Friday, September 20, 2019
Two Step Extraction Of Pyrethrins From Pyrethrum
Two Step Extraction Of Pyrethrins From Pyrethrum The experimental determination of the concentration and yield of pyrethrins from chrysanthemum pyrethrum flower is usually carried out with chromatographic techniques; and accordingly, a lot of methods have been developed over the years [Wang et.al, (1997)]. These include high performance liquid chromatography (HPLC) [Todd et.al, (2003); Essig and Zhao, (2001b)], gas chromatography (GC) [Essig and Zhao, (2001a)] and supercritical fluid chromatography (SFC) [Wenclawiak and Otterbach, (1999)]. GC was chosen for convenience in this study. The first-step involves using n-hexane as solvent to extract the pyrethrins from the solid sample (grounded and unsieved with particles size of about 30 meshes), and then the second-step, a purification step involves the use of supercritical carbon dioxide as solvent to obtain the pyrethrins from the crude hexane extract (CHE). The hexane extractions (100g sample size), in a water bath at controlled temperatures and vigorous stirring, generated pyrethr ins concentrations varying from 69.85 95.50mg/ml and yields of 0.85 3.76% of the dry weight. Extraction efficiencies under several conditions were investigated and the optimum extraction condition was 400C in 4hrs. Compared with the product from the factory, several undesirable components exist in the CHE. The SFE was carried out with a self built unit (extraction vessel of 120ml) with a sample size of 40ml of CHE. Concentrations of 57.25 93.79mg/ml and yields (after the second extraction) of 0.99 2.15% were obtained; with the optimum condition being 350C at a pressure of 20MPa in 2hrs. Compared with the product from the factory, this sample contains two extra components (Tricosane and Tetracosane) also used in insect control. Key words: Solvent extraction; supercritical carbon dioxide; pyrethrins; two-step extraction; crude pyrethrins extract Introduction Pyrethrum flowers are from the Chrysanthemum genus and are known commercially as painted daisies, painted ladies, buhach, chrysanthemum cinerariaefolium, ofirmotox, insect powder, Dalmatian insect flowers, or parexan. It is believed to be recorded first in Dalmatia [Visiani, (1842-1852)]. However, others contend that its insecticidal activity was first proven by Antun Drobac (1810-1882) [Bakaric, (2005)]. Yet there are claims that it was first identified as having insecticidal properties around 1800 in Asia [Jeanne, (2009)]; and that the Crushed and powdered plants were used as insecticides by the Chinese as early as 1000 BC [Amrith, (2004)]. The flower contains about 1-2% pyrethrins by dry weight, but approximately 94% of the total yield is concentrated in the seeds [Casida and Quistad, (1995)]. The chemical structure of the active ingredients, pyrethrins I and pyrethrins II was identified in 1924 [Chandler, (1948); Coomber, (1948)]. Kenya is the worlds main producer today with more than 70% of the global supply [Jones, (1973)]. The natural active ingredients are referred to as Pyrethrins; consisting of cinerin I, jasmolin I, pyrethrin I, cinerin II, jasmolin II and pyrethrin II. The first three (chrysanthemic acid esters) are referred to as pyrethrins I (PYI), and the rest (pyrethric acid esters) as pyrethrins II (PYII) [Essig and Zhao, (2001a)]. Pyrethrins, though insoluble in water, are soluble in many organic solvents [WHO, (1975)]. They are non-volatile at ambient temperatures; non-toxic to mammals and other worm-blooded animals; highly unstable in light (photodegradable); biodegradable; but toxic to aquatic animals [Todd et.al, (2003); Chen and Casida, (1969); WHO, (1975)]. Their usage is mainly in biological crop protection; domestic insecticides [Gnadinger, (1936)]; and the formulations of synthetic pyrethroids [Todd et.al, (2003)]. Although pyrethrins are soluble in a number of organic solvents (benzene, hexane, petroleum ether, alcohol, acetone, meth anol, chlorinated hydrocarbons, etc) other considerations (practical, economic and environmental concerns) limit the usage. These considerations reduce the choices to just few. One of the qualities of Hexane in extracting pyrethrins is its ability to effectively dissolve the active ingredients minus contaminants. Another is that its removal from the concrete is achieved at lower temperatures; limiting degradation due to prolonged heating. Again, its low boiling point is a needed quality and it can be recycled, reducing the weight of the concrete. Above all, it is inexpensive, considered environmentally friendly, less toxic, non-corrosive, and non-reactive; traits which make it the dominant solvent adopted, especially for processing plant (biological) materials (products) which are often thermally labile, lipophilic, and non-volatile and are required to be kept and processed at around room temperatures. Carbon dioxide (CO2) has a critical temperature of 31oC which makes it particular ly an attractive medium for these kinds of tasks. Though other supercritical fluids (SCFs) show critical temperatures in this critical state and can be adapted as solvents, they are often difficult to handle and obtain in pure state, may be toxic, explosive or ecologically unsafe. Supercritical carbon dioxide (Sc-CO2) is by far, the most extensively used due to its non-toxic, inert and non-flammable nature. It is also natural, inexpensive, plentiful, non-toxic and inflammable and generally environmentally accepted [Schneider et.al, (1980)]. Its most important properties are enhanced density, viscosity, diffusivity, heat capacity and thermal conductivity. Higher densities contribute to greater dissolution of compounds while low viscosities enable easy penetration into samples and facilitation of flow of extracted (targeted) molecules from the source materials with fewer hindrances [Dunford et.al, (2003)]. Diffusivity offers easy and faster transport through samples; hence offers bett er extraction strengths; and dissolved ingredients are also easily separated from the supercritical solvent by drop in pressure [Fattori et.al, (1988)]. Sc-CO2, for the above and many reasons used as solvent in extraction saves both time and money while retaining overall extraction precision and accuracy with high purity and healthy products that are of excellent quality [Raventos et.al, (2002); Mohamed and Mansoori, (2002)]. Expectedly, a lot of research is now focused on the extractions of plant materials with supercritical carbon dioxide due primarily to the global growing solvent (organic) regulations and more importantly, the economic benefits (in terms of low operating temperatures; faster extractions and easier purifications, and of course better product quality). Stahl and Schutz [Stahl and Schutz, (1980)] extracted pyrethrins with CO2 and proposed that in the 20à °C to 40à à °C temperature range decomposition (usually associated with pyrethrins extraction) does not occu r. Sims patented in the US, an extraction of pyrethrins using liquid carbon dioxide [Sims, (1981)] and Wynn and others patented using Sc-CO2 [Wynn et al. (1995)]. Wenclawiak and coworkers compared extracts obtained with ultrasonic (USE) and Soxhlet extractions (SEX); with hexane and Sc-CO2 extractions (SCE) and reported that direct extraction with SCE gave better pyrethrins content [Wenclawiak et.al, (1995)]. 2. 0. Experimental 2.1. Materials and Chemicals Grounded chrysanthemum (light green with a characteristic smell) sample and two pyrethrum concretes (yellow) were obtained from Yunnan Juxiang Natural Plant Products Company in China. The pyrethrins content of the concretes was claimed to be 50.0% (29.50% PYI and 20.50% PYII) and 85.15% (46.33% PYI and 38.82% PYII). Six individual standard solutions (using standard addition method) were prepared (from the 85.15% PY concrete-higher content, less impurities) for standardization of the analytical method. Analytical grade hexane (97.0%) and Ethanol (99.7%) were purchased from Sinopharm Chemical Reagent Co. Ltd in China, and used directly without any pre-treatment. CO2 (99.0 %) gas was supplied by Xin Hongli Gas Company also in China. 2.2. Experiments Three different experiments were performed: To establish the standard/calibration curves for determining the components, To implement hexane extraction and determine the yield of total PY in the grounded sample, and To implement SFE and determine the yield of total PY in the CHE. 2.3. Establishing Standard Curves The GC (Agilent) conditions used for establishing the standard curves are as follows: split injector with 20:1 split ratio at 2500C; Nitrogen as carrier gas at 1.6mL/min à ¬Ã¢â¬Å¡ow rate; injection volume of 0.1 à µL; temperature program started at 1800C, kept for 11 minutes, heated at 100C/ min to 2000C, kept for 8 minutes, heated to 210 0C at 100C/min, kept for 18 minutes, then heated to 2450C at 30 0C/min, maintained for 4 minutes; FID detector; HP-5 Column, 30 mm 0.32 mm id., 0.25 à µm à ¬Ã lm thickness. This column was chosen because it gives the best resolution, identià ¬Ã cation and quantià ¬Ã cation for products containing OH and C=O [Rosana, (2003)]. 2g (85.15% concrete obtained from the company) of the extract was transferred into a 100mL flask containing 10mL ethanol, and then made up to the final volume of with ethanol and mixed well. Six aliquots (1mL, 2mL, 4mL, 8mL, 16mL and 32mL) of this solution were transferred into a 50mL flask each and diluted with et hanol again to the mark. We then calculated the concentrations of the PY in each aliquot, considering the percentage of each group (PYI and PYII) in the sample provided (Table A1 in the Appendix), injected (with a micro syringe) 0.1à µL of each solution into the GC after filtering (0.45-à ¼m membrane filter) and recorded the elution times and corresponding peak areas (Table A2); subsequently, established the standard curves to express the relationship between the areas produced by the GC and the concentrations (Figure 2). 2.4. Hexane Extraction We extracted pyrethrins (from 100g of grounded sample of particle size of about 30mesh) with hexane in a water bath (YUHUA, DF-101S) in batches at different temperatures (35oC, 40 oC, 45 oC, 50 oC, 60 oC and 70 oC) and times (3hrs, 4hrs, 5hrs, 6hrs and 7hrs) in a 1000mL round-bottom flask, installed with a condenser. Agitation was achieved by stirring vigorously with three big size magnetic stirrers at a speed of 20rpm. The hexane was then removed from the pyrethrin concrete with a rotary evapourator (YUHUA, RE-2000B) at a temperature of 35 oC at a speed of 185rpm to obtain concentrated Crude Hexane Extract (CHE). Each concentrated sample was thereafter, filtered (0.45à µm) and 0.1à µL analyzed (Tables A3). This method has the advantage that the solvent is repeatedly recycled and temperature can be controlled. It offers a light coloured product with high recovery rate of pyrethrins; however, not only the desired components are extracted (Figure 3). Other soluble and hydrophobic sub stances (waxes and pigments) are also extracted [Kiriamiti et al, (2003)]. The solvent is removed by vacuum at lower temperature and the waxy thick mass left is the concrete; composed of essential oils and other oil soluble (lipophilic) materials. 3.0. Results and Discussion 3.1. Extract The extracts (CHE) contain pigments, fixed oils and waxes whose colour is deep yellow with characteristic smell. It also contains several undesired components (Figure 3) compared with the pure sample from the factory (Figure 1). 3.2. Effect of Extraction Temperature Temperature has long been reported to be a crucial factor in the extraction of natural pyrethrins [Atkinson et.al, (2004)]. Pyrethrins are sensitive to temperature (thermo labile) and are therefore, unanimously reported to degrade above 40oC [Stahl and Schuzt, (1980); Gourdon and Romdhane, (2002); Wynn et al, (1994)]. We investigated the effect of different extraction temperatures (40oC, 50oC, 60oC and 70oC) in fixed extraction times (5 hr gave better results than 6hr and 7hr). Our results conform to the reports (refer to Figure 4 and Table A3); the best yield (1.42) and PYI: PYII ratio (4.75) is at 40oC (but the best PYII yield-0.33 is at 70oC). This suggests that targeted components are extracted effectively at this temperature (40oC), above which two problems occur (separately or simultaneously): one is the extraction of more undesirable components at the expense of pyrethrins and the other is the decomposition of pyrethrins to form iso-pyrethrins [Stahl and Schuzt, (1980); Stahl, (1998); Gourdon and Romdhane, (2002); Wynn et.al, (1994)] thereby reducing the yield as seen. 3.3. Effect of Stirring We compared the effect of two stirring methods on extraction yield: the first with one magnetic stirrer and the second with three magnetic stirrers. The results are shown in Table A4, confirming that stirring improves extraction yield by facilitating the dissolution of the active ingredients and the effective distribution of heat. The extractions (at 40oC in 5hr) were repeated severally to ensure reproducibility and accuracy. 3.4. Effect of Extraction Time We further investigated the effect of extraction time by fixing the extraction temperature at 40oC with three magnetic stirrers; to establish the optimum extraction time (our initial time parameters were 5hr, 6hr and 7hr in which 5hr was the best). From Figure 5, the extraction yield increases steadily from 3hr to a peak at 4hr (see data in Table A5). Within this range, more desired components are extracted but after 4hr the yield decreases indicating that with prolonged time, even at the safest extraction temperature (40oC), less and less desired components are extracted and/or they decompose resulting in the decrease in yield. The drop in yield is consistent from 4hr (3.76%) to 6hr (2.15%). This implies that the optimum time (within the times investigated) is not 5hr as initially expected but rather 4hr. However, the ratio of PYI: PYII is best in 6hr (5.14). From 3hr to 4hr, the yield for both PYI and PYII appreciated but the increment in PYI (0.74) is greater than that of PYII (0. 38) hence the drop in the ratio. Between 4hr and 5hr, there is decrease in both PYI and PYII yields. Again, the decrease in PYI (0.98) is greater than that of PYII (0.49) accounting for the drop in ratio. The same reason accounts for the drop in ratio from 5hr to 6hr. 3.5. Effect of Concentrating CHE The effect of concentrating the CHE, on both PYI and PYII yield was analyzed (Table A6). Even though the concentrating temperature (35oC) was below the temperature above which PY degrades (40oC), there was loss in PY yield indicating degradation. This in our view may be due to the exposure of the pyrethrins directly to heat. As more hexane is evapourated, pyrethrins which hitherto, were locked in the solid sample matrix; surrounded by hexane and as such shielded from direct heat, is now in direct contact with the heat; and since they are sensitive to heat, decomposition is inevitable. However, the decomposition is small and negligible (about 2.25mg/ml which is about 0.41% of the total yield) due to perhaps the short concentrating time (about 30 min). 4.0. Supercritical Fluid Extraction (SFE) The CHE is too thick (viscous) to be used directly, coupled with the presents of undesirable components (waxes and pigments). A further treatment, usually with another solvent that only dissolve the desired compounds from the concrete is necessary. Different from other works, this study carried out SFE on the CHE as a purification step. We looked at the effect of time (hr), temperature (0C) and pressure (MPa) on extraction quality and yield. We have not studied the effect of particle size and pre-treatment; for information on this area, see the works of Kiriamiti and others [Kiriamiti et al, (2002)]. 4.1. Sample We concentrated the CHE in a rotary evapourator (from 500ml to 40ml at 185rpm in 30 minutes) for the SFE. 4.2. Extraction Process At the beginning of the extraction (Figure 6), all the check valves are closed except valve #2. This allows the CO2 gas into the compressor #4 (OLSB by Zheng Zhou Co. LTD, China) to be compressed, and the pressure gauges are allowed to attain equilibrium at a set pressure (10, 15 and 20 MPa). Valve #5 is then opened and the compressed fluid (Sc-CO2) is fed into the bottom of the extraction vessel #7 (120ml capacity) for up flow extraction configuration, containing the CHE (40ml) and metal fillings to facilitate effective contacting (increase internal mass transfer); which had earlier been heated to a set temperature (350C, 370C and 390C) and allowed to attain constant temperature with the help of the water bath #6. An appreciable time is allowed (5-10mins) for the total and complete dissolution of the crude extract and then valve #8 is opened and maintained until the pressure is in equilibrium again. The pressure reducing valve #9 is opened finally to collect the pyrethrins in the fl ask #10. A mass flow meter helps to determine the flow rate (1.5L/min). The extraction process is run and stopped at set times (1hr, 2hr and 3hr) and the extracts analyzed with the results tabulated (Table A8). The Metal fillings after each run were washed (10ml or 5ml of Hexane) and collected as residues to check for complete extraction. 5.0. Results and Discussion 5.1. Extracts The extracts did not contain visible pigments as was seen in the CHE. The colour was also different; light yellow to orange but the smell was similar. It also contained two extra components (Figure 10) which was found (by GC mass spectrometry) to be Tricosane (Peak 6) and Tetracosane (Peak 7). This was as a result of comparison with the pure sample from the factory (Figure 1). We compared the yield of the extracts after solvent extraction, concentrating the CHE and the SFE and noted that there was difference. The yield from the SFE was less due possibly, to the relatively high pressures used. Separation of the Sc-CO2 and the product is achieved by a drop in pressure. These high pressures have the tendency of causing the products to remain in the BPR or along the pipe (between the BPR and the flask in Figure 6) due to clotting as a result of the pressure drop; in spite of our use of heating tapes to minimize this effect. This is confirmed by the value of the yield in the residue (0.05%) which is far less compared to the difference between the concentrated sample yield (3.30%) and that of the SFE (2.15%, see Table A10). 5.2. Effect of Pressure According to Kiriamiti and others, the quantity of pyrethrins extracted decreases with decreasing pressure due to (i) the effect of density on the solubility of pyrethrins, (ii) the slightly high density of CO2, (iii) the moderate variation in density with pressure, and (iv) the very low undesirable extracted products [Kiriamiti et al, (2002)]. Our results conclusively conform to this (Table A7). The best extraction pressure was at 20MPa (at 350C and 2hrs). The concentration of PY also increases within this pressure range (from 81.34mg/ml 93.79mg/ml). Similar phenomenon was observed for both 1hr and 3hrs, indicating that more pyrethrins were extracted than the undesirable components within this pressure range (Figure 7). 5.3. Effect of Extraction Time The quantity of pyrethrins extracted decreases with extraction time at higher temperatures (above 400C), explaining that either pyrethrins decompose at these elevated temperatures or more undesirables are extracted instead. From Table A8, the yield and concentration of PY increase from 1hr to a maximum in 2hr (1.35% 2.15% and 90.42mg/ml 93.79mg/ml at 350C and 20MPa). Both however decrease in 3hr (1.24% and 82.30mg/ml, Figure 8). This implies that pyrethrins were extracted faster than the undesirables from 1 to 2hr but as the extraction proceeds, more undesirables were then extracted at the expense of the pyrethrins or which decompose. Therefore, prolonged extraction time rather favours the extraction of undesirables or promotes decomposition of pyrethrins. 5.4. Effect of Temperature Pyrethrins are thermo labile and therefore require being processed at low temperatures. Therefore, high extraction temperature does not only degrade the pyrethrins but also favours the extraction of undesirables (Figure 9). Within the temperature range we investigated, the best yield was at 350C (Table A9). 6. 0. Conclusions Pyrethrins are usually purified with organic solvents (ethanol, methanol, acetone, acetonitrile, petroleum ether etc) or their mixtures [Kasaj et.al, (1999); Henry et.al, (1999); Duan et.al, (2006)] which are generally expensive, flammable and explosive and above all, face strict legislative controls [Patrick, (2003)]. Alternatively, carbon dioxide is used to refining and purification. Sims proposed the use of liquid carbon dioxide [Sims, (1981)]. Similar to our method, Kiriamiti and others reported the extraction of pyrethrins from crude hexane extract (CHE) from batch extraction experiment using carbon dioxide [Kiriamiti et.al, (2003)] but with different extracting conditions and analysis method (HPLC). It is worth noting that our set up is very simple and less expensive coupled with the fact that our sample, after the SFE, contains two extra components (Tricosane and Tetracosane) not reported so far as part of the purification step. These components are not hazardous [Directive 67 /548/EEC] and have similar characteristics (may cause respiratory and digestive irritations), uses (as insecticides and biopesticides) and effects (they may not be detrimental to the insects but they certainly disrupt their behaviuor patterns and flushes them out for the more deadly pyrethrins I) as pyrethrins II [Chemcas.org; Chemnet.com; PPDB, (2011); Wylie, (1972); Lewis et.al, (1975)]. We developed a simple but efficient two-step procedure for the extraction of pyrethrins from chrysanthemum (pyrethrum flowers) and investigated the effect of various operating parameters on concentration and extraction yield. Based on the experimental results, we conclude that the two-step extraction of pyrethrins (first with hexane in a water bath and second with SC-CO2 as a purification step) is feasible and effective; the optimum extraction condition for high pyrethrins yield (3.76%) for the n-hexane extraction was 400C in 4hr; that vigorous stirring facilitated this; and that it is possible to achieve extraction yield of 3% or even more envisaged by Casida and Quistad. To our knowledge, this is the first time such a high recovery of pyrethrins is reported. A number of reasons may be attributed to this high recovery: i) extraction procedure, ii) choice of solvent, iii) vigorous stirring and above all, vi) the type of sample used. We further conclude that for the SFE (2.15% and 93.79mg/ml) the optimum conditions were 350C, at pressure of 20MPa in 2hr. 7.0. References Amrith S. Gunasekara, (2004): Environmental Fate of Pyrethrins, Environmental Monitoring Branch, Department of Pesticide Regulation, 1001 I Street, Sacramento, CA 95812 Atkinson B. L, Blackman A. J, and Faber H, (2004): The degradation of the natural pyrethrins in crop storage, J. Agric. Food Chem. 52, 280-28 Bakaric P, (2005): BuhaÃâà prirodni insekticid, Gospodarski list 17: 41-45 Casida J. E and Quistad G. B, (1995): Pyrethrum Flowers: Production, Chemistry, Toxicology, and Uses, Oxford University Press, New York Chandler S. E, (1948): The Origin and Early History of the Production of Pyrethrum in Kenya, Pyrethrum Post 1 (1): 10-13 Chen Y-L, and Casida J. E, (1969): Photodecomposition of Pyrethrin I, Allethrin, Phthalthrin, and Dimethrin, J. Agr. Food Chem. 17: 208-215 Coomber H. E, (1948): The Chemical Evaluation of Pyrethrum Flowers, Pyrethrum Post 1 (1): 16-19 Directive 67/548/EEC: The Dangerous Substances Directive (as amended) is one of the main European Union laws concerning chemical safety. Duan Wei, Zhengguo Li, Guomin Wang, Yingwu Yang, Yingguo Li and Yuxian Xia, (2006): Separation and purification of Natural pyrethrins by reversed phase high performance liquid chromatography, Chin. J. of Anal. Chem., vol.34, is.12, pp 1776-1779 Dunford N. T, Teel J. A and King J. W, (2003): A Continuous Counter Current Supercritical Fluid Deacidification Process for Phytosterol Ester Fortification in Rice Bran Oil, Food Research International 36, 175-181 Essig K and Zhao Z, (2001b): Method Development and Validation of a High-Performance Liquid Chromatographic Method for Pyrethrum Extract, J Chromatogr Sci 39 (4): 473-480 (8) Essig K and Zhao Z. J, (2001a): Preparation and characterization of a Pyrethrum extract standard. LC/GC 19(7): 722-730 Fattori M, Bulley N. 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Thursday, September 19, 2019
Slow Food Essay -- Nutrition
The trend of the Slow Food Movement has existed since the 1970ââ¬â¢s but has recently been thrusted into the fore front of prominent world issues as the cause and remedy of environmental challenges, local economic circumstances, and the complexities with social norms. The Slow Food Movement can be considered a counter-trend to Fast food. It was created in response to the augmentation of fast food a culture, the diminishment of people caring where the food comes from, and the diminishment of local food traditions. After a close examination of these factors, a prediction is made of the future trends of Slow Food Movement, and how the Slow Movement concept will evolve to become a part of everyday life. The Oxford American Dictionary defines trends as ââ¬Å"a general tendency or inclination, the general direction in which something tends to moveâ⬠(1999) A trend analysis is defined as an examination of a trend to identify its nature, causes, speed of development, and potential impacts (Cornish, 2001, p.78). Trends at times arise as a response to other trends. The same deduction can be made about food trends. For example when the Atkins diet was popular, retailers responded with low carbohydrate food options. In 2006, Burger King offered bunless burgers wrapped in lettuce, to appeal to the dieters embracing a low, or no carbohydrate lifestyle. Additional fast food restaurants including Arbys, Hardees, Carlââ¬â¢s Junior, and Subway followed suit with bunless options. While the trend of no or low carbohydrate diets have diminished the low carbohydrate options continue to be available upon request. The trend illustrates the affects trends have on each other. The Slow Food Movement has similar roots of establishment. The Slow Food Movement can be... ...ustry's Parade toward Low-Carb Menu Items. . Knight Ridder Tribune Business News 1(1), Retrieved Jun. 10, 2011, from from ProQuest Newsstand. (Document ID: 524271311). Schneider, S. (2008). Good, Clean, Fair: The Rhetoric of the Slow Food Movement. College English, 70 (4), pp. 384-402. Slow Food International. 1989. Slow Food Manifesto Retrieved from http://www.slowfood.com/international/2/our-philosophy "Trend n. & v." The Oxford American Dictionary of Current English. Oxford University Press, 1999. Oxford Reference Online. Oxford University Press. August 2011 US Department of Agriculture, Economic Research Service. 2008. U.S. Fertilizer Use and Price. Data set. Available atWeb site http://www.ers.usda.gov/Data/FertilizerUse/ (accessed 11 June 2011).
Wednesday, September 18, 2019
One Event Changed Everything Essay -- Personal Narrative Writing
One Event Changed Everything ââ¬Å"Our lives are not determined by what happens to us but by how we react to what happens, not by what life brings to us, but by the attitude we bring to life. A positive attitude causes a chain reaction of positive thoughts, events, and outcomes. It is a catalyst, a spark that creates extraordinary results.â⬠-Anon. After living in a place I loved for eleven years, I did not think that I would be able to have the same feelings or emotions towards another place. I thought everything I had was where I had been for years, but I was wrong. If you go into something new with a good attitude and know that there is always something else out there, then it works out for the best. Moving to Reno, Nevada from Glendale, Arizona defines me and is significant to my life because it made me grow as a person and it made me who I am today. In the middle of junior year, my parents told me that we were moving to Reno for my dadââ¬â¢s new job. I said, ââ¬Å"Okay, I will be living with Andri then, so I can graduate from Mountain Ridge?â⬠Boy was I wrong. I thought that since I only had a year and a half left of school before graduating that they would let me stay at my brother and sister-in-lawââ¬â¢s house so I could graduate with my friends. They had other plans for me. They decided that I should go with them so I could make new friends and start a new life, while keeping my friends from Arizona at the same time. So I went with it. I thought that maybe the change would be good for me. I also thought that I would have a chance at living my dream of becoming a high school cheerleader; something I did not get to pursue at my old high school because of the competition. So I went into the move with... ...great time anyway. After competition, the season was coming to an end. We had a couple of basketball games to go and then my dream would be over. The friends I met and the experiences I shared with them are never going to be forgotten. Graduation was next; a time when I would have to say goodbye to everyone that I had become close to. I had a blast the year and a half I spent in Reno. Like I said before, it was a life changing event that changed me for the better, made me the person I am today, and it defines me. I am a spirited, outgoing, athletic, strong, and a willing person. All of these characteristics I discovered about myself after moving away from the place and the friends I thought I would never be able to leave. There are millions of people and places out there, all you need to do is be willing to get out there and try something new.
Tuesday, September 17, 2019
Langston Hughes and the Civil Rights Movement Essay
During the early 1930s many black writers begin to produce works that helped to shape and define the Civil Rights movement. Among them was Langston Hughes whose poems and writing contributed directly to the rhetoric of the day and inspired many African-Americans, both in and out of the Civil Rights movement. Much of this grew out of what was called the Harlem Renaissance, which emerged during turbulent times for the world, the United States, and black Americans. World War I and the Bolshevik Revolution of 1917 had left the world in disorder and stimulated anti-colonial movements throughout the third world. In America, twenty years of progressive reform ended with the red scare, race riots, and isolationism throughout 1919 and led to conservative administrations through the twenties. While blacks were stunned by racial violence near the end of the decade and were frustrated by the lack of racial progress that progressivism had made, they were now armed with new civil rights organizati ons and confronted the approaching decade with new hope and determination. Education and employment opportunities had led to the development of a small black middle class, and few blacks thought that their future lay in the economically depressed rural South, resulting in hundreds of thousands migrating to seek prosperity and opportunity in the North. As these more educated and socially conscious blacks settled into New Yorkââ¬â¢s neighborhood of Harlem, it developed into the cultural and political center of black America. It is out of this environment that Langston Hughes developed. In 1926, professor Alain Locke (1969) observed, ââ¬Å"The younger generation is vibrant with a new psychology,â⬠which was shown by a shift from ââ¬Å"â⬠¦social disillusionment to race pride.â⬠Locke noted that this new psychology rejected the old stereotypes of black ââ¬Å"aunties, uncles, and mammiesâ⬠and substituted instead self-respect, self-dependence, and racial unity, and much of that is the core of Hughes writings. Emerging from social and inte llectual upheaval, the Hughes and the Harlem Renaissance marked a change in the attitude of blacks in the United States. While the Harlem Renaissance was not a political movement, its participants, including Hughes were affected by the political world around them and responded in varying ways to their political environment. Perhaps the most direct way that black writers addressed political issues was through political and protest writings, and Hughes made protest a significant element in his works, especially in his somewhat radical poetry of the early 1930ââ¬â¢s. In his poem ââ¬Å"Mulattoâ⬠, Hughes (1994) writes, ââ¬Å"Because I am the white manââ¬â¢s son, his own / Bearing his bastard birth-mark on my face, / I will dispute his title to the throne, / Forever fight him for my rightful place.â⬠Throughout his poetry, he directly and indirectly referred to vigorous hatred for the white man, of his peopleââ¬â¢s dreams deferred too long. He used literature to protest the inequality faced by blacks nationwide. Hughesââ¬â¢ writing put a level of anger into the early Civil Rights movement and he and other black writers felt that black literature could be used as a key weapon in the fight for civil rights. Hughes, though his writings also incorporated a little bit of communist philosophy in to the early Civil Rights movement, and Hughes wasnââ¬â¢t alone in his ideas. The Bolshevik Revolution of 1917 drew cheers from many black Americans who were thrilled to see a revolutionary organization pledged to racial and ethnic equality and proletariat brotherhood rise up and seize control. Seeing an opportunity to build a strong foundation on black Americans, the Communist Party of the United States pledged itself to encourage social interaction and intermarriage as a movement policy, and the organization proclaimed that African Americans had the right to self-determination in the South. Although the movement never really took hold or was able to sustain itself in America, Hughes and fellow black writer Claude McKay were angered by racial problems in the United States and enticed by the organizationââ¬â¢s pledge to uphold equality. Though never an official member of the Communist Party, H ughes, supported communism and defended the USSR through the 1940s. Hughes focused much of his effort into describing the life and experience of the black masses. He believed that social and racial problems were closely related to class conflicts, and that racial prejudice was only a manifestation of capitalism. In the early 1930s, a radical tone was pervasive in many of his works, especially in his volume of poetry entitled A New Song. One of the poems in the collection, for example, called for workers to rally in revolution with the words (1986): ââ¬Å"Better that my blood makes one with the blood / Of all the strugglingà workers of the world ââ¬â / Until the Red Armies of the International Proletariat / Their faces, black, white, olive, yellow, brown, / Unite to raise the blood-red flag that / Never will come down!â⬠Because of many his views, and his impact on the black community, the white society of America at the time of the Harlem Renaissance and even years after labeled him as a radical. Interestingly enough, Hughes with his lifelong commitment to racial integration was rejected by 1960s radicals who considered him to be a part of the problem, rather than part of the solution. While visiting the Soviet Union, Hughes acknowledged the problems the nation faced in letters written back to the United States, but also claimed that he had not seen any traces of segregation or racial prejudice. He then, for a time, began to share the view that literature needed to be viewed in terms of its potential political gain. According to Witz (1988) he wrote that, ââ¬Å"Writers who have the power to use words in terms of belief and action are responsible to that power.â⬠Hughes began to insist that writers have to demonstrate an awareness of the social and political realities with which they have to live and to take full advantage of the power and effect that their literature may have. Like McKay, he ultimately rejected Communism because of the absence of literary freedom that he observed. He proceeded to express publicly his disillusionment with communism and loyalty to the United States. Still, as with McKay, one must recognize that the political ideology of communi sm significantly impacted his works and ideas for a time and that those works and ideas impacted those involved in the Civil Rights movement who were taken up by his words. In the early 1940s Hughes also established a character in his short story writings named Jesse B. Semple. Through these short stories he used this character to represent the black man of his times. Hughes began writing the, ââ¬Å"Simpleâ⬠stories in 1943. It started as a weekly column in the Negro Newspaper, the Chicago Defender. During the 1940s there were many authors creating poems and stories to try and uplift the spirit of the black community in New York. However, Langston Hughes felt inspired to write about a fictional character, which in he attempted to represent all of the feelings of the black man without being blatant or bold. As Klotman (19)à wrote, ââ¬Å"Jesse B. Semple is certainly no romantic hero, protest victim or militant leader, no charismatic character for the young to emulateâ⬠yet his influence on the black community and their thoughts about civil rights could not be underestimated. He created Jesse B. Semple, a character that would make an effort t o represent the common man. His characteristics were that he had little formal education, but he had a lot of common sense and could see the truth in many situations. Langston Hughes used Semple and his stories to project the voice of all the black men of that time. Semple touched on issues such as racism, interracial marriages and any other important issues that showed what it meant to be black during that period. Hughes took every issue that he felt was necessary in the accurate representation of the Negro man, and projected through the life of Semple. The events Jesse B. Semple went through in his stories and his opinions and views of what was going on in the world showed a certain irony that the society of that time had for them. With the stories of Jesse B. Semple and his, ââ¬Å"simpleâ⬠life, he captured the mindset of every black man of the 1940s. Overall, that seems to be Hughesââ¬â¢ biggest influence, that he pictured the black America as black Americanââ¬â¢s saw themselves and then tried to install hope, and pride and a sense of entitlement into them. In poems such as ââ¬Å"I Tooâ⬠, Hughes dwells upon a theory that blacks had to be separate from others in society. He refers to himself as singing, America and then being America significantly referring to the end of segregation and discrimination. His use of creative imagery shows the kitchen as being a place of distinct yet individual strength. The author implies that by being separated from the rest of society he wasnââ¬â¢t of quality to be among the guests of the house, but never the less he demonstrates how being separate made him more of a stronger human being in accepting what others were, and putting aside the ignorance of others, which also demonstrated and ironic twist to the poem, as well as showing the reader that the speaker was ââ¬Å"Proud to be B lackâ⬠. In addition to those techniques use by the author, he also uses the structure of the poem to set up the reader and show them how the speaker was going from what he is now presently, and what he will accomplish to be in the future. In a nutshell, this is what the Civil Rights movement promised and the fact that Langston Hughes set it all down on paper at the veryà beginning, makes the influence undeniable. Bibliography Berry, Faith. Langston Hughes: Before and Beyond Harlem.Westport, Conn.: Lawrence Hill, 1983. Hughes, Langston ââ¬Å"A New Songâ⬠. International Working Order. New York: Viking Penguin, 1968. Hughes, Langston. The Best of Simple. New York: Hill and Wang, 1961 Hughes, Langston. ââ¬Å"Mulatto,â⬠The Portable Harlem Renaissance Reader, ed, David Levering Lewis. New York: Viking Penguin, 1994 Klotman, Phyllis R. ââ¬Å"Jesse B. Semple and the Narrative Art of Langston Hughes.â⬠Critical Essays on Langston Hughes. Boston, Mass.: G. K. Hall & Co., 1986 Locke, Alain. The New Negro, New York: Atheneum Press, 1969. Meltzer, Milton. Langston Hughes: A Biography. New York, NY: Thomas Y. Crowell Company, 1968 Mullen, Edward J. Critical Essays on Langston Hughes.Boston, Mass.: G. K. Hall, 1986. Wintz, Cary D, Black Culture and the Harlem Renaissance. Houston, Rice University Press, 1988
Monday, September 16, 2019
Higher Cost of Healthcare: Deterrent for Smokers Essay
This research is focused on the hypothesis that if an employer would require a higher healthcare cost for employees who smoke, would this prevent them from continuing the vice and quit smoking for good? Literature Review According to Andre, Velasquez & Mazur (2008) ââ¬Å"the American Medical Association recently revealed that at least 25 cents of every health care dollar is spent on the treatment of diseases or disabilities that result from potentially changeable behaviors. â⬠Smoking, by itself, costs the the U. S. health care system over $65 billion annually (par. 1). Meanwhile, in an article entitled ââ¬Å"Smokers Pay More for Health Benefits: Employers Ask Smokers to Pay Higher Health-Care Premiumsâ⬠written by Lisa Cornwell, she said that a number of companies have already imposed higher health care premiums to employees who smoke (par. 2). These companies, both private and public, resort to this measure to entice the smokers to quit smoking for good. Some companies impose $20 to $50 a month for these employees. According to the Medical Expenditure Panel Survey: ââ¬Å"Smoking is costing the economyâ⬠(cited in Cornwell,2006, par. 2 ). Significantly, the ââ¬Å"employers are charging smokers extra for health insurance in an effort to rein in costs. The estimated costs of medical expenses and lost productivity are about twice the cost of cigarettes per pack or moreâ⬠(cited in Cornwell,2006, par. 2 ). Additionally, in an interview by Helen Darling, president of the National Business Group on Health, she remarked that ââ¬Å"In addition to employers having to pay out more in health-care costs, public opinion is now solidly on the side of eliminating smoking, and workers are realizing increasingly that they are having to pay for othersââ¬â¢ lifestyle choicesâ⬠(cited in Cornwell, 2006, par. 0). National Business Group on Health is a non profit organization with more than 200 member employers. Despite the imposition of higher healthcare cost, some companies offer programs that will entice smokers to quit smoking. Once they sign up and complete the program, they are waived of a certain amount which is usually required for smoking employees. However if they resume the vice, the fee will be asked of them in the following year. Basing from the number of the employees that signed up for the program, it appears to be a motivating factor for smokers to finally give up on smoking. However, an issue cannot be without an opposing side. Lewis Maltby, president of the National Workrights Institute, remarked ââ¬Å"making smokers pay more for insurance for their health choices isnââ¬â¢t inherently wrong [but] do we really want to live in a world where employers penalize us for everything in our private lives that isnââ¬â¢t healthy? â⬠(cited in Cornwell, 2006, par. 10). Methodology This study is conducted through interview of sixty (60) respondents. The respondentsââ¬â¢ age ranged from 23 to 40 years of age. Among them were 22 females and 38 males. They were all smokers and of different histories. The range of their ages was 14 to 27 when they started smoking tobacco/cigarettes. The main questions asked from the respondents are as follows: (a) How many sticks of cigarettes do you smoke per day? (b) On average, how may times have you consulted with a medical doctor with sickness relating to your vice? (c) Are you willing to shoulder higher healthcare cost for smoking? (d) If you had no choice but to shoulder higher health care cost, would you quit smoking for good? Data Analysis and Resultsà Among the sixty (60) respondents, the cigarette packs consumed per day range from 3 sticks to 1 pack a day. A pack contains 20 sticks of cigarette. As regards medical conditions, 56% of the smokers admitted to have smoking-related illnesses such as cough and sinus infections. In a year, they visit the doctor 2 to 3 times for such sickness. When asked if they are willing to shoulder additional healthcare cost for their vice, 40% said yes, since they are willing to take responsibility for their own vice. However 60% said no. On the imposition of a higher health cost from their employers; and if this would make them quit smoking for good, 38. 3% said they would definitely quit smoking, 43. 3% said they would make an effort to quit smoking, 18. 3% said it would not make any difference in their smoking habits. Discussion Basing from the interviews, only 18% of the respondents are adamant to quitting smoking despite imposing higher costs for healthcare. Significantly, these respondents have been smoking for almost their lives and have not yet experienced any serious illness associated with their smoking habit. One of the respondents remarked that he is willing to shoulder a few more of his income and earnings since smoking, according to him, does him good that is worth his money. However, more significantly, 38% are willing to give up the vice and another 43% were willing to make an effort to quit for good. Basing from this research, it shows that higher health care cost can be an effective deterrent for smoking. One of those willing to give up smoking for good was a single woman who said she could instead use the money for clean fun than for smoking-related sicknesses. Conclusion and Recommendation Judging from the result of this study and various interviews of employers (as stated in Cornwellââ¬â¢s article), the additional expenses for health care for smoking apparently discourage smokers from pursuing the vice. Evidence shows that most are willing to undergo therapy and programs that will help eliminate the tobacco habit for good, as they are to shoulder the expense of consultation, treatment and medication for such voluntary health risk.
Sunday, September 15, 2019
Future Trends of Human Resource Essay
1. Introduction What does the human resource information system look like in the future? It is hard to find an accurate answer for me. Every year, thousands of HRIS specialists trying to predict the future trends of HRIS and, of course, their prediction differ. However, despite of what prediction they had made, I think social media will play an important role in next few years. In this paper, I will try to discuss what social media means to human resource and discuss three major players in the fieldââ¬âFacebook, LinkedIn and Twitter. 2. Social Network Site vs. HR According to the 2011 Kelly Services Global employees Index research, published by the famous human resource service organization Kelly Services, social network site is becoming the ââ¬Å"edge toolâ⬠in the future workplace. According to the research, social network site (SNS) is changing the way of life and work. It expanded its function from only entertaining to boosting working efficiency and enhancing the success rate of job applying. The research shows that over 80% of workforce is using SNS every day, while over 60% of workforce considers it as a work booster. According to the research, a lot of employees think they can develop an instant synchronized ââ¬Å"expert tankâ⬠, from which they can acquire relative knowledge, skill and experience, so that they will be support by experts wherever, whenever. They also regard SNS as a pipe cleaner of the networking. By using SNS, they can manage their networking just within few clicks. It is a cost efficiency and personalized way. In addition, they also use SNS to relieve work pressure. According to the research, SNS is now penetrating to the area of traditional recruiting. The advantage of it includes no limits of time and space, cost efficiency and high reliability. The research indicated that over 90% active job seekers are now using SNS at least once per week. It also indicated that job seekers who age below 25 are more willing to use SNS as a tool to find job, while who age over 35 are more possible to find a job by using it. The research suggests that company should pay attention to what SNS may change the future workplace. According to the research, the most common worries toward SNS are affecting productivity, occupying internet and threating the information security. It also report that there are a lot of companies are now start using SNS to recruit, manage market, promote public relation and guide career development by setting new policies and using latest antivirus technics. 3. Facebook Facebook is a SNS launched in February 2004, owned and operated by Facebook, Inc. By the time of October 2012, Facebook has over one billion active users, more than half of them using Facebook on a mobile device. According to the research, 23% of Facebook users check their account 5 times or more per day. By the time of May 2012, Facebook received more than 1.6 billion visits per week. There are over 1,000,000 links shared on Facebook every 20 minutes. If you regard Facebook merely as an entertaining SNS, you will be absolutely wrong. In the era of internet, Facebook is now developing different social platforms. It transforms its function from just connecting and entertaining people to job bank and social synergy. By Facebook recently launched job applying app ââ¬Å"Jobviteâ⬠, people can find, refer, and match jobs to friends with Jobviteââ¬â¢s proprietary matching technology, providing better access to opportunities for job seekers and more quality hires for employers. Users can connect and apply to jobs completely within Facebook; and they can see their status in the hiring process at any time, creating a positive, transparent relationship for companies and candidates. By using another job applying app ââ¬Å"jobandtalentâ⬠, users can discover and leverage their existing Facebook network to find job opportunities and stand out to top companies. Jobandtalent claimed that they are working with world top companies like Goldman Sachs, Deloitte and Google. The fact is that the data stored on Facebook not only including job relate area, but also including other areas, such as daily life. Employer can acquire 360-degree background information of candidates via Facebook. ââ¬Å"It is easy to track record of candidates on Facebook. These records may imply personal interests, personality and other attributesâ⬠Said an HR specialist, ââ¬Å"Traditional resumes are monotonous, like masks, but these records are alive and we can totally tell a difference.â⬠It is not surprisingly true. Tell me if I wrong, if the records of a candidate show that he use the ââ¬Å"fâ⬠word all the time, dare you or dare you not hire him? Job applicants like him will lose his opportunity from the beginning. Facebook is now challenging LinkedIn by this advantage. According to the survey conducted by Bureau of Labor Statistics, almost half of companies are now using Facebook in their recruitment process, such as Boeing and Dell. They use Facebook not only for job posting, but also for background investigation. However, research shows that there are different between social media behavior and real life behavior. It is to be studied whether it is reliable to investigate candidates via SNS. 4. LinkedIn LinkedIn is a SNS for professional people. Launched on May 5th, 2003, it is mainly used for professional networking. By the time of June 2012, LinkedIn reports more than 175,000,000 users in more than 200 countries. Monster is one of three largest job posting web site, however, its financial report showed a significant decline in business revenue. According to the market analyst, because of the blooming of LinkedIn, companies like Monster are losing market share in a large scale. Just like Facebook, LinkedIn founded upon the theory of Six Degrees of Separation. Also it was not designed for recruiting; LinkedIn became the major way to recruit in the U.S. by the time of 2006 and achieve profitability. LinkedIn is known as its high accurate matching rate. It can even ââ¬Å"pushâ⬠eligible candidates to employers by preset standard. According to the co-founder Reid Hoffman, it is more and more important for people to utilize their networking in the future. If you want to change you r job every two or three years, you have to maintain your networking to find new opportunities. SNS is the easiest way to do it. You donââ¬â¢t have to make call after call and desperate to find topic to cottoning up, you donââ¬â¢t have to visit people with gifts door after door. The only thing you have to do is just within few clicks, and you can make connection with people you want to. In his opinion, the value of LinkedIn is ââ¬Å"concentrate in the value momentâ⬠. Also Facebook has more user base and more stickiness; it is not safe to say that LinkedIn is losing the game. The orientation of these two web-sites is different. The business scope of Facebook is wide and the ââ¬Å"killer appâ⬠of it is social game and ââ¬Å"Shareâ⬠, while LinkedIn concentrate in professional occupations. In a way, the overlap of these two web-sites is small. People regard Facebook as ââ¬Å"individualâ⬠and LinkedIn as ââ¬Å"professionalâ⬠. Compare to strong interaction of Facebook, LinkedIn is not that strong. However, this weak interaction as ââ¬Å"professional communityâ⬠is where it value lies. For the user of LinkedIn, log in every day and post threats is meaningless and way far from the identity of professional, it will only imply that you are not in the working status. In other word, user stickiness makes little sense for LinkedIn. In addition, compared to Facebook, LinkedIn is a real-name, high quality user concentrated SNS. In other word, the user group is rich and high-educated middle-aged professions. This user group is known as high business value. According to the statistics from Quantcast, in the United States, the proportion of user over 35 is over 70%, the proportion of user with bachelor or above education is over 75% and the proportion of user with over $100,000 incomes is over 39%, compared to Facebook with only 32%, 53% and 32% (Chart 1). Chart1 Demographic Analysis of Facebook and LinkedIn Whatââ¬â¢s more, in business related area, LinkedIn is highly recognized than Facebook. According to a research conducted by Jobvite, in job applicants who are now using or will use SNS to find jobs, more than 95% indicate that they will choose LinkedIn. Only 59% chose Facebook and 42% chose Twitter. In people who already find a job by using SNS, 89% of them used LinkedIn, 28% used Facebook. To sum up, although Facebook is now challenging LinkedIn in professional SNS area, LinkedIn is still No.1 in the field. 5. Twitter Twitter is an online social networking service and micro blogging service that enables its users to send and read text-based messages of up to 140 characters, known as ââ¬Å"tweetsâ⬠. Launched in July, 2006, the service rapidly gained worldwide popularity. By the time of 2012, over 500,000,000 active users generating over 340,000,000 tweets per day and handling over 1,600,000,000 search queries per day. Twitter has been described as ââ¬Å"the SMS of the Internetâ⬠Unlike Facebook and LinkedIn, Twitter has its own characteristics. Firstly, there is a limit of characters for each tweet. You can only send up to 140 characters in one tweet. This limit made information fragmented. This kind of fragmented information eliminated the time of reading, and by this elimination user can spread their thought more accurately and more efficiency. Secondly, you donââ¬â¢t have to get ââ¬Å"approvalâ⬠to follow somebody. This character makes Twitter more like a broadcasting station. Users could follow the Twitter of their favorite celebrity, brand and company to acquire latest trend. Likewise, the later will use Twitter to improve public relation to the target user group. Thirdly, most of user write and read tweets by using mobile devices. That means you will get first hand news via Twitter. An interesting statistic shows that within Twitter, Facebook and LinkedIn, Twitter has second largest influence of commercial both in B2B and B2C. Facebook has the largest influence of B2C commercial while LinkedIn has the largest influence of B2B commercial (Chart 2). Chart 2 Influences in Commercial For human resource, Twitter has two major functions. The first function is to use Twitter to improve company image. More and more companies now hiring Twitter specialist to manage company Twitter. The other is to recruit. Compare to Facebook and LinkedIn, Twitter is more cost saving, speedy and simple. According to William Fisher, the founder of job searching web site TwitJobSearch, there are more than 340,000 jobs posting in Twitter per month. TwitJobSearch release two appsââ¬âJob-Deck and TweetDeck. Users can sort and find job posting related tweets by using these two apps. 6. Cites http://recruiting.jobvite.com/company/press-releases/2011/jobvite-launches-social-job-app-on-facebook-to-power-referral-hiring/ http://callcenterinfo.tmcnet.com/news/2011/10/03/5822750.htm
Negative Classroom Behaviors Essay
In the classroom there are many opportunities for disruptions to the flow of learning. When the process of education is disrupted it affects learning outcomes and student progress. Educators and students both play a vital role is how smoothly the class is run. In this paper we will examine common disruptions in the classroom and look at carious ways that these disruptions can be resolved productively and efficiently. Through incorporating different discipline and classroom management styles most interruptions to learning can be avoided and the process of education can continue. Disruptions come in many forms and we will look at a few. We will first look at common disruptions in the classroom caused by students and then take a look at those caused by teachers. Yes teachers can be a disruption to the learning process and as we will see sometimes they cause more disruption than their students. It seems that often in todayââ¬â¢s society when we think of the typical public school classroom, images of chaotic behavior, chattering students and paper being thrown quickly come to mind. This behavior, while not uncommon should not be the norm, there is a solution. The first three behaviors that we will address is the seemingly ever-present excessive talking, laughter and general outburst. It seems that no matter how many times the lights are turned off, names of students are written on the board, recess or free time taken away students continue to use their voices out of turn in excess ways, making instruction and learning difficult. Often times when students have an outburst in the class or the talking becomes excessive, teachers sometimes give a general knee-jerk reaction.à They may yell at the student who has been consistently talking to ââ¬Å"be quiet orâ⬠¦ then some threat of a punishment is given and the student is quiet for a moment and the behavior is likely to happen again and the process continues. Educator Barbara Coloroso believed that students should be taught how to govern themselves accordingly and that whatever actions took place in the classroom they were not only responsible for them but that they were held accountable for them. Barbara guided educators to understand that an important part of education students was to also teach them inner discipline and self control. (Building Classroom Discipline, 11th edition, 2014) In her book Kids Are Worth It: Giving Your Child the Gift of Inner Discipline, Coloroso outlines key ways in which not only parents but also educators can teach children how to have inner discipline. Coloroso suggest that inner discipline be developed as follows; First students must be shown what they have done wrong, then given ownership of the problem hence making them responsible, following this students are guided on ways to solve the problem when appropriate. Finally Coloroso encourages to educators to ensure that during this entire process the dignity of the student is kept in tact. I imagine that by incorporating this strategy into my classroom management and discipline style my students will gain more self-control and become more aware of the consequences behind their actions. In this way, they will be far more likely to think before they act. Likewise I as a teacher will feel better about the way in which I handle disruptions. With the ability to handle each disruption as a possible teaching moment that encourages students to do better, rather than simply pointing out what they did wrong, students will develop a better sense of trust. Likewise by ensuring that in each situation the student is treated with dignity, students are aware of the respect I have for them and this respect become reciprocal. Two other common disruptions in the classroom are that of students who get out of their seats at inappropriate times and who take a long time to get organized, settle down and get started on their work . This not only disrupts learning for the student who gets up but it causes a distraction for those around. Often there are tedious reasons for why students are not in their seats. When asked why have they gotten up, a student may respondà ââ¬Å"I was going to sharpen my pencil.â⬠Likewise when asked why have they not sat down and began the warm up they may reply ââ¬Å"I cannot find my pencil.â⬠Educators Harry and Rosemary Wong created a classroom management and discipline theory that creates a way to eliminate many classroom disruptions. The Wongââ¬â¢s theory suggest, that beginning with the first day of class, students be taught that not only the classroom but that the entire school was a place for successful learning. This theory had to be accepted school wide in order to work effectively. In order to achieve that success teachers, students and administrators and support staff, must do their part. The Wongââ¬â¢s suggest that the biggest hindrance to learning is not the behavior of the students but the ineffective manner in which teachers disseminate information regarding the roles, rules, procedures and expectations in the classroom. (Building Classroom Discipline, 11th edition, 2014) Upon introduction to the class, teachers are encouraged to two things. First teachers must go over the roles, expectations and responsibilities of both teacher and student (Building Classroom Discipline, 11th edition, 2014). This is done over a period of several days and may continue through reinforcement throughout the first portion of the school year. In this way students not only understand where they fit in the classroom but they also know how everyone else fits as well. In my own classroom I can visualize my students on their first day. Part of my classroom management style will be to ensure that there is a procedure set in place for most of the foreseeable situations in the classroom. One thing that I will make certain to do, is to make the procedures detailed yet simple to understand and follow. In this way my students will be clear on what to do and when. For example, the student who has wasted ten five minutes of the 15 minute warm up time, will know in the beginning of the school year that sitting down and getting started on the warm-up up within the first three minutes of class is mandatory. If you are not prepared and do not have all of your materials, there are always extras that can be checked out from me and then returned at the end of class. Simple procedures like this will eliminate small disruptions and keep the learning process flowing. The next two disruptions are those students who lack respect for teachers and fellowà classmates along with horseplay in the classroom. Teachers must establish and demand respect in the beginning of the class. Students must know not only what is expected of them, but also what happens when they fall short of those expectations. Educator Craig Seganti teaches teachers how to take charge in the classroom. Taking the Seganti approach in my class will dictate that my students know that I am the authority in the classroom. Establishing this authority by setting the rules along with the consequences of breaking them, and enforcing them from day one will put me in control from the outset. When students see that there is no wavering in the rules, they will take what you are saying seriously. Establishing that the classroom is a place of learning and that anything that disrupts that will have consequences will if not completely eliminate, will certainly minimize disruptions. When teachers and students are disrespected in the classroom it would be good to incorporate civility in the classroom. P.M. Forni was best known for teaching students how to behave civil and with respect n the classroom. By encouraging students to conduct themselves in a way that reflects the ââ¬Å"Golden Ruleâ⬠students will be far less likely to tease and disrespect their teacher and classmates. (Building Classroom Discipline, 11th edition, 2014). Using these two strategies in the classroom will be of great value in the way the classroom is managed. Finally I want to take a look at three behaviors that are exhibited by teachers that cause disruptions in the classroom and halt the learning process. Disorganization, nagging and the inability to leave whatever you have going on at home, at home can cause the classroom environment to feel unsafe and chaotic (Building Classroom Discipline, 11th edition, 2014). Using a combination of strategies from authorities on classroom management can help with these hindrances to education. First knowing what you want your classroom to look and feel like I a huge help in getting and staying organized. Often times teachers become disorganized because they have lost control of the classroom. By establishing your authority in the classroom as suggested by Seganti, you are less likely to lose control and if this does happen it should be easier to regain. Constant nagging of students over trivial matters of work habits or behavior are not helpful. In the long run you are not taken seriously. Students must know how to behave in the classroom. Ensuring as suggested by Wong that students are crystalà clear on expectations and procedures, teachers will spend much less time nagging and more time teaching. Lastly when teachers are unable to leave their home life separate from their classroom the results can disrupt and devastate a classroom. Teachers must before anything else, know their role. As a teacher you are there to provide a safe learning environment for your students. When your personal life interferes with that, learning outcomes and student-teacher relationships are compromised. In my classroom I imagine that by establishing an initial foundation of authority based on my acknowledgement of my role as teacher and educator, I will be able to create safe, fun and effective learning environment. By creating my classroom management style, revisiting it when necessary and setting up rules and procedures from day one, I will have the freedom to teach without disruptions and my students will be able to achieve all of the learning outcomes that have been set for them. Reference Page 1. C. M. Charles Building Classroom Discipline, Eleventh Edition, 2014
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