Individuals and Their Discoveries Are Not Enough to Bring Medical Progress Essay Example for Free

Individuals and Their Discoveries Are Not Enough to Bring Medical Progress Essay Individuals and their discoveries are not enough on their own to bring medical progress. Explain how far this statement applies to Jenner and his work. Jenner’s discovery of the link between cowpox and smallpox was significant to the development of a vaccine for smallpox. However, it can be argued that Jenner and his discovery were not enough on their own to bring medical progress. The factors Scientific thinking, Government Communication and Changing attitudes played a major and important role to bring medical progress. One reason as to why the statement applies to Jenner and his work is because the Government worked in Jenners favour to bring medical progress. In 1802 and 1807, Parliament gave Edward Jenner  £30,000 to develop his work on vaccination. This clearly indicates that without the help of Parliament, Jenner’s work would not have shown as much signs of advancement; hence he would not have had the money to progress. In addition to this, fifty years later vaccination was made compulsory in Britain which led a dramatic drop in smallpox cases. This evidently shows that without the help of the Government, Jenner’s work would not have been as widely spread and used by the people as much; therefore the government did play a significant role his Edward Jenner’s development of Vaccinations. A different explanation as to why the statement is relevant to Jenner and his work is because of the communication. This factor is seen to have an impact on the medical progress of Jenner, is because without the spread of Jenner’s discoveries, people would not be aware of vaccinations. In 1798, Jenner published his own accounts of his discover, spreading the details of his methods worldwide. Consequently, that people could see his work but scientists in particular were able to see his work and they could learn from his work. This is evidence that by spreading his work worldwide, it brought medical progress; it was not just Edward Jenner alone brought medical progress to the development of a vaccine for smallpox. A different factor as to why the statement applies to Jenner and his work is because of the changing attitudes. Due to many people who had begun to think in a more scientific way, this meant that they were more open into accepting Jenner’s theory for Vaccinations. This implies that if people’s attitudes were similar to people who had supernatural beliefs, they would not have accepted the theory, therefore without the changing attitudes, Jenner’s work would not have caused a huge medical progression. Another reason which explains how the statement is relevant to Jenner and his work is because of the scientific thinking. Edward Jenner was able to use scientific method and experimentation in his research which is a clear indication his work can be considered trustworthy and it is likely to be accurate. Jenner also tested out his theory on a small boy which proved his theory to be correct but also on twenty-three other people. This shows that without the scientific methods and experiments, Jenner would not have reached the conclusion that his hypothesis was correct; therefore this is evidence for medical progress. Jenner’s scientific thinking is a key factor because without it, scientists would not have been able to see his work. Also his work would not have been as widely spread; people would not trust his work if it hadn’t been tested accurately, therefore people would not use his work. Another explanation as to why the statement applies to Jenner and his work is because of the individuals. Jenner himself had the insight to realise the link between cowpox and smallpox was important. If Jenner was not a determined individual and did not carry and publish his research, the theory of vaccination would most likely not exist today. Jenner had carried on, despite opposition and criticism which indicates with Jenner’s determination, he brought medical progress. In addition to this, Jenner also tested his theory of vaccination on twenty three people, including his six month old baby which shows he is a very dedicated individual. To conclude, there are many factors to support this statement: Government, Communication, Changing attitudes and Scientific thinking all bring medical progress, alongside the individuals and their discoveries. However, Scientific thinking caused the biggest impact on the medical progress because without whilst his methods and experiments, people would not trust his work, therefore people would not use his work.

United States Declaration of Independence and British Soldiers Essay Example for Free

United States Declaration of Independence and British Soldiers Essay 1. Examine the factors that led to the colonies’ declaration of independence from England. Make sure to explain WHY the colonies decided to break from their mother-country as well as any risks that doing so might have entailed. Also include your interpretation of whether or not breaking away from England was a good idea for the colonies. After the French and Indian War, Great Britain gained lots of territories but lost lots of money. Great Britain did not want to quickly occupy this territory so they decided to make the Quartering acts. The first quartering acts basically said that British Soldiers can board free at inns and stay at abandon houses. In order to make up for the loss of money. Great Britain put lots of taxes on imports and exports as well as other laws that limited Port Cities like Boston from making money off their ports. Taxation without representation was the main factor which led the American colonies to declare their independence from Great Britain. The Sugar Act was the first in the series of British Colonial taxation acts that provided fuel for revolutionary mood in American colonies. Shortly thereafter came the British Stamp Act. This time the new tax burden took form of official stamps that colonists had to purchase and that were required for legal contracts, newspapers, and other official paperwork. The protests in the colonies started as the news broke. This led to the creation of The Sons of Liberty. Under John Adams they organized riots and violent attacks to intimidate tax collectors. The Sons of Liberty decided to harass a couple of British Soldiers Stationed at Boston. The Soldiers had no choice but to fire on the crowd killing a few people, this was called the Boston massacre. Later a British Official decided to confront John Hancock for smuggling tea. Later the sons of liberty destroyed an entire shipment of British tea. This Caused Great Britain to bring in even harsher laws. These included the following, British soldiers and officials are to be tried in a British Court and not in the colonies. British Soldiers are to quarter any houses they want and board in them without the permission of the owner. The Colonies were prohibited from having their own town council meetings. This caused the Colonist to form the Continental Congress. John Adams, who represented Massachusetts, tried to convince the rest of the colonist to fight but he had trouble convincing other colonies, mostly Pennsylvania. A few meetings later with the help of Benjamin Franklin and John Adams, Thomas Jefferson Wrote the Declaration of Independence. After years of fighting the Parliament and the King finally recognized the colonies as their own separate country. Although, breaking from their mother-country would make The British Empire, the largest in the world at the time, become their enemies, the Colonies would be free of obeying any laws set out by the British, could create their own democracy and get France as an ally.

Active or Passive Third Stage of Labour: Pros and Cons

Active or Passive Third Stage of Labour: Pros and Cons Introduction This dissertation is primarily concerned with the arguments that are currently active in relation to the benefits and disadvantages of having either an active or passive third stage of labour. We shall examine this issue from several angles including the currently accepted medical opinions as expressed in the peer reviewed press, the perspective of various opinions expressed by women in labour and theevidence base to support these opinions. It is a generally accepted truism that if there is controversy surrounding a subject, then this implies that there is not a sufficiently strong evidence base to settle the argument one way or the other. (De Martino B et al. 2006). In the case of this particular subject, this is possibly not true, as the evidence base is quite robust (and we shall examine this in due course). Midwifery deals with situations that are steeped in layers of strongly felt emotion, and this has a great tendency to colour rational argument. Blind belief in one area often appears to stem from total disbelief in another (Baines D. 2001) and in consideration of some of the literature in this area this would certainly appear to be true. Let us try to examine the basic facts of the arguments together with the evidence base that supports them. In the civilised world it is estimated that approximately 515,000 currently die annually from problems directly related to pregnancy. (extrapolated from Hill K et al. 2001). The largest single category of such deaths occur within 4 hrs. of delivery, most commonly from post partum haemorrhage and its complications (AbouZahr C 1998), the most common factor in such cases being uterine atony. (Ripley D L 1999). Depending on the area of the world (as this tends to determine the standard of care and resources available), post partum haemorrhage deaths constitutes between 10-60% of all maternal deaths (AbouZahr C 1998). Statistically, the majority of such maternal deaths occur in the developing countries where women may receive inappropriate, unskilled or inadequate care during labour or the post partum period. (PATH 2001). In developed countries the vast majority of these deaths could be (and largely are) avoided with effective obstetric intervention. (WHO 1994). One of the central argumen ts that we shall deploy in favour of the active management of the third stage of labour is the fact that relying on the identification of risk factors for women at risk of haemorrhage does not appear to decrease the overall figures for post partum haemorrhage morbidity or mortality as more than 70% of such cases of post partum haemorrhage occur in women with no identifiable risk factors. (Atkins S 1994). Prendiville, in his recently published Cochrane review (Prendiville W J et al. 2000) states that: where maternal mortality from haemorrhage is high, evidence-based practices that reduce haemorrhage incidence, such as active management of the third stage of labour, should always be followed It is hard to rationally counter such an argument, particularly in view of the strength of the evidence base presented in the review, although we shall finish this dissertation with a discussion of a paper by Stevenson which attempts to provide a rational counter argument in this area. It could be argued that the management of the third stage of labour, as far as formal teaching and published literature is concerned, is eclipsed by the other two stages (Baskett T F 1999). Cunningham agrees with this viewpoint with the observation that a current standard textbook of obstetrics (unnamed) devotes only 4 of its 1,500 pages to the third stage of labour but a huge amount more to the complications that can arise directly after the delivery of the baby (Cunningham, 2001). Donald makes the comment This indeed is the unforgiving stage of labour, and in it there lurks more unheralded treachery than in both the other stages combined. The normal case can, within a minute, become abnormal and successful delivery can turn swiftly to disaster. (Donald, 1979). chapter 1:define third stage of labour, The definition of the third stage of labour varies between authorities in terms of wording, but in functional terms there is general agreement that it is the part of labour that starts directly after the birth of the baby and concludes with the successful delivery of the placenta and the foetal membranes. Functionally, it is during the third stage of labour that the myometrium contracts dramatically and causes the placenta to separate from the uterine wall and then subsequently expelled from the uterine cavity. This stage can be managed actively or observed passively. Practically, it is the speed with which this stage is accomplished which effectively dictates the volume of blood that is eventually lost. It follows that if anything interferes with this process then the risk of increased blood loss gets greater. If the uterus becomes atonic, the placenta does not separate efficiently and the blood vessels that had formally supplied it are not actively constricted. (Chamberlain G et al. 1999). We shall discuss this process in greater detail shortly. Proponents of passive management of the third stage of labour rely on the normal physiological processes to shut down the bleeding from the placental site and to expel the placenta. Those who favour active management use three elements of management. One is the use of an ecbolic drug given in the minute after delivery of the baby and before the placenta is delivered. The second element is early clamping and cutting of the cord and the third is the use of controlled cord traction to facilitate the delivery of the placenta. We shall discuss each of these elements in greater detail in due course. The rationale behind active management of the third stage of labour is basically that by speeding up the natural delivery of the placenta, one can allow the uterus to contract more efficiently thereby reducing the total blood loss and minimising the risk of post partum haemorrhage. (ODriscoll K 1994) discuss optimal practice, Let us start our consideration of optimal practice with a critical analysis of the paper by Cherine (Cherine M et al. 2004) which takes a collective overview of the literature on the subject. The authors point to the fact that there have been a number of large scale randomised controlled studies which have compared the outcomes of labours which have been either actively or passively managed. One of the biggest difficulties that they experienced was the inconsistency of terminology on the subject, as a number of healthcare professionals had reported management as passive when there had been elements of active management such as controlled cord traction and early cord clamping. As an overview, they were able to conclude that actively managed women had a lower prevalence of post partum haemorrhage, a shorter third stage of labour, reduced post partum anaemia, less need for blood transfusion or therapeutic oxytocics (Prendiville W J et al. 2001). Other factors derived from the paper include the observation that the administration of oxytocin before delivery of the placenta (rather than afterwards), was shown to decrease the overall incidence of post partum haemorrhage, the overall amount of blood loss, the need for additional uterotonic drugs, the need for blood transfusions when compared to deliveries with similar duration of the third stage of labour as a control. In addition to all of this they noted that there was no increased incidence of the condition of retained placenta. (Elbourne D R et al. 2001). The evidence base for these comments is both robust and strong. On the face of it, there seems therefore little to recommend the adoption of passive manage ment of the third stage of labour. Earlier we noted the difficulties in definition of active management of the third stage of labour. In consideration of any individual paper where interpretation of the figures are required, great care must therefore be taken in assessing exactly what is being measured and compared. Cherine points to the fact that some respondents categorised their management as passive management of the third stage of labour when, in reality they had used some aspect of active management. They may not have used ecbolic drugs (this was found to be the case in 19% of the deliveries considered). This point is worth considering further as oxytocin was given to 98% of the 148 women in the trial who received ecbolic. In terms of optimum management 34% received the ecbolic at the appropriate time (as specified in the management protocols as being before the delivery of the placenta and within one minute of the delivery of the baby). For the remaining 66%, it was given incorrectly, either after the delivery of the placenta or, in one case, later than one minute after the delivery of the baby. Further analysis of the practices reported that where uterotonic drugs were given, cord traction was not done in 49%, and early cord clamping not done in 7% of the deliveries observed where the optimum active management of the third stage of labour protocols were not followed. >From an analytical point of view, we should cite the evidence base to suggest the degree to which these two practices are associated with morbidity. Walter P et al. 1999 state that their analysis of their data shows that early cord clamping and controlled cord traction are shown to be associated with a shorter third stage and lower mean blood loss, whereas Mitchelle (G G et al. 2005) found them to be associated with a lower incidence of retained placenta. Other considerations relating to the practice of early cord clamping are that it reduces the degree of mother to baby blood transfusion. It is clear that giving uterotonic drugs without early clamping will cause the myometrium to contract and physically squeeze the placenta, thereby accelerating the both the speed and the total quantity of the transfusion. This has the effect of upsetting the physiological balance of the blood volume between baby and placenta, and can cause a number of undesirable effects in the baby including an increased tendency to jaundice. (Rogers J et al. 1998) The major features that are commonly accepted as being characteristic of active management and passive management of the third stage of labour are set out below. Physiological Versus Active Management . . Physiological Management Active Management Uterotonic None or after placenta delivered With delivery of anterior shoulder or baby Uterus Assessment of size and tone Assessment of size and tone Cord traction None Application of controlled cord traction* when uterus contracted Cord clamping Variable Early (After Smith J R et al. 1999) physiology of third stage The physiology of the third stage can only be realistically considered in relation to some of the elements which occur in the preceding months of pregnancy. The first significant consideration are the changes in haemodynamics as the pregnancy progresses. The maternal blood volume increases by a factor of about 50% (from about 4 litres to about 6litres). (Abouzahr C 1998) This is due to a disproportionate increase in the plasma volume over the RBC volume which is seen clinically with a physiological fall in both Hb and Heamatocrit values. Supplemental iron can reduce this fall particularly if the woman concerned has poor iron reserves or was anaemic before the pregnancy began. The evolutionary physiology behind this change revolves around the fact that the placenta (or more accurately the utero-placental unit) has low resistance perfusion demands which are better served by a high circulating blood volume and it also provides a buffer for the inevitable blood loss that occurs at the time of delivery. (Dansereau J et al. 1999). The high progesterone levels encountered in pregnancy are also relevant insofar as they tend to reduce the general vascular tone thereby increase venous pooling. This, in turn, reduces the venous return to the heart and this would (if not compensated for by the increased blood volume) lead to hypotension which would contribute to reductions in levels of foetal oxygenation. (Baskett T F 1999). Coincident and concurrent with these heamodynamic changes are a number of physiological changes in the coagulation system. There is seen to be a sharp increase in the quantity of most of the clotting factors in the blood and a functional decrease in the fibrinolytic activity. (Carroli G et al. 2002). Platelet levels are observed to fall. This is thought to be due to a combination of factors. Haemodilution is one and a low level increase in platelet utilisation is also thought to be relevant. The overall functioning of the platelet system is rarely affected. All of these changes are mediated by the dramatic increase in the levels of circulating oestrogen. The relevance of these considerations is clear when we consider that one of the main hazards facing the mother during the third stage of labour is that of haemorrhage. (Soltani H et al. 2005) and the changes in the haemodynamics are largely germinal to this fact. The other major factor in our considerations is the efficiency of the haemostasis produced by the uterine contraction in the third stage of labour. The prime agent in the immediate control of blood loss after separation of the placenta, is uterine contraction which can exert a physical pressure on the arterioles to reduce immediate blood loss. Clot formation and the resultant fibrin deposition, although they occur rapidly, only become functional after the coagulation cascade has triggered off and progressed. Once operative however, this secondary mechanism becomes dominant in securing haemostasis in the days following delivery. (Sleep, 1993). The uterus both grows and enlarges as pregnancy progresses under the primary influence of oestrogen. The organ itself changes from a non-gravid weight of about 70g and cavity volume of about 10 ml. to a fully gravid weight of about 1.1 kg. and a cavity capacity of about 5 litres. This growth, together with the subsequent growth of the feto-placental unit is fed by the increased blood volume and blood flow through the uterus which, at term, is estimated to be about 5-800 ml/min or approximately 10-15% of the total cardiac output (Thilaganathan B et al. 1993). It can therefore be appreciated why haemorrhage is a significant potential danger in the third stage of labour with potentially 15% of the cardiac output being directed towards a raw placental bed. The physiology of the third stage of labour also involves the mechanism of placental expulsion. After the baby has been delivered, the uterus continues to contract rhythmically and this reduction in size causes a shear line to form at the utero-placental junction. This is thought to be mainly a physical phenomenon as the uterus is capable of contraction, whereas the placenta (being devoid of muscular tissue) is not. We should note the characteristic of the myometrium which is unique in the animal kingdom, and this is the ability of the myometrial fibres to maintain its shortened length after each contraction and then to be able to contract further with subsequent contractions. This characteristic results in a progressive and (normally) fairy rapid reduction in the overall surface area of the placental site. (Sanborn B M et al. 1998) In the words of Rogers (J et al. 1998), by this mechanism the placenta is undermined, detached, and propelled into the lower uterine segment. Other physiological mechanisms also come into play in this stage of labour. Placental separation also occurs by virtue of the physical separation engendered by the formation of a sub-placental haematoma. This is brought about by the dual mechanisms of venous occlusion and vascular rupture of the arterioles and capillaries in the placental bed and is secondary to the uterine contractions (Sharma J B et al. 2005). The physiology of the normal control of this phenomenon is both unique and complex. The structure of the uterine side of the placental bed is a latticework of arterioles that spiral around and inbetween the meshwork of interlacing and interlocking myometrial fibrils. As the myometrial fibres progressively shorten, they effectively actively constrict the arterioles by kinking them . Baskett (T F 1999) refers to this action and structure as the living ligatures and physiologic sutures of the uterus. These dramatic effects are triggered and mediated by a number of mechanisms. The actual definitive trigger for labour is still a matter of active debate, but we can observe that the myometrium becomes significantly more sensitive to oxytocin towards the end of the pregnancy and the amounts of oxytocin produced by the posterior pituitary glad increase dramatically just before the onset of labour. (GÃ ¼lmezoglu A M et al. 2001) It is known that the F-series, and some other) prostaglandins are equally active and may have a role to play in the genesis of labour. (Gulmezoglu A M et al. 2004) >From an interventional point of view, we note that a number of synthetic ergot alkaloids are also capable of causing sustained uterine contractions. (Elbourne D R et al. 2002) chapter 2 discuss active management, criteria, implications for mother and fetus. This dissertation is asking us to consider the essential differences between active management and passive management of the third stage of labour. In this segment we shall discuss the principles of active management and contrast them with the principles of passive management. Those clinicians who practice the passive management of the third stage of labour put forward arguments that mothers have been giving birth without the assistance of the trained healthcare professionals for millennia and, to a degree, the human body is the product of evolutionary forces which have focussed upon the perpetuation of the species as their prime driving force. Whilst accepting that both of these concepts are manifestly true, such arguments do not take account of the natural wastage that drives such evolutionary adaptations. In human terms such natural wastage is simply not ethically or morally acceptable in modern society. (Sugarman J et al. 2001) There may be some validity in the arguments that natural processes will achieve normal separation and delivery of the placenta and may lead to fewer complications and if the patient should suffer from post partum haemorrhage then there are techniques, medications and equipment that can be utilised to contain and control the clinical situation. Additional arguments are invoked that controlled cord traction can increase the risk of uterine inversion and ecbolic drugs can increase the risks of other complications such as retained placenta and difficulties in delivering an undiagnosed twin. (El-Refaey H et al. 2003) The proponents of active management counter these arguments by suggesting that the use of ecbolic agents reduces the risks of post partum haemorrhage, faster separation of the placenta, reduction of maternal blood loss. Inversion of the uterus can be avoided by using only gentle controlled cord traction when the uterus is well contracted together with the controlling of the uterus by the Brandt-Andrews manoeuvre. The arguments relating to the undiagnosed second twin are loosing ground as this eventuality is becoming progressively more rare. The advent of ultrasound together with the advent of protocols which call for the mandatory examination of the uterus after the birth and before the administration of the ecbolic agent effectively minimise this possibility. (Prendiville, 2002). If we consider the works of Prendiville (referred to above) we note the meta-analyses done of the various trials on the comparison of active management against the passive management of the third stage of labour and find that active management consistently leads to several benefits when compared to passive management. The most significant of which are set out below. Benefits of Active Management Versus Physiological Management Outcome Control Rate, % Relative Risk 95% CI* NNT 95% CI PPH >500 mL 14 0.38 0.32-0.46 12 10-14 PPH >1000 mL 2.6 0.33 0.21-0.51 55 42-91 Hemoglobin 6.1 0.4 0.29-0.55 27 20-40 Blood transfusion 2.3 0.44 0.22-0.53 67 48-111 Therapeutic uterotonics 17 0.2 0.17-0.25 7 6-8 *95% confidence interval Number needed to treat (After Prendiville, 2002). The statistics obtained make interesting consideration. In these figures we can deduce that for every 12 patients receiving active management (rather than passive management) one post partum haemorrhage is avoided and further extrapolation suggests that for every 67 patients managed actively one blood transfusion is avoided. With regard to the assertions relating to problems with a retained placenta, there was no evidence to support it, indeed the figures showed that there was no increase in the incidence of retained placenta. Equally it was noted that the third stage of labour was significantly shorter in the actively managed group. In terms of significance for the mother there were negative findings in relation to active management and these included a higher incidence of raised blood pressure post delivery (the criteria used being > 100 mm Hg). Higher incidences of reported nausea and vomiting were also found although these were apparently related to the use of ergot ecbolic

Ben Carson with Cecil MurpheyGifted Hands The Ben Carson Story :: Essays Papers

Ben Carson with Cecil MurpheyGifted Hands The Ben Carson Story The book is about a kid who grew up in a harsh area, in other words a â€Å"ghetto†. The books starts out when Ben is in fifth grade when he is failing all his classes because he couldn’t see anything without glasses that his family couldn’t afford. But after Ben got glasses he became the smartest student in all his classes. He was a very smart and good student until he reached the beginning of high school. When he entered the ninth grade year he began to be embarrassed of his social standing because people would â€Å"cap† on him and also because he wore old clothes. He was in this period until the middle of the 10th grade when his mom and the ROTC straightened him out. After that he graduated high school and attended college at Yale. While at Yale he had money problems and barely had enough money to survive. He graduated and married his wife Cookie and became a neurosurgeon. He his known as one of the top neurosurgeons if not the top neu rosurgeon because he took difficult cases which all other neurosurgeons wouldn’t take the risk to do. The message of this book is basically never give up and always try to do your best no matter what the situation and you should remember that God is with one and he should be the priority in ones life. Well for different people the message of this book could be considered important or unimportant. The ideas of this book are of importance to certain people and these certain people should consider it. There are expressions of the author shown through certain incidents like when mid-terms came during a year at Yale he was unprepared because of his procrastinating studying techniques but the night before the exam while reviewing his notes he prayed for god to help him do good on the test and he had a dream about the test and the answers were in front of him, this expressed his philosophy of god helping one if they ask. The author never tried to convince me of a point of view but he gave different examples of situations and how he settled those situations. After reading this book I found some similarities of my daily life.

Essays --

Around the turn of the last century, and in the nineteen hundreds, much literature was sent from Canada to the United States for the benefit of those that were interested in farming. People were led to believe that a short cut to happiness and prosperity was to simply go to Canada. It all sounded so interesting. It was written that anyone coming to Canada received 160 acres of land for ten dollars plus slight homestead duties. Canada was the land where you never heard the thunder. It usually rained only at night and the water was so pure, one could drink water off the ground anywhere and it would not make you sick. When you wanted fresh meat, all you had to do was open the door and shoot your choice of the wild game that was so abundant. Seeing no future for themselves as young farmers, on poor, stoney and heavily timbered land at Fosston, Minnesota, several families left for Canada to look for these homesteads. After arriving in Wadena, and with the local guide, the men began walki ng in the north direction. They followed an old Indian trail over to the quarter sections of land available for proving as homesteads. Each man selected a quarter that he would work, they were all enjoined. They had now put in two days of interesting and educationaldiscoveruies. Interesting, in that it looked like there was a future for this country and educational, in learning that you could not expect to be able to do much walking if you drank the supposedly pure water lying everywhere on top of the ground. The local guide was already a seasoned homesteader and anyone that knew him would realize that he knew how sick, those poor greenhorns would get from drinking all that slough water. The next day, they walked back to Wadena and took the train to Hu... ... We had so many ducks that winter that we couldn't eat them all before the weather turned warm in the spring. When we tired of eating duck, there were lots of bush rabbits, and when we tired of rabbits, we ate duck. On the 20th of march 1949, I awoke one morning to find mom in an unusual mood and she told me dad had left for a drive with Cathy and the buggy during the night. For the life of me, I could not grasp what was going on, or what was to take place. Then I heard the buggy on the frozen ground and sure enough, dad was home. He had a passenger with him. She was an older lady and I was told her name was Mrs. Thorsen. I was then told to hook up Black, a calf we had broken, and to drive to the new neighbors to see how the building of their new house was coming along. I went, but I was not away very long because I knew the circumstances were not ordinary at home.

FM Receivers Essay -- essays research papers

Abstract This paper will discuss the design of an FM receiver. It will begin with a brief historical backdrop of FM broadcasting and its use in society. It will continue by providing the necessary mathematical background of the modulation process. Furthermore, it will enumerate some of the advantages of FM over other forms of modulation, namely AM. Finally, the paper will discuss the design of a basic FM receiver as well as introduce some circuits and circuit components which the reader may not be familiar with. Introduction Frequency modulation (FM) was invented in 1936 by an American electrical engineer/ inventor named Edwin H. Armstrong. Possessing numerous advantages over the existing AM broadcasting system, as will be discussed later, in combination with relatively low cost of implementation, resulted in its rapid growth. In the years following World War Two, there were 600 licensed stations broadcasting in the U.S. By 1980, the number grew to 4000. On another historical note, in 1961 stations began broadcasting in stereo. The basic receiver design consists of the following components. An antenna is used to convert electro-magnetic waves into electrical oscillations. Amplifiers are used throughout the receiver to boost signal power at radio, baseband and intermediate frequencies. The core of the FM receiver, the discriminator, comes in various circuit forms and is used in detection and demodulation. Basically, its role is to extract the intelligence or message from the carrier wave. Another component, essential in most electronic circuits, is the power supply (DC or AC converted to DC). Finally, a transducer (speaker in the case of Radio) is needed to convert the message signal into its final form (audio, mechanical, etc ¡Ã‚ ­). Other components more specific to FM receivers are mixers combined with local oscillators used for frequency manipulation, limiters to control amplitude, de-emphasis and other filter circuits. 2 Mathematics of FM Unlike amplitude modulation (AM) where the message or modulating signal, call it m(t), is used to modulate the amplitude of the carrier signal, frequency modulation, as the name implies, uses m(t) to transform the frequency of the carrier. The amplitude of an FM signal should remain constant during the modulating process; an important property of FM. A general FM signal can be described by the following:1  ¦Ã‚ µFM(t) = Acos( ¦ÃƒË†... ...n its output proportional to s(t). Over a short time interval, this variation  ¡Ãƒâ€" C(wc-wo)t. Thus, the system continues to loop until the frequency of the VCO output matches or  ¡Ã‚ °locks ¡Ã‚ ± onto the incoming frequency. The time it takes for the system to  ¡Ã‚ °lock ¡Ã‚ ± is called the acquisition time. Once the frequencies match, s(t) becomes s(t) = AB/s sin( ¦ÃƒË†c- ¦ÃƒË†o) For an incoming FM signal s(t) = AB/2 sin( ¦ÃƒË†c(t)- ¦ÃƒË†o) = AB/2 sin (kf  ¡Ãƒâ€™m( ¦Ãƒâ€œ)d ¦Ãƒâ€œ  ¨C ¦ÃƒË†o) Running s(t) through a differentiator results in an AM signal which can be easily demodulated using envelope detection. Once the signal has been demodulated, it is then passed through a de-emphasis circuit, as mentioned earlier. Typically, it is then amplified one last time before heading to the output transducer. Conclusion In conclusion, the modulation/demodulation process for FM signals has proven to be much less straight forward than simple AM modulation. However, FM has considerable advantages and its use in radio, satellite and radar applications make it indispensable. Many methods of signal and system analysis along with filter and feedback design are employed in the building of an FM receiver, whether it be analog, digital or otherwise. FM Receivers Essay -- essays research papers Abstract This paper will discuss the design of an FM receiver. It will begin with a brief historical backdrop of FM broadcasting and its use in society. It will continue by providing the necessary mathematical background of the modulation process. Furthermore, it will enumerate some of the advantages of FM over other forms of modulation, namely AM. Finally, the paper will discuss the design of a basic FM receiver as well as introduce some circuits and circuit components which the reader may not be familiar with. Introduction Frequency modulation (FM) was invented in 1936 by an American electrical engineer/ inventor named Edwin H. Armstrong. Possessing numerous advantages over the existing AM broadcasting system, as will be discussed later, in combination with relatively low cost of implementation, resulted in its rapid growth. In the years following World War Two, there were 600 licensed stations broadcasting in the U.S. By 1980, the number grew to 4000. On another historical note, in 1961 stations began broadcasting in stereo. The basic receiver design consists of the following components. An antenna is used to convert electro-magnetic waves into electrical oscillations. Amplifiers are used throughout the receiver to boost signal power at radio, baseband and intermediate frequencies. The core of the FM receiver, the discriminator, comes in various circuit forms and is used in detection and demodulation. Basically, its role is to extract the intelligence or message from the carrier wave. Another component, essential in most electronic circuits, is the power supply (DC or AC converted to DC). Finally, a transducer (speaker in the case of Radio) is needed to convert the message signal into its final form (audio, mechanical, etc ¡Ã‚ ­). Other components more specific to FM receivers are mixers combined with local oscillators used for frequency manipulation, limiters to control amplitude, de-emphasis and other filter circuits. 2 Mathematics of FM Unlike amplitude modulation (AM) where the message or modulating signal, call it m(t), is used to modulate the amplitude of the carrier signal, frequency modulation, as the name implies, uses m(t) to transform the frequency of the carrier. The amplitude of an FM signal should remain constant during the modulating process; an important property of FM. A general FM signal can be described by the following:1  ¦Ã‚ µFM(t) = Acos( ¦ÃƒË†... ...n its output proportional to s(t). Over a short time interval, this variation  ¡Ãƒâ€" C(wc-wo)t. Thus, the system continues to loop until the frequency of the VCO output matches or  ¡Ã‚ °locks ¡Ã‚ ± onto the incoming frequency. The time it takes for the system to  ¡Ã‚ °lock ¡Ã‚ ± is called the acquisition time. Once the frequencies match, s(t) becomes s(t) = AB/s sin( ¦ÃƒË†c- ¦ÃƒË†o) For an incoming FM signal s(t) = AB/2 sin( ¦ÃƒË†c(t)- ¦ÃƒË†o) = AB/2 sin (kf  ¡Ãƒâ€™m( ¦Ãƒâ€œ)d ¦Ãƒâ€œ  ¨C ¦ÃƒË†o) Running s(t) through a differentiator results in an AM signal which can be easily demodulated using envelope detection. Once the signal has been demodulated, it is then passed through a de-emphasis circuit, as mentioned earlier. Typically, it is then amplified one last time before heading to the output transducer. Conclusion In conclusion, the modulation/demodulation process for FM signals has proven to be much less straight forward than simple AM modulation. However, FM has considerable advantages and its use in radio, satellite and radar applications make it indispensable. Many methods of signal and system analysis along with filter and feedback design are employed in the building of an FM receiver, whether it be analog, digital or otherwise.

Development and Design

It has been discussed at large that to sustain the revenue growth and the value; organizations need to be innovative at different strata and phases of market and product life cycle respectively. Considering the issue of Virgin Mobile, it is a matter of problem solving propelled by the uncertainty of the stakeholders support and the forecasted possibilities of failing of the existing service plans. Though; to nullify the risk factor of diminishing revenue and the brand image, substitute product coupled with service plane has been introduced.But, like most of the products it will take the brand through a wild ride to gain the market acceptance and to justify its stand against its competitors. To deal the issue strategically; the paper will assess and evaluate the product development process, while differentiating the case of new and existing products, factors of product designing, system administration for new product beta stage, re-launching of product into new market and factors invo lved in designing the proposed product. The holistic approach under the spotlight in this paper is about the process of the product development.New product development (NPD) is the concept of total cycle of the product engineering; to market the new product or the service to boost the business. The process can be executed by following a parallel dual path transition. One path looks after the idea generation, product design, and the detailing of the product engineering. But interestingly, the progression and the acceptance of the proposal of a new product can only take place; if the other side of the parallel process takes its stand.The other way that involves the activities like market research and marketing analysis carry ground work to formulate the further plans that propels the details engineering. The product life cycle management, which observes and help sustain the growth of the market share through the quadrants of the life cycle curve, considers the development of the new p roduct to be the first stage of promoting and marketing the new product in the entire product life cycle.In this inception stage, the development process has structured steps of thinking about the product, its viability to the target audience, its needs and the features required, the sales projection and the revenue expected to be generated, having a real time experience with the product proposed and the other ancillary plans to make the product market. The above stated gist can be technically explained under the following sub-headings. Idea Generation: The brainstorming activity for the new product can only take place when the organization has already conducted the SWOT and the opportunity analysis.A clear conception out these tests helps ideate to take the project forward. This also takes the process to its next level of idea screening. Idea Screening: As the meaning of screening suggests; it eliminates the possible unwanted elements in the course of the new product development. I t seeks about the product benefit to the customers. The size and the projected growth factors in the new market and the market trend of the product or service concept is based on. This to measure how feasible will it be to manufacture the same; technically in regard of cost to price ratio.Concept Development and Testing: In short, this involves the product engineering, which further involves the issues like, end users, the features, product benefit, and cost effectiveness of the product, experiencing a real time scenario and deciding on the actual market price. To gather knowledge on these; it takes a thorough survey of the target segment. Business Analysis: Depending on the potential customer feedback and the competitors stand, the process again revises the ideal selling price of the proposed product to be marketed.Other measures that follow the suite are the sales volume projection calculated on market size, estimated bottom-line and the break-even point. Beta Stage: This is a dra matic event of conducting the real time execution of the proposed product. This is the prototype stage where the product is being used on the customer to collect feedbacks and acceptance by introducing at the shows and conducting interviews. This helps to build the brand identification process that will boost the initial selling in the actual scenario.Technical Implementations and Commercialization mostly considered as the post-NPD activity consider the ancillary factors like the resource estimation, operational planning and the vendor line-up and the other logistic issues. Besides, it steers the post NPD promotional agendas and the channel management too (Ulrich and Eppinger, 2004). To manufacture a new product that suites the market, it needs an important consideration of the factors that make the product designing a success in the market.In the gamut of product management; credit for the successful new product designing that took the market decently, goes to the category of indus trial designing. This genre has an unparallel contribution to product designing in terms of technical know-how, product, its process, aesthetics, usability, and ergonomics. It has the keen observation on product engineering, attributes, market placement; leading to attractiveness, psychology, customers’ need, want and desire and the emotional attachment of the end users with the brand.According to different designers and school of thought the designing aspects may vary though (Pulos, 1988). The factors of new product designing are the professional concepts to create and develop inputs that strike the balance and logisize the function, value and the look of the products and services to leverage a common benefit for both the user and the manufacturer. The concept is big enough to encompass the entire development process of a new product. But in the year 1967, the total concept has focused of the five major backgrounds as per Dreyfuss.Utility: This counts on the products’ user interface in terms of safety, ergonomic approach, and the perceived value of the consumers. Here the concern about the features is about communicating there utilities to the customers. Likewise Virgin’s Data card alone; gives an internet support on go. It is mobile and can enhance the communicating usage of laptops or notebooks. Further, the alternative plan of strategic partnership with IT companies will facilitate the communication features of the notebooks; following a diversified revenue earning.Appearance: This factor reflects the plan and the success of stand-alone proposed product in the crowd of the competitors to stand out of the crowd. As the market is flooded with me too products, the factor like this takes care of form, shape, size, proportion, and color to provide the customers a pleasing presentation. This is particularly in terms of the data card only, not the product development and enhancement with strategic partnership. Ease of maintenance: In this jet age, clients will hardly have the spare to dedicate and cherish the product.The main concern would be the performance and service of the product, for which the factor stated shoulders the responsibilities of easy maintenance, which will not need high involvement of the owner and accessibility to the service hubs for effective after-sales-service. Low costs: To equip the product with forms and features the market price of the same finally goes up. For Virgin; it should bear in mind that proposed product is going to make-up the revenue gap and is set to gain back the confidence of the stake holders.Thus keeping the cost low will help the product and organization to penetrate the new market and introduce the newly developed product smoothly. Communication: This is the factor that highlights the visual features of the product and of course the organizational and brand image. Communication reflects the philosophy of the company; with which the stake holders are heavily involved. In case the product is communicated well from all the aspects; it will help to go off the rack fast, with a promise of yielding more revenue from the process.The entire process plays a significant role surrounding the forte of industrial designing and goes hand-in-hand to lay down the factors of product designing for a successful commercialization (Ulrich and Eppinger, 2004). After the session long development process of a new product the most challenging stage comes with the appearance of moment of truth. At this stage; the organization put proposed product in a usable model to collect the customers’ reactions to predict potential future of the product in the real market situation.Though mostly people consider prototype to be a fully functional model with full form and shape, to be examined by the potential customers, it is further subdivided by the designers as the comprehensive prototype and the focused prototype. The initial type is the essential form the model determining the s uccess and the coordination of all the components, and judging how well they are functioning together. Where as the latter; being focused deals with the limited number of attributes and features.The model; here is more ken in observing certain areas of concern. This can be of importance while developing an existing product design, where the designer knows the particular area needs to be modified or revamped. But; to ensure the smooth running of the concept, a system administration is required to steer the phase. This counts the administrative faculties like, Quality of the user interface that will evaluate whether the data card is understandable by the user and is easy to handle or jack-in into the ports of notebooks.Will the Emotional appeal meet the psychological needs of the customers to make the product a success? Maintenance and repairing process should be easy and user friendly to the users. Appropriate use of resources oversees the right usage of features that will fetch the customer his or her value for money, etc (Crawford and Di Benedetto, 2004). As discussed earlier; the new product involves an extensive development plans, considering both the aspects of present and new products and markets to place in the market in the successfully. But in case of existing product it has edgeSource: Harvard Business Review over the new products as it already holds the earned market share and the awareness. But to boost the performance of the existing products; organizations re-launch and redesign, which creates atleast three key differences than that of the new product development. For a company to expand with its existing product; Market penetration is the least risky key to adopt. As the penetration happens when a company enters the market with existing product, the first approach is to do the poaching of the competitors’ client base.Further it can attracts the non users and the existing users to increase the usage by means of promotional activities and hi ghlighting the enhanced attributes the will make the life of the new and existing users’ life better. This is the key of existing markets and existing products. In case of an existing product; the key of the Market development can help the same to fit in and create new segments with its established brand image, like Lucozade shifted from the sick children target segment to the athletes.Here the market was not new; but the company, which got into motion with time. Companies can use the key of Product development too, where the market exists but the product is new, though for the company; not for the market as the presence of other brands have made the product an existing one, the organization is venturing with its version to squeeze more revenue from the old product too (Ansoff, 1957). The conclusive step of the entire development process circles around the factors that govern the proposed product.The stand alone product like data card should concentrate on the concept evaluat ion measuring the technical and the marketing factors to know the rank of the product at the present state. It controls the financial issues too including the tariff to stand the competition. As the proposal has been made after the initial stages of the developmental process, it becomes more focused, which leads to stage commercialization.In the technical development task it undertakes the responsibilities of the protocols of the prototype and the production line up to make it eventually ready to scale up at the time requirement and subsequently to market the product proposed. Besides, marketing strategies holds plans for business proposals, product augmentation and launch the marketing activities to complete the process of proposed product designe. Reference Ansoff, I. (1957). Strategies for Diversification. Harvard Business Review, 35, 5, 113-124. Crawford, M. and Di Benedetto, A. (2004). New Products Management. (7th ed). New York: The McGraw-Hill Companies. Pulos, A.J. (1988). The American Design Adventure 1940-1975. Cambridge, Massachusetts: MIT Press. Ulrich, K.T. and Eppinger, S.D. (2004). Product Design and Development (3rd ed). New York: McGraw-Hill. Ullman, D.G. (2009). The Mechanical Design Process (4th ed). New York: McGraw-Hill.