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Mormon. Sexuality is an area of life that brings on risk, with the potential for positive or negative outcomes, success or fa
Mormon
Sexuality is an area of life that brings on risk, with the potential for positive or negative outcomes, success or failure. This is no more or less true for adolescents. The important difference is that teens do not yet have well-developed risk assessment skills. As in any area of life, if we want teens to be psychologically healthy, we want to promote their learning. This also holds especially true for their sexuality. In our culture, sex is still viewed as a taboo subject. I am interested in teen sexuality and how I might raise a sexually healthy teen, because I have a teenage son.
One parental concern might be the influence of TV and music TV, on teens. Researchers have been investigating this idea. In, “What teens have to say about sex on TV and in music videos” by Scott Simon of Saint Paul Pioneer Press (06/02), he reports what Joseph Shapiro and a group of teens had to say. The Kaiser Family Foundation put groups of 12 –15 year old teens in a room to listen to what they had to say about the sexually explicit TV and music videos on TV today. Mr. Shapiro and Dr. Jane Brown observe these teens.
Dr. Jane Brown, of University of North Carolina, is studying how sex in the media affects teens. She argues that it is very apparent that the teens are developing strong senses of morality. Teens want to be good; they strongly desire to act appropriately. She theorizes that teen sexual attitudes are greatly influenced by the amount of TV they watch.
After the teens viewed a popular Britney Spears video, the teens shared similar opinions. They viewed the skimpily dressed singer, as she went from one male singer to another, grinding her way across the stage. They used words such as gross, nasty, and disgusting to describe Spears’ actions and her clothing. Shapiro and Brown observed that the teens were very judgmental about what they viewed on TV.
Next the teens watched a scene from a sitcom called “Clueless”. In the scene the actress was conversing about who was going to lose their virginity first. The teenage actress was clearly upset, that another teen peer was going to lose her virginity before her. It was perceived as cool to have sex. The actress was upset that her not-as-popular teen peer was going to have sex before her.
Following the clip, the focus group, commented. They felt that the message being sent was that sex is cool, that if they were not having sex, they should be embarrassed. They felt that it was humiliating that the other actresses were laughing at the teen that had not had sex. Berk speaks of the imaginary audience (page 375), that teens always see themselves as on stage. Teens are extremely self-conscious, and avoid embarrassment. Teens would go to great lengths to avoid humiliation, and this scene was clearly showing that. The actress would have rather had sex to avoid peer humiliation.
Later, the focus group discussed the scene from the sitcom targeted to 14 & 15 years old, called “Dawson’s Creek”. The scene was about two teens who were going to have sex for the first time. The teens were not naïve to realize that the TV show was setting up a ‘perfect’ scenario for the first romantic experience. They noticed that the TV show did not mention STD’s. Interestingly, they were not surprised. They commented, “Sex sells”. The teens were perceptive enough to know that TV is a business, and business means money.
Parents want to know, are kids more likely to have sex, if they watch TV? Researchers cannot answer that, exactly, but what they do say is, the more you see the same thing over and over again, the more likely you are to believe it. For instance, a teen girl may have never kissed a boy, but the message of how to do this, has been imprinted in her memory from repeatedly seeing it on TV. She can than model a kiss, and not even know where she learned it from.
In the article, “Teens first sex is at home”, USA Today (09/02), a survey showed that teens were having sex in their homes, or at their partners’ home. This comes as a surprise to many parents. It should not come as a surprise, with the arrival of puberty and hormonal changes, we see the increase of sexual activity. Berk reports that American parents give their children little guidance about sexual information, and that the parents do not converse about sex in the presence of teens (page 360). With teens watching Prime-Time TV and MTV with high sexual content, it is even more important to speak to our kids about sex.
Teens watch approximately 3 hours of TV today, and they see sex glamorized.
Teens are getting mixed messages, at school and at home they are told to stay away from sex. They are taught the dangers of sex, STD’s, AIDS, pregnancy. Peer pressure is at its highest during adolescence. Adolescents mirror their social and emotional environments. Berk teaches us about a cognitive distortion, called the personal fable (page 375). This is easily explained as the “not me” opinion of themselves. Teens get such inflated opinions of themselves they don’t ever think that bad thing can happen to them. TV does not include the dangers of the sexual behavior. Approximately, 50% of teens do not use contraceptives (page 361). Since teens have the highest rate of STD’s of any age group, and TV does not promote sexual education, this message could be extremely dangerous!
In the article, “Teens close to their mothers are less likely to have early sex, study shows” by Tom Majeski of the Saint Paul Pioneer Press (09/02), Majeski reviewed longitudinal studies focusing on the relationship between mothers and their teenage children. More than 5000 teens were followed for over a year. The studies show that the more involved a mother is in a teen’s life; the age of sexual activity is postponed.
Researchers also found that mothers that spoke with other parents influenced the delay in sex. They explain it as, the more you know what is going on around your teen, the more you can influence them positively. Since teens have not mastered combinatorial thinking, they may make the wrong decision. The more a teens’ parents are involved, the greater their awareness of their child’s decisions. This may make the teen more conscious of their actions, for fear of disappointing their parent.
The study showed that mothers were more uncomfortable talking to their daughters than to their sons about sex. Berk might explain this as gender typing (page 401). Society tends to be more relaxed with male sexuality. Society is very harsh on female sexuality, thus this may reflect the way a parent speaks to a teen. It seems that our society sends a message that it is okay for males to be having sex, but it clearly views teen females having sex, very negatively.
Joseph Plambeck of The Tribune wrote a similar article, “Teens who are close to mothers delay having sex, report says” (09/02). The study similarly stated that mothers who were close to their teenage children show a higher delay in sex, than those who were not. Again, the study agreed that the parental involvement with other parents was a strong influencer. The study stated that mothers needed to speak with their teens about their own values.
Education was an important factor stated Plambeck. An interesting finding was that girls whose mothers were college educated, where less likely to become sexually active. I find this interesting, since my son of 14, is actively watching his mothers’ college education.
Parental guidance is most influential, writes Daniel Wood of The Christian Science Monitor, in “Teens, Sex and the Power of Parents”(09/02). This is an overall consensus between all the articles chosen. The article states that when it comes to sex education and teens, along with parental involvement, the way parents speak to their children about sex is also highly important. Warm, open households are the most successful.
The study also says the sex education needs to start as early as the elementary level. That getting parents values into their children’s lives earlier was important. As mentioned earlier, the influence of TV brings sex into our children’s lives earlier and more explicitly, thus, the reason for earlier communication on sexual values. Parents who had high expectations of school, and also having stricter rules made a difference. Berk agrees that warm guidance and rules are positive, both, which are features of the ideal authoritative style of parenting (page 269).
The study reminds us that at this time when a teen is searching for autonomy and identity, parents tend to back off. As a teen is gaining a sense of individuality, the desire for their parents input is less welcomed. This is a crucial time to have a balance in the home. Wood, of The Christian Science Monitor, states that family meals could help bring a more harmonious environment. Erik Erikson refers to this the psychological conflict during these teen years, as identity versus identity confusion (page 390). Erikson said that successful outcomes early, lead to positive resolution.
Teens are battling to understand sex during a period when teenage sexuality is changing. An increasing number of teenagers in the United States have sexual intercourse. If we want adolescents to be sexually healthy, we have to promote their learning to act in their own best interests. With TV, and peer influences being stronger than ever, the need for parental involvement increases. Sexuality can be easier for all, if parents can become more aware of their teens sexuality, and are prepared to give them help or advise when needed. They can help their teen to develop the proper skills and awareness they need to make sexually healthy choices during adolescence.
Bibliography:
Mores, laws and folkways
Mores, laws and folkways
Societal norms which include mores, laws, taboos and folkways are agreed upon rules and expectations that an individual is supposed to observe and behave according to in a given culture. Norms vary from one culture to another, some thing might be considered as a norm in one culture and in others it is not (Macionis, 2009). For example, shaking hands as a form of greeting in most of the African country shows a lot of respect. Whereas, in Asian countries you are not supposed to shake hands with your elders as a form of greeting
Folkway is said to be socially learned behaviours that are looked upon but which do not necessarily convey any moral significance. These are norms that help individuals interact with the other members of the society towards a harmonious living. Folkways for individual cultures arise from continuous repetition of an act that helps in the shaping of human behaviour. Unlike like is the case with other societal norms, the defiance of folkways carries no serious consequences. A common folkway is the dress codes adopted in different regions and countries (Pauer-Studer, 2008). Muslims dress in Hijabs and long dresses as a folkway but if a Muslim decides to dress in a short dress, no moral rule or laws are broken (except in strict sharia nations maybe).
Mores are significant norms that govern the right or wrong and control the behaviour of an individual. They are not necessarily written set rules to govern an individual but are behaviours that are generally accepted and what society follows in day to day life. Religious rules are example of mores (Macionis, 2009). Catholic clergy are nether expected to break their chastity vows nor are they supposed to get into matrimony and when they behave in a way contrary to this dire consequences are met on them, including excommunication from the society.
Laws are well raid down set of rules that have to be observed and enforced by law officials. Violation of these norms leads to prosecution in law courts. Driving while drunk is an offence which will land you in jail or be fined for violating that law.
When using your mobile handset in a public place you should not shout, level your voice such that you will not be disturbing the others. Shouting over the phone will be violating the folkway. When you violate that norm you feel you are not conforming to the normality of the society On the other hand the people around you will despise you for your behaviour, some of whom will not tolerate your behaviour and try to stop or tell you to lower your voice.
Normative conduct theory is clearly shown in the above example where by the behaviour of talking loud might have been as result of two conflicting beliefs. This might be because one was thinking he/she is in a noisy surrounding and the person on the other end might not hear them. The surrounding people’s approval of situation about that particular behaviour shows how the individual should behave (Pauer-Studer, 2008). Watching other person talk loud over the phone, a society member might pick up on the norm that they are supposed to talk loud in public places
Control theories exist due to lack of socialization, this leads to lack of self control as expressed in that example of speaking loudly over the phone. Individuals who are always overconfident of themselves will exhibit this behaviour and are more likely to violate folkway norms. Control theory considers the individual decision making being as the reason behind such behaviour (Pauer-Studer, 2008).
In conclusion we can say that society behaviour is directly dictated by the norms that are observed by it. That explains why we have different behaviours between different cultures as the norms are not the same.
References
Macionis, J. J. (2009). Society: The basics. Upper Saddle River, N.J: Pearson/Prentice Hall.
Pauer-Studer, H. (2008). Norms, values, and society. Dordrecht: Kluwer Academic Pub.
Adhesive Bonding in the aircraft and automotive industry
Adhesive Bonding in the aircraft and automotive industry
Adhesive bounding of aluminum components in the aircraft and automotive industry are rapidly replacing many conventional methods of joining two parts togheter. Adhesives bonding is a process where a monomer compound is applied in between joints and is chemically allowed to transform into complex long chained polymers which interlock the mating parts by inter-atomic bounding and diffusion of the adhesive into the adherents. In most common uses, bonds are permanent, such as the thermosetting adhesives, and require machining in order to separate the mating parts. In other cases, the adhesive bond might be directly related to the operating temperature, as in thermoplastic adhesives, or may contain natural resins and form an elastic bond such as elastomeric adhesives. Adhesives are mostly limited to shear stress applications due to their relatively low peel and creep capabilities and require far more surface area to form a joint then conventional methods, however, their benefits in weight reduction and enhancing ergonomics, as well as their still fairly inexpensive and ability to function in a wide range of environments, are attractive traits which may influence a designer to select such a process.
Adhesives have been long known as the oldest means of joining two parts togheter. In fact, archeological evidences has been found showing the use of natural resins by early man to fasten arrows and spear heads to shafts (3, 170). They also found there first structural use well over three thousand years ago in the construction of the Tower of Babel ( 9, 3). However, it wasn’t until the second World War where great advances where made in structural adhesive bonding which applied to metal to metal structures. Redux, an adhesive conceived in England, was the first ever adhesive used in considerable proportion on the lightest fighter plane of that time, the Mosquito. Following in it’s allied foot steps, the Americans also adopted this process to produce the most effective aircraft of the war, the De Havilland Hornet which used the adhesive to bond the aluminum extrusions to the capped wing spars (4, 41).
Adhesives have since grown considerably and since no one universal adhesive exists up to date, the boundaries are limitless. They can be found in mostly all types of industries, from high tech aerospace to dishwashing machines, and are more and more, replacing conventional ways of fastening joints, namely mechanical fasteners and welding process.
In most cases, monomers are applied to it’s adherent (part to be jointed) and are turned into polymers, which are long chain type molecules, by means of diverse catalyst ranging from heat, pressure or some other chemical compound all depending on the type of adhesive used.
The reason why the bond takes place between the mating surfaces however has taken different theories over the past years. The three most common, principle of diffusion, principle of mechanical adherence and the principal of inter-atomic bonding have been well more developed than other explanations of why adhesive bonds occur.
The diffusion principle states that at polymerization, some of the molecules diffuse in the adherent and consequently, some molecules of the adherent diffuse into the adhesive in order to form a solid joint. The mechanical principal states that, the imperfections on the wetted surface of the adherent serve as to grip the adhesive when it turns into it’s solid polymer state and takes advantage of these imperfections to establish a solid bond. However, this might not help in explaining why perfectly strong bonds are also possible on highly polished surfaces. The third and most generally accepted theory attributes the bonding forces to the fact of the sharing of valence electrons between the newly formed polymer and the adhered material. Some may like to contribute all three factors working togheter as the proper definition of the bonding process( 3, 170) .
Adhesives may be categorized in three groups, thermosets, thermoplasts or elastomers.
Thermosets such as phenolics, epoxies and ureas are adhesives capable of withstanding high shear stresses and are capable of maintaining their properties for a wide range of temperatures. Once cured, machining or extremely high temperatures are required in order to break the formed bond and are irreversible processes. Contrarily, thermoplasts adhesives such as polyvinyls, acetates or acrylics have bond strength variation which is directly temperature dependent and for which at low temperatures, the bond gets stiff and brittle, but at high temperatures, ductile and elastic bonds occur. The third and last classification are elastomers which are generally made of natural or synthetic rubbers and latexes which are highly ductile and deformable adhesives at temperatures ranging close to room temperature ( 1, 402).
Most adhesives are furthermore classified under its ability to cover the entire surface of the mating parts, termed wetting ability ( 8,5). The Washburn equation is generally applied in order to classify the wetting property of the adhesive and is given by:
t = (2h/gcosq) * x2/rwhere
t : rate of filling irregularities
x : length of irregularity
r : capillary radius
h,g : viscosity and surface tension
q : contact angle between adhesive and substrate
Although the basic application are quite commonly simple, where most adhesives today are still spatula applied, automation is quite common and not such a daunting task to perform. The challenge lies in the preparation of the surfaces to be bonded as well as the study of the optimal curing times and temperatures required to obtain the required bonding strengths.
All parts require extensive cleaning with the use of solvents to eliminate any dust or grease deposit, which may interfere with the bonding process. Metals with oxide films are usually grounded and aluminum alloys pickled in alkali baths at temperatures of 170oF up until 10 minutes in order to clean and roughen the surface for the adhesive. Bare hands should never come into contact with the surfaces to be bonded as they will re-introduce grease to the surfaces to be mated (1, 417). As for curing temperatures and times, each vary depending on the type of adhesive used and the required bond strength sought ( 6, 1054). The most common use of adhesives is in shear bearing applications due to their poor resistance to peel, cleavage and tensile stresses (6, 1056).
This is where the challenges arise for the engineer who must design or modify an existing joint in order to maximize the load in a shear plane direction. Although they are limited to these applications, a well-designed joint may sustain an impressive amount of stress. However, most load bearing structural adhesives may have quoted performances rated as high as 50% of their ultimate tensile strength, but as a general rule of thumb, these materials should never be loaded more than 10% of the rated capabilities, which make designers skeptical in using adhesives for long term use applications ( 7, 5 ).
Another problem arises at selection of the adhesive since no universal adhesive exist, each adhesive has its own characteristics for which it may perform at better operating conditions then others and therefor, a quite profound knowledge of the different types of adhesives available is required. Furthermore, design must require high surface finish and quality control performed very closely. And in most instances, the conversion from a mechanical fastener to an adhesive usually requires a considerable larger surface area of jointing ( 9 ,10-13).
So why use adhesives one might ask? Some adhesives today are now capable to cover temperature ranges from -55oC to 350oC with service life of 60 000 hours or 20 years (4, 42). Furthermore, there are several beneficial reasons why adhesives may be preferred over conventional joining processes. For instance, when comparing to welding, adhesive joints do not distort the part close to the bonding area and does not leave any surface discoloration’s, which in turn may require further grinding and then painting. The most notable advantage is the possibility to join dissimilar metals, which is impossible in welding due to a high variation in melting temperatures.
As for mechanical fasteners, the replacement with adhesives induces a reduction in overall weight and serves as a corrosion barrier between a joint made of two different materials. Since adhesives are also less stiff then most fasteners, they also serve as vibration dampers and can easily accommodate thermal expansion of the adhering joints. By replacing rivets with adhesives in structural components, it is also possible to eliminate the stress concentrations formed near rivet holes and therefor prevent unforeseeable stress cracks, which may lead to disastrous failures. In an ergonomic point of view, adhesives do not protrude from their assemblies and go virtually unnoticeable and offer great characteristics in aerodynamic applications ( 9, 9).
Although the alternative of opting for an adhesive joint might be appealing in some circumstances, the economics involved can be quite complex. In general, adhesives are less expensive than a welding or fastening procedure. However, the implementation of adhesives in a mass production might prove to be quite expensive when taking for account the surface preparation requirements, the curing times and temperatures and the expertise needed to evaluate and control these processes. However, many companies have established major savings by using adhesives instead of other methods. The Northrop Aircraft Company stated that their conventional riveting operation of fabricating trailing wing sections cost them closely to1312$ where as obtaining similar strengths by using adhesives cost them 149$ per wing (3, 171).
In addition, the use of adhesives permitted the use of 0.020in thick aluminum sheets instead of the 0.051in sheets minimum requirements for rivets. Hence savings in money and weight ( 9, 5).
Adhesives most important contribution to the automotive industry came in the early 50’s when it replaced the rivets used to hold the brake linings to the shoe. This allowed for a far greater life of the brakes as they could know be run down all the way down to the show, instead of at the rivet heads. Also, created no distortion in the lining due to riveting, created better heat dissipation and reduced the risk of brake failure.
Although many new applications have arisen, they do not contribute an important saving to the automobile producer. Welds are still very present and so are mechanical fasteners due to the requirements of mass production, which can not permit itself of stopping the production line in order to let the structural adhesives cure. However, most of the final assemblies such as the trimmings, the side panel guards, the window rims and other sealed surfaces are joined by adhesion just prior to painting such that when the automobile must be put in an oven for the paint to cure, the adhesives cure also. Some manufacturers do use adhesives to fix the top gears of the transmission due to their low torque capabilities, namely Renault, and the arrival of vehicles made of composite material panels have created the need for an increase in adhesive joints (5, 63-65)
The reason why adhesive technology has developed so much is surely due to this industry in which adhesives plays a crucial role. A typical Boeing 747 is composed of over 1300m2 of adhesive material. The entire fuselage is covered by an adhesive film, which helps in the aerodynamics and the acoustic dampening of the vehicle. Furthermore, apart from the hundreds of sealed joints where adhesives can be found, critical structures such as wing sections, thrust reversers, walking panels, elevators, doors and flaps to name some, are all composed of high resistance, light weight, good fatigue and high acoustics dampening honeycomb structures which can only be assembled with high strength adhesives (8, 258). Up until date, not one adhesive failure has ever been directly linked to a fallen airplane (9, 5) .Helicopter blades consist of plate-to-plate type adhesive bonds which make for a better, more aerodynamic and certainly safer joint then with rivets, which where know to fracture off (4, 44)
As for space travel, no mission in space would have ever been possible without the use of high strength and temperature ranging adhesives which are required to mount the heat shields on the shuttles under side which protect it from flaming up on re-entry into the atmosphere ( 9, 7).
As the cost of life increasingly becomes more expensive, especially when considering the high fuel prices of today, it is no wonder why manufacturers of transportation vehicles try to optimize their product in order to somehow turn out a profit. Some factors, such as weight and drag reduction, may help in turning in some savings, without compromising the overall safety of the consumer. Adhesives have helped alleviate the problem and this can be seen on such a wide scale that the adhesive industry has grown considerably over the years, an estimated 20% increase in production annually (3, 1). And as more composite materials make their appearance and become economically more feasible, so will the appearance of vehicles which will entirely be made of these plastics and will most certainly contain numerous bonded joints which can only be achieved threw adhesives. These days are certainly not far out of reach.
Bibliography:
1.Dr. Jack W. Chaplin, Metal Manufacturing Technology, 1976, McKnight Publishing Company, Bloomington, Illinois, TS 205 C45, Concordia University Librairy.
2.Lawrence E. Doyle, Manufacturing Processes and Materials for Engineers, 3rd edition, 1985, Prentice-Hall Inc., Englwood Cliff, New Jersey, TS205 D64, Concordia University Librairy.
3.Roy A. Lindberg, Norman R. Braton, Welding and Other Joining Processes, 1976, Allyn and Byron Inc., Boston, TS 227 L58, Concordia University Librairy.
4.J. Hamer, Engineering Applications of Adhesives, 1988, Butterworths, London,UK, TP 968 E53, Concordia University Librairy.
5.E. Lawley, Engineering Applications of Adhesives, 1988, Butterworths, London,UK, TP 968 E53, Concordia University Librairy.
6.E. Paul De Garno, J.T. Black, Ronald A. Koltser, Materials and Processes in Manufacturing, 4th edition, 1997, Prentice-Hall Inc., Upper Saddle River NJ.
7.W.A. Lees, Adhesives in Engineering Design, 1984, Springer-Verlag, London,
TA 455 A 34L 44, Concordia University Librairy.
8.D.M. Brewis, D. Briggs, Industrial Adhesion Problems, 1985, Orbital Press, Oxford,
TP 968 I52, Concordia University Librairy.
9.Charles V. Cagle, Adhesive Bonding Techniques and Applications, 1968, McGraw-
Hill Book Company, South El Monte, California, TP 968 C3, Concordia University Librairy.
10. http://www.loctite.com/literature/design_metal.html” The Loctite Design Guide for Bonding Metals, Loctite Corporation, 2001.