BIM and Construction management Assignment Example | Topics and Well Written Essays - 1000 words

BIM and Construction management - Assignment Example The models created through BIM can be accessed by all concerned sides in the construction process for any adjustments or decision making in regard to how the construction work is to continue, how the building or facility will be used and if need be how demolition for the same will be done. It goes beyond the 2 dimensional representations of buildings on paper as plans, sections and elevations; and gives information about a building in three dimensions in addition to other details like light analysis, building components and their properties, quantities of building including excavation and spatial relationships (Kymmell, 2008). In order for information developed through this process to be useful, a BIM manager is contracted to advice contractors at every critical stage of a building life cycle. The roles of the BIM manager majorly revolve around collecting information on the whole process of construction and determine whether the work was accurately predicted in the BIM and points out what was not accurately presented in the models created. He is consulted in cases where actions or decisions contrary to what is on the models are advisable in order for the construction work to be completed in a manner that will not compromise the quality of a premise. Engineers or whoever is assigned the role of managing projects embrace BIM as it gives them many opportunities of illustrating to the funders of a project on the various options of doing work and the various implications for each alternative to help customers easily make decisions they are best comfortable with in regard to their financial capabilities. In addition through BIM the project managers are able to make accurate financial requisitions periodically as required. This is very helpful for subcontractors, or when finance is controlled from a central unit to avoid overspending. When a project adopts BIM in their work, there are so many benefits which come with it. Since the process emphasizes on information sha ring it becomes easier for managers to track the progress of the work as documented from time to time. The use of BIM helps mangers to make appropriate adjustments while the work is ongoing as it is able to reveal weakness within the structure that can make the building not to last for long. Since the purpose for which a building is constructed is the basis for determining accurately the various features in the building suitable for that purpose, it is possible to be able to design a structure that is ideal for maximum performance for the intended purpose. It is easy to control expenditure of resources throughout the project cycle since everything is budgeted for in advance and money for that particular purpose released in a timely manner for easy accountability. Any changes which contractors and subcontractors might consider necessary must be calculated and its appropriateness determined. Some of these measures, especially those being made in enhancing stability and durability of a building, are usually detected early and budgeted for through BIM. Therefore, any new requests for additional facilities must be weighted carefully because it is possible that what is

Specific problemsolving process Essay Example | Topics and Well Written Essays - 500 words

Specific problemsolving process - Essay Example To fail to plan is to plan to fail. As teacher, I have resources, associations and institutions to acquire the best syllabus and information. I have the contacts, connections, qualification, experience, creativity, and libraries memberships for reference and guidance. However, all these are of no use if I do not plan on their use in the course of my daily activities. My options do not exhaust with my professional resources. They extend to my personal dimension also. I have to constantly work and rework my mission goals, responsibilities, priorities, skills and abilities. I have to seek better results by my students, acquire skills and techniques to improve my communication skills, achieve promotions, keep track of my position in healthy competition, and above all fulfill my familial responsibilities. It is bound to provide me the necessary inputs and momentum to reach the top position in the institution where I work or in another similar institution. It will earn me more respect, improve my social and professional status and my earning capacity and perk, provide me more means to solve rudimentary as well as complex problems, and last but not the least, it will make me a better human being. Specific problem-solving process is an important tool for self-satisfaction and clients' satisfaction.

Monopoly - economics Essay Example for Free

Monopoly economics Essay In this chapter, look for the answers to these questions: ? Why do monopolies arise? ? Why is MR P for a monopolist? ? How do monopolies choose their P and Q? ? How do monopolies affect society’s well-being? ? What can the government do about monopolies? ? What is price discrimination? Economics PRINCIPLES OF N. Gregory Mankiw Premium PowerPoint Slides by Ron Cronovich  © 2009 South-Western, a part of Cengage Learning, all rights reserved 1 Introduction ? A monopoly is a firm that is the sole seller of a product without close substitutes. Why Monopolies Arise. The main cause of monopolies is barriers to entry – other firms cannot enter the market. Three sources of barriers to entry: 1. A single firm owns a key resource. E. g. , DeBeers owns most of the world’s diamond mines 2. The govt gives a single firm the exclusive right to produce the good. E. g. , patents, copyright laws 2 ? In this chapter, we study monopoly and contrast it with perfect competition. ? The key difference: A monopoly firm has market power, the ability to influence the market price of the product it sells. A competitive firm has no market power. MONOPOLY MONOPOLY 3 Why Monopolies Arise 3. Natural monopoly: a single firm can produce the entire market Q at lower cost than could several firms. Example: 1000 homes need electricity ATC is lower if one firm services all 1000 homes than if two firms each service 500 homes. MONOPOLY Monopoly vs. Competition: Demand Curves In a competitive market, the market demand curve slopes downward. But the demand curve for any individual firm’s product is horizontal at the market price. The firm can increase Q without lowering P, so MR = P for the competitive firm. 4 Cost Electricity ATC slopes downward due to huge FC and small MC ATC 500 1000 Q P A competitive firm’s demand curve $80 $50 D Q 5 MONOPOLY 1 10/23/2012 Monopoly vs. Competition: Demand Curves A monopolist is the only seller, so it faces the market demand curve. To sell a larger Q, the firm must reduce P. Thus, MR ? P. P ACTIVE LEARNING A monopoly’s revenue Common Grounds is the only seller of cappuccinos in town. The table shows the market demand for cappuccinos. Fill in the missing spaces of the table. Q 0 1 2 3 4 5 6 P $4. 50 4. 00 3. 50 3. 00 2. 50 2. 00 1. 50 7 1 TR AR n. a. MR A monopolist’s demand curve D Q MONOPOLY 6 What is the relation between P and AR? Between P and MR? ACTIVE LEARNING Answers Here, P = AR, same as for a competitive firm. Here, MR P, whereas MR = P for a competitive firm. Q 0 1 2 3 4 5 6 1 Common Grounds’ D and MR Curves P TR $0 4 7 9 10 10 9 AR n. a. $4. 00 3. 50 3. 00 2. 50 2. 00 1. 50 8 MR $4 3 2 1 0 –1 Q P MR $4 3 2 1 0 –1 $4. 50 4. 00 3. 50 3. 00 2. 50 2. 00 1. 50 0 $4. 50 1 2 3 4 5 6 4. 00 3. 50 3. 00 2. 50 2. 00 1. 50 P, MR $5 4 3 2 1 0 -1 -2 -3 0 1 2 3 Demand curve (P) MR 4 5 6 7 Q 9 MONOPOLY Understanding the Monopolist’s MR ? Increasing Q has two effects on revenue: ? Output effect: higher output raises revenue ? Price effect: lower price reduces revenue ? To sell a larger Q, the monopolist must reduce the price on all the units it sells. Profit-Maximization ? Like a competitive firm, a monopolist maximizes profit by producing the quantity where MR = MC. ? Once the monopolist identifies this quantity, it sets the highest price consumers are willing to pay for that quantity. ? Hence, MR P ? MR could even be negative if the price effect exceeds the output effect (e. g. , when Common Grounds increases Q from 5 to 6). 10 ? It finds this price from the D curve. MONOPOLY MONOPOLY 11 2 10/23/2012 Profit-Maximization 1. The profitmaximizing Q is where MR = MC. 2. Find P from the demand curve at this Q. Q Costs and Revenue MC The Monopolist’s Profit Costs and Revenue MC ATC P D MR Quantity As with a competitive firm, the monopolist’s profit equals (P – ATC) x Q P ATC D MR Q Quantity Profit-maximizing output MONOPOLY 12 MONOPOLY 13 A Monopoly Does Not Have an S Curve A competitive firm ? takes P as given ? has a supply curve that shows how its Q depends on P. A monopoly firm ? is a â€Å"price-maker,† not a â€Å"price-taker† ? Q does not depend on P; rather, Q and P are jointly determined by MC, MR, and the demand curve. So there is no supply curve for monopoly. MONOPOLY 14 CASE STUDY: Monopoly vs. Generic Drugs Patents on new drugs give a temporary monopoly to the seller. Price The market for a typical drug PM When the patent expires, PC = MC the market becomes competitive, generics appear. QM D MR Quantity QC MONOPOLY 15 The Welfare Cost of Monopoly ? Recall: In a competitive market equilibrium, P = MC and total surplus is maximized. The Welfare Cost of Monopoly Competitive eq’m: quantity = QC P = MC total surplus is maximized Monopoly eq’m: quantity = QM P MC deadweight loss Price Deadweight MC loss? In the monopoly eq’m, P MR = MC ? The value to buyers of an additional unit (P) exceeds the cost of the resources needed to produce that unit (MC). ? The monopoly Q is too low – could increase total surplus with a larger Q. ? Thus, monopoly results in a deadweight loss. P P = MC MC D MR QM QC Quantity MONOPOLY 16 MONOPOLY 17 3 10/23/2012 Price Discrimination ? Discrimination: treating people differently based on some characteristic, e. g. race or gender. Perfect Price Discrimination vs. Single Price Monopoly Here, the monopolist charges the same price (PM) to all buyers. A deadweight loss results. Price Consumer surplus Deadweight loss ? Price discrimination: selling the same good at different prices to different buyers. PM MC ? The characteristic used in price discrimination is willingness to pay (WTP): ? A firm can increase profit by charging a higher price to buyers with higher WTP. Monopoly profit D MR QM MONOPOLY 18 Quantity 19 MONOPOLY Perfect Price Discrimination vs. Single Price Monopoly Here, the monopolist produces the competitive quantity, but charges each buyer his or her WTP. This is called perfect price discrimination. The monopolist captures all CS as profit. But there’s no DWL. MONOPOLY Price Discrimination in the Real World ? In the real world, perfect price discrimination is not possible: ? No firm knows every buyer’s WTP ? Buyers do not announce it to sellers Price Monopoly profit ? So, firms divide customers into groups MC D MR Quantity based on some observable trait that is likely related to WTP, such as age. Q 20 MONOPOLY 21 Examples of Price Discrimination Movie tickets Discounts for seniors, students, and people who can attend during weekday afternoons. They are all more likely to have lower WTP than people who pay full price on Friday night. Airline prices Discounts for Saturday-night stayovers help distinguish business travelers, who usually have higher WTP, from more price-sensitive leisure travelers. MONOPOLY 22 Examples of Price Discrimination Discount coupons People who have time to clip and organize coupons are more likely to have lower income and lower WTP than others. Need-based financial aid Low income families have lower WTP for their children’s college education. Schools price-discriminate by offering need-based aid to low income families. MONOPOLY 23 4 10/23/2012 Examples of Price Discrimination Quantity discounts A buyer’s WTP often declines with additional units, so firms charge less per unit for large quantities than small ones. Example: A movie theater charges $4 for a small popcorn and $5 for a large one that’s twice as big. Public Policy Toward Monopolies ? Increasing competition with antitrust laws ? Ban some anticompetitive practices, allow govt to break up monopolies. ? E. g. , Sherman Antitrust Act (1890), Clayton Act (1914) ? Regulation ? Govt agencies set the monopolist’s price. ? For natural monopolies, MC ATC at all Q, so marginal cost pricing would result in losses. ? If so, regulators might subsidize the monopolist or set P = ATC for zero economic profit. MONOPOLY 24 MONOPOLY 25 Public Policy Toward Monopolies ? Public ownership ? Example: U. S. Postal Service ? Problem: Public ownership is usually less efficient since no profit motive to minimize costs CONCLUSION: The Prevalence of Monopoly ? Doing nothing ? The foregoing policies all have drawbacks, so the best policy may be no policy. ? In the real world, pure monopoly is rare. ? Yet, many firms have market power, due to: ? selling a unique variety of a product ? having a large market share and few significant competitors ? In many such cases, most of the results from this chapter apply, including: ? markup of price over marginal cost ? deadweight loss MONOPOLY 26 MONOPOLY 27 CHAPTER SUMMARY ? A monopoly firm is the sole seller in its market. Monopolies arise due to barriers to entry, including: government-granted monopolies, the control of a key resource, or economies of scale over the entire range of output. CHAPTER SUMMARY ? Monopoly firms maximize profits by producing the quantity where marginal revenue equals marginal cost. But since marginal revenue is less than price, the monopoly price will be greater than marginal cost, leading to a deadweight loss. ? A monopoly firm faces a downward-sloping demand curve for its product. As a result, it must reduce price to sell a larger quantity, which causes marginal revenue to fall below price. 28 ? Monopoly firms (and others with market power) try to raise their profits by charging higher prices to consumers with higher willingness to pay. This practice is called price discrimination. 29 5 10/23/2012 CHAPTER SUMMARY ? Policymakers may respond by regulating monopolies, using antitrust laws to promote competition, or by taking over the monopoly and running it. Due to problems with each of these options, the best option may be to take no action. 30 6.

Oil Blends Against Aedes Aegypti (Linn.) and Anopheles Dirus

Oil Blends Against Aedes Aegypti (Linn.) and Anopheles Dirus An in vitro study of the bioefficacy of essential oil blends against Aedes aegypti (Linn.)  and Anopheles dirus (Peyton and Harrison) by using membrane feeding apparatus Nutthanun Auysawasdi1, Sawitri Chuntranuluck1, Vichien Keeratinijakal2,  Siriporn Phasomkusolsil3 and Silas A Davidson3 Abstract This study was performed to determine the bioefficacy of plant essential oils on Aedes aegypti and Anopheles dirus. Repellency was determined by measuring reduction in feeding and mortality. A novel in vitro bioassay apparatus was developed that had a sausage-casing membrane feeding system. Mixtures of three essential oils were evaluated: turmeric (Curcuma longa), eucalyptus (Eucalyptus globulus), and orange (Citrus aurantium). The oils were mixed in pairs or all together at equal volume for a total of 10% volume and then formulated with 90% virgin coconut oil. Complete formulations were evaluated with and without an additional 5% vanillin. The formulations were applied to the sausage casing membranes and female mosquitoes provided (expose) blood meals (0.5, 1, 1.5, 2, 2.5, 3, 3.5 and 4 h) to assess the percentage repellency over time. The results showed that the strongest repellency was at shorter exposure periods. For Ae. aegypti, the strongest feeding reduction was with the turmer ic and eucalyptus combination and with the addition of vanillin (97.6-99.6%). For An. dirus, the strongest repellency was when all three oils were combined (98.4-99.6%). Vanillin increased the effects of repellency and mortality for all formulations and demonstrated an increased potential to enhance the bioefficacy of essential oil repellents. This study also demonstrated an in vitro membrane feeding system that can be used to screen essential oils. Keywords: Aedes aegypti, Anopheles dirus, Essential oil, Repellent, Membrane feeding system Introduction Mosquito-borne infectious diseases, such as dengue fever and malaria, are increasing each year, which may be due to the effects of global warming and climate change (Aguiar 2011). Dengue virus is primarily transmitted by Aedes aegypti (L.) mosquitoes and is the primary vector throughout the global distribution of dengue (Guzman et al. 2010). Malaria is transmitted by anopheline mosquitoes and the primary vectors are unique to different geographical locations. Anopheles dirus (Peyton and Harrison) is considered one of the most important vectors in Thailand and Southeast Asia (Sinka et al. 2011). Both of these diseases are difficult to manage because there are no available vaccines, and in the case of dengue, there are no therapeutic drugs (Halstead 2014). Efforts to control these diseases often focus on vector control and preventive strategies to minimize mosquito bites. The use of topical insect repellents applied to the skin is a proven method to reduce mosquito bites. There is a long history of using plant derived extracts to reduce mosquito bites. However, since the development of modern synthetic repellents in the 1940s, natural repellents have been largely replaced by synthetic chemicals (Debboun et al. 2006). Currently there is a renewed interest in using plant-based insect repellents due to concerns about safety and the preference for products that are considered more natural (Gerberg et al. 2007). Several essential oils and volatile compounds from a multitude of plants have been found to possess repellent properties against arthropods (Curtis et al. 1990). These plant derived chemicals often repel mosquitoes, but there is a wide variability between mosquito species (Kumar et al. 2011). Compounds that repel mosquitoes have been found in the following plant families: Graminae (Pushpanathan et al. 2006), Labiateae (Odalo et al. 2005), Lamiaceae (Ansari et al. 2000), Myrtaceae (Phukerd Soonwera 2014), Poaceae and Rutaceae (Trongtokit et al. 2005), Umbelliferae (Erler et al. 2006), and Zingiberaceae (Tawatsin et al. 2001). This study evaluated essential oils from the plants turmeric (Curcuma longa L., Family:Zingiberaceae), eucalyptus (Eucalyptus globulus Labill, Family: Rutaceae) and orange (Citrus aurantium L. Family: Myrtaceae). It is known that turmeric contains the chemical ar-turmerone that is repellent to arthropods (Su et al. 1982). The eucalyptus plant contains important active ingredient such as 1-8, cineole, ÃŽÂ ±- and ÃŽÂ ²-pinene that can repel various mosquito species (Yang et al. 2004). Mosquito repellents are often tested by using the arm in cage technique (World Health Organization 2009). This method allows mosquitoes to feed directly on human volunteers and has several disadvantages, such as the pain and discomfort associated with mosquito feeding, the requirement for Institutional Review Board (IRB) approval, the limited number of candidate repellents that can be screened at one time (Deng et al. 2014). Even though the direct evaluation of repellents on human skin remains essential for evaluating repellents, artificial membrane feeding systems can serve as a useful alternative when pre-selecting candidate repellents (Luo 2014). The use of artificial membrane feeding systems is largely dependent on the types of membranes, including animal tissues, Parafilm-M ® films, and collagen membranes (Friend Smith 1987; Pothikasikorn et al. 2010). This paper evaluated the efficacy of essential oils from turmeric rhizomes (TU), eucalyptus leaves (EU) and orange peels (OR). These oils were evaluated individually in a previous study using the arm in cage method compared to the synthetic repellent DEET (N,N-diethyl 1-3 methylbenzamide 25% w/w; KOR YOR 15) (Auysawasdi et al. 2016). This study looked at the same three chemicals but combined them in mixtures to determine if there was a synergistic effect. Also each mixture was evaluated with or without 5% vanillin extract. Vanillin was added because other studies have found that it extends the amount of time that certain natural products are effective against mosquitoes (Tawatsin et al. 2001). Materials and Methods Mosquitoes rearing Ae. aegypti and An. dirus were reared in the insectary of the Entomology Department, Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, Thailand. The photoperiod was maintained at 12 h light/12 h dark with a temperature of 25 ±2 °C and a relative humidity of 60-80%.Filter papers containing eggs of Ae. aegypti were placed in plastic trays (30ÃÆ'-35ÃÆ'-5 cm) with 2,500 ml of distilled water and larvae were provided fish food tablets (HIPPO ®). After one day, newly hatched larvae were diluted to about 500 larvae per tray for density and population. For An. dirus, approximately 150 eggs were added to a plastic tray and larvae provided fresh powdered fish food until pupation. The pupae of both species were collected and placed in holding cages until adult emergence. Freshly emerged adults were allowed to feed on soaked cotton pads containing a 5% multivitamin solution ad libitum. All testing was performed using five to seven day old post-emergent females that w ere denied sugar and only provided water for eight hours before testing. Preparation of plant essential oils Extracts from many of the plants are available commercially. Eucalyptus leaf oil (New Directions Aromatics Inc.,USA), Orange peel oil (New Directions Aromatics Inc., USA) and Vanillin (Borregaard Industries Ltd. Company, Norway) were purchased from Chanjao Longevity Co., Ltd., Bangkok, Thailand. Extracts from the turmeric plant were not available commercially. Therefore, turmeric rhizomes were collected from Suwan Farm, Pak Chong, Nakhon Ratchasima Province, Thailand. Essential oils were extracted by water distillation (Charles Simon 1990). The different essential oils were blended at equal ratios for a total volume of 10% and then mixed with virgin coconut oil (Agrilife Co., Ltd., Bangkok, Thailand) using a vortex mixer (Vortex-Genie ®2, Scientific Industries, Inc., USA) (Table 1). The coconut oil was chosen because it created a formulation similar to what would be applied to human skin. All formulations were kept at room temperature before testing. Repellency assay by feeding membrane apparatus Repellency of essential oil blends was examined for Ae. aegypti and An. dirus under laboratory conditions using a membrane feeding system.Fifty 5-7 day old female mosquitoes were selected and placed in plastic cups (8 cm dia. ÃÆ'- 8 cm high) covered with netting. A membrane feeding system was used with a sausage membrane stretched over a standard membrane feeder with a surface area of 3.14 cm2 (r=1) and secured with a rubber band. Before feeding, either 10  µl of each mixture or 10  µl of coconut oil (negative control) was pipetted onto the sausage-casing membrane and spread evenly with the tip of the pipette. The treated membranes were allowed to dry and mosquitoes provided blood meals (exposed) at eight different time intervals (0.5, 1, 1.5, 2, 2.5, 3, 3.5 and 4 hours) after application. A water feeding jacket was used to maintain the temperature of the feeding system at 37 °C. Approximately 1.5 mL of refrigerated (25 °C) human blood (Thai Red Cross Society, Bangkok, Thail and) was added to the glass feeder and allowed to warm to 37 °C. Then screened plastic cups of 50 female mosquitoes were allowed to feed for five minutes undisturbed. After the 5-min interval the membrane feeder was removed and unengorged mosquitoes were removed. Fully engorged mosquitoes and provided a sugar source and maintained in their containers in the insectary at 25 ±2 °C for 24 hours and then the number of dead mosquitoes counted. Data analysis Each mixture of essential oils was replicated five times (n=5) andresults presented as the mean  ± standard deviation (SD). To assess the significance of differences among groups, data were analyzed as a complete randomized design (CRD) with a one-way analysis of variance (ANOVA) followed by Duncans multiple range test (DMRT). A p-value of For comparison, percentage repellency was calculated for each test using the following formula: % Repellency = ÃÆ'- 100(1) Where A is the number of mosquitoes that did not feed on the treated membrane and B is the total number of mosquitoes exposed. Feeding was calculated as: % Feeding = ÃÆ'- 100 (2) Mortality was calculated as: % Mortality = ÃÆ'- 100(3) Mortality per hour = (4) Where D is the number of dead mosquitoes 24 hours after blood feeding, F is the total number of mosquitoes which fed on treated membranes, and h is the period of time that the extracts was left on the membrane. The number of mosquitoes which not feed on the membrane of each formulation was used to calculate the repellency per hour after application by the following formula: Repellency per hour = (5) Where A is the number of mosquitoes that did not feed on the membrane and h is the period of time that the extracts was on membrane. Results The efficacy of various formulations of selected essential oils (10% Total volume) with and without 5% vanillin, are presented in Figure 1. Shorter exposure times consistently resulted in lower feeding rates of both Ae. aegypti and An. dirus to all formulations. Feeding rates increased over time after application of formulations to the membranes. The addition of vanillin decreased feeding rates for all formulations. The greatest reduction in Ae. aegypti feeding was with the turmeric and eucalyptus mixture (TU:EU, Figure 1c). The greatest reduction in An. dirus feeding was with turmeric, eucalyptus, and orange mixed together (TU:EU:OR, Figure 1f). Mortality rates are also shown in Figure 1. Mortality rates were decreased based on time after application of formulations to the membranes. The greatest and most consistent mortalities for Ae. aegypti were the mixtures of TU:OR with and without vanillin (Figure 1a) and the mixture of EU:OR with vanillin (Figure 1d). The greatest mortality for An. dirus females was with the mixture of EU:OR with vanillin (Figure 1h). The percentage of repellency of all formulations against Ae. aegypti decreased with increasing exposure times (Table 2). The strongest percentage of repellency without vanillin was observed with the mixture of TU:EU (90.8-98.4%), followed by EU:OR (89.6-98.8%), and TU:OR (84.8-98.8%). The lowest percentage of repellency was observed for the mixture of all three plant extracts (TU:EU:OR, 81.2-94.8%). The percentage of repellency for all essential oil combinations with vanillin was not statistically different between any of the formulations without vanillin. The mixture of TU:EU provided the most repellency at 3.5 and 4 hours with and without vanillin. There were no statistical differences between the repellency of any formulations against An. dirus with or without vanillin, except for EU:OR+vanillin after 3 hours (Table 3). The highest percentage of overall repellency was observed for the combination of all three plant extracts (TU:EU:OR) and with the mixture of TU:OR. Overall, there were a positive correlation for formulations that produced the most repellency and increased mortality (Figure 2). For both Ae. aegypti (Figure 2a) and An. dirus (Figure 2b), the ratio of mortality per hour of formulations with vanillin was greater than without vanillin. Similarly, the repellency per hour of the four formulations with vanillin was stronger than without vanillin. Discussion Essential oils can have a significant effect on mosquito feeding rates (repellency) and mortality. For all formulations, exposure at 0.5 h after application of plant extracts to the artificial membrane resulted in greater repellency and higher mortality. Whereas, at 4 h after application there was increased feeding (decreased repellency) and lower mortality. These are consistent with many other studies demonstrating that plant extracts are volatile and lose their efficacy over time after application (Reifenrath Rutledge 1983; Rutledge Gupta 1999). The different mixtures led to different outcomes. The combination of TU:EU resulted in the highest repellency for Ae. aegypti, whilethe combination of all three essential oils (TU:EU:OR) gave the least repellency. Currently, the combination of all three extracts (TU:EU:OR) provided the greatest repellency against An. dirus. These results showed that the two mosquito species have different responses to the three plant-derived essential oils tested. It also demonstrated that the efficacy of each formulation is based on the compatibility of active ingredients and these compounds produce different effects when combined together. There are other reports showing that essential oils from plants are synergistic. Nerio et al. (2010) reported synergistic actions many plant essential oils used in this study that increased the repellency of formulations that would be expected from individual essential oils. Liu et al. (2006) found that the repellent activity of mixing essential oils from Japanes e mugwort (Artemisia princeps) and cinnamon (Cinnamomum camphora) was greateragainst Sitophillus oryzae and Bruchus rugimanus (Coleoptera: Curculionidae) than that elicited by individual oils. The results also showed that the addition of 5% vanillin significantly decreased feeding rates and increased mortality. Studies have shown that vanillin reduces the evaporation rate of active ingredients and therefore extends the protection time (repellency) (Tawatsin et al. 2001). It is believed that vanillin changes the volatile composition of essential oils and also has an effect on the gustatory processes of mosquitoes (Lee et al. 2010; Ali et al. 2012). In this study the effect of vanillin was often more evident at increased time after application. It is recommended that vanillin be considered included as an ingredient for future natural product repellents. Finally this study presented a unique method to evaluate repellent formulations using a sausage membrane casing as part of a membrane feeding system. The arm in cage method has been used to evaluate many essential oil formulations (Choochote et al. 2007). While the arm in cage method is the gold standard for evaluating repellents, a membrane feeding system offers several advantages in that it can be quickly performed, standardly replicated, and does not require human volunteers. (Huang et al. 2015; Cockcroft et al. 1998). This method could be developed to rapidly screen, evaluate, and select the most promising formulations before they are tested on human volunteers. Acknowledgments This study is a research collaboration between the Department of Biotechnology, Faculty of Agro-Industry, Kasetsart University, Bangkok, Thailand and the Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, Thailand. The authors are deeply grateful to the Armed Forces Research Institute of Medical Science (AFRIMS) for facilitating and supporting the research. Finally, the authors thank the insectary staff; Kanchana Pantuwattana, Jaruwan Tawong, Nantaporn Monkanna, Yossasin Kertmanee, Weeraphan Khongtak and Sakon Khaosanorh for teaching and supporting this work. The views expressed in this article are those of the authors and do not reflect the official policy of the Department of the Army, Department of Defense, or the U.S. Government. References   Aguiar M (2011) The effect of global warming on vector-borne diseases: Comment on Modeling the impact of global warming on vector-borne infections by E. Massad et al. Phys Life Rev, 8, 202-203. 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(2007) Repellent activity of selected essential oils against Aedes aegypti. Fitoterapia, 78, 359-364. Cockcroft A, Cosgrove J Wood R (1998) Comparative repellency of commercial formulations of deet, permethrin and citronellal against the mosquito Aedes aegypti, using a collagen membrane technique compared with human arm tests. Medical and Veterinary Entomology, 12, 289-294. Curtis C, Lines J, Lu B Renz A (1990) Natural and synthetic repellents. Appropriate Technology in Vector Control, 75-92[Elz Ã‚ ¤1]. Debboun M, Frances SP Strickman D (2006) Insect repellents: principles, methods, and uses, CRC Press. Deng W, Zhu N Mo J (2014) In vitro bioassay methods for laboratory screening of novel mosquito repellents. Entomological Science, 17, 365-370. Erler F, Ulug I Yalcinkaya B (2006) Repellent activity of five essential oils against Culex pipiens. Fitoterapia, 77, 491-494. Friend W Smith J (1987) The study of insect blood-feeding behaviour: 1. Feeding equipment, physical and endogenous factors, dose effect analysis, and diet destination. Memà ³rias do Instituto Oswaldo Cruz, 82, 11-17. Gerberg EJ, Novak RJ, Debboun M, Frances S Strickman D (2007) Considerations on the use of botanically-derived repellent products. In: Gerberg EJ Novak RJ (Eds.) Insect Repellents: Principles, Methods and Uses. Guzman MG, Halstead SB, Artsob H, Buchy P, Farrar J, Gubler DJ, et al. (2010) Dengue: a continuing global threat. Nature Reviews Microbiology, 8, S7-S16. Halstead SB (2014) Stumbles on the path to dengue control. The Lancet Infectious Diseases, 14, 661-662. Huang TH, Tien NY Luo YP (2015) An in vitro bioassay for the quantitative evaluation of mosquito repellents against Stegomyia aegypti (= Aedes aegypti) mosquitoes using a novel cocktail meal. Medical and Veterinary Entomology, 29, 238-244. Kumar S, Wahab N Warikoo R (2011) Bioefficacy of Mentha piperita essential oil against dengue fever mosquito Aedes aegypti L. Asian Pacific Journal of Tropical Biomedicine, 1, 85-88. Lee Y, Kim SH Montell C (2010) Avoiding DEET through insect gustatory receptors. Neuron, 67, 555-561. Liu C, Mishra A, Tan R, Tang C, Yang H Shen Y (2006) Repellent and insecticidal activities of essential oils from Artemisia princeps and Cinnamomum camphora and their effect on seed germination of wheat and broad bean. Bioresource Technology, 97, 1969-1973. Luo YP (2014) A novel multiple membrane bloodâ‚ ¬Ã‚ feeding system for investigating and maintaining Aedes aegypti and Aedes albopictus mosquitoes. Journal of Vector Ecology, 39, 271-277. Nerio LS, Olivero-Verbel J Stashenko E (2010) Repellent activity of essential oils: a review. Bioresource Technology, 101, 372-8. Odalo JO, Omolo MO, Malebo H, Angira J, Njeru PM, Ndiege IO, et al. (2005) Repellency of essential oils of some plants from the Kenyan coast against Anopheles gambiae. Acta Tropica, 95, 210-218. Phukerd U Soonwera M (2014) Repellency of essential oils extracted from Thai native plants against Aedes aegypti (Linn.) and Culex quinquefasciatus (Say). Parasitology Research, 113, 3333-40. Pothikasikorn J, Boonplueang R, Suebsaeng C, Khaengraeng R Chareonviriyaphap T (2010) Feeding response of Aedes aegypti and Anopheles dirus (Diptera: Culicidae) using out of date human blood in a membrane feeding apparatus. Journal of Vector Ecology, 35, 149-155. Pushpanathan T, Jebanesan AGovindarajan M (2006) Larvicidal, ovicidal and repellent activities of Cymbopogan citratus Stapf (Graminae) essential oil against the filarial mosquito Culex quinquefasciatus (Say) (Diptera: Culicidae). Tropical Biomedicine, 23, 208-212. Reifenrath WG Rutledge LC (1983) Evaluation of mosquito repellend formulations. Journal of Pharmaceutical Sciences, 72, 169-173. Rutledge L Gupta R (1999) Variation in the protection periods of repellents on individual human subjects: an analytical review. Journal of the American Mosquito Control Association, 15, 348-355. Sinka ME, Bangs MJ, Manguin S, Chareonviriyaphap T, Patil AP, Temperley WH, et al. (2011) The dominant Anopheles vectors of human malaria in the Asia-Pacific region: occurrence data, distribution maps and bionomic prà ©cis. Parasites Vectors, 4, 89. Spss I (2007) for windows, version 16.0. SPSS, Chicago, IL. Su HC, Horvat R Jilani G (1982) Isolation, purification, and characterization of insect repellents from Curcuma longa L. Journal of Agricultural and Food Chemistry, 30, 290-292. Tawatsin A, Wratten SD, Scott RR, Thavara U Techadamrongsin Y (2001) Repellency of volatile oils from plants against three mosquito vectors. Journal of Vector Ecology, 26, 76-82. Trongtokit Y, Rongsriyam Y, Komalamisra N Apiwathnasorn C (2005) Comparative repellency of 38 essential oils against mosquito bites. Phytotherapy Research, 19, 303-309. World Health Organization (2009) Guidelines for efficacy testing of mosquito repellents for human skins. WHO, Geneva, 4 Yang YC, Choi HY, Choi WS, Clark JM Ahn YJ (2004) Ovicidal and adulticidal activity of Eucalyptus globulus leaf oil terpenoids against Pediculus humanus capitis (Anoplura: Pediculidae). Journal of Agricultural and Food Chemistry, 52, 2507-11. [Elz Ã‚ ¤1]It has no volume

Toulmin Analysis of Attraction Essay -- essays research papers

Toulmin Analysis of â€Å"Attraction†   Ã‚  Ã‚  Ã‚  Ã‚     Ã‚  Ã‚  Ã‚  Ã‚  In â€Å"The Mystery of Attraction,† Harville Hendrix claims that attraction between human beings is based on a number of factors that ultimately leave human beings baffled on exactly how humans experience such intense emotions as seen in romantic love and why so many couples tend to have complementary characteristics. He supports this claim by explaining several theories of attraction. His biological theory of courtship states that â€Å"we instinctively select mates who will enhance the survival of the species† (483). This theory suggests instinctive evolutionary attraction such as a female’s rosy cheeks on a slender frame and a male’s muscular physique are the features which take paramount importance in mate selection. Another theory, which he calls the exchange theory, emphasizes that â€Å"we select mates who are more or less our equals† (483). This theory proposes the act of mate selection as being a game of weighing the po sitive and negative characteristics in hopes of attaining equality in all aspects of both mates. His final idea, which is called the persona theory, â€Å"maintains that an important factor in mate selection is the way a potential suitor enhances our self esteem† (483-484). Attraction as it pertains to this theory places emphasis on what others think and the image of how others perceive someone with a certain mate.   Ã‚  Ã‚  Ã‚  Ã‚  Hendrix’s argument has one warra... Toulmin Analysis of Attraction Essay -- essays research papers Toulmin Analysis of â€Å"Attraction†   Ã‚  Ã‚  Ã‚  Ã‚     Ã‚  Ã‚  Ã‚  Ã‚  In â€Å"The Mystery of Attraction,† Harville Hendrix claims that attraction between human beings is based on a number of factors that ultimately leave human beings baffled on exactly how humans experience such intense emotions as seen in romantic love and why so many couples tend to have complementary characteristics. He supports this claim by explaining several theories of attraction. His biological theory of courtship states that â€Å"we instinctively select mates who will enhance the survival of the species† (483). This theory suggests instinctive evolutionary attraction such as a female’s rosy cheeks on a slender frame and a male’s muscular physique are the features which take paramount importance in mate selection. Another theory, which he calls the exchange theory, emphasizes that â€Å"we select mates who are more or less our equals† (483). This theory proposes the act of mate selection as being a game of weighing the po sitive and negative characteristics in hopes of attaining equality in all aspects of both mates. His final idea, which is called the persona theory, â€Å"maintains that an important factor in mate selection is the way a potential suitor enhances our self esteem† (483-484). Attraction as it pertains to this theory places emphasis on what others think and the image of how others perceive someone with a certain mate.   Ã‚  Ã‚  Ã‚  Ã‚  Hendrix’s argument has one warra...

Jewish Ghettos Essay -- essays research papers

Jewish ghettos: The basic history of the formation of the Jewish ghettos, including the everyday life and economic hardships faced by the communities.   Ã‚  Ã‚  Ã‚  Ã‚  By definition, a ghetto is an area, usually characterized by poverty and poor living conditions, which houses many people of a similar religion, race or nationality. They served to confine these groups of people and isolate them from the rest of the community because of political or social differences. However, the Jewish ghettos established throughout Europe were more than just a way for the Germans to isolate the Jewish community. They were the first step in making Hitler’s final solution possible. The ghettos were the means of organizing all of the Jews together and preparing them to be shipped to concentration camps. However, these ghettos soon evolved into political, religious and social entities that served the community and began to resemble a form of self-ruling government. Furthermore, many of these ghettos were different from one another because of different internal structures of the Jewish community or the diversity of the personalities of the l eaders of the council in the Jewish community. However, the ghettos must be analyzed as if they are all â€Å"one history.†(Holocaust) In fact, many of the communities were the same with regards to Jewish perceptions and reactions concerning life and the difficulties being faced by each community in its occupied territory. This research paper discusses the common everyday trials and tribulations faced by all the ghettos and looks at the ghettos from a political and socio-economic point of view. (Holocaust)   Ã‚  Ã‚  Ã‚  Ã‚  First, it is important to understand the history behind the ghettos and discuss their centralization in Poland. Hitler incorporated the western part of Poland into Germany according to race doctrine. He intended that Poles were to become the slaves of Germany and that the two million Jews therein were to be concentrated in ghettos in Poland's larger cities. Later this would simplify transport to the death camps. Nazi occupation authorities officially told the story that Jews were natural carriers of all types of diseases, especially typhus, and that it was necessary to isolate Jews from the Polish community. Jewish neighborhoods thus were transformed into prisons. The five major ghettos were located... ... not go far enough to commit acts of terrorism simply because of Faith. Jihad, or holy war, is the sole emotion, not act, which strengthens the will to perform horrible crimes on humanity. Simply saying that a faith-based idea can go as far as the perpetrator is willing.   Ã‚  Ã‚  Ã‚  Ã‚  In conclusion, we have studied the history and present events surrounding the Holocaust. We have studied the ideology and the reasons behind both the Jewish and the German involvement. In the end, I found that I still feel the same way about the Holocaust that I did before taking this class. I think that it takes a certain kind of person to commit those murderous acts and the idea of â€Å"just following orders† is ridiculous because it assumes that free will is no longer considered strong enough to prevent the ordered killing of millions of people. The important aspects of today’s society in relation to the existence of God in our lives are disturbed by the lack of faith in God for not being around when his people are suffering the most. How can these acts, like the Holocaust and the genocidal feud in Rwanda, be analyzed without accepting the absence of God in relation to these events?

Logical Positivism Essay

Also known as logical empiricism, rational empiricism or neo-positivism, logical positivism is the name given in 1931 by A.E Blumberg and Herbert Feigl to a set of philosophical ideas put forward by the Vienna Circle. This Vienna Circle was a group of early twentieth century philosophers who sought to re-conceptualize empiricism by means of their interpretation of then recent advances in the physical and formal sciences. Hence, the Vienna Circle represented a radical â€Å"anti-metaphysical† stance which held the view that an empiricist criterion for meaning and a logicist conception of mathematics could prove the meaningfulness of statements (Stanford Encyclopaedia of Philosophy). Logical positivism is the school of thought that attempts to introduce the methodology and precision of mathematics and the natural science into the field of philosophy. The movement, which began in the early twentieth century, was the fountainhead of the modern trend that considers philosophy an analytical, rather than a speculative inquiry (Passmore). As a school of philosophy, logical positivism â€Å"combines positivism with a version of apriorism , that is, the view that holds that some propositions can be held true without empirical support† (Wikipedia Encyclopaedia). According to the Oxford Companion to Philosophy, the movement’s doctrine is ‘centred on the principle of verifiability. This holds the notion that individual sentences gain their meaning by some specification of the actual steps we take for determining their truth or falsity’. In essence, logical positivism seeks to verify the meaning in statements through empirical observations. Historical Background of Logical Positivism The position of the original logical positivists was a blend of the positivism of Ernst Mach with the logical concepts of Gottleb Frege and Bertrand Russell. But, their inspiration was derived from the writings of Ludwig Wittgenstein and G.E Moore. According to Passmore, in his article â€Å"Logical Positivism†, the logical positivists thought of themselves as continuing a nineteenth century Viennese empirical tradition, closely linked with British empiricism and culminating in the anti-metaphysical scientifically oriented teaching of Ernst Mach. He further pointed out that in 1907 the mathematician Hans Hahn, the economist and sociologist Otto Neurath and the physicist Phillip Frank, all of whom were later to be prominent members of the Vienna Circle, came together as an informal group to discuss the philosophy of science. In addition, Passmore posited that they did this in hope that they could ‘give an account of science to the importance of mathematics, logic and theoretical physics without abandoning Mach’s general doctrine that science is, fundamentally, the description of experience’ (par. 2). Subsequently, they adopted views from the â€Å"new positivism† of Poincare and coupled it with Mach’s views in an attempt to anticipate the main themes in logical positivism (par. 2). Logical Positivists view of Traditional Philosophy The philosophical position of logical positivism in its original form was the outcome of the profoundly incisive influences of Wittgenstein and Moore (Runes 359). Logical positivists were concerned about the soundness of metaphysics and other traditional philosophy. They asserted that many philosophical problems were indeed meaningless. Hence, they decided to abandon the traditional approach to philosophy and attempted to persuade people to utilise their approach instead. One of the chief tenets of logical positivism was that the supposed propositions of metaphysics, ethics and epistemology were not verifiable and so were not strictly ‘meaningful’.[1] Furthermore, Carnap, of the Vienna Circle, corroborated this view in his work â€Å"The Unity of Science†, when he stated that ‘we give no answer to philosophical questions and instead reject all philosophical questions, whether Metaphysics, Ethics or Epistemology’ (qtd. in the Stanford Encyclopedia of P hilosophy). Therefore, the purpose of the logical positivists was not to renovate the principles of traditional philosophy but to destroy them. Metaphysics was rejected on the grounds that its assertions were meaningless since they could not be verified in experience. Thus, statements about the existence of God were discarded as pointless because they could not be verified. Notably, whereas earlier critics of metaphysics such as Kant and Hume had rejected the claims of metaphysics as a form of theoretical knowledge, the logical positivists took over from Wittgenstein’s â€Å"Tractatus† the rejection of metaphysics as meaningless. Furthermore, the logical positivists argued that the propositions of metaphysics were neither true nor false but could be regarded as pseudo-statements (Logical Positivism 61). Metaphysics was not the only traditional discipline that the logical positivists were concerned about. Likewise, epistemology faced harsh criticisms from them. On one hand, the neo-Kantians saw epistemology as ‘the propaedeutic to metaphysics and all other philosophical disciplines’ (Oxford Companion to Philosophy 647). They maintained that philosophy could be reduced to epistemology in which a topic like â€Å"the reality of the external world† was discussed. On the other hand, for the logical positivists, epistemology was disregarded as a significant branch of philosophy because they thought that there was no way of verifying the assertions postulated by epistemology. They argued that this branch of philosophy was â€Å"quite meaningless like assertions about the Absolute.†[2] They held this position because for them there was no way of empirically verifying that an external world exists which is independent of the world we know now, as such those statements were ignored. Another tenet of traditional philosophy that the logical positivists disagreed with was ethics. Certainly, they all rejected any variety of transcendental ethics and any attempt to set up a â€Å"realm of values† over and above the world of experience. Passmore stated that, Assertions about values thus conceived, fall within the general province of transcendental metaphysics and had therefore been rejected as nonsensical. But while Schlick sought to free ethics from its metaphysical elements by converting it into a naturalistic theory along quasi-utilitarian lines, Carnap and Ayer argued that what are ordinarily taken to be ethical assertions are not assertions at all. For example to say that â€Å"stealing is wrong,† is neither, they suggested, to make an empirical statement about stealing nor to relate stealing to some transcendental realm. â€Å"Stealing is wrong† would either express our feelings about stealing, our feelings of disapproval, or, alternatively (this was where the logical positivist opinions differed), it is an attempt to dissuade others from stealing. In either case, â€Å"stealing is wrong† conveys no information. (par. 17) In addition to the above mentioned concepts, logical positivists also posited the idea that propositions of logic and mathematics were meaningful but their truth was discovered, not by experiment or observation, but by analysis. Also, for logical positivism the ‘business’ of philosophy was not to engage in metaphysics or other attempted assertions about what is the case but rather to engage in analysis. Furthermore, the only genuine propositions were those that are verifiable (Brown et al 218). Basically, the logical positivists’ emphasis was on logic and language. Logical positivists preferred that, instead of accepting traditional philosophy, philosophers should subscribe to the doctrine of verification. Doctrine of Verification Central to the movement’s doctrines was the principle of verifiability, often called the verification principle that is â€Å"the notion that individual sentences gain their meaning by some specification of the actual steps we take for determining their truth or falsity†.[3] According to logical positivism, there are only two sources of knowledge: logical reasoning and empirical experience. The former is analytic a priori, while the latter is synthetic a posteriori; hence synthetic a priori knowledge does not exist (Murzi 7). For logical positivists, the meaning of a statement lies in the method of its verification. This means that a statement has meaning if, and only if, it is verifiable† (Bochenski, 57). Verifiable, in this sense, means that the statement is derived from knowing the conditions under which it is true or false. If the statement cannot be proven true or false it is disregarded as meaningless. Carnap emphasized in â€Å"Logical Positivism† that only meaningful sentences were divisible into (theoretically) fruitful and sterile, true and false propositions (61). In essence, a sequence of words is meaningless if it does not, within a specified language, constitute a statement. Ayer also defined, explained, and argued for the verification principle of logical positivism. Ayer expressed, in his book Logical Positivism, the view that â€Å"sentences (statements or propositions) are meaningful if they can be assessed either by an appeal directly or indirectly to some fundamental form of sense-experience or by an appeal to the meaning of a word and the grammatical structure that constitute them. In the former case, sentences are said to be synthetically true or false; in the latter, analytically true or false.† Once the sentences under examination fail to meet the verifiability test, they are labelled meaningless. Therefore statements about metaphysical, religious, aesthetic, and ethical claims are considered insignificant. For the logical positivists, based on the verification principle, an ethical claim would have meaning only in so far as it professed something empirical. For example, â€Å"if part of what is meant by ‘X is good’ is roughly ‘I like it,’ then ‘X is good’ is false.† The primary ‘meaning’ of such sentences is emotive or evocative. Thus, for Ayer, ‘X is good’ is a meaningless utterance. As such statements are not verified by looking at the entire words in a sentence but by minutely analyzing the words singularly in a sentence to determine there meaning. Likewise, for Carnap, words or sentences must be verified by certain criterion, for instance, the syntax of a word must be fixed, that is in each use of the word in what Carnap calls an ‘elementary sentence’ the meaning must be unchanging. Secondly, for an elementary sentence containing a word, it must be determined from what sentence is the word deducible, and what sentences are deducible from the word. Also, under what conditions should the word or sentence be considered to be true or false, how is it to be verified and what is its meaning? For instance, take this example by Carnap using the word ‘anthropods’. Anthropods are animals with segmented bodies and jointed legs (this is the elementary sentence) from this it can de deduced that X is an animal, X has a segmented body, X has jointed legs. Hence, â€Å"by means of these stipulations about deducibility or truth- condition, about the method of its meaning of the elementary sentence about anthropod, the meaning of the word is fixed.† In this way every word of the language is reduced to other words and finally to the words which occur in the so-called â€Å"observation sentences† or â€Å"protocol sentences.† Carnap claims that it is through this reduction the word acquires meaning. (Logical Positivism 62-63). Problems with Logical Positivism In the Contemporary European Philosophy, Bochenski claimed that the doctrine used by logical positivists to verify sentences involved great difficulties of various kinds. For instance, a one protocol-sentence can be called into question and tested by another protocol-sentence, such as; the sanity of a physicist can be called into question and examined by the psychiatrist (58). The question has been asked of the logical positivist as to the basis of the protocol sentence, but they replied by stating that the object of experience can only be sensations. Questions of reality are ‘pseudo-problems,’ because we can never encounter anything but sensations and we can never verify the existence of things that are other than our sensations (59). Bochenski also commented that since verifications are made by the senses, â€Å"no statement can be verified other than those relating to the body and its movements; all statements of introspective psychology and classical philosophy are unverifiable, therefore meaningless.†[4] It follows that the only meaningful language is that of physics, and that all science should be unified. One condition remains to be fulfilled according to Bochenski and that is, for a statement to have meaning: it must be built in accordance with the syntactical rules of language. Therefore, it is meaningful to say, â€Å"the horse eats† but â€Å"the eat eats† has no meaning. Also statements that you and I know such as, ‘I love you Mummy’ or ‘I am feeling really sad today’ would have no meaning because they cannot be empirically verified. How then would we express our sensations? There is therefore no guarantee that things verified will remain verified; for example, it was commonly known that the world was flat and that if you go to the end you will fall off, this was how it was known to be until it was rediscovered by Columbus and his men that the world was round. Another problem outlined by Passmore is that, because â€Å"the meaning of a proposition is the method of its verification,† it is not a scientific proposition. Positivists responded to this by claiming that it should not be read as a statement but as a proposal, that is, a recommendation that propositions should not be accepted as meaningless unless they are verifiable. In response to Passmore’s statement, Carnap suggested that the verifiability principle is a clarification which will distinguish forms of activity which are otherwise likely to be confused with one another; metaphysicians will thus be able to tell what propositions are meaningless (Logical Positivism). Impact on Subsequent Philosophy Passmore wrote that logical positivism is dead, or as dead as a philosophical movement ever becomes; but it has left a legacy behind. Logical positivism was essential to the development of early analytic philosophy. It was disseminated throughout the European continent and, later, in American universities by the members of the Vienna Circle. According to the Routeledge Encyclopedia of Philosophy, this transplanted to the English – speaking world of ‘analytic’ philosophy. Originally, it set up a series of sharp contrasts: between metaphysics and science, logical and factual truths, the verifiable and the non-verifiable, the corrigible and the incorrigible, what can be shown and what can be said, facts and theories. Logical positivism tremendously influenced the philosophy of science and the application of logic (language) and mathematical techniques to philosophical problems more generally. Logical positivism therefore has an established place in the history and continuing development of philosophy. At least three reasons can be given for this. One is purely historical, regarding the considerable impact and influence of the movement in its glory days. A second lies in the intrinsic interest of its ideas. The third lies in the fact that even if no one today would call themselves a logical positivist some of its main positions, such as verification and emotivism in Ethics, are specification of the actual steps we take for determining their truth or falsity (Hanfling). Also, logical positivism was immensely influential in the philosophy of language. The philosophy of language for the logical positivists is concerned with four central problems: the nature of meaning, language use, language cognition, and the relationship between language and reality. Also, it was used in conjunction with logic (Wikipedia Encyclopedia par 1). The spread of logical positivism in the USA occurred throughout the 1930s. The pragmatic tradition of Pierce, James and Dewey, with its instrumentalist conception of science, provided a healthy stock on which to graft logical empiricism, which, particularly in Carnap’s work, already had a pragmatist bent (Hackers 183). The rise of logical positivism was evident in the European continent. The English philosopher Alfred Jules Ayer played an important role in spreading logical positivism. In his book, Language, Truth and Logic, Ayer completely accepted both the Verifiability Principle and the distinction between analytic and synthetic statements, and so he asserted that metaphysical sentences were meaningless. Furthermore, a direct influence was exerted by Waismann and Neurath who immigrated to England. According to Murzi, in his work â€Å"The Philosophy of Logical Positivism†, in the twentieth century, logical positivism has provided a platform for Italian philosophy, Polish philosophy and Scandinavian philosophy (19). The influence of logical positivism began to diminish around 1960 with the rise of â€Å"pragmatic form of naturalism due to Quine and a historical-sociological approach to philosophy of science due mainly to Thomas Kuhn.† Nevertheless, it must be noted that logical positivism played a very important role in the development of contemporary philosophy, not only for its philosophical principles, but also for its editorial and organizational activities. The efforts of the logical positivists to rid science and meaningful discourse generally, of metaphysics, their attempt to create a ‘unified science’ by laying bare the logical structure of scientific theories and thereby showing the structural similarities, their insistence on logic and empiricism as being the only two reliable and acceptable pillars of knowledge—all these contributed towards a scientific universalism.[5] Logical positivism is studied by many modern day students of philosophy and authors; philosophers well as have written about it thus testifying to its continued existence, if not its practice. Notwithstanding the above mentioned, it is necessary to note that while logical positivism may have laid a platform for other philosophies, its approach seek to have dismissed the traditional philosophies. Now, if one should pursue logical positivism seriously, then as postulated before, certain feelings would become empty. As Coppleston noted, the growth of logical positivism has helped to produce a mental outlook which was unfavourable to metaphysics and to religion (32). Logical positivism is synonymous to an amoral type philosophy and with those tendencies entrenched in our society a chaotic environment would be established. Personally, looking at its attempt to rid itself of things that can not be proven, in every case it has destroyed too much even where philosophers found it difficult to continue writing. Magee in his book, Confession of a Philosopher: A Personal Journey Through Western Philosophy from Plato to Popper, professed to this. For him, â€Å"there was a period in which several of the cleverest philosophers became reluctant to say anything at all, because almost nothing that might be deemed to be worth saying was, unless it was factually provable, permissible.† In conclusion, logical positivism, then, is an approach to verifying the meaning of statements through empirical observation. It is a philosophic tradition that attempted to use science and logic to determine the truth or falsity of statements, and to disprove the meaningfulness of metaphysical, ethical and epistemological ideas as we know them to be meaningful. Like any other school of thoughts in philosophy it has come up against criticisms, however it did make contributions to philosophy and philosophical thinking as we know it today whether it is by being studied, opposed, or supported by philosophers. Works Cited Ayer, A.J. ed .Logical Positivism. New York: Free Press Co-operation, 1959. Bochenski, I.M. Contemporary European Philosophy. London: Cambridge University, 1956. Brown Stuart et al. One Hundred Twentieth Century Philosophers. London: Routledge Publishing Ltd. 1999. Hackers, PMS. Wittgenstein’s Place in Twentieth Century Analytic Philosophy. London: Blackwell Publishers, 1996. Hanfling, Oswald. Logical Positivism. Oxford: B. Blackwell, 1981. Honderich, Ted, ed. The Oxford Companion to Philosophy. Oxford: Oxford UP, 2005. â€Å"Logical Positivism.† Concise Routeledge Encyclopedia of Philosophy. 2000. . â€Å"Logical Positivism.† Wikipedia Encyclopedia. 5 Nov. 2006 Retrieved 18 Oct. 2007. http://en.wikipedia.org/wiki/Logical_positivism Magee, Bryan. Confession of a Philosopher: A Personal Journey through Western Philosophy from Plato to Popper. New York: Random House Inc. 1997. Murzi, Mauro. The Philosophy of Logical Positivism†. Online posting. 18 Oct. 2007. http://www.murzim.net/LP/LP00.html Passmore, J. â€Å"Logical Positivism.† The Encyclopedia of Philosophy. 26 Oct. 2004 Retrieved 24 Oct. 2007. http://www.comnet.ca/~pballan/logicalpos(passmore).htm Runes, Dagobert. Living Schools of Philosophy: Twentieth Century Philosophy. Iowa: Littlefield, Adams and Co. 1958. Shah, Mohd Hazim. â€Å"Logical Positivism, Scientism, Universalism and Globalization.† Online posting. 11 Jun. 2002. 24 Oct. 2007. http://sts.um.edu.my/E-Library/Lecture%20Notes/SFGS6111/LP2.pdf â€Å"Vienna Circle.† Stanford Encyclopedia of Philosophy. 28 Jun. 2006 Retrieved 18 Oct. 2007 http://plato.stanford.edu/entries/vienna-circle/ ———————– [1] Honderich, Ted, ed. The Oxford Companion to Philosophy. Oxford: Oxford UP, 2005. [2] Passmore, J. â€Å"Logical Positivism.† The Encyclopedia of Philosophy. 26 Oct. 2004 Retrieved 24 Oct. 2007. http://www.comnet.ca/~pballan/logicalpos(passmore).htm [3] Honderich, Ted, ed. The Oxford Companion to Philosophy. Oxford: Oxford UP, 2005. [4] Bochenski, I.M. Contemporary European Philosophy. London: Cambridge University, 1956. [5] Shah, Mohd Hazim. â€Å"Logical Positvism, Scientism, Universalism and Globalisation.† Online posting. 11 Jun. 2002. 24 Oct. 2007.