Are cell Phones a Health Hazard?

Are cell Phones a Health Hazard? With the increasing of mobile phones' functions, people rely more and more on them. The lower price also enables the mobile phone to become people's daily necessity. Now even many students have their own mobile phone. People began to worry about the cell phone which will do harm to our health. But why people become worried about that? There are some speculates that cell phone might potentially threaten human being's health. Mobile phones can emit radiofrequency energy (radio waves), which is constituted by non-ionizing radiation.Things closest to the cell phones will absorb this energy. According to the Cellular Telecommunications and Internet Association, as of 2010, there were more than 303 million subscribers to mobile phone service in the United States, which is nearly three times than the 110 million users in 2000. Globally, the number of mobile phone subscriptions is estimated to be 5 billion by the International Telecommunications Union. The nu mber of mobile subscriptions has already increased quickly.  (Cell Phones and Cancer Risk, 2012)The chart below (Chart 1) shows the number of mobile Internet users, including the prediction of the number in 2013. Over time, the amount of time of each phone call, as well as the number of people using the mobile phone has increased. Mobile phone technology has also had a very big change. Chart 1 Chart1: US moblie Internet users & penertration, 2008-2013 (millions and % mobile phone subscriers) To my way of thinking, cell phones will really have a health hazard. RF is a potential threat to human body.Radiofrequency energy (RF) is a form of electromagnetic radiation. Electromagnetic radiation can be defined into two types: ionizing (e. g. , x-rays, radon, and cosmic rays) and non-ionizing (e. g. , radiofrequency and extremely low-frequency or power frequency). (Cell Phones and Cancer Risk, 2012) As we know, all of the creatures and plants, including humans, are exposed to ionizing rad iation and non-ionizing radiation during the whole period of evolution. So recently the society began to worry about the potential harm of RF from cell phones which may cause brain cancer.A series of studies began to look at the relationship between cell phone usage and brain tumors. If cell phone will bring a negative effect was a controversial topic, and the opinions on this topic are extremely different. Some people hold that cell phones are nothing to do with the health problems, since the non-ionizing radiation from cell phones is typically safe to the human body. A low level of radiofrequency energy is a kind of non-ionizing radiation, and it is different from high levels of radiofrequency energy that produces negative health effects by heating tissue.(Radiation-Emitting Products, 2012) Therefore, it can say people exposed to low level RF which does not heat tissues in human body are not necessary to worry about with cell phones. Although low level RF is safe doesn’t me an that the potential damages do not exist. Firstly, our brain is able to absorb the electromagnetic radiation at radio frequencies that emitted by mobile phones, so if we use mobile phones for a long time, which will increase the hazard of brain cancer to a great extent. So this is a long-term effect. Secondly, cell phones are becoming more advanced, and the inner structure of cell phones has had a great change.Cell phones have come to our daily life with more functions, which may have unknown effects. A recent study showed that when people used a cell phone for 50 minutes, brain tissues on the same side of the head metabolized more glucose than that on the opposite side of the brain. (Cell Phones and Cancer Risk, 2012) It means that using cell phones can change some tissues of human body, although the outcomes have not been deemed good or not. Another negative effect is that talking through cell phones when driving will increase the risk of traffic accidents.There were nearly 80 m illion people who own cell phones, and surveys indicated that 85 percent of these owners use phones while driving. (Williams & Analyst, 2002) According to the journal's publisher, the Human Factors and Ergonomics Society, there are 2,600 deaths and 330,000 injuries in the United States every year because of mobile phone distraction. (Britt, 2005) Drivers talking on cell phones will have their attention distracted. As a matter of fact that only 80% of their attention can be paid when they are talking to somebody. And speaking requires more attention than listening.In a conversation, if a driver is more eager to talk to others than to listen, the greater the distraction he has. It is said that drivers use cell phones when they are driving just look but don’t see. There were two different experiments associated with professor of psychology Dr. Amit Almor. (Science Daily, 2008) One experiment needed the participants to test the visual shape on a monitor, and the second experiment required participants to do a visual task while listening to a story that had been prerecorded and then the participants were required to tell their feeling about this story.In the end, the attention level of these participants had been measured. People found that they were four times more distracted when people were speaking than when they were listening. It came to a conclusion that speaking demands more brain’s resources than listening. People are used to communicating face-to- face, so if they were talking while driving, they will imagine the conversation in their brain, and they have to try to remember what they have been talking and how to respond in a right position. Hearing loss is also a big health hazard.People who use cell phones for more than one year acquire hearing loss problems, according to research presented at the American Academy of Otolaryngology-Head and Neck Surgery Foundation's Annual Meeting & OTO EXPO in Washington, DC. Otherwise, the study found tha t people who used mobile phones more than one hour a day were more likely to suffer from hearing problems. (Robert, 2007) Obviously, long-term use of cell phones will have a great impact on hearing, which is mostly a negative impact. Using cell phones too long may damage our inner ear and bring about a high frequency hearing loss.High frequency hearing loss means that people may feel difficult to hear consonants such as s, f, t, and z, but they can hear vowels generally. Therefore, although people can hear muffled sounds, they unable to figure out what people exactly say. Not just talking too much through cell phones may cause hearing loss, but listening to high decibel music is also producing a big damage to hearing. People now would like listening music with their phones wherever they go, such as in the train, because it is very noisy when taking a train, so people always prefer listening to high decibel music that they can enjoy the clearer music.If some symptoms such as ear ring ing, ear warmth, and the ear fullness have arose, which are warning signs that your hearing is in danger. What are the reasons these symptoms have occurred. The possible cause is the electric-magnetic-frequencies, which emit a magnetic field greater than 3 milli-gauss from many cell phones.The Environmental Protection Agency has announced that electric-magnetic-frequencies greater than 3 milli-gauss may do harm to human health. (Robert, 2007) Naresh K. Panda, MS, DNB, chairman of the department of ear, nose, and throat at the Post Graduate Institute of  Medical Education and Research in Chandigarh, India, and researcher for a study. He and his colleagues performed experiment. They texted 100 people, at the age of 18 to 45, who had used cell phones for at least one year, and according to length of use, they divided this people into 3 groups. One group had 35 people, who had used cell phones for one to two years, and another group of 35 had used cell phones for two to four years, an d the final 30 people had used them for more than four years.Those who used the mobile phones for more than four years suffered a greater degree of hearing loss in their right ear, the ear often listens through the phone, than those who used the mobile phone for one to two years. (Doheny, 2007) As well, using cell phones too long will hurt our eyesight. Numbers of people use cell phones every day. We can do many things on our cell phones: sending text messages, reading emails, surfing the web, and even finding the driving directions. It’s so amazing that we can do all of this work just in a device which can be held in one hand.However, lots of problems are coming with this convenience. Reading such the really small text on the phones will cause problems. Not only for the tiny letters in such a small screen, but also people have become accustomed to holding the phone closer to their face than they need to. Reading from your phone forces your eyes to focus in a way which is muc h different than before when people usually read from paper. It is also harmful with your eyes’ vergence, which is the simultaneous movement of both eyes in opposite directions to obtain or maintain single binocular vision.Although your eyes are designed to adapt to the circumstances more easily, many people have become accustomed to reading from their cell phones all day long. In the long term, not only can this habit lead to headaches, but also eyestrain, dry eyes, and blurred vision. According to Dr. Jeffrey Hankin, an optometrist, people are pulling their smart phone four inches closer than normal reading distance could cause problems. (NBC25 News, 2011) This is always accompanied by a headache while people just feel tired and maybe have a little difficulty on focusing.Sometimes the blink rate will slow down and the eyes are dry. These symptoms cannot be ignored. It is saying that your eyesight is becoming weaker. How cell phones damage our eyesight? We are in the environ ment full of radiation and electrical signals , at the same time, human body was being attacked by hundreds of signals every second. It is affecting all our body parts, but we have not aware of it yet. â€Å"The wavelength of wireless signals (which is about 2 to 2. 5 cm) used for mobile phones and other wireless terminals matches with that received by the human eye.The dielectric constant (absorption capacity) of eye tissues is around 70 which is greater than unity (above 50). This means that the eye can absorb electromagnetic energy very quickly,† explains Dwivedi. (Cell phones can damage eyes, 2010) So it comes out a conclusion that the problem is not the energy absorbs by the eye, but the heat from the energy absorbed by the eye cannot get transmitted out of the body. Moreover, cell phones have a strong relationship with human mental health. People always take cell phone with them all the time, no matter where they go.They play games, listen to music, watch videos, and ch at with friends. It seems like that we can't live without cell phones, especially children. More and more children at 12 and 13 ages have their own cell phones. Those children who are addicted to cell phones spend most of time on their phones, like talking, texting or playing games. Their parents are beginning to be concerned that the children are unable to do some normal activities without their phones. They often skip classes and lie to relatives to get more money to buy phone cards.It these situations, cell phones are just like the drugs which make the children gradually lose themselves. What’s more, lots of students even play cell phones during class. While teachers are speaking in front of students, students are texting or playing games in their seat even without any covers. The other mental problem is that cell phone is tending to cause depression and sleep problems in young people now. Young people who use cell phones heavily also complain more about sleeping problems, pressures and other mental health problems, according to researchers at the University of Gothenburg, Sweden.(Pedersen, 2012) Researchers made a questionnaire survey towards 4,100 young adults at the ages of 20 to24 and interviewed 32 heavy users of information and communication technology. The findings interpret that the use of mobile phone has a close relationship with pressure, depressive symptoms and sleeping disorders. The researchers could not be sure of the origin causes, but what we can speculate is that people with depression or sleep problems perhaps get access to cell phones more than others. Here is more other evidence. The University of Tokyo’s researchers investigated nearly 18,000 young people in in high school in Japan.In order to estimate their depression, anxiety and even thoughts about suicide, the participants were required to answer some specific questions. Participants also reported how often they spoke on their cellphones or sent emails after going to bed and how many hours they slept at night. The findings tell us that children in different countries with different cultures have similar problems are related to similar reasons. As a whole, cell phones are closely integrated cell phones into our lives, yet they have health hazard for our daily lives. We should use them in a proper way.

“A Question of Torture” by Alfred McCoy

â€Å"In April 2004, the American public was stunned when CBS Television broadcast photographs from Abu Ghraib prison, showing Iraqis naked, hooded, and contorted in humiliating positions while U.S. soldiers stood over them, smiling†. (p.5)Here Alfred McCoy starts his narration. His book â€Å"A Question of Torture† is labeled as a penetration study of fifty years American participation in torture propagation, research and practice. The book reveals degrading and inhumane treatment, cruelty and injustice in US history intensified by tragic personal case studies and experiences.The author deepens in why the tortures were sued, where they were implemented and what the consequences were. It is known that CIA had spent millions of dollars on torture research and the author writes that it combined self-inflicted pain with sensory deprivation with the eternal purpose of creating revolutionary psychological approach. The goal was to develop the first innovation in torture: â⠂¬Å"Still, if genius is the discovery of the obvious, then the CIA's perfection of psychological torture was a major scientific turning point, albeit unnoticed and unheralded in the world beyond its secret safe houses†.   (p.7)The primary techniques in torturing were hooding, isolation, extremes of hot and cold, hours of standing without opportunities to move or to change body position, manipulation of time. In such a way CIA had managed to destroy victim’s senses and his personal identity. All these techniques are claimed to have been used in Vietnam, Iraq, Iran and Central America. For example, Washington is argued to refer to torture in CIA’s prisons and torture-friendly countries.Nevertheless, information obtained through torturing is really worthless as victims were ready to acknowledge their fault even if they were not guilty. McCoy says that the agency used electric shocks and recruited peopled like, for example, Kurt Plotner. The author concludes that t he simplest and cheapest methods work the best and, what is more awful, public accepted them more than physical violence.Book DiscussionI think that the book â€Å"A Question of Torture† is really shocking and impressive study as the author reveals the most contradictive and painful pages of American history.Nevertheless, the book contributes historical filed as McCoy tends to provide neutral and realistic examples how tortures were used by CIA and where they were used. The author frames historical development of tortures stressing they are sanctioned. He seems to be very concerned with the diminished standards of American nation.However, I agree with McCoy that tortures are rarely affective and it is simply a like looking for a needle in haystack. The book teaches us that once torture is implemented, it results in mass tortures as, for example, tortures in Argentina and Chile during their ‘dirty wars’. Moreover, mass tortures are linked to increased rates of jud icial killings.

High Performance Concrete Reinforced with Glass Fibres Essay

High Performance Concrete Reinforced with Glass Fibres - Essay Example In order to achieve performance-related properties specific to performance in HPC, attention should be directed to the combination of performance requirements (such as strength limits and permeability) and prescriptive requirements (such as air content limits or dosage of supplementary cementing material) (Ferraris and Lobo, 1998). Depending on the HPC mixtures examples of HPC include High-early-strength concrete, high-strength concrete, high-durability concrete, self-compacting concrete and reactive-powder concrete. High-Early-Strength Concrete (HESC) High-Early-Strength Concrete (also known as fast-track concrete), achieves its specified strength at an earlier age compared to normal concrete. This earlier age is the time period in which a specified strength should be achieved and may range between a few hours (or even minutes) to several days. Although it can be achieved using traditional concrete ingredients and concreting practices, the production of HESC will sometimes require s pecial materials or techniques. Depending on the age at which the specified strength must be achieved and on job conditions, one or a combination of the following can be used in the production of HESC: type III or He high-early strength cement, high cement content, low water-cementing materials ratio, higher curing temperature, higher freshly mixed concrete temperature, silica fume, chemical admixtures, special rapid hardening cements, insulation to retain heat of hydration, and/or steam and autoclave curing. High-early-strength concrete is used for prestressed concrete to allow for early stressing; precast concrete for rapid production of elements; high-speed cast-in-place construction; rapid form... High-Early-Strength Concrete (also known as fast-track concrete), achieves its specified strength at an earlier age compared to normal concrete. This earlier age is the time period in which a specified strength should be achieved and may range between a few hours (or even minutes) to several days. Although it can be achieved using traditional concrete ingredients and concreting practices, the production of HESC will sometimes require special materials or techniques. Depending on the age at which the specified strength must be achieved and on job conditions, one or a combination of the following can be used in the production of HESC: type III or He high-early strength cement, high cement content, low water-cementing materials ratio, higher curing temperature, higher freshly mixed concrete temperature, silica fume, chemical admixtures, special rapid hardening cements, insulation to retain heat of hydration, and/or steam and autoclave curing. High-early-strength concrete is used for prestressed concrete to allow for early stressing; precast concrete for rapid production of elements; high-speed cast-in-place construction; rapid form reuse; cold-weather construction; rapid repair of pavements to reduce traffic downtime; fast-track paving; and several other uses. In fast-track paving, use of HESC allows traffic to open within a few hours after concrete is placed.

7 SHORT ANSWER QUESTIONS ONLY Assignment Example | Topics and Well Written Essays - 750 words

7 SHORT ANSWER QUESTIONS ONLY - Assignment Example (PLEASE FEEL FREE TO USE YOUR OWN RESOURCES) 1. What is orthography and how does it differ from phonetic spelling? Explain why linguists use a phonetic alphabet to represent speech sounds instead of regular spelling. Include specific examples in your answer. (125 WORDS) Orthography means literally correct writing and it refers to the rules and conventions of the written language. It includes the way that letters are used to spell out a word, punctuation, and the use of capitals and lower case letters, as for example the use of capital letters for all nouns in German, but only for proper nouns in English. Orthography alone is not a good system for linguists because it does not represent accurately the actual sounds that are produced in spoken language. Two speakers from different parts of the United States might pronounce the same word differently and this is not recorded in orthography. A phonetic alphabet has one symbol for each sound and this allows accurate analysis of sounds. Suprasegmentals are a linguistic feature that can be found in the spoken language. Linguists look at the small segments of speech, such as vowels, consonants and syllables and analyze how these are formed and how they fit together into words and phrases. Suprasegmentals are features that transcend these tiny pieces and range over several syllables. An example of a suprasegmental is the way that intonation and stress patterns operate. It is important to identify these features because they can change the meaning of an utterance, for example a rising intonation can mean a question in English whereas a flat or falling intonation is a statement. Stress on a word can mean emphasis. The word â€Å"desert† has different meanings, depending on which syllable is stressed. Answer the following questions in your own words. Your answers need to be complete enough to demonstrate mastery of the lesson objectives. A brief paragraph (5 sentences)