Wednesday, October 16, 2019
Introduction Essay Example | Topics and Well Written Essays - 250 words - 13
Introduction - Essay Example cess as well as to make original contribution to literature, this paper discusses what criteria a budding restaurants needs to meet in order to set its foot and expand in the highly challenging and competitive contemporary food industry. This paper uses the Porter’s Five-Forces model to examine a restaurant’s competitive environment. Taking McDonald’s as a case study, this paper discusses the threats and opportunities an expanding restaurant faces today and the advantages and disadvantages associated with its strategic moves. McDonald’s is one of the most successful fast food chains of all time. Having achieved such a phenomenal success and expansion in a matter of much less than a century, McDonald’s has a lot to offer new and budding entrepreneurs in terms of mission, vision, strategic decision making, and ways to achieve success. The paper concludes with a set of recommendations for McDonald’s that can help it even improve the pace of its success and the quality of its products and
Tuesday, October 15, 2019
No topic, just answer the following questions Research Paper
No topic, just answer the following questions - Research Paper Example Sale of the company would realize a profit return of about 4.39 million dollars (30) PressureShot Management structure proved to be a good plan for the company. The company’s operations would run smoothly and reliably because of the excellent corporate structure. Product brand chosen would improve public image and profit returns. Increased profit and market share results from the monopoly status of the company. PressureShot is the sole producer and service provider in tennis industry (Thuell, King, and Dennison). The company also boost of good Customer service plan that would improve its relations both locally and internationally. PressureShot strengths besides excellent customer service provision also include fantastic products that are long lasting (17). Based on PressureShot structure on capacity levels and inventory management, the company ought to have created its own storage facilities. Although trusting Sandstrom manufacturing company with storage, production, and shipment of company paints increases convenience, it would be expensive in the end. Installation of storage and paint manufacturing facilities will not only reduce operations costs but also remain as Company’s assets (21). Though the exit strategy promised good return on investment, it is immature as the company still has space for
Theoretical Paradigm To Analyze A Current Newspaper Article Essay Example for Free
Theoretical Paradigm To Analyze A Current Newspaper Article Essay From a functionalist perspective, social institutions such as families and governments are analyzed and explained as collective means to satisfy specific or individual biological requisites. These social institutions, along with the rest, are composed of interconnected roles or norms such as the interconnected roles within the family (e.g. father, mother, etc.).            As it essentially concerns the workings and the very structure of the society, the functionalist perspective views the society as composed of interdependent branches which work together to meet the functions needed for the general society’s survival. Moreover, as functionalists understand that the behaviors within the society are primarily structural in nature, the functionalist perspective delves into the socialization of individuals defined according to their specific and contingent behaviors and roles which satisfies the society’s necessities.            It is also the sociological perspective which believes that rules and regulations aid in organizing the social relationships among the members of the whole society. In essence, the functionalist perspective is founded on the concept that the society is a whole system composed of the totality of interdependent segments. It is also founded on the belief that functional requirements must be satisfied for the survival of the society. Lastly, it is also founded on the presumption that phenomena are accepted to exist as they are functional within the society.            In the case of the family of Eric Alan, the worth of his family proves the idea that the family as a social institution has interconnected roles with the larger society. In particular, having to redesign his familys home into something more breathable exemplifies the presumption that the individual roles in the family, such as the role of the father to provide an inhabitable home for his family, and the family in general is tied with the other segments of the society in such a way that one reinforces the values of the other and vice versa.            Featured in the November 8 issue of the New York Times, A Crowded Family Enters the Space Age conveys the story of a father wanting to provide a larger house for his growing family with the aid of Architect Neil Denari. In return, Denaris expertise and skills acquire a living experience thus proving to be another feat not only in his career as an architect but also in the discipline of architecture. From a functionalist perspective, this very well provides a real life example of how the units of the society interact together harmoniously in order to continue with survival.            The subject of the article is sociological for a number of reasons. First, the primary concept involved in the article is family, which is considered to be the basic functioning unit of the society, which is also explained and analyzed in terms of its growth. Second, and in relation to the first reason, the growth of the family involves the help of an external unit exemplified in the article as the architect embodying one of the other units in the society. Third, this relation can be seen as a form of interdependency in the sense that the growing family requires the help of the architect and that the role of the architect is to be fulfilled in terms of the help needed by the family. Finally, this situation can be projected from a larger perspective and can be related to the various segments of the society, thereby highlighting the existing interdependencies existing in the society.            The family in the society, being its basic functioning unit, can be described as having its own set of interconnected norms or roles from within using the functionalist perspective. By norms and roles, what is being meant are the individual roles and functions of the members of the family. Eric Alan, being the father of his family, has the role of securing his familys welfare. And one of these ways to secure family welfare is to provide a suitable home especially for a growing family of three daughters.            Since the society is believed to be composed of interdependent units from the functionalist perspective, it can be assumed that other units share a definitive role in achieving the aims of the family as a single unit. In Eric Alans case, it can be observed that in order to achieve his goal of providing a larger shelter for his growing family, Mr. Alan sought the help of an architect specializing in refurbishing structures such as houses. This instance points us to the sociological idea that the family, in certain circumstances, would have to depend on the capabilities of other sectors of the society.            Without the help of a specialist, Mr. Alans goal would hardly be attained if it can be attained at all solely on his familys own. Considering the fact that Mr. Alan and his wife have their own work-related affairs to deal with, and with their children attending the local school, doing things on their own is simply not a practical option. As a result, they sought the help of Architect Neil Denari which seals the core idea that the family is interdependent on the other segments of the society in at least one way.            On the other hand, this dependency of the family is not an isolated form of dependency. Quite on the contrary, it can be seen from the functionalist perspective as a form of interdependency wherein one unit depends on another unit in order to realize its objectives and vice versa. While the family sought the help of an architect representing the discipline of architecture, the architect, in order to fulfill his obligations and norms or roles would have to acquire the services being sought by the other segments of the society. Otherwise, these roles or norms would not be realized.            Moreover, the functionalist perspective will interpret the roles of the architect as primarily structural in nature. This is in the sense that there is a form in the role and behaviors of the architect with regard to its functioning in the society. The provision of service to the family of Mr. Alan by Architect Denari is not a mere servicing devoid of certain procedures. There is a scheme which Denari is required to follow in order to carry out his role and provide the family of Mr. Alan the service that they require.            The specific scheme upon which Denaris role operates revolves around the details of his position as an architect. This corresponds to a set of either written codifications that serve as guide for acting in good faith on behalf of the larger domain of architecture, or a set of accepted norms. These norms can be ethical or professional norms which serve as templates for the actions or behavior of Denari as an architect. More importantly, all of these represent the general idea that norms or rules serve as framework for the individual behaviors or actions of individuals under a specific segment of the society. The structures of these units (e.g. family, the individual architect) are notably in the form of a specific and well-established format where deviance may either face the equivalent sanctions or condemnation.            In any case, the structure for each unit is an essential composition for the very existence of these social units. The structure of Mr. Alans family, for instance, follows that of the conventional structure of father, mother, and children whereas the structure of Architect Denaris role is founded upon the precepts, doctrines, or established rules of norm for his discipline. More specifically, the structure of Mr. Denaris role follows the conventional processâ€â€a surveying of the site specifically the house of Mr. Alans family, the preparation of the plans and procedures, and the actual execution of the architectural process.            The essence of all these things corresponds to the presumption that there is a form of interdependency between these two social units: the family of Mr. Alan and Architect Denari. Further, this interdependency is based on the existing needs and roles of the two social units whereas the separate needs and roles of any of the two social units are founded on the established norms and rules. This leads us to the final point: the given situation can be projected from a larger perspective and can be related to the various segments of the society, thereby highlighting the existing interdependencies existing in the society as prescribed by the functionalist perspective.            There are numerous social rules and norms predominant in the world, and most of these specific norms are relative to every individual society, country, or culture. While there may be irregularities among these sets of norms and rules as a result perhaps of cultural differences, there still remain the structure for the individual rules and norms for these societies.            The world can be considered as the summation of the existing societies and is perhaps a whole society on its own. There are rules and norms that govern the world even from such a massive scale, such as the norms and rules for human conduct in social interaction. Perhaps no society is inclined to allowing its members from inflicting harm to one another, and out if this broad perspective several other specific and detailed rules and norms branch out. The differencesâ€â€quite on the contrary of believing that these are indicators of a non-structured world as the largest societyâ€â€indicate that there separate structures of norms and rules operating amongst the various sectors of the world.            The functionalist perspective indeed allows us to view the sociological ideas behind the case of Mr. Eric Alans family and Architect Neil Denari. The specific sociological factors involved further allow us to view and analyze the larger stream of sociological interactions occurring throughout the different parts of the world. References Mahner, M., Bunge, M. (2001). Function and Functionalism: A Synthetic Perspective. Philosophy of Science, 68(1), 75-94. Webb, M. (2007, November 8). A Crowded Family Enters the Space Age. New York Times.
Monday, October 14, 2019
The Structure Of Protein P53 Biology Essay
The Structure Of Protein P53 Biology Essay Protein p53, encoded by gene Tp53, is known as a tumor suppressor. Discovered in 1979 as a transformation-related protein (DeLeo et al., 1979) and protein which accumulates in the tumor cells binding with simian virus 40 (SV40) large T antigens (Lane et al., 1979), p53 was regarded as an important protein in the regulation of an apoptosis and cancerization. During the last 30 years, a large amount of studies was taken in p53 and its related mechanisms in cellular process. In 1980s, researchers cloned the Tp53 gene and determined the role of p53 as a tumor suppressor. However, the structure of p53 protein was uncertain until 2006, in which William and his colleagues determined the DNA binding core domain of protein p53 (William. C. Ho. et al., 2006). Plenty of researches focus on the regulatory mechanism of p53 and hundreds types of targets and regulators of p53 were found, e.g. MDM2, Cyclin H, ATR, ATM, etc. These molecules can interact with p53 and regulate the life process collecti vely. P53 plays a very crucial role in cell cycle regulation and apoptosis induction, the mutation of p53 would lead to the cancerization in cells and induce cancer. Bai and Zhu (2006) reported that the mutation or loss of p53 gene and protein can be found in over 50% of tumor cells in human all around the world. For these reasons, the application of cancer therapy through protein p53 and Tp53 gene is a very potential aspect in cancer treatment. This review will describe the structure and function of p53 protein, examine its role in natural and tumor cells and focus on the cancer therapy application through p53. The Structure of P53 Human protein p53 is a 53KDa phosphoprotein encoded by a 20Kb-gene; it has an intricate structure which is closely related to its function. Wild-type P53 protein contains five major domains. The N-terminus of p53 is a transcription-activation domain (TAD), with a major one at residues 1-42 and a minor one at residues 55-75 (Venot et al., 1998). The basic function of this domain is involvement in the regulation of the pro-apoptotic transcription. Following the TAD is a proline-rich region which plays an important role in apoptotic activities. The central core of p53 protein is a DNA binding domain which can bind and interact with special DNA sequence that contain 2 copies of 10bp motif 5-PuPuPuC(A/T)-(T/A)GPyPyPy-3 (Kern et al., 1991). This region is also responsible for binding with LMO3, which is an essential co-repressor of p53 (Larsen et al., 2010). A nuclear localization signaling domain (NLS) is located beside the C-terminus of central core. The C-terminus domain of p53 protein, called negative regulatory domain is involved in the down regulation of DNA binding in central core (Chen, et al., 2005), and is also an essential part for the induction of cell death. A homo-oligomerisation domain (OD) located between the negative regulatory domain and NLS. This part is involved in tetramerization, which is a main activity for p53 in vivo. The different domains of p53 protein have their functions respectively, nevertheless, they constitute an inseparable entirety to play the role as a tumor suppressor. The function of p53 As a cancer suppressor, the main function of p53 is the anticancer function. P53 plays a vital role in apoptosis, gene stability and DNA damage through a series of complex mechanisms. First, p53 can respond to DNA damage through activating the DNA repair protein. For example, upon DNA damage, p53 gets activated and initiates the transcription of repair protein XPC and DDB2. The complex of p53-XPC-DDB2 can repair the DNA damaged by UV (Adimoolam and Ford, 2003). In addition, p53 can arrest the cell cycle at S, G1, and G2 phase (Agarwal et al., 1995), which can provide sufficient time for proteins repair to fix the damaged DNA. Induction of apoptosis, the programmed cell death, is also the essential and most important anti-cancer function of p53. If DNA damage is irreparable, p53 can activate the expression of pro-apoptosis genes like p21, Gadd45 (growth arrest and DNA-damageinducible protein 45), Bcl-2 family, etc. Moreover, p53 can bind and interact with hundreds of protein to regulate the cellular process and apoptosis. P53 can also restrain the cell cycle by repressing the expression of genes include bcl-2, bcl-X, cyclin B1, MAP4 and survivin (Bai and Zhu, 2006). The physiological functions of p53 are to maintain the genetic stability and regulate the normal cell cycle through a complex regulatory network. The mutation of Tp53 gene would lead to the loss of function of p53 protein, resulting in a cellular canceration. Consequently, the essential function of p53 is preventing the cancerization of cells by repairing genes or inducing apoptosis, in order to achieve these function, p53 can interact with a n umber of downstream targets. The Regulation in P53 Level A large amount of cellular response and process is induced by p53 through a series of complex biochemical mechanisms. P53 achieves its function through activating, binding, interacting with myriad kinds of downstream target molecules including kinase, enzymes, etc. Generally, p53 interacts with its target by phosphorylation of transcription-activation domain in N-terminus. The most well-known target of p53 is a cyclin-dependent kinase (CDK) p21. P53 would initiate the transcription and transduction of p21 in response to cellular stress, p21 is necessary in G1 control, the increase of p21 arrest the cell growth and induce cell death (Yin, et al., 1999). P53 and p21 contribute to a cell-cycle check point in G1 phase. The damaged genes would not be allowed to express until they are repair. If most damaged genes cannot be repaired, the accumulation of p21 regulated by p53 would induce apoptosis. Another important target of p53 is MDM2 (also called HDM2 in human body). MDM2 is a p53 inducible gene and its product can bind and interact with p53. The product of MDM2 gene, called p90 or p95, can bind with p53 and combine with ubiquitinate which can induce the degradation of p53 (Buschmann, et al., 2000). MDM2 is the killer of p53 which can keep the amount of p53 proteins into an appropriate level. However, a series of cellular stress would cause the overexpress of MDM2 and result in the over degradation of p53, the cell would lose ground and transform to tumor cell. P53 has plenty of other regulation pathways that cannot be listed in detail. The hundreds of pathways regulated by p53 have two mutual purposes: repair genes and induction of apoptosis. Therefore, the core of the p53 regulation levels is to maintain the stability of genes and accelerate the death of damaged or diseased cells. The Role of p53 in Normal and Tumor cells In natural human cells, the wt-p53 protein can be regarded as a guardian of the cell and genome. It can monitor the vital process, repair the gene indirectly through interaction with repair protein and induce apoptosis when necessary (Hofseth, et al., 2004). P53 plays a crucial role in numerous cellular processes which are related to cell cycle and cell death. If Tp53 gene mutated, the tumor suppression function in the cell would partly reduce. As a result, people whose Tp53 gene was mutated are more susceptible to suffer from cancer. Tp53 gene is mutated in over half of tumor cells; the mutation would alter the structure of p53 protein, thus p53 would lose its function partly or completely. The p53-mutated cells can not die programmatically, and become tumor cells. The mutated p53 protein tends to accumulate in tumor cells because the mutated p53 lose its function to induce the express of MDM2, which can degrade p53 proteins in the cell. The accumulation of p53 protein is a significant feature for the tumor cells. In cancer treatments, tumor cells can be detected through the accumulation of p53. However, mutated p53 can also be an obstacle of the therapy because mutant p53 can inhibit the function of wide-type p53 (Blagosklonny, M. V., 2002). If the treatment strategy is transferring the wide-type p53 into tumor cells, how to eliminate the effect of mutant p53 is the problem which has to be solved first. Consequently, p53 plays crucial roles both in normal cells and tumor cells; it is a gatekeeper in normal cells and a marker for tumor cells; it is an effective target for cancer treatments, nevertheless it can also become a barrier in cancer therapy. Conclusion P53 is the best-known transcription factor and cancer suppressor plays multiple roles in the cell. In healthy cells and, it is a gatekeeper to monitor the cell cycle and prevent the mutation of gene. If some mutations happen in the genome, p53 serve as a doctor to activate the repair process of damaged genes. When cells suffer from an irreversible damage or oncogenic stress, p53 can become a killer of cancerous cells. P53 participates in a number of biochemical pathways which can respond to the stress, arrest cell-cycle, repair gene and induce apoptosis. In the 30 years after the discovery of p53, plenty investigation was devoted into this essential protein and received a number of great achievements. A large amount of downstream targets has been identified and the regulatory network of p53 levels became clearer. Although plenty of details about p53, such as the relationship between each pathway, are still unknown. There is still a potential application through p53 in cancer treatmen ts.
Sunday, October 13, 2019
Campaigning for the Presidential Election of 2000 :: Presidential Election Politics Presidents Essays
Campaigning for the Presidential Election of 2000 The 2000 Presidential campaigns were a very close call according to the poles made by CNN with Gore in the lead at 43 percent and Bush with 42 percent. The main Presidential candidates were Vice President Al Gore representing the Democrats and the Governor of Texas, George W. Bush, representing the Republicans. The candidates disagreed on some issues that included abortion, healthcare, and education. However, they did agree on some things but had very different methods on obtaining their goals. Abortion, for example, is one issue they viewed differently because Bush was pro-life and Gore was pro-choice. Healthcare was extremely important in this campaign because Gore wanted to help the elderly more, which was one of the main points of his campaign, and this ended up hurting Bush. The biggest issue happened to be education. Both wanted education to excel while they were President but had different ways of going about it. When it came to the abortion issue, I thought it was the one that mainly pulled in the women’s’ votes. Gore supported abortion rights and Bush opposed them except in cases of rape, incest, or to save a women’s life. The Gore administration was better off on this one because Gore was for it and so were a lot of women. On the CBS news Bush stated, â€Å"He would support a Constitutional Amendment to ban abortion but wouldn’t push for one.†In relation to his statement Bush said, â€Å"I don’t believe there is enough public support for it.†A major issue that Gore had over Bush is that Bush opposed the FDA approval of the abortion pill, Mifeprex, while Gore believed the pill would be a better way to get an abortion done. Gore also opposed parental consent or notification which helped pull in many of the younger women’s votes. On the other hand, Bush was for parental consent that caused many of the parent population to be on his sid e. Healthcare was a major issue concerning the elderly and was very helpful when it came to the swing states and whom they were going to vote for. For example, Washington was a swing state, in the past ten elections, five were for Republicans, and the other five were for the Democrats. It could have went either way but looked like it ended up in the favor of Gore.
Saturday, October 12, 2019
The Glaciers of Yosemite National Park Essay -- Geology
The Glaciers of Yosemite National Park One of nature's most powerful and influential forces is also one of nature's coldest and slowest processes. These great icy rivers are called glaciers and have formed some of the most beautiful scenery on this planet. These enormous frozen bodies of water are often thousands of feet wide and deep and many miles long. They cover millions of acres of land and drastically change the land into beautiful mountains with many amazing features. One of the areas where glaciers have been most influential is in Yosemite National Park in California. Here almost every glacial feature is shown. However, before this information about glaciers in Yosemite was clear, there was the Yosemite Controversy with arguments of different views of how the valley originated. Glaciers are best described in this passage by naturalist John Muir: (Bailey) (Guyton) The work of glaciers, especially the part they have played in sculpturing the face of the earth, is as yet but little understood, because they have so few loving observers willing to remain with them long enough to appreciate them. Water rivers work openly where people dwell, and so does the rain and the dew, and the great salt sea embracing all the world; and even the universal ocean of air, though invisible, yet it speaks aloud in a thousand voices, and explains its modes of working and its power. But glaciers, back in their cold solitudes, work apart from men, exerting their tremendous energies in silence and darkness. Outspread, spirit-like, they brood above the long predestined landscapes, working on unwearied though unmeasured ages, until, in the fullness of time, the mountains and valleys and plains are brought forth, channels furrowed for the rive... ... which shaped the valley even more. Rockfall has shaped the Royal Arches and Mirror Lake. Recently in July of 1996, there was a large rock fall and in January of 1997 the Merced River flooded proving that the geology of Yosemite is a forever changing process that still goes on to this day. (Guyton) Bibliography Bailey, Ronald H. Planet Earth: Glacier. Time-Life Books: Alexandria, 1982. Guyton, Bill. Glaciers of California. University of California Press: Berkeley, 1998. Huber, N. King. The Geologic Story of Yosemite National Park. Yosemite Association: Yosemite National Park, 1989. Lutgens, Fredrick K. and Edward J. Tarbuck. Earth Science. Prentice Hall: Upper Saddle River, 2002. Matthes, Francois E. The Incomparable Valley. University of California Press: Berkeley, 1950. Tierney, Tim. Geology of the Mono Basin. Kutsavi Press: Lee Vining, 1995.
Friday, October 11, 2019
Horticultural Machineries Essay
Horticultural machinery are the various tractors, rotary cultivators, drills, sprayers, root vegetable harvesters and other equipment of interest to horticulturist POWER UNITS USED FOR HORTICULTURAL PURPOSES The need for special types of power unit and or cultivation implements arises when it is necessary to work between fruits trees or halyard, where the planting distance has already been decided and the equipment has to conform to it. narrow rows of fruits and haps sometimes necessitate the use of extremely narrow tractors, with overall widths of about 4 ft (1. m) such tractors require specially adapted mounted equipment and use among other implements, types of plough which are designed for plugging up or away from both sides of rows of haps or fruits some of special cultivation implements used include. 1. SMALL ROTARY CULTIVATORS A rotary cultivator is a tool that is used to loosen, aerate and prepare soil for new planting or to enhance the condition of soil for existing plantings . A rotary cultivator often known as rotatiller or roto cultivator consists of sharp rotating tins or blades that are typically made of steel or aluminum. The rotating tins dig into the soil, loosening and aerating the soil in a process known as cultivation. Cultivating soil is important because over a period of time soil tends to compact and harden. This can make it more difficult for plant to receive the proper level of water and nutrients. Breaking up and loosening compacted soil makes it easier for water and nutrients to flow through the soil and into plantings. A small rotary cultivator is hand held cultivator either self propelled or powered. It looks much like a lawn mower. A self propelled rotary cultivator has tins (blades) attached to a pole that is similar to a long stick and the user simply pushes it to cultivate a lawn or garden. Many self propelled cultivators have aluminum tines which some users have found to be too light weight for anything more than light grader use. There are therefore self-propelled cultivators that utilize a heavier weight metal for the rotating tines, which many find to be more effective. However, the heavier weight of these tools may make it more difficult to use for an extended period of time. A motorized cultivator is powered by a small gasoline or electric motor; it is often used on large gardens. The tines of a rotary cultivator rotate in the opposite direction of the wheel and till to a depth of 8 to 10 inches normal width of the small rotary cultivator range from 4 – 8 ft (2 – 2. 4m) with power rating ranging from 1 hp to 8 hp (0. 75kw) 2. WALKING TRACTOR The walking tractor or two-wheel tractor is a tractor with one axle self powered and self-propelled which can pull and power various farm implements such as a tractor, cultivator, or harrow, a plough or various seeders and harvesters. The operator usually walks behind it or sides the implement being towed like a four-wheel tractor, the walking tractor is designed to run many attachments with a single power source and gives thousands of hours of services. These tractors are fitted with engines of up to 3hp (2. 2 kw). Some walking tractors now constructed have a power rating of up to 12 hp. 3. NARROW TRACT TRACTOR Narrow track tractors are of interest to horticulturalist who frequently need to pull a heavy spraying machine as well as to carry out plugging and other tillage operations. Such tractors with engines of 25 – 45 hp (19 – 33 kw) may have overall dimensions as small as about 1m wide as 1. 3m high. They are fitted with 4 tyres and articulated frame steering of a type that can provide a very small turning circle, they have low weight to permit work beneath trees. Hydrostatic transmission assists in achieving a sound method of delivering power to the drive wheels. 4. COMPACT L-WHEEL TRACTOR A compact utility tractor (CUT) is a smaller version of an agricultural tractor designed primarily for landscaping and use in field with narrow spaced tracks. Typical CUTs range from 20 – 50hp (15 -37 kw) with available PTO horse power ranging from 15 – 45 (11 -34 kw) CUTs are often equipped with both a mid-mounted and standard rear PTO, especially those below 40 hp (30 kw). modern CUTs use hydrostatic transmissions but many variants of gear-drive transmissions are also offered from low priced, simple gear-transmission to advance glide-shift transmissions. CUTs require special smaller implements than full sized agricultural tractors. Very common implements include, the box blade the grader blade, the landscape rake, the post hole digger, the rotary cutter, a broadcast seeder, and a rotary tiller. SOIL CULTIVATION IMPLEMENTS 1. PLOUGH The plough is a tool used in farming for initial cultivation of soil in preparation for sowing seed or planting. It has been a basic instrument for most of recorded history and represents one of the major advances in agriculture. The primary purpose of plugging is to turn over the upper layer of the soil, bringing fresh nutrients to the surface while burying weeds and weed seeds, allowing them to breakdown. It also aerates the soil, allows it to hold moisture better and provides a seed-free medium for planting on alternate crop. The plough is made up of the following components: . The Coulter The function of the coulter is to cut the soil. It is this component of the plough that clears the path. The coulter is a blade or sharp-edged disc attached to a plough so that it cuts through the soil vertically. 2. The Mold Board It is the part of the plough which pushes aside the soil, turned over by the coulter. It is either cylindrical, helical, helical ly cylindrical or a curved rod. 3. Plough-Beam The part that connects the rest of the plough with the animal or tractor. Its shape and length influences the depth of the coulter and to a lesser extent ts width. 4. Plough Share The plough-share is the central part of the plough on which the other major parts are fixed (plough-beam, mold boards coulter, contre-sep). 5. Contre-sep Allows the stabilization of the plough while supporting the hilt. Any standard steel can be used for its construction. 6. The Hilt Permits the longitudiral stabilization of the plough pliding on the bottom of the trench longitudinal stability is ensured by reaction between the ground supports on the soil, the support points on the front and the rear of plough and by the wheel. SOIL STERILIZATION Soil sterilization is a chemical or physical process that results in the death of soil organisms. This practice provides secure and quick relief of soil from substances and organisms harmful to plants such as bacteria, viruses, fungi, nematodes and other pests. Many of the organisms in the soil helps breakdown larger pieces of organic matter into small particles which are more easily absorbable by plants but they could be in the soil detrimental fungi, bacteria and insects and weed seeds. Soil sterilization helps to do away with these detrimental organisms and seed weeds. There are two major methods of soil sterilization: Chemical method and physical method. 1. Chemical methods includes the use of herbicides and fumigants 2. Physical methods include the use of steam and solar energy a. STEAM STERILIZATION Soil steaming is a farming technique that sterilizes soil with steam in open fields or green houses. Detrimental organisms and weeds are killed through induced hot steam which causes their cell structure to physically degenerate. Biologically, the method is considered a partial disinfection. Important heat-resistant, spare-farming bacteria survive and revitalize the soil after cooling down. Steaming leads to a strengthened resistance against plant disease and pests. METHOD OF STEAMING 1. Surface steaming: it is the application of heat directly on the surface of the soil using various methods which include area sheet steaming, the steaming hood, the steaming harrow, the steaming plough and vacuum steaming with drainage pipes or mobile pipe system. i. Sheet steaming: Surface steaming with special sheets is a method which has been established for decades in other to steam large areas reaching from 15 to 400m2 in one step. The usage of heat resistant, non-decomposing insulation fleece saves up to 50% energy reduces the steaming time significantly and improves penetration. The streaming time depends on soil structure as well as outside temperature and amounts to 1 – 1. 5 hour per 10 cm steaming depth. ii. Steaming with Vacuum: This is induced through a mobile or fixed installed pipe system in the depth of the area to be steamed. It is the method that reaches the best penetration. Despite high capital cost, the fixed installation of drainage system is reasonable for intensively used areas since steaming depth of up to 80 cm can be achieved. The steaming area is covered with a special steaming sheet and weighted all around as with sheet steaming. The steam is injected underneath the sheet through an injector and protection tunnel while with short areas up to 30m length steam is frontally injected, with longer areas steam is induced in the middle of the beet using a T-connection branching out to both sides. As soon as the sheet is inflated to approximately 1m by the steam pressure, the suction turbine is switched on. First, the air in the soil is removed via the suction hoses. A vacuum is formed and the steam is pulled downward. When the required steaming depth has been reached, the ventilator runs non-stop and surplus steam is blown out. To ensure that, this surplus steam is not lost, it is fed back under the sheet. iii. Steaming with hoods A steaming hood is a mobile device consisting of corrosion resistant materials such as aluminum, which is put down on to the area to be steamed. In contrast to sheet steaming, cost-intensive working steps such as lying out and weighting the sheet don’t occur, however the area steamed per working step is smaller in accordance to the size of the hood. . SOLARIZATION Solarization of soil is a much more non-chemical; environmentally friendly way of soil sterilization and this involves using the power of the sun to get rid of many disease and pests that causes damage to different types of grasses. It is a relatively easy method of sterilization and involves covering up the soil that will be established with a clear plastic material to capture the radiant heat and energ y from the sun to kill the pathogens in the soil. Not only does this method get rid of most of the unwanted diseases and pests but it also stimulates the relense of nutrients from organic matter present in the soil. c. ELECTRIC SOIL STERILIZER The electric soil sterilizer is often used for sterilization of small quantity of soil needed for the nursery or in green houses. The equipment is filled to the top of the container and then the unit is plugged in. the thermostat is then set to the correct sterilizing temperature (about 80 °c). The indicator light will glow until the batch is done. After the light goes off, wait 15 minutes, then pick up the unit and the sterilized soil will drop out the bottom. It eliminates weeds and disease, kills weeds practically 100% kills soil-borne insects and in general, all of the bacteria, fungi and virus organisms that are harmful to commercial crops. d. CHEMICAL SOIL STERILIZATION Chemical sterilization of soil refers to the use of various chemical to sterilize soil. The chemicals to be used must give off gas which is sufficiently toxic to ensure the destruction of pest, diseases and weeds, yet without harming the beneficial, organisms in the soil. The efficiency of chemical sterilization varies greatly, not because of precise chemicals involved, but because of the condition of the soil, its moisture content and most importantly, the prevailing temperature. This should also ensure even distribution in the soil to be sterilized some chemicals used for soil sterilization include: 1. Methyl bromide gas Methyl bromide is a fumigant that is most often used in vegetable and farm production. It is usually applied s gas injected into the soil and then covered by a thin plastic shield in order to slow the movement of methyl bromide from the soil to the atmosphere in that specific area. It is a dangerous chemical and when humans are exposed to high concentrations of this chemical it can result in respiratory system failure, central nervous system failure and damage to the skin, eyes and lungs. Because of the dangers associated with the application of this gas and the detrimental effects that it has on the ozone, methyl bromide is beginning to become less and less used. 2. Vapam Vapam is an effective liquid fumigant for the control of nematodes, insects, weeds and soil borne diseases. It is not very volatile which means that it is not easily evaporated At normal temperatures and before applying this chemical it is always wise to cultivate the area that is being treated in order to deliver the vapam in a uniform manner; Before application the soil moisture of the field be between 50% to 80% field capacity this chemical can be applied in a number of ways some bring through sprinkler; sprinkler and flood applications provide the best coverage and thus the most successful; this product is however toxic to fish so you should not apply this to areas where the surface water can easily be washed on to lakes or streams, 3. Basamid Basamid is a granular and eliminates weeds, nematodes grasses and soil diseases. When this chemical ingredient hits the moist soil the graduals breakdown and release gases that spread in the soil and these gases eliminate the unwanted disease or pests. When applying basamid it is very important to keep the soil wet for 2 week, prior to the application in order to meet the right soil moisture level and every incorporated on to the soil to about 15cm using a rotary cultivator or something that has this same effect . After doing this, it is important to seal the area with a plastic of some sort of properly fumigate the soil, keeping all the volatile and highly toxic gases in that specific area. SOIL STERILIZING EQUIPMENT (LOKO BOILER) A boilers or steam generator is a device used to create steam by applying heat energy to water. The form and size depends on the application; the locomotive Boiler is portable mobile steam engine with same features as the large one. The only difference is variation in size of component part the LOKO Boiler is made up of the following part; 1. FIRE TUBE BOILER This is a single furnace, three phase type fire tube boiler. Heat-flue gases-travel is through three different sets of tubes. All the tubes are surrounded by water which absorbs the heat . As the water turns to steam, pressure builds up with in the boiler one enough pressure has built up the engineer will open the main steam outlet valve slowly. Fire tube boilers are also known as smoke tube and donkey boiler. . WATER TUBE BOILERS; The large tube like structure at the top of the boiler is called the steam drum. You could call it the heart of the boiler. That is where the steam collects before being discharged from the boiler. The hundreds of tube start and eventually end up at the steam drum. Water enters the boiler, pre-heated at the top. The hot water naturally circulates through the tubes down to the lower area where it is hot the water heats up and flow s back to the steam drum where the steam collects. Not all the water gets turn to steam, so the process starts again. Water keep on circulating until all of it turns in to or becomes steam. BOILER MAIN COMPONENTS; BOILER SHELL- The out cylindrical portion of a pressure vessel. BURNER – A device for the introduction of fuel air in to the furnace at the decreed velocities, turbulence and concentration. The burners is the principal device for the firing of oil and or gas Burners are normally located in the vertical walls of the furnace. Burners along with the furnace in which they are installed, are designed to born the fuel properly. SMOKE TUBE – The second/third phase are formed by thick walled smoke tubes which are welded in to the end plates the arrangement of the smoke tubes considers the recommendation of ascending flue passes in order to prevent the information of residual-or lingering gases the first phase is a combination of a furnace tube and combustion chamber suspended by stay bar and completely surrounded by water giving valuable radiant heat transference from all surfaces. The second pass is a nest of straight 50mm boiler tubes expanded in to the upper zone of the combustion chamber and running in parallel to the furnace tube terminating at the front plate of the reversing chamber. The third pass is a further nest of 50mm boiler tubes running from the upper zone of the reversing chamber to the rear smoke box for exhausting to atmosphere. FRONT REVERSING CHAMBERS – The front reversing chamber is equipped with large doors allowing free access to the smoke tubes and easy maintenance and cleaning High-quality tightening material guarantees the gastight closing of he doors. DRAIN TAP – A valve connection at the lowest point for the removal of all unwanted elements from the pressure parts. FEED PUMP – A pump that supplies water to a boiler. FEED WATER – water introduced into a boiler during operation. It includes make-up and return condensate. FURNACE – An enclosed space provided for the combustions of fuel. INSULATION â₠¬â€œ A material of low thermal conductivity used to reduce heat losses. SAFETY VALVE – A spring loaded valve that automatically opens when pressure attains the value setting used to prevent excessive pressure from building up in a boiler. SAFETY SHUT- OFF VALVE – A manually opened, electrically latched, electrically operated safety shut-off valve designed to automatically shut-off fuel when de-energized. WATER LEVEL – The elevation of the surface of the water in a boiler. ACCUMULATOR – A pressure vessel containing water and/or steam which is used to store the heat of steam for use at a lale period at some lower pressure. FIRE BOX – The fire box is surrounded by water in the outer fire box shell and so absorbing radiant heat from the fire. The gap between the inner and outer fire boxes is maintained by hundreds of rigid stays. AIR ATOMIZING OIL BURNER A burner for firing oil in which the oil is atomized by compressed air, which is forced into and through one or more streams of oil which result in the breaking of the oil into a fine spray. BAFFLE-TYPE COLLECTOR; A device in gas paths utilizing baffle so arranged as to deflect dust particles out of the gas stream. BAG FILTER; A device containing one or more cloth bags revering particles from the dust lateen gas or air which is blown through it . BAG-TYPE COLLECTOR; A filter in which the cloth filtering medium is made in the form of cylindrical bags. BREECHING; A duct that transports the products of combustion between parts of a steam generating unit or to the stack. CIRCULATOR; A pipe or tube to pass stream or water between upper boiler drums usually lactated where the heat absorption is low. Also used to apply to tubes connecting heater of horizontal water tube boilers with drums. STEAM GENERATING UNIT: A unit to which water fuel and air supplied and in which steam is generated. t consists of a boiler furnace and fuel burning equipment, and may include as component parts water walls, super heater, reheater, economizer, air heater, or any combination thereof. STEAM SEPARATOR: A device for removing the entrained water from steam. STRAINER: A device, such as a filter, to retain solid particles allowing a liquid to pass. SMOKE BOX: The smoke box is an extension of the front end of the boiler barrel. Exhaust steam from the cylin der passes through the blast pipe into the chimney and creates partial vacuum. This causes hot gases to be drown through the grate and fine hole door. The smoke box also contains the main steam pipe to the steam chest, blower, super heater header, tube and exhaust for the vacuum ejector where fitted. BRICK ARCH: The brick arch serves several purpose. It protects the fire box tube plate from the direct flame of the fire, radiates heat to prevent rapid fluctuation of the tube plate temperature and ensure thorough combustion of volatiles by lengthening their path from the fire to the tube plate. FIRE DOOR: Fire hole door vary from locomotive to locomotive. They gives access to firing and can be adjusted to control the flow of secondary air. BAFFLE PLATE: The baffle plate place in the fire hole is designed to direct the secondary air down towards the fired bed in order to mix thoroughly with the hot gases and flames. FUSIBLE PLUGS: Fusible plugs are screwed into the fire box crown. They are of brass and have a lead cure. If the water level in the boiler drop and uncovers the fire box crown, the lead melt allowing steam to escape into the fire box. This warns the engine men and help to deaden the fire. Both injectors should be put off immediately if this occurs and steps taken to remove or deaden the fire. SUPERHEATER: The super heater consists of super heater header and super heater elements. Steam from the main steam pipe arrives at the saturated steam chamber of the super heater header and is fed into the super heater element. Super heated steam arrives back at the super heater chamber of the super heater header and is fed into the steam pipe to the cylinder. Super heated steam is more expensive. ENERGY SAVING DEVICES OF THE BOILER Economizers: Transfer a portion of the heat in the stack gases to water being fed to the boiler. It is a heat exchanger installed in the exhaust stack that pre-heats the boiler feed water. AIR PRE HEATER: Transfer heat from hot stack gas to air that is to be mixed with fuel for combustion this device saves energy by increasing the temperature of the mixture of fuel and air prior to combustion, so more of the heat of combustion is available to heat water. TURBULATORS: Twisted pieces of metal inserted in the tubes of fire tub boilers, causes hot gases to travel more slowly and with more turbulence, resulting in better heat transfer to the water. OXYGEN TRIM CONTROLS: Measure stack gas oxygen concentration and automatically adjust the inlet air at the burner for optimum efficiency. . 1 ORCHARD EQUIPMENT Orchard equipments refer to the various machines (simple and complex) used on an orchard. Some of the machines include: pruners, sprayers, weeders, dusters, etc. The selection of choice of any of these machines is dependent on the nature of work to be carried out at that material time. PRUNERS – Also known as pruning shears or secateurs are a type of scissors for cu tting off hard branches of trees and shrubs. They are strong enough to prune hard branches of trees and shrubs sometimes up to two centimeters thick. SPRAYERS: A sprayer is a piece of equipment that has spray nozzle to apply herbicides and fertilizers to agricultural crops. Sprayers range in sizes from man-portable units to trailed types that are connected to a tractor or other self propelled units. There are various types of sprayers which include knap sack, foot, garden, Hand compression, power, stirrup, self-propelled crop sprayer, trailed crop sprayer, etc. COMPONENTS OF SPRAYING EQUIPMENT 1. TANK: The tank is a unit which holds chemicals, and comes in many different shapes and sizes. 2. PUMP: The pump creates pressure that forces the chemical to the nozzles. 3. CONTROL VALVE: The control valve controls or maintains pressure and turn off the sprayer. 4. NOZZLE TIP: The nozzle tip controls application rate and produce the correct size droplets. 5. FILTER: The filter is a unit behind the nozzle tip to reduce entrance or passage of dirty particles and blockage into the system. TYPES OF SPRAYING EQUIPMENTS 1. ULTRA-LOW VOLUME (ULV) SPRAYERS: ULV equipment is designed to produce very small droplets, thus ensuring even coverage with low volumes. The equipment is based on aerosol, airshear or rotary nozzle techniques. The ultra low volume machines use large volumes of air at low pressures to transform liquid into droplets that are dispersed into the atmosphere. Ultra low volume machines are used for applying pesticides, herbicides, fungicides, sterilizers and disinfectants among other chemicals. The ultra low volume machine consists of a blower, a formulation holding tank and a pump. The blower creates a low pressure area and forces air through the nozzles of the machine. Air pressure can be controlled by adjusting the engine speed. The nozzles of the machines have a very specific shape, which causes a swiring motion of the air stream. The motion is achieved by means of several agitationary fins that forces the air to rotate. The formulation is delivered to the air by means of a supply tube that is situated in the centre of the nozzles. The motion of the airshears the liquid formulation into very small droplets and then disperses it into the atmosphere. Advantages 1. The chemicals dispersed in this type of machine are more concentrated than the chemicals used in other spraying equipments, which increase the killing efficiency. 2. There is lower risk of injury due to low pressure application. The only disadvantage it has is that it requires long application times and higher technical skills. 2. KNAPSACK PRAYERS: The knapsack sprayer is a back mounted equipment used by farmers. The tank of a knapsack sprayer is not pressurized and made of grass, or galvanized steel. The pump may be fitted into or outside the tank and sucks the liquid from the tank and expels it through the discharge line. DUSTERS: Dusters usually refer to an aircraft used for dusting or spraying large farms with pesticides, though other types of dusters are also employed. Aerial spraying and dusting permits prompt coverage of large areas at the moment when application of pesticides is most effective and avoid the need for wheeled vehicles that might damage crops. COMPONENT PARTS OF A DUSTER: 1. HOPPER – For storing the chemicals in dust form 2. AGITATOR – An agitator is used to keep the dust moving freely within the hopper and prevent caking. 3. Metering mechanism- which is usually an adjustable orifice that allows the rate of discharge to be varied. 4. Delivery blower – which creates an airstream that is used to carry the powder to the target? The major difference between dusters and sprayers is that a sprayer is a machine that applies fluid chemicals to crops in liquid form while a duster is a machine that also applies fluid chemicals but in powdered form. WEEDERS: Weeders refers to the various equipments used to ease the task of removing weeds from orchards or gardens. Very common weeders include the fulcrum weeders, the Cape Cod weeders, and the cracle weeder. These weeders come in two styles: short handled weeders and long handled weeders. Short handled weeders are preferred for small gardens with small plants while long handled weeders are for bigger gardens that have bigger weeds. 3. 0. SORTING AND GRADING OF HORT. CROPS Sorting separates into groups different physical properties while grading separates into groups with different quality characteristics. Sorting and grading are usually the last separating operations before processing or displaying crops for sale. It should however be noted that damages at the stages of sorting and grading are likely to result in substantial economics loss. REASONS FOR SORTING AND GRADING OF HORT. CROPS Sorting and grading of Horticultural crops controls the effectiveness of the subsequent operations because; 1. Sorted and graded products are better suited to mechanical operations such as peeling, blending , etc e. g. use of caustic soda or boiling water with vegetables which helps flavor. 2. Sorting and grading is necessary in processes which heat transfer is critical e. g. sterilization. 3. Sorting and grading is advantageous in processes in which uniformity of heat transfer is desirable e. g. dehydration. 4. Sorting and grading of crops gives better control weights filled with standard scale container. . Sorted and graded products fare more attractive in consumer use, and allows the sizing of uniformly catering packs like packets of biscuits. Grading and quality separation of Horticultural crops depends on an overall assessment of those properties of the crops which affect its acceptance as a food or as a working substance for the food processor. Grading factors may be grouped un der the following: size and shape, maturity (e. g. freshness of eggs, ripeness in fruits, aging in meat), texture (e. g hardness, crispness in corn flakes) and flavor and aroma. GRADING MACHINERY Grading for size and quality is an essential preliminary to marketing of fruits and vegetables grown on commercial holdings, and many types of machines are available to assist this work. Some are cheap and simple sizing or weighing machines for grading produce which has been sorted for quality before hand. Others are complex and expensive machines which incorporate devices to facilitate sorting for quality, accurate sizing mechanisms and bins to facilitate packing. Grading machinery may be grouped broadly into those which grade by diameter and those which grade by weight. Machines which grade3 by diameter very greatly. Some size in only one or two directions, while others rotate the produce and thereby achieve a more accurate sizing. In general, machines that grade by diameter tend to have higher output, or are rather less expensive for given output then those which grade by Weight. On the other hand, a good weight grader has many advantages. It can be used for any shape, is easily adjustable and can be used for crops that are easily blemished. Grading by weight can also be more accurate than grading by diameter, though good diameter type graders are usually accurate enough for practical purposes. Good graders do little damage to apples, most of the bruising that does occur being caused when the fruit roots into the receiving bin. This is usually negligible compared with damage incurred in picking, and getting fruit to the grader. Output of graders varies widely according to the number and ability of the operators, as well as according to the machines and auxiliary equipment employed. Some graders are equipped with automatic box-tipping devices for loading. The graders in large-scale apple-packing stations are often fed by first immersing the boxes in water and then handling the fruit on to the drier by floatation. Outputs on such high-speed machines are frequently limited by the speed of packing. No one grading machine has all the advantages, so choice of a grader requires careful consideration of the most important needs for the conditions in which it is to be used. It is not possible to give an adequate description of any individual machine but below is a brief description of some of the grading machines: 1. SIZE GRADERS: This operates in two ways as follows; a. Produce falls through a circular hole of fixed size. In machines of this type the sizing board has a number of rows of holes of different sizes , and the crop is carried along by means of a series of wooden laths operated by a crank mechanism. The effect is to move the produce, without pushing or rolling it, to successively larger holes, until it falls through. b. As produce moves along conveyor, size of opening increases. Graders with mechanisms of this type are common, and include apple graders, in which the fruit is rapidly rolled along by a soft rubber belt, while leaning against a rubber barrier set at a gradually increasing distance from the belt, and machines with diverging rubber belts. . WEIGHT GRADERS: In weight graders, each fruit rests in an individual hinged cup, and for much of the journey along the conveyor the cup and fruit are supported in an upright position by a fixed guide rail. At suitable intervals, however, the support is provided by an adjustable lever-type weighing device. When the moment exerted by fruit and c up is sufficient, the cup tips, and deposits the fruit into its appropriate bin. 5. 0 MECHANICAL HARVESTING OF HORTICULTURAL FRUITS HARVESTING: Is the process of gathering mature crops or fruits from the fields. Harvesting marks the end of the growing cycle for a particular crop, and the harvest is the focus of a growing season. It is the most labour intensive activity of the growing season. Mechanical harvesting equipment tends to be designed mainly for fruits which are to be processed rather than those for fresh market. The main types of equipment used are combing devices and vibrators, Black currant harvester with shakers, as well as redcurrant harvesters with similar shaker units for grapes. Also available are slider cranks, tree shakers which make use of catching and collecting devices mostly applicable for olives. IMPORTANCE OF TIME OF HARVESITN OF HORTICULTURAL CROPS 1. It reduces wastage of crop produce since most fruits tend to rot when not harvested in time. 2. It gives the farmer more quality yield. When fruits in particular are harvested before they are fully ripe, they tend to be sour. 3. Timely harvesting of leafy vegetables gives room to greater yield as the cut away leaves give room for more to shoot out. COMPONENTS PARTS OF A MECHANICAL FRUIT HARVESTER 1. An impactor for dislodging fruits from a fruit-bearing tree limb mounted on a positioning arm. The arm moves up, down, forward, backward and twists. 2. A collecting conveyor for catching and conveying the dislodged fruits. The conveyor is supported by a frame and is comprised of series of supporters covered by a catching surface having an energy-absorbing flexible material. 3. A transfer conveyor which is supported by a frame and is placed below the outlet of the collecting conveyor. It receives fruits from the collecting conveyor. 4. A collecting Bin which is place below the outlet of the trans conveyor in which harvested fruits are deposited.
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