Monday, October 7, 2019
Business Case Study Example | Topics and Well Written Essays - 1000 words
Business - Case Study Example Since Carl was relatively new to the system, it was the duty of supervisor to monitor Carl and guide him towards the proper direction. The supervisor should also have offered assistance to Carl in terms of the orientation of the new employees. The next half of the project will present a brief background of the case. As offering a brief background to the case will help to understand the latter half of the report. Background It was during the early April when Mr. Carl Robins, the new campus recruiter of ABC Inc., hired 15 new employees. The employees were supposed to work for Monica Carrolls, who was the Operations Supervisor. After the process of recruitment Carl scheduled an orientation program for the newly recruited employees, which was supposed to take place on 15th June. His primary intention was to ensure that after providing adequate training to the staff, they will be fit for joining by the beginning of July. On May 15th, the operational supervisor, Monica Carrolls contacted C arl to discuss about the training sessions. Apart from that the discussion also took place about the schedule of training, medical checkup, physical test, orientation, handing over the policy booklets to the employees and a list of other issues. During the conversation Carl reassured Monica Carrolls that all the required amenities will be in place within the stipulated time frame. He also quoted that during the time employee orientation will commence every employee will be present along with their application forms. Carl got back to work just after the Memorial Day weekend, in order to check whether all the employee applications were completed or not. As he was going through it, he suddenly realized that there was a shortage of adequate pieces of the orientation manual. Moreover there were also missing pages in between the manual. After witnessing these occurrences, Carl become anxious when he comprehended that not a single newly recruited employees had received the obligatory drug screening. Apart from that Carl was shocked to know the news that the room where the training was supposed to take place was pre occupied by another client (Solve my question, 2012). Hence there was also unavailability of the training room. Key Problems The given case has to deal with a number of problems. The most important of them all is related to the way, campus recruiter Carl Robbins has planned, implemented and followed up. Mr. Robbins at first neglected to coordinate with his supervisor. This depicts that the recruiter feels himself as self sufficient. Apart from that he has misguided the employees as well as operational supervisor. He did not communicate the exact time, when the new employees will be attending the obligatory drug screening. He did not arranged adequate copies of orientation manual and also failed to fill up the applications of the newly recruited employees. Even the orientation manuals have few pages missing. This demonstrates how careless he was while perfo rming his duty. It also exhibits his lack of professionalism and responsibility. The recruiter also had enough time in order to make sure that everything would be in place prior to the commencement of the training schedule on the 15th of June. However, Carl was also new to the system and therefore it becomes the duty of the supervisor to train him or guide him
Sunday, October 6, 2019
The impact of Sports on Media Research Paper Example | Topics and Well Written Essays - 2500 words
The impact of Sports on Media - Research Paper Example Sporting events are frequently played on the media, and celebrated through advertisements and sponsorship. The way that sports are perceived is also a cultural phenomenon and as such this varies significantly depending on what part of the world is being examined. For example, Britain is well-known for behavior known as soccer hooliganism, which consists of violence occurring between soccer fans (Dunning, 2000). Although violence between fans is observed with other sports, such as the beating of fans (CBS News, 2011) in football (Roberts & Benjamin, 2000), the way that this occurs with soccer fans is unique, and can result in behaviors such as mobs of fans rushing the field (Dunning, 2000). Because of these differences, this paper will focus on the four major sports within North America, hockey, basketball, football and baseball, rather than considering sports globally. Both popular culture and the media are subject to two distinct, contradictory pressures. The first of these is the dissatisfaction with current forms of entertainment, and a desire to find new focuses, or to access a broader market. The second pressure is where people seek out the forms of entertainment that interest them, while avoiding those that do not. Sports have the potential to impact the media in either way. They could act as a unifying force, bringing together people with a wide range of different viewpoints. Alternatively, the media could treat sports as being a niche interest that is only a relatively small number of people care about. The purpose of this essay is to examine what effect sports has on the media, whether the media responses to sports are unifying or diversifying and if this changes depending on the type of sport or sporting event that is being shown. There is a substantial relationship between the media and sports within the United States, and the media has a
Saturday, October 5, 2019
The Role of Neurotechnology In Mitigating Developmental Progression of Research Paper
The Role of Neurotechnology In Mitigating Developmental Progression of Brain Disease - Research Paper Example One such condition which has been studied thoroughly is congenital diaphramatic hernia2. Of recent interest is fetal investigation and therapy of neurological disorders like spina bifida which are potential candidates for fetal therapy and there is some evidence that fetal interventions, when compared to postnatal interventions can improve postnatal neurological outcomes. This study aims to ascertain the role of neurotechnological advances in mitigation of the progression of neurological disorders, through review of suitable literature. Methods In order to retrieved articles for review, the electronic databases PUBMED and Google Scholar were used. The words used for search were â€Å"fetal therapy†or â€Å"fetal intervention†or â€Å"neurotechnology†with â€Å"brain disorders of fetus†. Several articles were displayed. Based on the contents of the abstracts, some of the articles were selected and studied. Both reviews and controlled studies were picked up for this research project to gain overall information about the topic and the research aim in study. Discussion Advances in technology in the form of powerful imaging strategies and improved sampling techniques have revealed the mystery of the fetus that was once secretive3. Most of the malformations that are diagnosed prenatally are managed best by appropriate medical and surgical therapy after birth. This may required planned delivery at a tertiary care after safe maternal transport. However, a few anatomic abnormalities with predictable consequences after birth may require surgical intervention before birth itself4 . In early 1980s, developmental pathophysiology of several anomalies which were potentially correctable was ascertained in animal models.5 The natural history of these diseases was determined through serial observation among animal models. Thereafter, selection criteria for prenatal intervention were developed. In the process, various anesthetic and tocolytic regime ns were refined and protocolised and also surgical aspects of hysterotomy and fetal repair were refined and developed. In the later stages, minimally invasive techniques for fetal intervention were developed and refined. All these advances in technology have benefited several fetal patients and it is hoped that more advances are made in this novel strategy allowing advanced forms of treatment on the fetus like tissue engineering, stem cell transplantation and gene therapy in both anatomic and non-anatomic defects (Harrison, 2003).6 During the previous decade, 3 important trends pertaining to fetal therapy have emerged for congenital diaphragmatic hernia7. In the first trend, the surgeons moved away from total surgical repair of the anatomical defect, especially in those liver herniation where repair was technically difficult, and developed induction of lung growth by
Friday, October 4, 2019
Problems of Moral and Social Values Essay Example for Free
Problems of Moral and Social Values Essay â€Å"According to the Greatest Happiness Principle, as above explained, the ultimate end, with reference to and for the sake of which all other things are desirable (whether we are considering our own good or that of other people), is an existence exempt as far as possible from pain, and as rich as possible in enjoyments, both in point of quantity and quality; the test of quality, and the rule for measuring it against quantity, being the preference felt by those who in their opportunities of experience, to which must be added their habits of self-consciousness and self-observation, are best furnished with the means of comparison. This, being, according to the utilitarian opinion, the end of human action, is necessarily also the standard of morality; which may accordingly be defined, the rules and precepts for human conduct, by the observance of which an existence such as has been described might be, to the greatest extent possible, secured to all mankind; and not to them only, but, so far as the nature of things admits, to the whole sentient creation†¦ (Mill, 1863)†           The quotation seemed to imply the thesis made by John Stuart Mill in Chapter 2 of his work Utilitarianism. As he explained the argument of the utilitarians, it was unintelligible for the opponents of the Theory of Utilitarianism to suppose that the principle that they advocate promote the concept of pleasure or that of happiness. The debate on the issue of quality and quantity as the indicator of the greatest utility was described by Mill as nothing but an interpretation of an irrational being. The end of the human conduct implied the standard of morality (Mill, 1863) thus it was meaningless to say that a person withheld his pursuit of happiness or pleasure for the promotion of the greatest utility. In this point, Mill contended that the greatest utility was indeed the same thing which gives the greatest happiness.            As consistently highlighted by the utilitarians, promotion of pleasure and aversion from pain were the only things that a man must take as his ultimate ends. In this way, what satisfied him or gave him happiness was the very thing that gave him the best utility. However, this argument was mistakenly interpreted by the adversaries of the Utilitarian principle by saying that not all men necessarily have the same regard to different objects of pleasure – meaning, their degree or intensity of being satisfied varied. Thus, the adversaries claimed, that the greatest utility for the greatest quantity was not practicable given that one may saw one thing as more valuable than other things while others saw these things as more important than the other one.            Mill attempted to correct this way of looking at the utilitarian principle by, again, applying the most notable comparison between swine or beast and man. Man was higher than the former since man had superior mental faculties which allowed him to judge rationally. He was not easily satisfied by less pleasurable things as how swine and beast would do. Man possessed â€Å"pride†and, much, â€Å"has sense of dignity (Mill, 1863).†He could not stand the case that his pleasures were as low or the same as the swine or beast. Hence, in some way, all men had the same faculties to judge between the lesser and the greater pleasure.            To support this, Mill insisted the role that the â€Å"habits of self-consciousness and self-observation (Mill, 1863)†played. Having the ability to observe, compare, and analyze the way things were presented to him, man could give his judgments on the issue raised earlier. There could be a case that a man would tend to be inclined with lesser pleasures than being in tuned with the greater pleasures but still at some point, man knew which of the pleasures weighs than the other. It was just his moral judgment was weaker and more prone to go before the bodily pleasures.            Mill furthered that this human ability to arrive at moral judgment could be compare with health. Mind and body comprised man. Both required the latter to pursue fuels that would maintain the stability of the two components. Nevertheless, to become healthy, man must be able to realize that the needs of the soul or the mind were far greater than needs of the body. Thus, man could only become healthy if he had successfully done this.            As a result, all men, who all had rational abilities to judge whether one thing had greater value than the other, would not say that the other thing possessed the greater value. This opened the idea that all men recognized things of greater value. They were indeed being urged by their body to choose the lesser pleasures but as a moral agent, they would easily be satisfied by those meager pleasures. Hence they would concur with the common good which offered the greatest good.            Mill’s last argument to support the theory of Utility as the appropriate standard of morality talked about the perceived impossibility to perform pure altruistic acts. Sacrificing one’s single happiness did not necessarily mean that his or her happiness was outweighed by others’ happiness. It only implied that he or she recognized that only by letting go of his or her personal interests that he or she could have achieved the greater happiness possible. And this greater happiness would not only benefit the majority but also himself or herself. Individual happiness then as Mill suggested, was not really neglected or taken for granted but was indeed reinforced by the attainment of the greater good for the greater number (which included the moral agent himself).            To reflect on the arguments raised by Mill, it was true that what made a pleasurable thing pleasurable was the amount of happiness one may get from it or the opportunity to prevent the existence of pain. Everyone would agree with such definition (except in the cases of a masochist which considered the feeling of pain as pleasurable). And since men has the power to make moral judgment which made him not to choose the lesser form of pleasures, his choice must have always on the level as how other rational beings would have.            Being with the choice of other rational beings, a moral agent would then recognize the need to uphold this choice for the achievement or maintenance of the greatest utility or the greatest happiness. Thus, he learned to put aside his lesser concerns to be able to prepare himself to do more elevated efforts for the betterment of mankind. Yet, this did not make him absolutely selfless. Whatever his efforts done even if these may appear for the benefit of other people, still he or she would receive something in return. And that explained his quest for the greatest utility. Reference: Mill, J.S. (1863). Utilitarianism. Aspen Publishers.
Thursday, October 3, 2019
Solid Dispersion System in Drug Delivery
Solid Dispersion System in Drug Delivery The oral route remains the preferred route of drug administration due to its convenience, good patient compliance and low medicine production costs. In order for a drug to be absorbed into the systemic circulation following oral administration, the drug must be dissolved in the gastric fluids. The active pharmaceutical ingredient in a solid dosage form must undergo dissolution before it is available for absorption from the gastrointestinal tract.1 Currently, approximately 40% of the marketed immediate release (IR) oral drugs are categorized as practically insoluble ( 1.1 Biopharmaceutics classification system The Biopharmaceutical Classification System (BCS) was introduced in the mid-1990s to classify the drug substances with respect to their aqueous solubility and membrane permeability. BCS is a useful tool for decision-making in formulation development from a biopharmaceutical point of view. Solubility improvement strategies are required for Class II and Class IV drugs. 1.2 Approaches to improve the solubility or to increase the available surface area for dissolution Physical modifications Particle size Micronization Nanosuspensions Modifications of the crystal habit Polymorphs Pseudopolymorphs (including solvates) Complexation/solubilization Use of surfactants Use of cyclodextrins Drug dispersion in carriers Eutectic mixtures Solid dispersions (non-molecular) Solid solutions Chemical modifications Soluble prodrugs Salts 1.3 Solid Dispersions The term solid dispersion refers to a group of solid products consisting of at least two different components, generally a hydrophilic matrix and a hydrophobic drug. The matrix can be either crystalline or amorphous. The drug can be dispersed molecularly, in amorphous particles (clusters) or in crystalline particles.7 Much of the research that has been reported on solid dispersion technologies involves drugs that are poorly water-soluble and highly permeable to biological membranes as with these drugs dissolution is the rate limiting step to absorption. Hence, the hypothesis has been that the rate of absorption in-vivo will be concurrently accelerated with an increase in the rate of drug dissolution. Therefore, solid dispersion technologies are particularly promising for improving the oral absorption and bioavailability of BCS Class II drugs. 1.3.1 Types of solid dispersions On the basis of release mechanisms and molecular arrangement in the matrix, solid dispersions are distinguished into following types9: A. Simple eutectic mixture: Eutectic mixture is prepared by rapid solidification of fused melts of two components that show a complete liquid miscibility with negligible solid-solid solubility. It involves loose atomic or molecular interaction and not on the formation of chemical bonds. When the eutectic mixture is exposed to gastrointestinal fluids, both the poorly soluble drug and the carrier may simultaneously crystallize out as a very small particles result in an increased the surface area and improved dissolution and absorption of the drug. B. Solid solution: A solid solution represents a homogenous one phase system, where the solid solution is dissolved in a solid solvent and the two components crystallize together. The solid solution achieves faster dissolution than a eutectic mixture because the drug particles in a solid solution are reduced to molecular size and dissolution of the drug takes place in the solid state prior to the exposure to the liquid medium. C. Glass solution: It is a homogenous glassy system in which a solute dissolves on glassy solvent results in increased dissolution and absorption of the drug. It is characterized by a transparency and brittleness below the glass forming temperature. Glass solution is a metastable and the strength of the chemical bonding is much less as compared to solid solution. Therefore, the release of the drug was found to be faster than a solid solution. D. Amorphous precipitations in crystalline carrier: An amorphous form of a drug produces faster dissolution rate. The drug may precipitate out in an amorphous form in a crystalline carrier from solid dispersions prepared by melting or solvent method. A strong interaction between the drug and carrier resulting in the formation of channels within the matrix seems to be a possible mechanism for improved dissolution of the drug. E. Compound or complex formation: The formation of a complex between the drug and the carrier may either decrease of increase the dissolution and the absorption rate of the drug. The formation of soluble complex with low association constant resulted in increased rate of dissolution and absorption. The enhancement in dissolution rate of the drug can be ascribed to An increasing solubility of the drug because of its amorphous state or small particle size (Kelvins law)9,10 An increased surface area available for drug dissolution because of the small size of the drug particles11,12 An improvement in wetting of the drug caused by the hydrophilic carrier13,14 1.3.2 Advantageous properties of solid dispersions Management of the drug release profile using solid dispersions is achieved by manipulation of the carrier and solid dispersion particle properties. Parameters such as carrier molecular weight and composition, drug crystallinity and particle porosity and wettability, when successfully controlled, can produce improvements in bioavailability.16 a. Particles with reduced particle size: Molecular dispersions, as solid dispersions, represent the last state on particle size reduction, and after carrier dissolution the drug is molecularly dispersed in the dissolution medium. Solid dispersions apply this principle to drug release by creating a mixture of a poorly water soluble drug and highly soluble carriers. A high surface area is formed, resulting in an increased dissolution rate and consequently, improved bioavailability. b. Particles with improved wettability: Strong contribution to the enhancement of drug solubility is related to the drug wettability improvement in solid dispersions. It was observed that even carriers without any surface activity, such as urea improved drug wettability. Carriers with surface activity, such as cholic acid and bile salts, when used, can significantly increase the wettability properties of drugs. Moreover, carriers can influence the drug dissolution profile by direct dissolution or co-solvent effects. c. Particles with higher porosity: Particles in solid dispersions have been found to have a higher degree of porosity. The increase in porosity also depends on the carrier properties, for instance, solid dispersions containing linear polymers produce larger and more porous particles than those containing reticular polymers and, therefore, result in a higher dissolution rate. The increased porosity of solid dispersion particles also hastens the drug release profile. d. Drugs in amorphous state: Poorly water soluble crystalline drugs, when in the amorphous state tends to have higher solubility. The enhancement of drug release can usually be achieved using the drug in its amorphous state, because no energy is required to break up the crystal lattice during the dissolution process. 1.3.3. Carriers used in solid dispersions Many carriers of natural, semi-synthetic and synthetic types are being used which include natural carbohydrates, semi-synthetic and synthetic hydrophilic polymers. S.No: 1 Nature of carrier: Sugars Name of the carrier: Dextrose, sorbitol, sucrose, fructose,maltose,galactose, xylitol, mannitol S.No: 2 Nature of carrier: Acids Name of the carrier: Citric acid, tartaric acid and succinic acid S.No: 3 Nature of carrier: Polymorphic materials Name of the carrier: Polyvinyl pyrrolidone (PVP), polyethylene glycols, hydroxyl propylmethylcellulose (HPMC), guargum, xanthan gum, sodium alginate, methyl cellulose, pectin, hydroxyl ethyl cellulose (HEC), hydroxyl propyl cellulose (HPC) and dextrins. S.No: 4 Insoluble or enteric Nature of carrier: polymer Name of the carrier: Hydroxy propyl methyl cellulosepthalate, eudragit RL, eudragit L 100, eudragit S100, eudragit RS. S.No: 5 Nature of carrier: Surfactants Name of the carrier: Polyethylene stearate, poloxamer 188, tweens and spans. S.No: 6 Nature of carrier: Miscellaneous Name of the carrier: Nicotinic acid, succinamide, dextrans, gelatin, poly vinyl alcohol, urea, cyclodextrins, skimmed milk etc., Table 1.2 Various carriers used in solid dispersions 1.3.4. Preparation techniques of solid dispersions The following are the major processes for the preparation of solid dispersions. A. Solvent evaporation method: In this method, the physical mixture of two components is dissolved in a common solvent and followed by the evaporation of solvent. The advantages of this method are low temperature requirements for the preparation of dispersion and thermal decomposition of drugs and carriers can be prevented. The higher cost of production, incomplete removal of solvent, adverse effects of solvent on the chemical stability of the drug and selection of common solvent are the drawbacks of this method. B. Melting method (Fusion method): The physical mixture of drug and water- soluble carrier was heated to melt and the molten mixture was then cooled and solidified mass was crushed, pulverized and sieved. The melting point of a binary system depends on its composition and proper manipulation of drug carrier ratios. Decomposition should be avoided due to fusion time and the rate of cooling. C. Kneading method: The physical mixture of drug and carrier were triturated using small quantity of organic solvent and water mixture, usually alcohol and water (1:1v/v). The slurry is kneaded for 45 minutes and dried at 45 °C. The dried mass is pulverized and sieved through sieve no. 60 and the fraction was collected. The advantages of this method are low temperature requirements for solid dispersion preparation and usage of organic solvent is less. This method of preparation avoids thermal degradation of drug and employs less quantity of organic solvents. D. Melting solvent method: This method involves dissolving the drug in a suitable solvent and the incorporation of the solution directly into the molten carrier. This method possesses the advantages of both solvent and melting methods. E. Supercritical fluid methods: Supercritical fluid methods are mostly applied with carbon dioxide (CO2), which is used as either a solvent for drug and matrix or as an antisolvent. This technique consists of dissolving the drug and the carrier in a common solvent that is introduced into a particle formation vessel through a nozzle, simultaneously with CO2. When the solution is sprayed, the solvent is rapidly extracted by the SCF, resulting in the precipitation of solid dispersion particles on the walls and bottom of the vessel. This technique does not require the use of organic solvent and since CO2 is considered environmentally friendly, this technique is referred to as solvent free. This technique is known as Rapid Expansion of Supercritical Solution (RESS). F. Lyophilization/ Freeze Drying: This technique is an alternative to the solvent evaporation method. Here the drug and carrier are dissolved in common solvent, frozen and sublimed to obtain a lyophilized molecular dispersion. G. Melt agglomeration process: This technique is used to prepare solid dispersion where a binder acts as a carrier. The solid dispersion is prepared by heating binder, drug and excipient to a temperature above the melting point or spraying the dispersion of drug in the molten binder on the heated excipients using a high shear mixer. The effect of binder type, method preparation and particle size are the critical factors influencing the solid dispersion preparation by this method. These parameters results in various dissolution rates, mechanism of agglomerate formation and growth, agglomerate size and distribution. 1.3.5. Limitations of solid dispersion systems: Problems limiting the commercial application of solid dispersions are: Laborious and expensive method of preparation. Reproducibility of physico-chemical characteristics. Difficulty in incorporating into the formulation of dosage forms. Crystallization of the amorphous drug in the dispersion. Poor scale up of manufacturing process and physical and chemical stability of drug and the vehicle. 1.4 FDTs: Fast-disintegrating and fast-dissolving tablets are becoming popular as novel delivery systems for drug administration. They are more convenient for children, elderly patients, patients with swallowing difficulties, and in the absence of potable liquids. The most desirable formulation for use by the elderly is one that is easy to swallow easy to handle. Taking these requirements into consideration, attempts have been made to develop a fast-disintegrating tablet. Since such a tablet can disintegrate in only a small amount of water in the oral cavity, it is easy to take for any age patient, regardless of time or place. For example, it can be taken anywhere at anytime by anyone who do not have easy access to water. It is also easy to dose the aged, bedridden patients, or infants who have problems swallowing tablets and capsules. Recently, many companies have researched and developed various types of fast-disintegrating dosage forms.18 These tablets display a fast and spontaneous de-aggregation in the mouth, soon after the contact with saliva, though they can be handled or extracted from the package without alteration. The active agent can thus rapidly dissolve in the saliva and be absorbed through whatever membrane it encounters, during deglutition, unless it is protected from pre-gastric absorption. To fulfill these requirements, tablets must be highly porous, incorporating hydrophilic excipients, able to rapidly absorb water for a rapid deaggregation of the matrix. Different technological techniques, such as freeze drying or molding or direct compression are currently employed to prepare the formulations of this type present on the pharmaceutical market. 1.4.1 Advantages of Fast Disintegrating Drug Delivery System (FDDS) 19,20 Ease of administration to patients who refuse to swallow a tablet, such as pediatric and geriatric patients, mentally ill, disabled and uncooperative. Convenience of administration and accurate dosing as compared to liquids. No need of water to swallow the dosage form, which is highly convenient feature for patients who are traveling and do not have immediate access to water. Good mouth feel property of FDDS helps to change the basic view of medication as bitter pill, particularly for pediatric patients. Ability to provide the advantages of liquid medication in the form of solid preparation. Rapid dissolution of drug and absorption, which may produce rapid onset of action. Some drugs are absorbed from the mouth, pharynx and oesophagus as the saliva passes down into the stomach; in such cases bioavailability of drugs is increased. Pregastric absorption can result in improved bioavailability and as a result of reduced dosage, improved clinical performance through a reduction of unwanted effects. 1.4.2 Approaches for fast disintegrating tablets A. Patented technologies Currently, four fast-dissolving/disintegrating technologies have reached the U.S. market: Zydis (R.P. Scherer, Inc.) WOWTAB (Yamanouchi Pharma Technologies, Inc.) OraSolv (Cima Labs, Inc.) DuraSolv (Cima Labs, Inc.) B. Three others are available outside the U.S. Flash Dose (Fuisz Technologies, Ltd.), Flash tab (Prographarm Group), OraQuick (KV Pharmaceutical Co., Inc.) Nanocrystal Technology C. Conventional technologies Freeze -drying or lyophilization Tablet Molding Direct compression Spray drying Sublimation Mass extrusion Direct compression It is the easiest way to manufacture tablets. Conventional equipment, commonly available excipients and a limited number of processing steps are involved in direct compression. Also high doses can be accommodated and final weight of the tablet can easily exceed that of other production methods. Directly compressed tablets disintegration and solubilization depends on the single or combined action of disintegrates, water soluble excipients and effervescent agent. Disintegrate efficacy is strongly affected by tablet size and hardness. Large and hard tablets have a disintegration time more than that usually required. As consequences, products with optimal disintegration properties often have medium to small size and /or high friability and low hardness. Breakage of tablet edges during handling and tablet rupture during the opening of blister, all results from insufficient physical resistance. Disintegrants have a major role in the disintegration and dissolution process of mouth dissolving Tablets made by direct compression. To ensure a high disintegration rate, choice of suitable type and an optimal amount of disintegrant is important. Other formulation components such as water soluble excipients or effervescent agents can further enhance dissolution or disintegration properties. But the main drawback of using effervescent excipients is their highly hygroscopic nature. The understanding of disintegrant properties and their effect on formulation has advanced during the last few years, particularly regarding so called superdisintegrants. Disintegration efficiency is based on a force equivalent concept, which is the combined measurement of swelling force development and amount of water absorption. Force equivalent expresses the capability of disintegrant to transform absorbed water into swelling force. The optimization of tablet disintegration was defined by means of disintegrant critical concentration. Below this concentration, the tablet disintegration time is inversely proportional to disintegrate concentration and above that disintegration time remains approximately constant or even increases. The simultaneous presence of disintegrate with a high swelling force called disintegrating agent and substances with low swelling force ( starch, cellulose and direct compression sugar) defined as, swelling agent was claimed to be a key factor for the rapid disintegration of the tablet, which also offers physical resistance. 1.4.3 Mechanism of tablet disintegration and water absorption When mouth dissolving tablets placed in the mouth, upon contact with saliva the tablet disintegrates or dissolve instantaneously. The mechanisms involved in the tablet disintegration mechanisms are Swelling Wicking (capillary) Deformation Particle repulsive forces Chemical reaction (acid base reaction) a. Swelling Not all disintegrates swell in contact with water swelling is believed to be a mechanism in which; certain disintegrating agents (like starch) impart their disintegrating effect. By swelling in contact with water, the adhesiveness of other ingredients in a tablet is overcome causing the tablet to disintegrate. b. Wicking (porosity and capillary action) Effective disintegrants that do not swell are believed to impart their disintegrating action through porosity and capillary action. Tablets porosity provides a way for the penetration of fluid into tablets. The disintegrants particles (with cohesiveness and compressibility) themselves act to enhance porosity and provide these capillaries into the tablets. Liquid is drawn up or wicked into these ways by capillary action and rupture the inter-particulate bonds causing the tablet to break into small parts. c. Deformation Starch grains are generally thought to be elastic in nature that is the grains that are deformed under pressure will return to their original shape when that pressure is removed. But, with the compression forces involved in tabletting, these grains are permanently deformed and are said to be energy rich with these energies being released upon exposure to water, that is the ability for starch to swell is higher in energy rich starch grains than in starch grains that have not been deformed under pressure. It is believed that no single mechanism is responsible for the action of most disintegrants. But rather, it is more likely the results of interrelationships between these major mechanisms. d. Due to disintegrating particle/particle repulsive forces: Another mechanism of disintegration attempts to explain the swelling of tablets made with non-swellable disintegrants. Guyot-Hermann has proposed a particle repulsion theory based on the observation that nonswelling particle also causes disintegration of tablets. The electric repulsive forces between particles are the mechanism of disintegration and water is required for it. Researchers found that repulsion is secondary to wicking. e. Chemical reaction (acid base reaction) Disintegration of tablet included with citric acid and tartaric acid along with the sodium bicarbonate, sodium carbonate, potassium carbonate; these react in contact with water to liberate carbon dioxide that disrupts the tablet. Name of the Product: Imodium Lingual Active Ingredients: Loperamide hydrochloride Dose: 2 mg Name of the Product: Pepcidin Rapitab Active Ingredients: Famotidine Dose: 20mg and 40 mg Name of the Product: Mosid MT Active Ingredients: Mosapride citrate. Dose: 2.5mg and 5mg Name of the Product: Calritin Reditabs Active Ingredients: Loratadine Dose: 10 mg Name of the Product: Nimulid MD Active Ingredients: Nimesulide Dose: 50mg and 100mg Name of the Product: Zyrof Meltab Active Ingredients: Rofecoxib Dose: 50 mg Name of the Product: Feldene Melt Active Ingredients: Piroxicam Dose: 10mg and 20 mg Name of the Product: Maxalt-MLT Active Ingredients: Rizatriptan Dose: 5mg and 10 mg Name of the Product: Pepcid RPD Active Ingredients: Famotidine Dose: 20mg and 40 mg Name of the Product: Zyprexa Zydis Active Ingredients: Olanzapine Dose: 5mg, 10mg, 15mg and 20 mg Name of the Product: Zofran ODT Active Ingredients: Ondansetron Dose: 4 mg and 8 mg Name of the Product: Remeron Soltab Active Ingredients: Mirtazepine Dose: 15mg, 30mg and 45 mg Name of the Product: NuLev Active Ingredients: Hyoscyamine sulfate Dose: 0.125 mg Table 1.3 Marketed fast disintegrating tablets Piroxicam, a non-steroidal anti inflammatory agent, belonging to BCS class II is widely used as a first line drug in the symptomatic relief of rheumatoid arthritis and osteoarthritis. Its low aqueous solubility has to be overcome through formulation strategies. Skimmed milk can be used as a drug carrier as it is inexpensive, easily available, biodegradable, and does not exhibit toxicity problems as experienced with PEG and PVP.24-26 Polymers as carriers also have limitations in enhancing  the  solubility of poorly soluble drugs due to their high viscosity. So the use of skimmed milk in the formulation of the SD of the drugs with limited aqueous solubility may be a potential and cost effective way to overcome the problem.27 Skimmed milk is a colloidal suspension of casein micelles, globular proteins and lipoprotein particles. The principal casein fractions are a-s1, a-s2, b-casein and k-casein. b-casein is amphiphilic and acts as a detergent molecule with surfactant property. The milk also contains whey proteins with principle fractions of the b-lacto globulin, a-lactalbumin, bovine serum albumin and immunoglobulins. These molecules were found to be surface active with a superior solubility than caseins.28 Aminoacids have been suggested either as additives in peroral application or in the form of aminoacid salts to reduce gastrointestinal disorders arising due to piroxicam like NSAIDs. The surface active agents and amino acid content are expected to be the reason for increased permeation of the drug from the solid dispersion.29,30
Wednesday, October 2, 2019
Interesting Facts of the Crucible :: Essay on The Crucible
Interesting Facts of the Crucible The Interesting Facts of The Crucible Was The Crucible, by Arthur Miller, just an â€Å"irrational fear?†(Arthur Miller’s The Crucible: Fact & Fiction Par.1). The panic of Communism during the Cold War and Senator Joseph McCarthy’s anti-communist hearings on February 3, 1953 led to this â€Å"irrational fear.†There are several major differences from the true version of the story and Miller’s version. These differences could have made the whole event much more interesting and eerie. Many specific details were overlooked that could have changed the play around. For example, Parris’ wife was not dead. In Miller’s play he refers to the group of girls as Abigail’s girls, but there were many other girls that were included in the group of the â€Å"afflicted†. Another difference that could have reconstructed how the play was is Abigail’s age. Because Miller used different context from the event, the true facts of history could have made the play muc h more interesting. In Miller’s play, Reverend Parris says â€Å"...my daughter...†(1.7). Reverend Parris mentioned he has a daughter and he is a widower. However, â€Å"Betty Parris’ mother was not dead, but very much alive at the time†(The Crucible: Fact & Fiction Para.5). Betty Parris’ mother really died 4 years after the events had taken place. This fact could have changed the total out-come of Miller’s play. If Betty had a mother figure, perhaps she would not have been lured into Abigail’s malicious ways. Since Abigail and Betty are cousins, Betty’s mother could have played as a mother figure for Abigail. Abigail would not have been such a troublemaker if she had a role model. This fact could have changed how Miller’s play was put together, and it could have made the play more interesting. In The Crucible, Miller mentioned that Abigail and her followers were just a bunch of teenage girls. In reality, Abigail’s group did not just consisted of teenage girls. Abigail’s afflicted group not only consists of teenage girls, but it consists of men and women. Some of the people from Abigail’s â€Å"afflicted†group are Sarah Bibber, John Indian, and Ann Putnam. The â€Å"afflicted†group could have consisted of many more people, and they could have had a bigger, stronger effect on the whole hype.
Lord of the Flies :: essays papers
Lord of the Flies Children all over the world hold many of the same characteristics. Most children are good at heart, but at times seem like little mischievous devils. Children enjoy having fun and causing trouble but under some supervision can be obedient little boys an d girls. Everybody, at one time in their lives, was a child and knows what it is like to have no worries at all. Children have their own interests and react to different things in peculiar and sometimes strange ways. For example, children are enchanted with Barney and his jolly, friendly appearance without realizing that he is actually a huge dinosaur. In the novel The Lord of the Flies, by William Golding, one can see how children react to certain situations. Children, when given the opportunity, wo uld choose to play and have fun rather than to do boring, hard work. Also, when children have no other adults to look up to they turn to other children for leadership. Finally, children stray towards savagery when they are w! ithout adult authority. Therefore, Golding succeeds in effectively portraying the interests and attitudes of young children in this novel. When children are given the opportunity, they would rather envelop themselves in pleasure and play than in the stresses of work. The boys show enmity towards building the shelters, even though this work is important, to engage in trivial activities. Af ter one of the shelters collapses while only Simon and Ralph are building it, Ralph clamours, "All day I've been working with Simon. No one else. They're off bathing or eating, or playing." (55). Ralph and Simon, though only children, are more mature a nd adult like and stray to work on the shelters, while the other children aimlessly run off and play. The other boys avidly choose to play, eat, etc. than to continue to work with Ralph which is very boring and uninteresting. The boys act typically of m ost children their age by being more interested in having fun than working. Secondly, all the boys leave Ralph's hard-working group to join Jack's group who just want to have fun. The day after the death of Simon when Piggy ! and Ralph are bathing, Piggy points beyond the platform and says, "That's where they're gone. Jack's party. Just for some meat. And for hunting and for pretending to be a tribe and putting on war-paint."(163). Piggy realizes exactly why the boys have gone to Jack's, which would be for fun and
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