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 20 °C to 40  Ã‚ °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  ¬Ã¢â‚¬Å¡ow rate; injection volume of 0.1  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  µm  ¬Ã‚ lm thickness. This column was chosen because it gives the best resolution, identi ¬Ã‚ cation and quanti ¬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) 0.1 µL of each solution into the GC after filtering (0.45-ÃŽ 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 (0.45 µm) and 0.1 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): BuhaÄ  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. 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Global Warming and Human Population Essay

Forest loss is directly-associated with human population growth. In 1921 human population was 25. 13 crores and forests cover was 104. 05 million hectares. By 1989, forests cover reduced to 64. 01 m ha, while human population in 1991 reached to 84. 39 crores. Deforestation is due to diversion of forest land to agricultural land, river valley projects, roads, industiy and urbanization, transmission lines and activities like shifting cultivation, fuelwood and timber collection overgrazing fires and acid rains (vide Rana, 2006). Green wealth index (GWI) is an indicator of green wealth possessed by a State or Union Territory and Green Protection index (GP1) is a qualitative calculation of protection accorded examining forests cover, recorded forest area and protected area coverage. Andaman and Nicobar Islands are richest in their green wealth with GWI at 0. 747, while Sikkim for protecting its natural heritage ranks highest on GPI scale with 0. 903. All India GWI is a dismal 0. 193 (Ghosh, 2004). A total of 0. 397 m ha forests loss in Madhya Pradesh is recorded with tribal areas accounted for about 0. 219 m ha. And in Andhra Pradesh forest loss was about 0. 46 m ha in tribal areas. This trend continues in Northeast including Assam (State of the Forest report, 1999). Various ethnic groups practice various forms of agriculture as main stay of economy in NE region. Rice is major crop though maize and millets are grown. Traditional agricultural systems are Zabo, terrace construction and jhum or shifting cultivation. Zabo, an indigenous farming system of Nagaland combines agro-forestry and animal husbandry and is common to individually owned lands of about 2. 5 ha. For terrace construction, the area is cleaned by cutting and burning forest vegetation. Jhum cultivation is practiced roughly by 5 lakhs tribal families. A total land area of 4. 36 m ha is being affected by jhum cultivation, out of which 2. 7 m ha is in NE region. Jhum cycle has reduced to 4-5 years in Meghalaya, 5-10 years in Mizoram and Tripura, 6-15 years in Nagaland and Manipur and 5-10 years in Arunachal Pradesh. Such cultivation results in soil erosion and loss of soil fertility. In areas, where bamboos are cut and burnt, K- rich ash accumulates for jhum crop. This fallow land invites several weeds and it takes a very long time for soil, to support crop plant growth. Modern agriculture with longer cycles of 10 or more years and agro-forestry system are suggested for control of jhum (Sharma. 2004). Problems relating to use and conservation of natural resources in developing countries are qualitatively different than those of developed countries. In developed countries, the primary issue is protection of what remains in nature, but in India conservation of natural resources must necessarily consider the claims of human population on these resources for their sustenance and livelihood. Such population is dependent on forests and is among the poorest, as forests form life support systems for them. Any legal and administrative regime must aim to judiciously utilize these resources for addressing the concerns of livelihood while ensuring sustainability of their use (Hazra, 2002). Essay on Global Warming: Causes, Effects and Remedies Global warming is the greatest challenge facing our planet. It is, in fact, the increase in the temperature of the earth’s neon- surface air. It is one of the most current and widely discussed factors. It has far-reaching impact on biodiversity and climatic conditions of the planet. Several current trends clearly demonstrate that global warming is directly impacting on rising sea levels, the melting of ice caps and significant worldwide climate changes. In short, global warming represents a fundamental threat to all living things on earth. Global average temperature rose significantly during the past century. The prevailing scientific view is that most of the temperature increases since mid-20th century has been caused by increases in atmospheric greenhouse gas concentrations produced by human activity. Most scientists agree that planet’s temperature has risen 0. degree Celsius since 1900 and will continue to increase at an increasing rate. As a result, the world is getting warmer. The year 1990 was the hottest year in the last century. Together with 1991, the years of 1983, 1987, 1988 and 1989 have been measured to be the warmest six years in the last hundred years. The year 1991 was the second warmest year of the past century. The consequences of the rise in temperature is being felt all over the globe the findings of scientific research done in this field reveal that the temperature of the earth is likely to rise from 1. 4 °C to 5.  °C within a period of 100 years. Unfortunately, the imbalance which we have created between our life and earth is already showing the signs disasters in the form of flood, cyclones, landslides, tsunami, drought, etc. If the imbalance continues to rise, one day this will pose a question mark on the existence of this planet. Carbon dioxide (C02) which is an important constituent of environment is causing a warming effect on the earth’s surface. It increases the evaporation of water into the atmosphere. Since water vapour itself is a greenhouse gas, this causes still more warming. The warming causes more water vapour to be evaporated. The C02 level is expected to rise in future due to ongoing burning of fossil fuels and landuse change. The rate of rise will depend largely on uncertain economic, sociological, technological and natural developments. Other gases such as methane, CFCs, nitrous oxide, tropospheric ozone are also responsible for global warming. Increases in all these gases are due to explosive population growth, increased industrial expansion, technological advancement, deforestation and growing urbanization, etc. Trees play a significant role in the global carbon cycle. They are the largest land-based mechanism for removing carbon dioxide from the air. Deforestation is checking these positive processes. It is the second principle cause of atmospheric carbon dioxide. Deforestation is responsible for 25 per cent of all carbon emissions entering the atmosphere, by the burning and cutting of 34 million acres of trees each year. Everyday over 5500 acres of rainforest are destroyed. As a consequence of massive loss of forests, global CO, levels rise approximately 0. 4 per cent each year, the levels not experienced on this planet for millions of years. As we know the forests are the great absorbers of CO. There is a close relation between global warming and population growth. Today the large population on earth is using the technologies which are destructive for the earth. Approximately, 80 per cent of atmospheric C02 increases are due to man’s use of fossil fuels either in the form of coal, gas or oil. A large portion of carbon emission is attributed to the burning of gasoline in internal-combustion engine of vehicles. Vehicles with poor gas mileage contribute the most to global warming. Besides, the sulphur group gas is the most harmful for this. Its contribution is 30 per cent in global warming. This gas is also emitted from the burning of fossil fuels. Increase in global temperatures will cause rise in sea level. It will lead to melting of glaciers, changes in rainfall patterns, increased intensity and frequency of extreme weather. As per the latest survey report the rate of melting of glaciers has seen sharp increase in recent times. Even those glaciers are affected from global warming which have been considered permanent. The shrinking of glaciers is going to pose a major problem of drinking water. The sea levels as a result of melting of glaciers have risen from 0. 35 mm to 0. 4 mm. Scientists have warned in their reports that most of the glaciers will disappear within a period of 15 to 25 years. It will create problems of drinking water and food grains in most of the North American countries. India is not unaffected from it. The Himalayan glaciers have shrunk about 30 per cent after 1970. The rise in sea levels is a major cause of concern. A large number of cities located in coastal areas will submerge in the sea. Besides, many island countries will ultimately â€Å"lose their existence and will be washed away from the surface of the earth. The damage of rising sea levels is diverse. Buildings and roads close to the water could be flooded and they could suffer damage from hurricanes and tropical storms. Experts believe that global warming could increase the intensity of hurricanes by over 50 per cent. In addition, as the sea rises, beach erosion takes place, particularly on steep banks. Wetlands are lost as the level rises. Rise in atmospheric temperature will lead to the outbreak of airborne and water-borne diseases. It would also contribute to the rise in death caused by heat. The problem of drought would be frequent. Consequently, malnutrition and starvation will pose serious challenge before humanity. Global warming is a great threat to the flora and fauna of the earth. A large number of species of them may become extinct. The expanse of desert would increase. Low rainfall and rising temperature could add to the intensity and frequency of dusty storm. This in turn will immensely affect the quality of agricultural land, ultimately causing adverse effect on agricultural produce. It would have far-reaching socio-economic impact. In Indian context, the impact of global warming is a matter of grave concern. As is well known, India is mainly an agricultural country and agriculture here is gamble of the monsoon, e. . largely depending on rainfall. Though it is to affect the whole country, the worst likely impact would be on central and northern India which is high-yielding parts of the country. These are the regions which produce the largest agricultural yield. The rise in atmospheric temperature and fall in rain would naturally result in decline in crop production. Moreover, it would have great effect on biodiversity as well. The growing concerns over global temperatures have led to the nations, states, corporations and individuals to draw out a plan of action to avert the situation. As a result the world’s primary international agreement on combating global warming was reached in Kyoto in 1997 which came to be known as Kyoto Protocol. However, ten years have passed; the situation does not appear to be very changed. It seems that the member countries are not very serious about its devastating effects. In addition, forestation can be of great help in this regard. Planting more trees and reducing timber cuts worldwide will help restore the imbalance. Secondly, we must follow on environmental policy of ‘reduce, reuse, recycle’, i. e. promoting the reuse of anything. Thirdly, the use of fuel-efficient vehicles should be promoted as these vehicles have lower emissions of harmful gases. Fourthly, every individual should be aware of the importance of the protecting environment. Besides, eco- friendly technologies must be promoted, and must be substituted with the technologies which cause great emission of global warming gases. Public awareness campaign can be of great help in this regard because unless each and every individual is aware only governments’ effect cannot bring desired difference. Words Essay on Corruption in India (free to read) Corruption is not a new phenomenon in India. It has been prevalent in society since ancient times. History reveals that it was present even in the Mauryan period. Great scholar Kautilya mentions the pressure of forty types of corruption in his contemporary society. It was practised even in Mughal and Sultanate period. When the East India Company took control of the country, corruption reached new height. Corruption in India has become so common that people now are averse to thinking of public life with it. Corruption has been defined variously by scholars. But the simple meaning of it is that corruption implies perversion of morality, integrity, character or duty out of mercenary motives, i. e. bribery, without any regard to honour, right and justice. In other words, undue favour for any one for some monetary or other gains is corruption. Simultaneously, depriving the genuinely deserving from their right or privilege is also a corrupt practice. Shrinking from one’s duty or dereliction of duty are also forms of corruption. Besides, thefts, wastage of public property constitute varieties of corruption. Dishonesty, exploitation, malpractices, scams and scandals re various manifestations of corruption. Corruption is not a uniquely Indian phenomenon. It is witnessed all over the world in developing as well as developed countries. It has spread its tentacles in every sphere of life, namely business administration, politics, officialdom, and services. In fact, there is hardly any sector which can be characterised for not being infected with the vices of corruption. Corruption is rampant in every segment and every section of society, barring the social status attached to it. Nobody can be considered free from corruption from a high ranking officer. To root out the evil of corruption from society, we need to make a comprehensive code of conduct for politicians, legislatures, bureaucrats, and such code should be strictly enforced. Judiciary should be given more independence and initiatives on issues related to corruption. Special courts should be set-up to take up such issues and speedy trial is to be promoted. Law and order machinery should be allowed to work without political interference. NGOs and media should come forward to create awareness against corruption in society and educate people to combat this evil. Only then we would be able to save our system from being collapsed.

Nvq Level 3

Google search Keeping safe and protecting vulnerable adults from harm and abuse All adults should be able to live free from fear or harm and have their rights and choices respected. To help people who may be being abused or suspect that abuse is happening,  we have published  Ã¢â‚¬ËœKeeping Safe and Protecting Adults' which you can download from this page. It gives more information about types of abuse  and what to do if you suspect abuse. You can also  visit the York Safeguarding Adults website What is adult abuse? There are many different types of abuse, see pdf on this page.It may: * be physical or sexual * involve taking money without permission * include bullying or humiliating * include not allowing contact with friends and family * involve withholding food or medication Abuse can be the result of a single act or may continue over many months or years. Abuse can be accidental, or a deliberate act. An abuser may be  Ã¢â‚¬â€œ a relative, a partner, someone paid to provi de care and services, a volunteer, a neighbour, a friend or stranger. Abuse can happen anywhere: * at home * in a care home * in hospital * in sheltered housing * in supported living centres at day centres and other day services * outside in a public place How can I tell if abuse may be happening? Adult abuse is not always easy to identify as sometimes the nature of the abuse is not visible and/or often the person being abused is afraid to speak out. However, there are some more common signs of abuse, see pdf attached to this page, which if seen may suggest that abuse has occurred. Which adults are vulnerable to abuse? Some adults are less able to protect themselves than others and some have difficulty making their wishes and feelings known. This may make them vulnerable to abuse.They may also be vulnerable because they are in need of community care services due to mental health problems, physical or learning disability, age or illness. In York we are working together with  the Po lice, local Councillors, Health and local independent and voluntary sector organisation to improve and develop further services to keep vulnerable adults safe. We are all  committed to preventing the abuse of adults and responding quickly when abuse is suspected. How can I report adult abuse? If you are being abused, or you suspect someone else is being abused contact us on 01904 555111  or North Yorkshire Police on   0845 60 60 247.By reporting abuse you are alerting the council or the police to concerns which may affect more than one person. There is a form which has been designed to help anyone who may suspect abuse is happening and wants to report it. The form is called the Alerters Form, see pdf attached to this page, and is a useful guide to the information that we or the Police will need to know when an incident of abuse is reported. You should also give your name so that we can keep you informed. We will not share your name without your permission. We will then investi gate your concerns and take appropriate action.You can also share your concerns with a Doctor, Nurse or Health Worker, Housing Officer or advice centre (CAB) and ask them to contact us for you. For domestic abuse you can also contact the Independent Domestic Abuse Services email: [email  protected] org. uk web address www. idas. org. uk or telephone 03000 110 110. Adults in care If you are concerned about the quality of care provided by a nursing home, residential home, or domiciliary provider you should contact the  Care Quality Commission  on tel: 0300 061 6161. See the  Care Quality Commission  website for more information www. cqc. rg. uk   How do we respond to adult abuse? In 2007, The City of York Council  endorsed the Multi-Agency Policy and Procedures for Safeguarding Vulnerable Adults. This framework is intended to ensure a consistent response so that various agencies can work together more effectively. This policy is available to download on the right hand si de of this page. What is ‘No Secrets’? This is government guidance issued in 2000, encouraging social services authorities to work with other agencies to develop and implement policies and procedures to ensure protection of vulnerable adults.In 2008, the government began a national consultation exercise to review the No Secrets guidance. The consultation has recently ended and any recommendations for changes are expected later this year. What is  the York Safeguarding Adults Partnership Board? Prior to 2008, there was a City of York and North Yorkshire Adult Protection Committee with the main objective ‘to protect adults from abuse by effective inter-agency working'   As part of a review of the multi-agency policy, it was recognised that the interests of people in York would be better served by a local multi-agency group.So, in 2008, the York Safeguarding Adults Board was set up, with the remit to safeguard vulnerable adults from abuse and harm by effective in ter-agency working. The Board membership is made up of lead officers from social services, the police, health, housing,  the independent care sector, the Crown Prosecution Service, the Care Quality Commission and voluntary organisations.It meets quarterly to consider new developments in adult protection, review the way that the policy is carried out locally and to agree appropriate funding and training. Help for adults * Carer's assessment of need * Disabled bus pass * Educational benefits * Home care service * Out of hours social services support * Safeguarding vulnerable adults * Residential care * Respite care * Sheltered housing * Support for adults with HIV * Supporting people team Nvq Level 3 Google search Keeping safe and protecting vulnerable adults from harm and abuse All adults should be able to live free from fear or harm and have their rights and choices respected. To help people who may be being abused or suspect that abuse is happening,  we have published  Ã¢â‚¬ËœKeeping Safe and Protecting Adults' which you can download from this page. It gives more information about types of abuse  and what to do if you suspect abuse. You can also  visit the York Safeguarding Adults website What is adult abuse? There are many different types of abuse, see pdf on this page.It may: * be physical or sexual * involve taking money without permission * include bullying or humiliating * include not allowing contact with friends and family * involve withholding food or medication Abuse can be the result of a single act or may continue over many months or years. Abuse can be accidental, or a deliberate act. An abuser may be  Ã¢â‚¬â€œ a relative, a partner, someone paid to provi de care and services, a volunteer, a neighbour, a friend or stranger. Abuse can happen anywhere: * at home * in a care home * in hospital * in sheltered housing * in supported living centres at day centres and other day services * outside in a public place How can I tell if abuse may be happening? Adult abuse is not always easy to identify as sometimes the nature of the abuse is not visible and/or often the person being abused is afraid to speak out. However, there are some more common signs of abuse, see pdf attached to this page, which if seen may suggest that abuse has occurred. Which adults are vulnerable to abuse? Some adults are less able to protect themselves than others and some have difficulty making their wishes and feelings known. This may make them vulnerable to abuse.They may also be vulnerable because they are in need of community care services due to mental health problems, physical or learning disability, age or illness. In York we are working together with  the Po lice, local Councillors, Health and local independent and voluntary sector organisation to improve and develop further services to keep vulnerable adults safe. We are all  committed to preventing the abuse of adults and responding quickly when abuse is suspected. How can I report adult abuse? If you are being abused, or you suspect someone else is being abused contact us on 01904 555111  or North Yorkshire Police on   0845 60 60 247.By reporting abuse you are alerting the council or the police to concerns which may affect more than one person. There is a form which has been designed to help anyone who may suspect abuse is happening and wants to report it. The form is called the Alerters Form, see pdf attached to this page, and is a useful guide to the information that we or the Police will need to know when an incident of abuse is reported. You should also give your name so that we can keep you informed. We will not share your name without your permission. We will then investi gate your concerns and take appropriate action.You can also share your concerns with a Doctor, Nurse or Health Worker, Housing Officer or advice centre (CAB) and ask them to contact us for you. For domestic abuse you can also contact the Independent Domestic Abuse Services email: [email  protected] org. uk web address www. idas. org. uk or telephone 03000 110 110. Adults in care If you are concerned about the quality of care provided by a nursing home, residential home, or domiciliary provider you should contact the  Care Quality Commission  on tel: 0300 061 6161. See the  Care Quality Commission  website for more information www. cqc. rg. uk   How do we respond to adult abuse? In 2007, The City of York Council  endorsed the Multi-Agency Policy and Procedures for Safeguarding Vulnerable Adults. This framework is intended to ensure a consistent response so that various agencies can work together more effectively. This policy is available to download on the right hand si de of this page. What is ‘No Secrets’? This is government guidance issued in 2000, encouraging social services authorities to work with other agencies to develop and implement policies and procedures to ensure protection of vulnerable adults.In 2008, the government began a national consultation exercise to review the No Secrets guidance. The consultation has recently ended and any recommendations for changes are expected later this year. What is  the York Safeguarding Adults Partnership Board? Prior to 2008, there was a City of York and North Yorkshire Adult Protection Committee with the main objective ‘to protect adults from abuse by effective inter-agency working'   As part of a review of the multi-agency policy, it was recognised that the interests of people in York would be better served by a local multi-agency group.So, in 2008, the York Safeguarding Adults Board was set up, with the remit to safeguard vulnerable adults from abuse and harm by effective in ter-agency working. The Board membership is made up of lead officers from social services, the police, health, housing,  the independent care sector, the Crown Prosecution Service, the Care Quality Commission and voluntary organisations.It meets quarterly to consider new developments in adult protection, review the way that the policy is carried out locally and to agree appropriate funding and training. Help for adults * Carer's assessment of need * Disabled bus pass * Educational benefits * Home care service * Out of hours social services support * Safeguarding vulnerable adults * Residential care * Respite care * Sheltered housing * Support for adults with HIV * Supporting people team

My Autobiography On Mathematics I Do Not Think Am Good...

My Autobiography in Mathematics I do not think am good or bad in mathematics. I usually fight hard in some areas, however it becomes very easy for me once I get the concept. I do struggle much to ensure that I work out my assignments, tests and other class works. I try my best to finish my math work accurately and am looking forward that I retain the spirit till I finish school. Once a new topic is introduced to class, I normally struggle to understand the concept in the first days of the teaching. This enables me to easily complete different worksheets involving that topic. The problem arises when examination or contests come along. I abruptly found myself blank- I just forgot everything. My big challenge was in vectors. Vectors really†¦show more content†¦Mathematics widens the mind to think critically. It is more than measuring, counting and computing. It opens up other subjects- sciences. As far as Mathematics teaching is concerned, the major goal is the involvement of the students in the practice of realizing mathematical ideas and framing process. One of the encouraging worries about learning Mathematics is the point that it opens up the mind to solve problems that require radical order rational skills. These complications and puzzles provoked the curiosity and challenge the inventiveness of individuals. Giving problem solving into the class improves students’ skills and their ability to reason prudently, rationally and creatively. Hugar criticizes the things we might consider about a mathematics class are processes, equations, and word problems, of which learning them, a student has to master to solve problem. Therefore, in the last decades there has been a move to approach the teaching of mathematics through solving of problem. In this paper, I have written my autobiography on mathematics. Literature Review Krulik states that a problem is situation, quantifiable or else that challenges a person or groups of people, which needs determination, and for which the individual sees no seeming path to the solution. There are many definitions put forward by experts. Essentially these definitions have the same meaning while the variances lie only on the ways they formulate them. We have two definitions here;