¢ Wastage of space to store bids Unlike e-tender the documents, the document for traditional tenering need physical space for storage. E – Tendering System †¢ Shorter Procurement Cycle E – Tendering system is computer based; the cycle is much shorter as compare to traditional tendering system. One major saving of time comes from the cutting down of transporting of documents. Economical Due to the fact that hard copies of the documents are expensive, it is very much economical to store and use the soft copies in the computer and website. The cost of using the computer and software are quite fixed. †¢ Environmentally Friendly As compare to traditional tendering system, E-tender consumes almost no paper. Hence it is very environmentally friendly. †¢ Anytime – Anywhere Bidding E-tendering can be conducted any time anywhere i. e. 24 hours a day, 360 days a year and globally anywhere as long as there is Internet connection. †¢ Bidding is possible on HolidaysBidding is possible even during weekend or Public Holiday, as long as before the tender is closed. †¢ Automated & Accurate process As e-tender is automatically carried out by the computer, hence it minimized the human. The process will be accurate and almost instantly done. †¢ Shareable Content The content for E-tender documents is easily shareable among the company staff, as long as they have a computer or laptop and a given a password. The content also easily shared in a group meeting with a projector, which is a conducive environment for group discussion. †¢ Fool-proof SecuritySecurity for the documents is fool-proofed as only authorized people with the password can access to the virtue documents. †¢ Lifelong storage on CD Document stored in the CD or hardisk for e-tender can last for eternity (provided that the CD and hardisk wil l last as long) as compare to paper documents. It is also easy retrievable. †¢ One click access to bids When all the calculation for the-tender sum is done, it is only one click away from bidding. 2. 3Pros and cons to call for e-tenders. Pros to the Suppliers/Contractors †¢ Anytime & Anywhere Bidding Due to the development of wireless communication, E-tendering is globalized.Everywhere in the world as long as you are connected in the website, bidding is possible. †¢ Fair, Free and Fearless participation for vendors. As all vendors registered are treated as equal, the competition is fair, free and no barrier. †¢ No dependence on Newspaper, Courier. All posting is website base, hence the publicity does not require Newspaper or Courier service. †¢ No Administrative hassle The administrative is very much simple and simplified as all documents can be view through the computer screen. †¢ Can carry out all tendering process from any computer E-tendering is web based.Hence any computer, laptop or even I phone can do the job. †¢ Economical Saving on traveling cost is tremendous. As the link between the Client and contractor is through internet, it minimizes the physical travelling. †¢ Reduces efforts & cost of bidding The efforts for each individual staff and the manpower required for preparation of tender is reduced, hence the over cost of bidding is less. †¢ No tenders can be missed because of distance The bosses of the client or contractor may be travelling overseas, but they can access to the E-tender website anytime anywhere in the world. Miss viewing of the tender has become the past. Can submit bid at last minute The closing of E-tender is link to the time. As no travelling is needed to the client’s office to submit a tender, contractor can always clip the submit on the last minute/second. Pros to the-tendering Authorities/Clients †¢ Completely Automated Process The E-tender process in clients’ comp uters are all automated, the list of bidding contractors is sorted out in the ascending order from lowest price to the highest. †¢ Shortens Procurement Cycle Most of the clients hope that the procurement cycle be short, the E-tendering is best able to achieve this requirement. Economical and Environment Friendly As E-tender system required minimum paper, all information is stored in the computer for processing and retrieving. A computer can be used for 3 to 5 years, as for traditional tendering documents it is disposed once it is used. †¢ Greater Transparency The E-tendering website is open to all the authorized and registered members; hence all of them are able to see the data posted in the website with great transparency. †¢ Improvement in work culture in the departments It create a more friendly and conducive working culture in the departments, as less miscommunication between staff occur. System aided Evaluation process After the closed of tender, the E-tender sys tem will automatically aid in evaluating the most suitable tender. It cut down the time for evaluation. †¢ Minimize Human errors Most of the process is carry out in the computer, hence minimize human errors. †¢ Minimal Storage Space A computer is all you need for storage of all the tendering document. Printing out of hard copy is only needs required. †¢ Change in Perception The perception of a company will be changed as E-tendering is implemented for a Client. It will become a more progressive and proactive organization. Lesser hassle of communication and administration Communication between client and contractor, among staff will be much easier through computer and administration will have lesser hassle. The cons or disadvantages of using e tender †¢ Cost The initial cost to set up the computer system can be quite costly. As E-tender required the purchase of expensive hardware and the necessary software. †¢ Staff The company need to employ staff competence in the use of e-tendering system or train up their existing staff to use the e-tendering system.Security of the e-tendering system – An effective and secure e-tendering system needs to make sure that any communication that passes through the system is secure and safe. As all the data are passing through the open networks such as the internet. Care must be taken to ensure that all the information passed between tenderers and the Client be treated as confidential. The major risks are that confidential information transmitted over opened networks may be exposed to or altered by malicious parties. There is also the risk of malicious parties generating false messages, impersonating other parties or denying that messages have been emailed. . How to overcome these limitations †¢ Cost Construction Company can get a loan from bank to purchase the e-tendering system, through the saving of the e-tendering process; soon the cost would be recovered. †¢ Staff Company can directly employ e-tender system competence staff to from the employment market; alternatively can send their staff to be trained to use the system. Security – One of the major problems of e-tendering is to prevent the unauthorised usage of the e-tender account. The following are a few new computer technologies in the market which are capable of overcoming these problems. †¢ BiometricsBiometric verification of two authorized users can be used in for tender opening process. This method is using finger print of any two authorized individual; the web page will not be able to open if two fingers print doesn’t match. This appliance also helps to establish that user remains physically present when Tender opens. [pic] Figure 4. – Biometrics appliance †¢ Role Base Access This will only allow access to website on the basis of rights allocated to an authorised User or Group of Users. This ensure that Tampering by unauthorized person become not possible. The existing Orga nization hierarchy also can be mapped into the system. pic] Figure 5. – Role Base Access appliance †¢ Time Based Access The system ensures that no activity can be carried out before due date & Time for e. g. Tender cannot be opened even by authorized User before due date. Server Time cannot be tampered as it is mapped to National Standard Time Server. [pic] Figure 6 – Time Based Access Security System With all these security tools in place to ensure security of the website, the usage of e-tendering is getting more and more secure nowadays. 5. Scope of future of e-tendering – Cloud computing The future e-tender is by using Cloud computing. Just what is clouding computer?It is not sitting among the cloud to do the job, it is instead of using our own server to store data, cloud computing is using cloud server for storage of data and retrieving from them. The focus is on the website and not the computer hardware. When the data is needed for large processing, it can be scale up as much as one can instantly and once work done it is released back to the cloud. The working principle is like using the computer power from the cloud instead of using the company’s own computer hardware. It is just like payment for paying for electricity and gas instead of having our own generator and having a large gas storage tank.Cloud computer is also like hiring a car to travel instead of buying a car. The advantages of using cloud can be listed as below: †¢ Scalability – Glow and shrink as and when you wanted. †¢ Instant – It can be turn on and off anytime any place you like. †¢ Economical – Pay for the time you use and there is no need for the hardware and it is time saving. In other words it is pay as you use [pic]Figure 7. – Cloud computing system (Source from Google cloud computing image) 2. 6 Types of Cloud computing There are three types of cloud computing in the market: namelyInfrastructure as a servic e (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS), it has his advantages and disadvantages. †¢ SAAS-Software as a server – Each offers a different level of user flexibility and control. Saas allows users to run existing online applications. It is the easiest way of using, where off-the-shelf applications are accessed over the Internet. The advantages are Free or paid via subscription, it is accessible from any computer and able to facilitates collaborative working. However its business generic applications may not always suitable for their own business use. PAAS- Platform as a server – Allows users to create their own cloud applications using supplier – specific tools and languages. It provides environment and tools for creating new online applications. Eg. Google has Google App Engine which enables a user to build and host web application on the same system, which no need to worry about hardware. Micro soft has a Window Azure Platfor m. Salesfore has a website called Force. com which can build up and host for free. The system can be rapidly development at low cost and used Private or public deployment.However it limits developers to provider languages and tools and it also have the risk of vendor lock-in. †¢ IAAS- Infrastructure as a server – Allows users to run any applications they are please on cloud hardware of their own choice. Figure 8 – The interrelationship between the Cloud Clients and the three types of cloud computing Cloud computer deployment models [pic] There are four forms of Cloud computing applications: Public cloud Public cloud applications, storage, and other resources are made available to the general public by a service provider. These services are usually free or offered on a pay-per-use model.Generally, public cloud service providers like Microsoft and Google own and operate the infrastructure and offer access only via Internet. Other means of direct connection is not po ssible. Community cloud Community cloud shares infrastructure between several organizations from a specific community with common concerns for example security, compliance, jurisdiction, etc. , whether managed internally or by a third-party and hosted internally or externally. The costs are spread over fewer users than a public cloud, but it is more than a private cloud, so only some of the cost savings potential of cloud computing are realized.Hybrid cloud Hybrid cloud is a composition of two or more clouds; it can be private, community or public. It can remain unique entities but are bound together, offering the benefits of multiple deployment models. By utilizing â€Å"hybrid cloud† architecture, companies and individuals are able to obtain some degrees of fault tolerance combined with locally immediate usability without dependency on internet connectivity. Hybrid Cloud architecture requires both on-premises resources and remote server based cloud infrastructure.The disadv antage of Hybrid clouds is that it lacks the flexibility, security and certainty of in-house applications. Hybrid cloud provides the flexibility of in house applications with the fault tolerance and scalability of cloud based services. Private cloud Private cloud is cloud infrastructure operated solely for a single organization, whether managed internally or by a third-party and hosted internally or externally. Undertaking a private cloud project requires a significant level and degree of engagement to virtualize the business environment, and it will require the organization to re-evaluate decisions about existing resources.When it is done right, it can have a positive impact on a business, but every one of the steps in the project raises security issues that must be addressed in order to avoid serious vulnerabilities. The major disadvantage is because users â€Å"still have to buy, build, and manage them† and hence do not benefit from less hands-on management essentially the economic model that makes cloud computing such an interesting concept. 3. 0 Conclusions In conclusion, this paper finds that e-tendering has many pros and cons in the system. However we can see that the pros have exceeded the cons, i. e. he advantages are far more than disadvantages. With the breakthrough in computer technology and the advancement of science, the various problems face by the user in e-tendering now will be easily overcome very soon. As the construction industry in Singapore is one of the major industries that contributed to the nation building and giving the most impact to the economy, the benefits that brought by the e-tendering will definitely benefit the Construction Industry and Singapore national economy as a whole. However new problems may also appear and these need to be overcome continuously to bring about advancement of the system.Eventually all the other industry will be able to benefit from the achievement. 4. 0 Recommendation In view of the current situ ation in Singapore construction Industry, only the government is using e-tendering in a wide spread scale. I would like to recommend the government to initiate and set up an e-tendering system similar to the current GeBIZ system to serve the Singapore private Construction sector. The Singapore government has more than 10 years experience in the e-tendering system, they should have no problem in setting up an equal if not better e-tendering server than the Government e-tendering GeBIZ.Since setting up an e-tendering need a large initial capital investment, as a financially strong Singapore Government this should not pose any problem, moreover it will eventually benefit the economy of Singapore. In order to fully harness the benefits of e-tendering system, the main contractors must adjust and make changes to their company itself to equip with the necessary skills and resources for the e-tendering system. Contractors are recommended to train their staff to be competent in the use of e- tendering system. Companies may also engage professional consultants or experts to set up e-tendering in their company.As e-tendering has proven to be an advantage for the Main contractor to be the better competitor and increase their productivity and profits, I strongly believe that in the years to come, e-tendering will be used both by the private and government construction tendering in Singapore. 5. 0 References Bett. D. Black. P. Christensen. S. Dawson, E, Du, R. , Duncan. W. , et al. (2006). Towards secure and legal e-tendering. Journal of Information and Technology in Construction, XI. 89-102 Bourn J. (2002). Better Public Services Through e-Government. London, National Audit Office (NAO). http://www. nao. org. uk/news/0102/0102704. aspx Baldwin, A. N.Thorpe, A and Carter, C (1999). The use of electronic information exchange on Construction alliance projects. Automation in Construction. 8(6). 651-662 CRC Construction Innovation, 2006. e Tendering: Security and Legal Issues Ti ndsley G. & Stephenson P,. 2008 E-Tendering Process with Construction: UK Perspective Tsinghua Science & Technology, Bol. 13, 273-278 B. Kumar and J. C. P. Cheng (2010), Cloud Computing and its Implications for Construction IT, Computing in Civil and Building Engineering, Proceedings of International Conference. W. TIZANI (Editor). 30June – 2 July, Nottingham, UK, Nottingham University Press, Paper 158. P. 31Akintola,A. A. (2011). A survey of the State of the Art of E-tendering in Nigeria. Journal of Information Technology inConstruction, 16. 557-576. Al-Maadeed, S. (2011). Multi-evaluatins of Tenders in E-tendering System. Internatinal Conference on Technology and Business Management. 3. 201-207. Singapore government's one-stop e-procurement portal http://www. gebiz. gov. sg/. Central Government Autumn 2001 – Paper free-tendering – a 21st Century alternative – Public Service. Website http://ww. publicservice. co. uk/article. asp? publication=Central%20Go vernment (Accessed 25/06/2012) Building and Construction Authority Singapore http://www. bca. ov. sg/ ———————– 12. Tender Audit & Storage 11. Vender Registration & Rating 1. Tender Notice 10. Tender Award 2. Tender Promotion E-Tendering Cycle 9. Negotiation 3. Tender Document 8. Tender Evaluation 4. Pre Bid Meeting 5. Bid Submission 7. Tender storage & Opening 6. Payment Gateway Cloud Clients Web browser, mobile app, thin client, terminal emulator, SaaS CRM, Email, virtual desktop, communication, games, †¦ PaaS Execution runtime, database, web server, development tools, †¦ IaaS Virtual machines, servers, storage, load balancers, network, †¦ Figure 9. – The cloud computer models (Source from Google cloud computing image)