Peter and Harvey have ambitious plans to grow the business Essay

Peter and Harvey have ambitious plans to grow the business - Essay Example This research will begin with the statement that in this age, competitiveness is witnessed in each and every segment. As a result, developing a dominant position is extremely difficult in the market among other rival players. However, it might be possible only if the entrepreneurs desire to maintain a good relationship with its clients or customers. This is because; it is the relationship marketing that helps a new entrant (SPSL) to enhance its image and popularity in the market that may enhance its portfolio and reliability. Moreover, relationship marketing also acts as a weapon to enhance the profitability and productivity of the organization thereby amplifying its equity and market share to a significant extent as compared to others. Similarly, in case of SPSL, Peter and Harvey offered high concentration over relationship marketing that may amplify its total sale and revenues. This strategy might amplify the level of sustainability in the market among other existing rivals. In thi s age, awareness is an essential requirement of any business organization.   Only then, it might improve its image and demand of product lines within the minds of the customers that may amplify its reputation and profitability. However, awareness might be enhanced only with the help of promotion. Promotion might take place through the personal selling process. It is processed in which, an organization or entrepreneur recruits a wide range of sales forces or sales persons so as to sell its products.

Managing for the future Essay Example | Topics and Well Written Essays - 3000 words

Managing for the future - Essay Example This fact can be analyzed by looking at the magazines who printed its success. "FT Global 500" by Financial Times, "The World's 2000 Biggest Public Companies" by Forbes magazine and by the Dow Jones Sustainability Indexes (Developing Telecoms | China Mobile | Sponsors Directory, 2012). According to its official website, Limited China Mobile Limited(2012), it has more than 34 subsidiaries like China Mobile Communication Company Limited (â€Å"CMC") , ZONG, China Mobile Group Guangdong Company Limited ("Guangdong Mobile"), Jiangsu Mobile and Hong Kong Mobile etc. The board of directors of China Mobile Ltd consists of Executive Directors and Independent Non-Executive Directors. The executive directors are seven in number whereas the Independent Non-Executive Directors are three in number (China Mobile Limited - About China Mobile > Board of Directors, 2012). 1.1 Milestones from 2006-2012 2006 marks some of the most important changes which came in the company. China Mobile Limited was f ormerly named as China Mobile (Hong Kong) Limited. The change in the company’s name came in the year 2006. This year also marks the privatization of China Resources Peoples Telephone Company Ltd. The privatization benefitted the company allot and gave a boost to its annual profits. In 2006, News Corp. and STAR Group Ltd. formed wireless media tactical association with China Mobile Ltd (China Mobile Limited - About China Mobile > Milestones, 2012). According to the company’s official website the year 2009 marks a share subscription agreement with the company Far EasTone. This increased the annual company profit (China Mobile Limited - About China Mobile > Milestones, 2012). Guangdong Mobile and SPD bank signed a share subscription agreement in the year 2010. This agreement increased the interest of both the subsidiaries of the company. It further strengthened the company’s e-commerce and mobile finance businesses (China Mobile Limited - About China Mobile > Miles tones, 2012). 2012 marks a lot of success news for the company. The company got a lot of awards for its performance and expansion. "Grand Award Winners -- Investor Relations" and three "iNova Awards 2012" serve as the most honorable achievements of the company. Moreover, the company is nominated for the Top favorite China Corporate Brand voted by China Consumer" and it was included in the Financial Times magazine again. It is the company which keeps it head high by coming up for the Millward Brown and Financial Times' "BRANDZâ„ ¢ Top 100" list for the seventh year uninterruptedly (China Mobile Limited - Media Centre > News Highlights, 2012). 1.2 What about the future? From the year 2006-2012, the company has been the most successful company in the wireless mobile services business. It has seen many success stories and good times. It is important for the company to maintain its reputation and image for the future as well. Be it Apple Inc. or Samsung, all the companies have been at the top because they keep on inventing new things for the future. They try to plan for the future and implement the strategies accordingly. China Mobile Limited has a lot of competition in the age of wireless technology. To remain the best it has to innovate and plan for its future. A company’s success lies in the people who work for it. The company’s biggest assets are people (Zolezzi, 2004. pp.41). 1.3 Management, Marketing and Understanding the Key Stakeholders Marketing is a tool to sell the product or service. It

Physics Project Essay Example for Free

Physics Project Essay Eyes are organs that detect light, and convert it to electro-chemical impulses in neurons. The simplest photoreceptors in conscious vision connect light to movement. In higher organisms the eye is a complex optical system which collects light from the surrounding environment; regulates its intensity through a diaphragm; focuses it through an adjustable assembly of lenses to form an image; converts this image into a set of electrical signals; and transmits these signals to the brain, through complex neural pathways that connect the eye, via the optic nerve, to the visual cortex and other areas of the brain. Eyes with resolving power have come in ten fundamentally different forms, and 96% of animal species possess a complex optical system.[1] Image-resolving eyes are present in molluscs, chordates and arthropods. [2] The simplest eyes, such as those in microorganisms, do nothing but detect whether the surroundings are light or dark, which is sufficient for the entrainment of circadian rhythms. From more complex eyes, retinal photosensitive ganglion cells send signals along the retinohypothalamic tract to the suprachiasmatic nuclei to effect circadian adjustment. Contents[hide] * 1 Overview * 2 Evolution * 3 Types of eye * 3.1 Normal eyes * 3.2 Pit eyes * 3.2.1 Spherical lensed eye * 3.2.2 Multiple lenses * 3.2.3 Refractive cornea * 3.2.4 Reflector eyes * 3.3 Compound eyes * 3.3.1 Apposition eyes * 3.3.2 Superposition eyes * 3.3.3 Parabolic superposition * 3.3.4 Other * 3.3.5 Nutrients of the eye * 4 Relationship to life requirements * 5 Visual acuity * 6 Perception of colours * 7 Rods and cones * 8 Pigmentation * 9 See also * 10 References * 10.1 Notes * 10.2 Bibliography * 11 External links| [edit] Overview Eye of the wisent, the European bison Complex eyes can distinguish shapes and colors. The visual fields of many organisms, especially predators, involve large areas of binocular vision to improve depth perception; in other organisms, eyes are located so as to maximize the field of view, such as in rabbits and horses, which have monocular vision. The first proto-eyes evolved among animals 600 million years ago, about the time of the Cambrian explosion.[3] The last common ancestor of animals possessed the biochemical toolkit necessary for vision, and more advanced eyes have evolved in 96% of animal species in six of the thirty-plus[4] main phyla.[1] In most vertebrates and some molluscs, the eye works by allowing light to enter and project onto a light-sensitive panel of cells, known as the retina, at the rear of the eye. The cone cells (for color) and the rod cells (for low-light contrasts) in the retina detect and convert light into neural signals for vision. The visual signals are then transmitted to the brain via the optic nerve. Such eyes are typically roughly spherical, filled with a transparent gel-like substance called the vitreous humour, with a focusing lens and often an iris; the relaxing or tightening of the muscles around the iris change the size of the pupil, thereby regulating the amount of light that enters the eye,[5] and reducing aberrations when there is enough light.[6] The eyes of most cephalopods, fish, amphibians and snakes have fixed lens shapes, and focusing vision is achieved by telescoping the lens—similar to how a camera focuses.[7] Compound eyes are found among the arthropods and are composed of many simple facets which, depending on the details of anatomy, may give either a single pixelated image or multiple images, per eye. Each sensor has its own lens and photosensitive cell(s). Some eyes have up to 28,000 such sensors, which are arranged hexagonally, and which can give a full 360-degree field of visio n. Compound eyes are very sensitive to motion. Some arthropods, including many Strepsiptera, have compound eyes of only a few facets, each with a retina capable of creating an image, creating vision. With each eye viewing a different thing, a fused image from all the eyes is produced in the brain, providing very different, high-resolution images. Possessing detailed hyperspectral color vision, the Mantis shrimp has been reported to have the worlds most complex color vision system.[8] Trilobites, which are now extinct, had unique compound eyes. They used clear calcite crystals to form the lenses of their eyes. In this, they differ from most other arthropods, which have soft eyes. The number of lenses in such an eye varied, however: some trilobites had only one, and some had thousands of lenses in one eye. In contrast to compound eyes, simple eyes are those that have a single lens. For example, jumping spiders have a large pair of simple eyes with a narrow field of view, supported by an array of other, smaller eyes for peripheral vision. Some insect larvae, like caterpillars, have a different type of simple eye (stemmata) which gives a rough image. Some of the simplest eyes, called ocelli, can be found in animals like some of the snails, which cannot actually see in the normal sense. They do have photosensitive cells, but no lens and no other means of projecting an image onto these cells. They can distinguish between light and dark, but no more. This enables snails to keep out of direct sunlight. In organisms dwelling near deep-sea vents, compound eyes have been secondarily simplified and adapted to spot the infra-red light produced by the hot vents–in this way the bearers can spot hot springs and avoid being boiled alive.[9] [edit] Evolution Main article: Evolution of the eye Evolution of the eye Photoreception is phylogenetically very old, with various theories of phylogenesis.[10] The common origin (monophyly) of all animal eyes is now widely accepted as fact. This is based upon the shared anatomical and genetic features of all eyes; that is, all modern eyes, varied as they are, have their origins in a proto-eye believed to have evolved some 540 million years ago.[11][12][13] The majority of the advancements in early eyes are believed to have taken only a few million years to develop, since the first predator to gain true imaging would have touched off an arms race.[14] Prey animals and competing predators alike would be at a distinct disadvantage without such capabilities and would be less likely to survive and reproduce. Hence multiple eye types and subtypes developed in parallel. Eyes in various animals show adaption to their requirements. For example, birds of prey have much greater visual acuity than humans, and some can see ultraviolet light. The different forms of ey e in, for example, vertebrates and mollusks are often cited as examples of parallel evolution, despite their distant common ancestry. The very earliest eyes, called eyespots, were simple patches of photoreceptor protein in unicellular animals. In multicellular beings, multicellular eyespots evolved, physically similar to the receptor patches for taste and smell. These eyespots could only sense ambient brightness: they could distinguish light and dark, but not the direction of the lightsource.[15] Through gradual change, as the eyespot depressed into a shallow cup shape, the ability to slightly discriminate directional brightness was achieved by using the angle at which the light hit certain cells to identify the source. The pit deepened over time, the opening diminished in size, and the number of photoreceptor cells increased, forming an effective pinhole camera that was capable of dimly distinguishing shapes.[16] The thin overgrowth of transparent cells over the eyes aperture, originally formed to prevent damage to the eyespot, allowed the segregated contents of the eye chamber to specialize into a transparent humour that optimized color filtering, blocked harmful radiation, improved the eyes refractive index, and allowed functionality outside of water. The transparent protective cells eventually split into two layers, with circulatory fluid in between that allowed wider viewing angles and greater imaging resolution, and the thickness of the transparent layer gradually increased, in most species with the transparent crystallin protein.[17] The gap between tissue layers naturally formed a bioconvex shape, an optimally ideal structure for a normal refractive index. Independently, a transparent layer and a nontransparent layer split forward from the lens: the cornea and iris. Separation of the forward layer again formed a humour, the aqueous humour. This increased refractive power and again eased circulatory problems. Formation of a nontransparent ring allowed more blood vessels, more circulation, and larger eye sizes.[17] [edit] Types of eye There are ten different eye layouts—indeed every way of capturing an image known to man, with the exceptions of zoom and Fresnel lenses. Eye types can be categorized into simple eyes, with one concave photoreceptive surface, and compound eyes, which comprise a number of individual lenses laid out on a convex surface.[1] Note that simple does not imply a reduced level of complexity or acuity. Indeed, any eye type can be adapted for almost any behavior or environment. The only limitations specific to eye types are that of resolution—the physics of compound eyes prevents them from achieving a resolution better than 1Â °. Also, superposition eyes can achieve greater sensitivity than apposition eyes, so are better suited to dark-dwelling creatures.[1] Eyes also fall into two groups on the basis of their photoreceptors cellular construction, with the photoreceptor cells either being cilliated (as in the vertebrates) or rhabdomeric. These two groups are not monophyletic; the cnidaria also possess cilliated cells, [18] and some annelids possess both.[19] [edit] Normal eyes Human eyes are examples of normal eyes Simple eyes are rather ubiquitous, and lens-bearing eyes have evolved at least seven times in vertebrates, cephalopods, annelids, crustacea and cubozoa.[20] [edit Pit eyes Pit eyes, also known as stemma, are eye-spots which may be set into a pit to reduce the angles of light that enters and affects the eyespot, to allow the organism to deduce the angle of incoming light.[1] Found in about 85% of phyla, these basic forms were probably the precursors to more advanced types of simple eye. They are small, comprising up to about 100 cells covering about 100 Â µm.[1] The directionality can be improved by reducing the size of the aperture, by incorporating a reflective layer behind the receptor cells, or by filling the pit with a refractile material.[1] [edit] Spherical lensed eye The resolution of pit eyes can be greatly improved by incorporating a material with a higher refractive index to form a lens, which may greatly reduce the blur radius encountered—hence increasing the resolution obtainable.[1] The most basic form, still seen in some gastropods and annelids, consists of a lens of one refractive index. A far sharper image can be obtained using materials with a high refractive index, decreasing to the edges; this decreases the focal length and thus allows a sharp image to form on the retina.[1] This also allows a larger aperture for a given sharpness of image, allowing more light to enter the lens; and a flatter lens, reducing spherical aberration.[1] Such an inhomogeneous lens is necessary in order for the focal length to drop from about 4 times the lens radius, to 2.5 radii.[1] Heterogeneous eyes have evolved at least eight times: four or more times in gastropods, once in the copepods, once in the annelids and once in the cephalopods.[1] No aquatic organisms possess homogeneous lenses; presumably the evolutionary pressure for a heterogeneous lens is great enough for this stage to be quickly outgrown.[1] This eye creates an image that is sharp enough that motion of the eye can cause significant blurring. To minimize the effect of eye motion while the animal moves, most such eyes have stabilizing eye muscles.[1] The ocelli of insects bear a simple lens, but their focal point always lies behind the retina; consequently they can never form a sharp image. This capitulates the function of the eye. Ocelli (pit-type eyes of arthropods) blur the image across the whole retina, and are consequently excellent at responding to rapid changes in light intensity across the whole visual field; this fast response is further accelerated by the large nerve bundles which rush the information to the brain.[21] Focusing the image would also cause the suns image to be focused on a few receptors, with the possibility of damage under the intense light; shielding the receptors would block out some light and thus reduce their sensitivity.[21] This fast response has led to suggestions that the ocelli of insects are used mainly in flight, because they can be used to detect sudden changes in which way is up (because light, especially UV light which is absorbed by vegetation, usually comes from above).[21] [edit] Multiple lenses Some marine organisms bear more than one lens; for instance the copepod Pontella has three. The outer has a parabolic surface, countering the effects of spherical aberration while allowing a sharp image to be formed. Another copepod, Copilias eyes have two lenses, arranged like those in a telescope.[1] Such arrangements are rare and poorly understood, but represent an interesting alternative construction. An interesting use of multiple lenses is seen in some hunters such as eagles and jumping spiders, which have a refractive cornea (discussed next): these have a negative lens, enlarging the observed image by up to 50% over the receptor cells, thus increasing their optical resolution.[1] [edit] Refractive cornea In the eyes of most mammals, birds, reptiles, and most other terrestrial vertebrates (along with spiders and some insect larvae) the vitreous fluid has a higher refractive index than the air, relieving the lens of the function of reducing the focal length. This has freed it up for fine adjustments of focus, allowing a very high resolution to be obtained.[1] As with spherical lenses, the problem of spherical aberration caused by the lens can be countered either by using an inhomogeneous lens material, or by flattening the lens.[1] Flattening the lens has a disadvantage; the quality of vision is diminished away from the main line of focus, meaning that animals requiring all-round vision are detrimented. Such animals often display an inhomogeneous lens instead.[1] As mentioned above, a refractive cornea is only useful out of water; in water, there is no difference in refractive index between the vitreous fluid and the surrounding water. Hence creatures which have returned to the waterâ €”penguins and seals, for example—lose their refractive cornea and return to lens-based vision. An alternative solution, borne by some divers, is to have a very strong cornea.[1] [edit] Reflector eyes An alternative to a lens is to line the inside of the eye with mirrors, and reflect the image to focus at a central point.[1] The nature of these eyes means that if one were to peer into the pupil of an eye, one would see the same image that the organism would see, reflected back out.[1] Many small organisms such as rotifers, copeopods and platyhelminths use such organs, but these are too small to produce usable images.[1] Some larger organisms, such as scallops, also use reflector eyes. The scallop Pecten has up to 100 millimeter-scale reflector eyes fringing the edge of its shell. It detects moving objects as they pass successive lenses.[1] There is at least one vertebrate, the spookfish, whose eyes include reflective optics for focusing of light. Each of the two eyes of a spookfish collects light from both above and below; the light coming from above is focused by a lens, while that coming from below, by a curved mirror composed of many layers of small reflective plates made of g uanine crystals.[22] [edit] Compound eyes An image of a house fly compound eye surface by using Scanning Electron Microscope Anatomy of the compound eye of an insect Arthropods such as this carpenter bee have compound eyes A compound eye may consist of thousands of individual photoreceptor units or ommatidia (ommatidium, singular). The image perceived is a combination of inputs from the numerous ommatidia (individual eye units), which are located on a convex surface, thus pointing in slightly different directions. Compared with simple eyes, compound eyes possess a very large view angle, and can detect fast movement and, in some cases, the polarization of light.[23] Because the individual lenses are so small, the effects of diffraction impose a limit on the possible resolution that can be obtained. This can only be countered by increasing lens size and number. To see with a resolution comparable to our simple eyes, humans would require compound eyes which would each reach the size of their head. Compound eyes fall into two groups: apposition eyes, which form multiple inverted images, and superposition eyes, which form a single erect image.[24] Compound eyes are common in arthropods, and are also present in annelids and some bivalved molluscs.[25] Compound eyes, in arthropods at least, grow at their margins by the addition of new ommatidia.[26] Structure of the ommatidia of apposition compound eyes [edit] Apposition eyes Apposition eyes are the most common form of eye, and are presumably the ancestral form of compound eye. They are found in all arthropod groups, although they may have evolved more than once within this phylum.[1] Some annelids and bivalves also have apposition eyes. They are also possessed by Limulus, the horseshoe crab, and there are suggestions that other chelicerates developed their simple eyes by reduction from a compound starting point.[1] (Some caterpillars appear to have evolved compound eyes from simple eyes in the opposite fashion.) Apposition eyes work by gathering a number of images, one from each eye, and combining them in the brain, with each eye typically contributing a single point of information. The typical apposition eye has a lens focusing light from one direction on the rhabdom, while light from other directions is absorbed by the dark wall of the ommatidium. In the other kind of apposition eye, found in the Strepsiptera, lenses are not fused to one another, and each forms an entire image; these images are combined in the brain. This is called the schizochroal compound eye or the neural superposition eye. Because images are combined additively, this arrangement allows vision under lower light levels.[1] [edit] Superposition eyes The second type is named the superposition eye. The superposition eye is divided into three types; the refracting, the reflecting and the parabolic superposition eye. The refracting superposition eye has a gap between the lens and the rhabdom, and no side wall. Each lens takes light at an angle to its axis and reflects it to the same angle on the other side. The result is an image at half the radius of the eye, which is where the tips of the rhabdoms are. This kind is used mostly by nocturnal insects. In the parabolic superposition compound eye type, seen in arthropods such as mayflies, the parabolic surfaces of the inside of each facet focus light from a reflector to a sensor array. Long-bodied decapod crustaceans such as shrimp, prawns, crayfish and lobsters are alone in having reflecting superposition eyes, which also have a transparent gap but use corner mirrors instead of lenses. [edit] Parabolic superposition This eye type functions by refracting light, then using a parabolic mirror to focus the image; it combines features of superposition and apposition eyes.[9] [edit] Other The compound eyes of a dragonfly Good fliers like flies or honey bees, or prey-catching insects like praying mantis or dragonflies, have specialized zones of ommatidia organized into a fovea area which gives acute vision. In the acute zone the eyes are flattened and the facets larger. The flattening allows more ommatidia to receive light from a spot and therefore higher resolution. There are some exceptions from the types mentioned above. Some insects have a so-called single lens compound eye, a transitional type which is something between a superposition type of the multi-lens compound eye and the single lens eye found in animals with simple eyes. Then there is the mysid shrimp Dioptromysis paucispinosa. The shrimp has an eye of the refracting superposition type, in the rear behind this in each eye there is a single large facet that is three times in diameter the others in the eye and behind this is an enlarged crystalline cone. This projects an upright image on a specialized retina. The resulting eye is a mixture of a simple eye within a compound eye. Another version is the pseudofaceted eye, as seen in Scutigera. This type of eye consists of a cluster of numerous ocelli on each side of the head, organized in a way that resembles a true compound eye. The body of Ophiocoma wendtii, a type of brittle star, is covered with ommatidia, turning its whole skin into a compound eye. The same is true of many chitons. [edit] Nutrients of the eye The ciliary body is triangular in horizontal section and is coated by a double layer, the ciliary epithelium. The inner layer is transparent and covers the vitreous body, and is continuous from the neural tissue of the retina. The outer layer is highly pigmented, continuous with the retinal pigment epithelium, and constitutes the cells of the dilator muscle. The vitreous is the transparent, colorless, gelatinous mass that fills the space between the lens of the eye and the retina lining the back of the eye.[27] It is produced by certain retinal cells. It is of rather similar composition to the cornea, but contains very few cells (mostly phagocytes which remove unwanted cellular debris in the visual field, as well as the hyalocytes of Balazs of the surface of the vitreous, which reprocess the hyaluronic acid), no blood vessels, and 98-99% of its volume is water (as opposed to 75% in the cornea) with salts, sugars, vitrosin (a type of collagen), a network of collagen type II fibers with the mucopolysaccharide hyaluronic acid, and also a wide array of proteins in micro amounts. Amazingly, with so little solid matter, it tautly holds the eye. [edit]Relationship to life requirements Eyes are generally adapted to the environment and life requirements of the organism which bears them. For instance, the distribution of photoreceptors tends to match the area in which the highest acuity is required, with horizon-scanning organisms, such as those that live on the African plains, having a horizontal line of high-density ganglia, while tree-dwelling creatures which require good all-round vision tend to have a symmetrical distribution of ganglia, with acuity decreasing outwards from the centre. Of course, for most eye types, it is impossible to diverge from a spherical form, so only the density of optical receptors can be altered. In organisms with compound eyes, it is the number of ommatidia rather than ganglia that reflects the region of highest data acquisition.[1]:23-4 Optical superposition eyes are constrained to a spherical shape, but other forms of compound eyes may deform to a shape where more ommatidia are aligned to, say, the horizon, without altering the size or density of individual ommatidia.[28] Eyes of horizon-scanning organisms have stalks so they can be easily aligned to the horizon when this is inclined, for example if the animal is on a slope.[29] An extension of this concept is that the eyes of predators typically have a zone of very acute vision at their centre, to assist in the identification of prey.[28] In deep water organisms, it may not be the centre of the eye that is enlarged. The hyperiid amphipods are deep water animals that feed on organisms above them. Their eyes are almost divided into two, with the upper region thought to be involved in detecting the silhouettes of potential prey—or predators—against the faint light of the sky above. Accordingly, deeper water hyperiids, where the light against which the silhouettes must be compared is dimmer, have larger upper-eyes, and may lose the lower portion of their eyes altogether.[28] Depth perception can be enhanced by having eyes which are enlarged in one direction; distorting the eye slightly allows the distance to the object to be estimated with a high degree of accuracy.[9] Acuity is higher among male organisms that mate in mid-air, as they need to be able to spot and assess potential mates against a very large backdrop.[28] On the other hand, the eyes of organisms which operate in low light levels, such as around dawn and dusk or in deep water, tend to be larger to increase the amount of light that can be captured.[28] It is not only the shape of the eye that may be affected by lifestyle. Eyes can be the most visible parts of organisms, and this can act as a pressure on organisms to have more transparent eyes at the cost of function.[28] Eyes may be mounted on stalks to provide better all-round vision, by lifting them above an organisms carapace; this also allows them to track predators or prey without moving the head.[9] [edit] Visual acuity A hawks eye Visual acuity, or resolving power, is the ability to distinguish fine detail and is the property of cones.[30] It is often measured in cycles per degree (CPD), which measures an angular resolution, or how much an eye can differentiate one object from another in terms of visual angles. Resolution in CPD can be measured by bar charts of different numbers of white/black stripe cycles. For example, if each pattern is 1.75 cm wide and is placed at 1 m distance from the eye, it will subtend an angle of 1 degree, so the number of white/black bar pairs on the pattern will be a measure of the cycles per degree of that pattern. The highest such number that the eye can resolve as stripes, or distinguish from a gray block, is then the measurement of visual acuity of the eye. For a human eye with excellent acuity, the maximum theoretical resolution is 50 CPD[31] (1.2 arcminute per line pair, or a 0.35 mm line pair, at 1 m). A rat can resolve only about 1 to 2 CPD.[32] A horse has higher acuity through most of the visual field of its eyes than a human has, but does not match the high acuity of the human eyes central fovea region. Spherical aberration limits the resolution of a 7 mm pupil to about 3 arcminutes per line pair. At a pupil diameter of 3 mm, the spherical aberration is greatly reduced, resulting in an improved resolution of approximately 1.7 arcminutes per line pair.[33] A resolution of 2 arcminutes per line pair, equivalent to a 1 arcminute gap in an optotype, corresponds to 20/20 (normal vision) in humans. [edit] Perception of colours Colour vision is the faculty of the organism to distinguish lights of different spectral qualities.[34] All organisms are restricted to a small range of electromagnetic spectrum; this varies from creature to creature, but is mainly between 400 and 700 nm.[35] This is a rather small section of the electromagnetic spectrum, probably reflecting the submarine evolution of the organ: water blocks out all but two small windows of the EM spectrum, and there has been no evolutionary pressure among land animals to broaden this range.[36] The most sensitive pigment, rhodopsin, has a peak response at 500 nm.[37] Small changes to the genes coding for this protein can tweak the peak response by a few nm;[2] pigments in the lens can also filter incoming light, changing the peak response.[2] Many organisms are unable to discriminate between colours, seeing instead in shades of grey; color vision necessitates a range of pigment cells which are primarily sensitive to smaller ranges of the spectrum. In primates, geckos, and other organisms, these take the form of cone cells, from which the more sensitive rod cells evolved.[37] Even if organisms are physically capable of discriminating different colours, this does not necessarily mean that they can perceive the different colours; only with behavioural tests can this be deduced.[2] Most organisms with colour vision are able to detect ultraviolet light. This high energy light can be damaging to receptor cells. With a few exceptions (snakes, placental mammals), most organisms avoid these effects by having absorbent oil droplets around their cone cells. The alternative, developed by organisms that had lost these oil droplets in the course of evolution, is to make the lens impervious to UV light — this precludes the possibility of any UV light being detected, as it does not even reach the retina.[37] [edit] Rods and cones The retina contains two major types of light-sensitive photoreceptor cells used for vision: the rods and the cones. Rods cannot distinguish colours, but are responsible for low-light (scotopic) monochrome (black-and-white) vision; they work well in dim light as they contain a pigment, rhodopsin (visual purple), which is sensitive at low light intensity, but saturates at higher (photopic) intensities. Rods are distributed throughout the retina but there are none at the fovea and none at the blind spot. Rod density is greater in the peripheral retina than in the central retina. Cones are responsible for colour vision. They require brighter light to function than rods require. In humans, there are three types of cones, maximally sensitive to long-wavelength, medium-wavelength, and short-wavelength light (often referred to as red, green, and blue, respectively, though the sensitivity peaks are not actually at these colours). The colour seen is the combined effect of stimuli to, and responses from, these three types of cone cells. Cones are mostly concentrated in and near the fovea. Only a few are present at the sides of the retina. Objects are seen most sharply in focus when their images fall on the fovea, as when one looks at an object directly. Cone cells and rods are connected through intermediate cells in the retina to nerve fibres of the optic nerve. When rods and cones are stimulated by light, the nerves send off impulses through these fibres to the brain.[37] [edit] Pigmentation The pigment molecules used in the eye are various, but can be used to define the evolutionary distance between different groups, and can also be an aid in determining which are closely related – although problems of convergence do exist.[37] Opsins are the pigments involved in photoreception. Other pigments, such as melanin, are used to shield the photoreceptor cells from light leaking in from the sides. The opsin protein group evolved long before the last common ancestor of animals, and has continued to diversify since.[2] There are two types of opsin involved in vision; c-opsins, which are associated with ciliary-type photoreceptor cells, and r-opsins, associated with rhabdomeric photoreceptor cells.[38] The eyes of vertebrates usually contain cilliary cells with c-opsins, and (bilaterian) invertebrates have rhabdomeric cells in the eye with r-opsins. However, some ganglion cells of vertebrates express r-opsins, suggesting that their ancestors used this pigment in vision, an d that remnants survive in the eyes.[38] Likewise, c-opsins have been found to be expressed in the brain of some invertebrates. They may have been expressed in ciliary cells of larval eyes, which were subsequently resorbed into the brain on metamorphosis to the adult form.[38] C-opsins are also found in some derived bilaterian-invertebrate eyes, such as the pallial eyes of the bivalve molluscs; however, the lateral eyes (which were presumably the ancestral type for this group, if eyes evolved once there) always use r-opsins.[38] Cnidaria, which are an outgroup to the taxa mentioned above, express c-opsins but r-opsins are yet to be found in this group.[38] Incidentally, the melanin produced in the cnidaria is produced in the same fashion as that in vertebrates, suggesting the common descent of this pigment.[38]

Effects of Level of Nutrition on Milk Yield and Composition

Effects of Level of Nutrition on Milk Yield and Composition Effects of Level of Nutrition on Milk Yield and Composition of Cows Fed Natural Grazing and Offered Different Supplements, in South Kordofan, Sudan ABSTRACT: Three feed ingredients that were locally used as supplements and fed to dairy cattle were offered to three groups of dairy cows while one group was considered as control and left on the natural grazing only and another one was offered a ration formulated to meet maintenance and production requirements. Milk quantity and its composition were monitored for 40 days. The results showed that supplementation of cows with 1.5 kg of any feed ingredient resulted in increment of milk production compared with those left on the natural grazing alone. Supplementation with oil seed cakes or cotton seeds was better as supplements than sorghum grains in promoting milk production. The highest performance was achieved with the group was fed 1.0 kg of formulated ration. The milk yield increased linearly (p

education :: essays research papers

Educating our Youth The Authors that we read in class all had esteemed criticism when talking about our nations education system but the one essay that stood out the most for me was about our children being more interactive with the community. Robert Coles argues that our childred need to be more respectable towards elders and be more involved in the growth of the community.   Ã‚  Ã‚  Ã‚  Ã‚  Respectively I think that Mr. Coles makes a very convincing argument, and that when you break down all of the other arguments, everything pieces together under one major category. Bell Hooks argues that our schools are too large and that the students need to feel a sense of surrounding in order for them to be able to learn better, Ms. Meier has a convincing argument that standardization of our school just like the ones in Europe are needed, and Linda Darling-Hammond argues that there is unequal opportunity among our schools specifically dealing with racism distributed throughout our school system.   Ã‚  Ã‚  Ã‚  Ã‚  When you look at Bell Hook’s argument that our schools are too large and that the students that are going to school in the city are not getting the same education as the students in the suberb’s. This argument can directly tie into the fact that yes there defiantly needs to be a more teacher to student ratio, because in every statistical analysis of the school system the less students in a class, the more comfortable the student is in his surrounding and the easier it is for the student to learn. Basically this situation can be solved by involving the student in the school, and in the community better. Solving a situation like cutting classroom size down with flooding more money into schools isn’t going to solve the way that students learn. I believe that students learn by the influence of others around them, others like their parents, their role models, and fellow classmates.   Ã‚  Ã‚  Ã‚  Ã‚  I don’t fully agree with the fact that there is unequal opportunity among students of different race, or that there need to be a standardization among grades for students like there is in Europe. The problem here in America is that kids aren’t feeling the connection with their peers. Kids don’t have motivation to learn, they see that their parents are not tied to their lives and they don’t feel that connection with the community like they are supposed to.

Speech: Universal Health Care :: Papers Argumentative Medicine Essays

Speech: Universal Health Care Topic: Universal Health Care General Purpose: To persuade. Specific Purpose: To Persuade my audience that the United States needs to adopt universal health care. Central Idea: Americans current health care system is faulty and needs to be changed to Universal Health Care for all citizens. INTRODUCTION I. Have you ever went without health insurance between jobs, or while working part time or because you just couldn?t afford it? No having health insurance is a big risk in a time where medical costs are sky high, Prescription drug prices are outrageous and when your paying your family doctor $50 for a office visit. Fifty dollars represents a full 8 hours of work for many Americans. A. Health care reform is needed in America. Service for pay medical treatment leaves uninsured citizens going without health care, or seriously in debt. B. Today I want to tell you why adopting universal health care is the answer to the question of health care reform. II. I have had many negative encounters with the health care system. A. At one time because of being a part time student and employee, I could not get insurance though my parents, my work, or my school. I was not eligible for Medicaid, and found the cost of private insurance was completely out of my budget. 1. This was a bad mistake. I was born with neutropenia, a blood disease that affects the immune system I get sick very easily, and my body has a hard time fighting off any infections and trying to stay healthy without insurance soon became impossible B. Suddenly I found myself in serious debt from missing work, doctor?s office visits, and paying outrageous prescription costs. I am still paying off medical bills for lab work, and other tests and emergency room visits. III. Today I want to discuss the reasons why our current health care system is ineffective, the benefits of changing to universal health care, and we will also look at Hawaii?

Effect of racism from a functionalist’s point of view Essay

One of the most identifiable effects of racial discrimination in education and training is the negative impact it has on the performance of children at school. The failure to address the needs of minority children and those of migrant workers through, for example, combating racial stereotyping or through formulating school curricula that include modules on minority languages and cultures, can lead to school curricula which lack relevance for those children. As a result, children may lose interest and become bored at school which in turn increases the risk that children will drop out early or even fail to attend school at all. The failure to provide curricula adapted to the specific needs of the children of minorities and migrant workers can also lead to low literacy rates amongst these groups. Similarly, where a child does not have an adequate grasp of the official language, the failure to provide additional language classes in the official language and to provide classes in minority or migrant languages could have the effect of retarding the progress of those children through school. Another long-term effect of racial discrimination is that children learn to accept acts of racial discrimination as the norm. Such learnt behaviour can lead to the consolidation of racial discrimination within society as the norm, with children of minorities or migrants growing up and discriminating against the newest influx of migrants. Thus, a vicious cycle of discriminatory behaviour is produced which reinforces racially discriminatory behaviour. The forced segregation of children of minorities and migrant workers from other children can have serious negative effects on the capacity of these children to integrate with other children and into the society in general. In particular, segregation of children into schools for mentally handicapped children can severely retard the child’s progress through school and can affect his or her self-image. Education is arguably the basis of a functionalist’s beliefs, where children learn social skills and behaviours, these skills help build towards unity in society. Therefore racism is abhored in their beliefs.