Denture Adhesives in Prosthodontics- An Overview

Denture Adhesives in Prosthodontics- An Overview Dr Ranjith Kumar P, MDS; Dr Shajahan PA,MDS ; Dr Jyothis Mathew, MDS ABSTRACT Denture adhesives are used by an endless number of denture wearers and also by the dentists who fabricate them. Prescribing denture adhesives has been viewed by many prosthodontists as a means of compensating for deficiencies in clinical and technical procedures. Denture adhesives increase retention and thereby improve chewing ability, reduce wobble, improve comfort and confidence and reduce amount of food particles collecting under the dentures. Moreover, they undoubtedly provide the patients an increased sense of security and satisfaction. However, patients should use denture adhesives only on the advice of their dentists. INTRODUCTION Though their usage dates back to the late 18th century, they were first mentioned in dental literature in the 19th century. Earlier adhesives, formulated by mixing vegetable gums absorbed moisture from the saliva and swelled to a mucilaginous substrate that adhered to the mucosa of the mouth and the denture. Kapur’s 1 study in 1967 on 26 denture wearers, concluded that denture adhesives increased denture retention, thereby improving denture wearers’ incisive ability. Stafford and Russell, 2 using radio telemetry, measured the change in pressure, at the denture base-mucosa interface, with and without adhesives and found that denture adhesives allowed greater total occlusal pressure. The denture adhesives improved denture retention and stability (Tarbet et al 3), and found that patients perceived improved chewing ability, confidence and comfort, reduced wobble and collection of food particles under denture. Chew et al 4 determined the effectiveness of denture adhesive in improving the retention and stability of the complete maxillary denture in vivo using Kinseography. Abdelmelak and Michael 5 suggested that the denture adhesives acts as a cushion under complete denture; reducing the transmission of pressure and friction to the underlying mucosa. COMPOSITION The major constituents of denture adhesives can be broadly divided into three groups.6 Group 1 (Adhesive agents): Tragacanth, acacia, pectin, gelatin, methyl-cellulose, hydroxyl-methyl cellulose, Karaya Gum, sodium carboxyl-methyl cellulose and synthetic polymers (polyethylene oxide, acrylamides, acetic and polyvinyl). Group 2 (Anti-microbial agents) Sodium borate, sodium tetraborate, hexachlorophene and ethanol. Group 3 (Other agents) Plasticizers, wetting agents and flavouring agents such as oil of wintergreen, oil of peppermint, etc. Mechanism of Action Denture adhesives are supplied as paste, powder or cream. As the Adhesive powders absorb water, they swell to many times their original volume and the resulting anions are attracted to cations in the mucous membrane proteins. Sticky saliva thus formed increases the viscosity of the adhesive, thereby increasing the denture retention.7 Newer adhesive materials provide stronger bio-adhesive and cohesive forces. Free carboxyl groups formed by the hydration of adhesive such as methyl cellulose, hydroxyl methyl cellulose, sodium carboxyl-methyl cellulose or poly methyl vinyl-ether maleic anhydride (PVM-MA), etc. form electrovalent bonds that produce stickiness or bio adhesion. The increased viscosity of the adhesive creams result in their lateral spread excluding air and saliva thereby increasing the retention 8. Requirements of an ideal Denture Adhesive 9 Available as gels, creams and powders. Nontoxic, non-irritant, and biocompatible with the oral mucosa. It should have a neutral odour and taste. Easy application and removal from the tissue surface of the denture. Discourage microbial growth. Adhesiveness should be retained for 12-16 hrs. Increase the comfort, retention and stability of the denture Mode of application: Any residual adhesive should be removed from the tissue-bearing surface of the denture . The denture bearing tissues are wiped clean of any food debris. Wet dentures before application of adhesive. Small amounts of adhesive is applied to the tissue-bearing surface of denture. In the maxillary denture -Anterior alveolar ridge, the center of hard palate and posterior palatal seal region . In the mandibular denture apply to the sulcus of denture over the crest of the ridge extending from the anterior region sulcus to the distal extension. Denture should be seated and held in place firmly by hand pressure for 5-10 seconds. Gauze is used to remove excess adhesive . Patient is advised to close into centric occlusion several times to spread the adhesive as a thin even layer. Indications. Recording jaw relations and denture try in should be done using stable and retentive bases. The use of denture adhesive can stabilize the trail denture bases which show inadequate retention and stability due to various reasons. Use of adhesive will improve the accuracy of the denture try-in, and also decrease the patient apprehension about the fit of the final prosthesis. Use of adhesives in patients with compromised denture bearing areas adds to their confidence thereby increasing the ability to adapt to the new prosthesis. Immediate denture get loosened soon due to soft tissue healing and bony resorption requiring relining, rebasing, or a new denture fabrication. A soft liner used to augment the retention; comfort and function during the interim period are aided by the use of a denture adhesive. Reduced clinical findings of ulcers, tissue irritation, compression, and inflammation of the oral mucosa of denture wearers were seen with concomitant use of adhesives. Xerostomia in denture wearers either drug or radiotherapy induced can be alleviated with the use of denture adhesives. Stabilization of dentures in patients with hormonal changes and neuromuscular disorders such as myasthenia gravis, Parkinson’s and Alzheimer’s disease, etc., can be achieved with denture adhesives. Prosthesis to rehabilitate gross maxillofacial defects requires denture adhesives for retention. Denture adhesives are valuable adjuncts to the retention of radiation carriers or radiation protection prostheses. Usage of minimal amounts of adhesives provides high profile patients like attorneys, executives, speakers, etc. with psychological security in social situations. Contraindications Allergies to denture adhesives or any of its components. Gross inadequacies in retention and function. Excessive bone resorption and soft tissue shrinkage leading to loss of vertical dimension. Adhesives should not be used to retain fractured dentures or dentures with missing flange or with sectional fractures. Patients with inability to maintain proper hygiene of the denture should avoid use of denture adhesive. Conclusions Denture adhesives, when used properly are safe and beneficial to the patient in increasing retention and stability, enhanced comfort, improved function, and in providing psychological satisfaction. They should not be used as an aid to compensate for denture deficiencies even though adhesives enhance denture performance. Patients should not use denture adhesives inadvertently without proper guidance and instructions from the dentists.

Lewis Carrolls Alice’s Adventures in Wonderland Essay -- Alice Wonder

Lewis Carroll's Alice’s Adventures in Wonderland Philosophy – a subject that had driven people insane for as long as humans know their history. All the time people try to find a meaning, and later controvert it. For example, critics view a novel by Lewis Carroll Alice’s Adventures in Wonderland, as a quest for maturity story, Carroll’s view on Victorian Society and even existential meaning on life. All of those interpretations come from philosophical â€Å"drive† of the critics. The truth is that anyone can point a finger at the book and come up with their own â€Å"deep† meaning of the story, but if one looks at facts, well known, and obvious things – it is clear that the story is simply a children tale intended for entertainment and nothing more. Of course there is no sure way to prove that Carroll did not intend any deeper meaning into the story, after all, he was a mathematician and a man of great knowledge of children (19th Century Literature Criticism 105), but lets take a look at the most obvious fact – the time, place and audience of the original story of Alice in Wonderland. Here are the words of Lewis Carroll as he recalls that day: Full many a year has slipped away, since that â€Å"golden afternoon† that gave thee birth, but I can call it up almost as clearly as if it were yesterday – the cloudless blue above, the watery mirror below, the boat drifting idly on its way, the tinkle of the drops that fell from the oars, as they waved so sleepily to and fro, and (the one bright gleam of life in all the slumberous scene) the three eager faces, hungry for news of fairyland, and who would not he say ‘nay’ to: from whose lips ‘Tell us a story, please,’ had all the stern immuta bility of Fate! The â€Å"three eager faces† Carro... ...per and deeper for an idea. Works Cited: Carroll, Lewis. Alice’s Adventures In Wonderland & Through The Looking-Glass Signet Classic New York, NY 1960. Cohen, Morton. Lewis Carroll: A Biography Alfred A. Knopf New York, NY 1996. England in Literature: MacBeth Edition: Teacher’s Supplement Chapter 8, â€Å"Alice in Wonderland† 144-146. Scott Foresman & Co. 1973. Gattegno, Jean. Lewis Carroll: Fragments of a Looking-Glass â€Å"Alice† and â€Å"A Carroll Chronology† 4-27. Thomas Y. Crowell Co. 1973 New York, NY. Hudson, Derek. Lewis Carroll â€Å"Alice† 124-149. Folcroft Library Editions 1976. Kelly, Richard. Lewis Carroll â€Å"Alice† 78-97. U of Tenn. Twayne Publishers, G. K. Hall & Co. Boston, Mass 1977. Nineteenth-Century Literature Criticism, Vol. 2 â€Å"Lewis Carroll (1832-1898)† 105-121. Rackin, Donald. Alice’s Journey to the End of Night 132-143 MLA 1966.

Medicines and drugs Essay

A drug or medicine is a chemical that alters incoming sensory sensations, mood or emotions, or physiological state. Painkillers, hallucinogens and alcohols are examples of drugs and medicines that alter incoming sensory sensations. Prozac and alcohol alter mood or emotions Steroids, cigarettes and heart medicines alter physiological state, including consciousness, activity level or coordination. Drugs such as antiseptics, antibiotics and antivirals are infection fighters; hormones and vitamins affect body chemistry or metabolism; stimulants, depressants, analgesics and anesthetics affect the central nervous system and the brain. It is also important to understand that the human body has great natural healing processes; some drugs just increase the rate of natural healing. Also, there could be a placebo effect, it is when a pharmacologically inert substance that make seems to help because the person taking the substance was told that it would work. Placebo effect is examined by giving sugar pills to one group of tests patients, and real drugs to another group (when they are not aware of which they receive). B.1.2: Outline the stages involved in research, development and testing of new pharmaceutical products. This takes a very long time and costs a fortune, and is often controlled by the government. Before drugs are tested on humans, they must be testing on various animals (start with small animals and then go to bigger ones). The range of effective doses, the doses in which side-effects arise and the lethal doses have to be determined. There are 3 phases then; clinical trial; clinical evaluation (more in depth analysis); human studies with more evaluation, Very few drugs make it to the market, and the development would have cost a lot. Sometimes, things can still go wrong, like Thalidomide. It was given to pregnant women to treat morning sickness, but it cause deformities in babies! Now it is still used, but to treat skin sores. B.1.3. Describe the different methods of administering drugs * Oral: Very convenient. However, it might not be reliable as the rate of absorption depends on drug concentration, stomach content and pH value. As most is absorbed in the small intestines, so the drug must survive the gastric acid. Therefore it often lays in time release capsules. * Rectal: Good when drug cannot be taken orally due to vomiting or because the drug is pH sensitive. * Inhalation: Rapid, as there are loads of blood vessels in the lungs, and therefore a drug would have a reliable effect. Good for general anaesthesia, and asthma medicine. * Parental o Just below the skin; slower than for intravenous. Used often for dental injections o Into muscles; for large doses, or when immediate response is not needed (vaccines etc). o Intravenous; almost instantaneous, but cannot be undone when injected! Fatty lipids may bind some kinds of drugs, so the drugs won’t leave the body so fast The half life of a drug is the time for half the dose in the body to be eliminated. B.1.4. Discuss the terms lethal dosage (LD50), tolerance and side effects. LD50 is the lethal dose for 50% of the population; and it varies a lot from drug to drug. When one is tolerant, then one has to take a larger dose in order to feel the wanted effects. Some people after often use of a drug becomes dependant on it; physically (they must have it to be able to function physically) or psychologically (they must have it to feel right). Tolerance doesn’t necessarily mean that one gets used to the harmful effects. Sometimes it is hard to know the difference between main effect and side effect. A drug has many effects, and some patients benefit from a few of those effects; then those are the main effects, and all the other are side effects. Someone else, with another disease may benefit from other effects, and then those become the main effects. There are always harmful effects too. The risk : benefit ratio should also be considered. B.2.1. State and explain how excess acidity in the stomach can be reduced by the use of different bases. Bases, most often metal oxides, hydroxides, carbonates or hydrogen carbonates are used as antacids. These react with acid in the stomach to adjust the pH value. The purpose of gastric acid is to kill off bacteria, and help in digestion. However, over-eating or stress stimulates more production of acid, causing discomfort. The active ingredients tend to be; this react only with HCl: Magnesium Oxide: Magnesium Hydroxide: Aluminium Hydroxide: Calcium Carbonate: Sodium Hydrogen Carbonate: Magnesium Trisilicate: Some of the products; Carbon dioxide is a gas. So a foaming agent has to be added to prohibit excessive belching. Also alginates are used, to prevent acid reflux. If too much antacid is used, the stomach becomes too basic, and that hurts too; then more antacid might be wrongly taken. This leads to alkalosis. B.3.2. Describe the use of derivatives of salicylic acid as mild analgesics and compare the advantages and disadvantages of using aspirin and paracetamol (acetaminophen) Salicylic acid is used as an anti-pyretic (fever reducer) and mild analgesic (painkiller), but it is a strong acid and hurts the stomach and mouth; so variations of salicylic acid was used. One is Acetyl Salicylic Acid (ASA) or Aspirin, which has the benefits of salicylic acid and does not irritate so much due to the acetyl group. When ASA reacts with water, it becomes salicylic acid, and the by-product of ethanoic acid. GOOD: It is good for killing minor pain, reducing fever, acting as an anti-inflammatory agent and prevents abnormal blood clot. BAD: Upsets stomach and bleeding; allergy; accidental poisoning in infants and Reye’s syndrome. Acetaminophen is also an anti-pyretic and analgesic. However it does not upset the stomach and is safe. However, overdose can still occur and lead to liver and brain damage. And it is not anti-inflammatory. Ibuprofen is like aspirin and cause fewer stomach problems. It is anti-inflammatory and is very safe. B.3.3. Compare the structures of morphine, codeine and the semi-synthetic opiate heroin. These are strong analgesics and are often called opiates, narcotics or narcotic analgesics. The major pain relieving substance originates from the opium poppy plant is sleep inducing and pain relieving. All three share the same skeleton. Remember the group C2H3O2 is called an acetyl group. B.3.4. Discuss the advantages and disadvantages of using morphine and its derivatives as strong analgesics. These affects: The Central Nervous System, the Eye and the Gastrointestinal tract (the digestive system) They are used as: Strong analgesics (severe pain from injury and chronic diseases); treatment of diarrhoea, relieve coughing. However they are very addictive and are rather replaced with something else. They also produce mood changes, drowsiness and mental clouding. Tolerance can arise by adaptation of the liver and neurons in the brain. Some people can’t function without the drug, feeling restlessness, sweating, fever, chills, vomiting, aches etc due to abstinence of the drug. There is often severe psychological dependence too (one might feel extremely depressed).’à ¯Ã‚ ¿Ã‚ ½ Short term effects: Sedation, stupor, pain relief, euphoria, reduced tension, worry, couching reflex. One might die of overdose. Long term effects: Loss of appetite, sterility, withdrawal illness, crime, diversion of energy. B.4.1. Describe the effects of depressants Tranquilizers, sedatives and hypnotics, which calm and relax; they slow down heart rate and breathing. Tranquilizers include alcohol, Valium and Librium and are weaker than the others. These relieve anxiety and tension. Sedatives: Barbituates that soothe distress without producing much sleep in small doses. Hypnotics: Like chloral hydrate. These induce sleep. Too much can lead to coma or teach. B.4.2. Discuss the social and physiological effects of the use and abuse of ethanol. Social effects: Major costs from alcohol are from sickness and death, as in hospital treatments and lost efficiency. Property crimes and crimes against people; drinking while driving. Physiological effects: Harmful to relationships, and may physically or emotionally harm others. One may lose control and develop dependence and tolerance. It increases blood pressure when drinking and nausea, sweating and anxiety as withdrawal of use. Short-term effects: CNS depressant reduces tension. It triggers Euphoria, Talkativeness, Dilation of blood vessels, Violent behaviours, Inertia, Coma, Death. Long term effects: Cirrhosis, liver cancer, coronary heart disease, high blood pressure, strokes, gastritis, low birth mass etc. Alcohol can be used for antiseptics such as mouthwashes. B.4.3. Describe and explain the techniques used for the detection of ethanol in the breath of in the blood or urine. Ethanol passes from the stomach into the blood and therefore it passes into the lungs and ethanol vapour is formed. The breathalyser test might involve a redox equation with potassium dichromate: as oxidizing agent. Color change: Red-Orange to Green The gas liquid chromatography works as follows: Small samples of gases and volatile liquids such ethanol are separated. These are pushed through a column using an unimportant gas, such as Nitrogen gas and different gases take different time to come to the detector, where concentration of gases are measured. Intoxilyzer, Infra-red spectroscopy: Infra-red energy make molecules vibrate. Different types of bonds absorb and vibrate at different infer-red frequencies. By measuring how much energy is not absorbed by the molecules, one can find the number of certain bonds in the molecules. B.4.4. Describe the synergistic effects of ethanol with other drugs. Alcohol is easily absorbed in the stomach, so drugs that can be dissolved in alcohol will be absorbed much quicker, and the dosage will seem higher as in normal conditions the liver removes a part of the drug. So performance of the drug is enhanced and may lead to devastating effects such as death, especially if alcohol is combined with barbituates. Alcohol with aspirin increases the risk of stomach bleeding. B.4.5 . List other commonly used depressants and describe their structures. Valium (diazepam) is a tranquilizer, Mogadon (Nitrazepam) is a hypnotic drug (used to control seizures and infantile spasms), Prozac (hydrochloride) is an anti-depressant drug used to treat mental depression. Diazepam and Nitrazepam have similar carbon skeletons meanwhile Prozac is different. B.5.1. List the physiological effects of stimulants. Stimulants are chemicals that stimulate the brain and the central nervous system. It is the opposite of a depressant. These increase alertness. Examples are amphetamine, nicotine and caffeine. B.5.2. Compare amphetamines and adrenaline They both derive from the phenylethylamine structure, and therefore look similar. Furthermore, amphetamines mimic the effects of adrenaline (they are sympathomimetic drugs), as they constrict arteries and thus increases sweat production. They increase heart rate, blood pressure, respiration and insomnia. Medical uses: Treat mild depression, narcolepsy and asthma. They use up the body’s reserve energy and can lead to a collapse. B.5.3 Discuss the short- and long-term effects of nicotine consumption. Tobacco is a source of nicotine which is a mild stimulant with a short lived effect. The response is followed by depression and thereby makes one pushed to use it more often. Short-term: Increase in heart-rate and blood pressure. It constricts blood vessels and therefore strains the heart. Nicotine also reduces urine output. Long term effects of nicotine: It stresses hard and may lead to heart diseases and blood clot; May lead to increase of fatty acids in the blood. Smoking leads to more carbon monoxide in the blood making the blood less able to carry blood. It also increases the gastric acid production and may lead to ulcer. Smoking causes: Cancer in lungs and mouth; heart and blood vessel disease; breathing difficulties and chronic bronchitis; air pollution; fires; bad teeth; insomnia. B.5.4. Describe the effects of caffeine and compare its structure with that of nicotine. Caffeine stimulates the respiratory system (more energy is available from respiration), so heart and brain gets more energy. So one becomes more alert, motivated and well-being. In small amounts in is rather harmless, but too much causes insomnia. One gets more urine as well. Caffeine leads to some tolerance but no physical addiction. It can be given to babies to help their breathing. It also constricts blood vessels and therefore helps against migraines. Both caffeine and nicotine contain a tertiary amine group. Caffeine has more of those though. B.6.1. Describe the historical development of penicillins. In 1928, Fleming accidentally saw that some types of fungi killed off a certain bacterium and started to try to isolate the fungi, but it was too hard to purify it. In 1940, Floray and Chain continued with penicillin testing and development, and in 1943 it was available clinically. The first penicillin was Penicillin G. However it was deactivated by stomach acid so it had to be injected. Acid resistance penicillins such as penicillin V was developed by modifying the side chains of the basic penicillin structure. Some bacteria could deactivate penicillin G by synthesising an enzyme, therefore one had to make other synthetic penicillins. 6-APA penicillin is inert, but an extra amino group H2N would activate it. B.6.2. Compare broad spectrum and narrow spectrum antibiotics A broad spectrum antibiotics is effective against a wide variety of bacteria. Examples are tetracyclines. Narrow ones are effective only against certain types of bacteria; most penicillins are narrow spectrum antibiotics. One often has to determine the bacterium before getting antibiotics, because a broad-spectrum one can kill beneficial bacteria and give discomfort. B.6.3. Explain how penicillins work and discuss the effects of modifying the side chain. The cell walls of some bacteria are composed of polysaccharides, and these layers are supported by cross-links. However, penicillins interfere with the formation of these links and therefore weaken the structure. The bacteria can easily burst. Animals cells don’t have these cell walls and are therefore not affected. It is important to modify the side chain to work against bacteria have evolved and are able to break down certain types of penicillin. Side chains are also added to make the penicillin work (as for the 6-APA) and to survive the gastric acid (Penicillin G) B.6.4. Discuss and explain the effect over prescription of penicillins has, and the use of penicillins in animal feedstock Repeated use may lead to allergic reactions. They can also wipe out harmless and beneficial bacteria in the food canal, and harmful bacteria might eventually replace these. Bacteria can become resistant against certain antibiotics and then pass on their immunity. In feedstock: They are used to kill dangerous pathogens which may otherwise endanger humans and animals. They are also used to increase productivity. However, this increases the chances that bacteria might become resistant. B.7.1. State how viruses differ from bacteria Bacteria are relatively large single cell microorganism with DNA strands. Viruses are noncellular and are much smaller and are not living. They can only reproduce within a host cell. B.7.2. Describe the different ways in which antiviral drugs work * Block the transfer of genetic information * Control by inoculation, vaccines. * Block the enzyme activity in a host cell, so that the virus can’t use it to replicate. B.7.3. Discuss the difficulties associated with solving the AIDS problem HIV molecules bind to proteins on T-type of white blood cells and hinder them from fighting infections by inactivating them. HIV virus is good at mutating and together with their similarities with human cells, it is very heard to treat with antiviral drugs and vaccines. B.8.1. Describe the importance of geometrical isomerism in drug action. Stereoisomers are isomers with the same molecular formula and the same structural formula, but different arrangement of atoms in space. Geoemetric isomers have different physical properties such as polarity, boiling point, and solubility etc. They may also undergo different t chemical reactions although their functional groups are identical. For example cisplatin is en effective anti-cancer drug (as it may enter the nucleus of a cancerous cell), but the trans-isomers is inactive in such purposes. B.8.2. Discuss the importance of chirality in drug action. Optical isomers differ from geometric isomers in two ways: * Optical isomers are chiral (asymmetric) * Optical isomers are non-superimposable mirror images of each other One optical isomer rotates the plane polarized light one direction, meanwhile its other isomer rotates it the other way. An equi-molar mixture of two enantiomers means a 50-50 ration and will not totate the plane of polarised light at all; this is a racemic mixture. Penicillin V is active, but its enantiomer is inactive. One enantiomer of Thalidomide could be used to treat morning sickness in pregnant women and was marketed as a racemix mixture, but its other enantiomer gave foetal deformities. B.8.3. Describe the use of chiral auxiliaries to form the desired enantiomer. It is very heard to separate racemic mixtures into separate enantiomers, as they have identical chemical properties in relation to non-chiral reagents. Instead, scientists use stereospecific synthesis to produce only one kind of enantiomer. Chiral auxiliaries are used to convert non-chiral molecules into a desired enantiomer by attching itself chemically to the non-chiral molecule so that only one type of enantiomer can be formed. After the procedure the auxiliary can be recycled. This is used when synthesising Taxol which isa drug effective against breast cancer. B.8.4. Explain the use of combinatorial chemistry to synthesise new drugs. This is when one creates lots of molecules and test them quickly for biological properties; one starts with a set of basic chemicals which are then combined in all possible combinations, and this allows a fast production of many different molecules, increasing the chance of finding better drugs. A library is a collection of compounds that are screened to determine their usefulness as a drug, using parallel synthesis (identical processes with many different molecules at the same time). B.9.1. Compare local and general anaesthetics in terms of their modes of action Local anaesthetics block the pain in specific areas when they are injected under the skin or used as a crà ¯Ã‚ ¿Ã‚ ½me. Examples are cocaine, procaine, benzococaine, lidocaine etc. These block local nerve transmissions and decrease blood supply to that area. Procaine and lidocaine do not affect the brain, meanwhile cocaine does. General anaesthetics affect the brain and produce unconsciousness. But it is easy to reverse the unconsciousness. Examples are nitrous oxide, diethyl ether, chloroform, cyclopropane and halothane. B.9.2. Compare the structures and effects of cocaine, procaine and lidocaine. All three have the benzene ring and the tertiary amine. Cocaine also stimulates the central nervous system. It constricts blood vessels which leads to high blood pressure, and can’t be safely used. Although it doesn’t produce withdrawal symptoms and tolerance, it produces a strong psychological addiction. An overdose suppresses heart and respiration. Cocaine has a very short half life as it is metabolized by the liver fast, and is poorly absorbed when taken orally. Procaine gives prolonged relief from pain which is good for surgery and dental procedures. It is non-toxic and non-irritant. Lidocaine is used topically to produce numbness. It is more potent that procaine, but may cause swelling and itching. B.9.3. Discuss the advantages and disadvantages of nitrous oxide, ethoxyethane, trichloromethane, cyclopropane and halothane. Nitrous oxide is not very potent, and makes one feel good Trichloromethane is nonflammabe, but leads to liver damages. Narrow safety margin Ethoxyethane alleviates the pain in surgery well, but it is very flammable and nonstable. Cyclopropane is a very potent anaesthetics, however it forms explosive mixtures with air and is very flammable. It also causes vomiting and nausea. Halothane is widely used as it is not flammable and one may recover fast from it. It doesn’t irritate the respiratory tract. However, it takes time to become unconscious. It is potentially harmful to the ozone layer as it produces chlorine and bromine free radicals. B.9.4. Calculate the partial pressures of component gases in an anaesthetic mixture The partial pressure ratios of the total pressure equal the molar ratios of different gas molecules. It is important to have enough oxygen in the anaesthetic mixture so that the patient can live. At least 20% oxygen is needed B.10.1 Describe the effects of lysergic acid diethylamide (LSD), mescaline, psilocybin and tetrahydrocannabinol. Psychadelic drugs like these alter the mind and produces a change in thought, perception or mood and induce vivid fantasies. Colors seem more brilliant for the user. There are the effects of the mentioned mind altering drugs: LSD: This is a powerful hallucinogen that strongly magnifies perception and may destroy the sense of judgment. No physical addiction, and not very strong psychological dependence. Mescaline: Color hallucinations which last 12 hours. Psilocybin: Similar to LSD, especially at high doses, but at low doses produces relaxation. Shortlasting; 4 hours THC: Milder drug similar to alcohol. At larger doses, changes in perception occurs – sees bright colors and gets sharper hearing. May get extreme anxiety, depression, uneasiness, panic attacks etc. There is no tolerance, but could lead to psychological dependence. B.10.2 Discuss the structural similarities and differences between LSD, mescaline and psilocybin. LSD and psilocybin both have the Indole ring (Heterocyclic amine compound where the nitrogen atom is part of a ring). However, mescaline includes the benzene ring but not the indole ring; it does have a primary amine. Serotonin also has the indole ring. B.10.3 Discuss the arguments for and against the legalization of cannabis. Cannabis offers relief from symptoms from AIDS, cancer and glaucoma. Marijuana may increase the appetite, and relieves nausea. Cannabis helps terminally ill patients to relieve tension and anxiety. Marijuana relieves pressure inside the eyeball for glaucoma patients. However there are many bad sides to it too. Smoking marijuana may lead to lung problems and may suppress the immune system. It might lead to decreased fertility for men and cause brain damage and birth defects. Users may also start using harder drugs too. Users of prohibited drugs need to obtain it from criminal sources and may therefore be forced into crime to support their habit. It damages the society a lot.

Affection and sexuality Essay Example

Affection and sexuality Essay Example Affection and sexuality Essay Affection and sexuality Essay Essay Topic: The Second Sex Abused and neglected children have a more complex development than a normal child. There are two types of parent-child relationship that affects the development of abused and neglected children: conflict and neglect, and physical or sexual abuse. For the first type, the children develop impaired bonding, emotional deprivation and role reversal. For the second type, children develop impaired decision-making skills and imbalanced differentiation between affection and sexuality. Throughout the developmental stages from pregnancy and birth to the child’s growing up years, the parental and societal culture that the child needs to live up with brings conflicting values and meanings the child misinterprets and uses wrongly. During pregnancy and birth, the development is stunted because of the neglect of parents on the basic developmental needs of their child such as being cared for. The primary problem with an abusive parent is the desire for control. And because bringing a child into the world may cause disillusionment since they focus on how the child will love them not the other way around, the strain starts in the relationship. Aside from the mother’s changes in her perceptions and worldviews brought about by childbirth, the father also experiences the same changes. This can affect the relationship between the parents, which can affect that of the child’s relationship with his parents. Without a support system, parents fail to realize the much needed models for emulation of parenthood. Because these parents are so caught up with their expectations and needs, they tend to ignore or fail to realize the needs of their children, resulting to the child’s stunted development. The child’s ability to adapt and cope with his environment is based on how his environment treats him. Children learn by emulating what they see and if their environment is neglectful, then they will fail to develop the necessary qualities that will help them develop into better beings in the future. Abuse and neglect impede in necessary development of the child.

Making Salt essays

Making Salt essays The purpose of the lab was to determine how many grams of sodium chloride (salt) are produced when sodium carbonate is reacted with hydrochloric acid. This lab introduced many new tools to us. A lot of them we never used before and we had to be taught to use them in the proper manner. The tools used in this lab are: Ø Sodium Carbonate (about  ½ teaspoon) Ø Water, Paper Towels, Paper and pencil to record results There were 3 new items introduced during the process of this lab: Theoretical Yield is a calculated value for the amount of the substance that should be made after the reaction. We calculate this by using a conversation with mole ratios and molecular mass. Actual Yield is the amount of substance that is made after a reaction. You measure this amount after the entire reaction/experiment is complete. Percent Yield is the actual yield divided by the theoretical yield. Then, as in finding any percent, it is multiplied by 100. [(AY TY) * 100]. This is to determine how accurately the lab was performed. Begin by attaching the Bunsen burner to the gas outlet. Turn the gas on by twisting the lever until it is parallel with the outlet. Light the burner by flicking the Bunsen burner lighter right above the burner, repeat flicking until the flame is lit. With the piece on the bottom of the burner, you can turn it to adjust the flame. Adjust the flame to the correct height, which is just touching the bottom of the burners beaker holder on the top. Now take the evaporating dish and wash it with soap and water in the sink. Dry it off with some paper towels. Place the wire gauze screen on the top of the lit Bunsen burner. Place the washed evaporating dish on the top of the wire ga ...

Are Cell Phones Hazardous to Human Health Essay

Are Cell Phones Hazardous to Human Health - Essay Example In today’s world mobile phones has become a necessity. It is an inevitable truth that the mobile phone industry has taken everyone by a storm. The cell phones technology has been around for a long period of time, but it has only been the last fifteen years or so that it has been completely integrated into our lives to change the way we communicate with each other forever. The advancement of cell phones changed the entire social rules of human interactions. It has become so much a part of our lives that it is now impossible to live without a cell phone. It has indeed revolutionized the way we communicate with each other as talking to loved ones is now just a touch of our finger tips. Cell phone users increase rapidly and as of 2010, there were more than 303 million subscribers to cell phone service in the United States according to Cellular Telecommunications and Internet Association. It is beyond doubt that cell phones make our life more convenient, but behind these impressive gadgets we have a negative health impact which could be harmful for human beings. The issue of cell phones has been a long debated one and the phone radiation is still being questioned today. The effect of cell phone radiations and other related hazardous disease is the subject of hot topic debates these days due to the enormous increase in cell phone usage all over the world. Even though cell phones are very useful in today’s global world, several studies have suggested that continued usage of cell phones exposed human to electromagnetic fields which are associated with an elevated risks of cancer and other diseases. The issue of the harmfulness of cell phones is still questioned and many people also claimed that cell phones are not harmful to humans. People, who are of the view that cell phones are not dangerous to human beings, emphasized the fact that the negative impact of cell phones is just a myth created by the media. Many researchers have also claimed that cell phon es are not linked to cancer and that it is not dangerous to human health. â€Å"Using cell phones doesn't increase children's cancer risk, according to a new study, the latest in a series of papers that find no link between the phones and brain tumors† (Szabo, 2011). According to the Journal of the National Cancer Institute, children who used cell phones were not more vulnerable to develop brain tumor as compared to children who do not used cell phones. "Scientific evidence has overwhelmingly indicated that wireless devices do not pose a public health risk for adults or children," (Szabo, 2011). Many scientist are of the view that if cell phones are responsible for brain tumors, researchers would find the tumors on the side of the head where children hold their cell phones. But, this is not the case and moreover, scientist also noted that there has been no increase in brain tumors since cell phones were introduced to the mass population in the 1990. However, despite these cla ims, many researchers and scientists are still not convinced that there are no direct link to cell phones and other diseases. Despite the claim that cell phones are not dangerous to human beings, several researchers and scientist are of the view that cell phone are indeed dangerous for human beings. According to a research done by Lionel Bercovitch, cell phones are dangerous to human beings as the surface contains some metals such as nickel which can cause skin dermatitis on the users face. Nickel is considered to be the most common contact allergen. It is used by most of the cell phones manufacturer for accessorizing the phone. According to a research, nickel allergy affects up to 17 percent of women and 3 percent of men. This may be because of the fact that women talked more on cell phones and are likely to purchased more accessorized phones.

How has education and sports contributed to who you are today and how Essay

How has education and sports contributed to who you are today and how it will effect who you will become - Essay Example However, my academic life had not been affected by my participation in sports activities and competitions, because I always wanted to do well in both my studies and sports. The fact that I focused equally on sports and education helped me develop a high level of personal discipline from early years onwards. Since my parents allowed me to play when I was a small child, sports had in fact become a part of my daily life. I did learn to accommodate regular exercises and practice every day no matter how busy my schedule was. My school years did in fact provide me a lot of opportunities to be trained under excellent instructors. The special training programmes were very useful for me, and they were scheduled either early in the morning or in the evening, before or after class hours. Since I had been used to rigorous training programs since my early childhood, it was never a problem for me to dedicate quality time for academics and attend all the classes. In fact, the sport activities did help me develop a healthy mind in a healthy body, which did prepare me to utilize the maximum of time I had for my studies. I realized at school education was an integral part of my growth and development as an individual. I liked everything I was taught in the classrooms. I had been a diligent student who honors classes throughout high school and maintained a 2.5 average. I could connect well with all my teachers and be in jovial terms with my classmates. I learnt about the value of good friendship through my school years. Many of my friends did go out of their way to help me. They shared their class notes with me and spent time to explain the main points discussed in classes that I missed during sport competitions. I had been truly convinced of the relevance of all the subjects I had to study. I believe I have a very balanced personality thanks to my equal interest in