Seedling Production Of Mud Crab Scylla Serrata Biology Essay

Seedling Production Of Mud Crab Scylla Serrata Biology Essay Seedling production of mud crab Scylla serrata has the potential to be an effective tool to support the demand of mud crab due depleted seed stock from the wild. Moreover, there is high consumer demand on the global production of mud crab Scylla serrata from 1999 to 2000. Generally, consumer for mud crab Scylla serrata is Chinese communities which particularly at China, Vietnam, Singapore, Taiwan, Hong Kong and also Malaysia (Liong, 1993). Further, Malaysia aquaculture only practices a growth out of mud crab until the marketable size. Malaysia is currently in progress to develop mud crab industry by not relying on seed stock from Thailand. The crab production is relatively small about 650 tonnes per year (Liong, 1992). In Malaysia, not many studies have been done on mud crab culture. Studies on the larvae culture by Jamari (1992) shows that the high mortality of the megalopa and crablet stages cause by cannibalism among the larvae. Several studies of rearing mud crab larvae had been reported in Indonesia (Marjono and Arifin ,1993), Philippine (Quinitio, 1997) ,Vietnam (Hoang, 1999) and Japan ( Hamasaki,2002 ) that shows the high percentage of survival rate were 3.2 % , 3.7 % ,24 % and 30%-40%. However, the survival rate is still low ranged from 1% to 30% from zoea to megalopa. Current status In Malaysia, the production of mud crab has been decreased begin 1995 to 2005 (625 tonnes to 162 tonnes). However, the production of mud crab in other countries such as Indonesia, Philippines and china were increased significantly. Recently, the market demand for mud crabs has exceeded wild harvest. Mostly, mud crabs were imported from India, Sri Lanka, Indonesia and Bangladesh. The present improvised status of mud crab stock in Malaysia is also compounded by other factor. These included a recent increasing interest in soft-shell and growth out mud crab framing .In addition, more conventional culture method were invented such as compact crab farming system for growth out mud crab. Further, this new breeding system has been widely implemented by Perlis state community under the Perlis State Economic Development Corporation. In addition, the most factors that contribute interest to the mud crab culture is due to high demand and fetches a good price compare to other crabs species such as blue crab (Callinectes sapidus). During this time, the price has increased from RM 10.00/kg in 2009 to RM 30.00/kg in 2010 (Khalidah, 2009).It seem that the increasing of mud crab price has encourage many coastal fishing communities to initiate trials in floating cage, in specially designed earthen ponds and more recently in pen enclosures in mangrove forests. Other factor that contributed to increase of mud crab farming is the physical characteristic of mud crab itself which is high tolerance to both nitrate and ammonia. High tolerance is beneficial for mud crab culture due to ammonia is often the most limiting factor on closed aquaculture systems. Their high ammonia tolerance may be attributed to various unique physiological responses which may have arisen due to their habitat preferences (mangrove forest). However, the larval survival is low and need to further investigate using alternative approaches. The first studies of crab seed has been done in Malaysia since 1995 by the Inland Fisheries Branch, Department of Agriculture, Sarawak (Tan, 1997) but the survival rates of megalopa are low. Since there is still no commercial-scale hatchery production of S.serrata, all forms of mud crab culture depend on natural seed supply. Currently, we still do not have any mud crab stock enhancement in Malaysia such as habitat improvement and restocking. However, there are studies has been made by Kosuge(2001) in brief assessment of stock of mud crab Scylla sp. in Matang forest, Malaysia and proposal for resources management. He proposed to the management plan of Matang Mangrove forest by provided separate fishing restrictions area and other indirect effect and basis information for management of mud crab resources. Broodstock management Berried S.serrata female were caught in open sea by using Trawl net. The broodstock were migrated to the shore for their spawning. The broodstock are commonly scrubbed to remove mud, encrusting algae, infestations and detritus before introducing the wild broodstock into the hatchery. Selection of good quality of broodstock has been discussed by several researchers in term of captive spawning pattern, environment manipulation, fecundity, egg size, egg quality, nutritional status, broodstock husbandry and stress and microbial influence. Mating process occur when the female is in soft shelled state just after moulting .While the female in soft shelled, the male of S.serrata were inseminated to the female for mating(Phelan et al,2007). Maturing and spawning in S.serrata species for tropical country shows high incidences of maturation in females appear to be associated with seasonal rain fall. During the spawning, the female mud crab were migrates to the sea to spawn and release their planktotrophic larvae (Vay, 2001). Normally, the duration of eggs to hatch may take 30 to 40 days. Factor that contribute to hatching success are environmental control such as salinity, temperature and photoperiod. Normally, the broodstock were kept in salinity at range of 30-35 g/L for captive maturation and spawning of S.serrata in the hatchery (Mann et al., 1999).Salinity is a one of the factor that can stimulate the hatching rate of mud crab S.serrata. A high hatching rate (93.6 %) of mud crab at salinity of 35 ppt was reported by Rusli et al. (1994) when incubated at water temperature of 29-30 oC. This report also indicated low hatching rate achieved when incubated at salinity 20 ppt to 30 ppt which is hatching rate dropped to 65. 9%-69.6 % .Moreover, Salinity at 15 ppt were lowered the hatching rate (15.2%) and the larvae died within 4 hours after hatching. In the mud crab, egg incubation period is stimulated by temperature in the range of 25 oC and 35 oC. A shorts period of egg incubation of broodstock is 10 days were recorded by Hamasaki (2003) .The temperature were varied seasonally as the broodstock were incubated. Different season has different range of temperature and as increasing temperature in the ranges 20.3-30 oC, the egg incubation period were decreased from 30 day to 10 day. In addition, lower temperature in the range of 18- 22 °C (Mann et al., 1999) has higher hatch rate and larger egg. It seems that temperature can affect the period of egg incubation and hatch rate of mud crab S.serrata. In term of fecundity, mud crab at large size has high fecundity (7.98  ± 1.79 million eggs) with crab size between 146 and 181 mm carapace width (Churchill, 2003).To get a good quality egg ,many factors have been study to determine the egg quality of mud crab. Effect of colour egg and diet were observed by Churchill (2003) to determine a good egg quality. However, the egg colour varies at pale yellow, orange and orange red are not an indicator of egg quality due to indifference of hatch rate. In addition, there is no difference on female size and fecundity was reported on egg quality. Moreover, there have been few studies of diet for mud crab broodstock in effects on larval health and reproductive performance. Millamena et al. (2001) highlighted the importance diet feeding for mud crab broodstock on egg development and larval production. Three difference diets were tested (natural food (mussel and fish), mixed diet (natural food and formulated diet) and formulated diet), each diet is capable to improve maturing and spawning of broodstock mud crab S.serrata. However, Broodstock performance and larval quality were improved when fed with mixed diet. In all treatment, all zoea larvae were successful reared to megalopa when fed mixed diet and the female were ablated. In addition, High fecundity and total zoea were obtained when the female are performed eyes stalked ablation method. Low survival rate of larvae may occur due pathogen and disease from the broodstock. Broodsrtock mud crabs are usually infested with ectoparasite, fouling organism, fungal and bacteria. Leaňo (2002) identified two species of Haliphthoros, namely H. philippinensis and H. milfordensis .Normally, Haliphthoros spp. were founded among broodstock which aborted their eggs prior to hatching. They reported that H. milfordensis was pathogenic to spawned eggs of S.serrata and it was observed the infection rate of H. milfordensis is 2-5 % at two day after inoculation of zoospores with increasing infection rate ( reaching up to 10% ) at five days. While, H. philippinensis is not pathogenic to spawned eggs of S.serrata. Other research on the ectoparasite is Lagenidium. The parasites may infest the recently hatched zoea of mud crab and ended in mass mortality (Prastowo and Wagimsan, 1996) .According to Zafran et al. (1993), Lagenidium grew best at 35oC and tolerated temperatures from 20-40oC and pH from 4 to 11. Fungus can be killed by exposure to 10 ppm formalin for 24 hours and it safe for zoea compare to 20 ppm formalin for 5 hours. To improved survival rate of larval, research on control Lagenidium in mud crab larval rearing has been conducted by Zafran and Taufik (n.d) and Prastowo and Wagiman (1996). Five kinds of fungicide (treflan, malachite green, formalin, potassium permanganate and caltocyn) have been studied in controlling the fungus and their toxicity to mud crab larvae. The minimum effective concentrations of treflan, malachite, formalin and permanganate to inhibit zoospore production were 0.1 ppm, 0.2 ppm 14 ppm and 9 ppm. High survival rate and hatching rate were reported by Prastowo and Wagiman (1996).Healthy zoea were recorded when zoea where treated with mixtures of caltrocyn (1.3 ppm) and treflan (0.02 ppm) in combination with water exchanged at the rate of 50% every three days. Effect of antibiotics (Penicillin G and Polymixin-B) in feeding treatments (rotifers and Artemia nauplii) has been tested by Kasry (1986).From his experiment, Kasry (1986) found that higher larval survival (52.1 %) at zoea 5 were obtained when the larval fed with combination of antibiotics (35 ppt Penicillin G and 7 ppm Polymixin-B), rotifer and artemia at density of 15 individual per ml. Previous studies on the luminescent vibriosis were originally reported in culture shrimp (Penaeus vannamei larvae).It is also a devastating disease in crab larvae. The experiment on the vibrios to zoea of mud crab were reported by Parenrengi et al (1993).They conclude that V. catch, V. alginolyticus and V. Parahaemolyticus are pathogenic to zoea but considered moderate compared to V.harveyii (Boer et al. ,1993; Parenrengi et al.,1993). It seems that zoea is very sensitive to luminous bacteria and it may contribute to the high mortality during early larval stage. Larval rearing Several studies were done in various aspects such as feed, stocking density, feeding protocol, disease and cannibalism to improve the survival of mud crab larvae. Moreover, others species of crab such as Chinese mitten crab (Eriocheir sinensis) in China (Zhang et al. ,1998; Li et al. ,2001), and blue crab (Callinectes sapidus) in Chesapeake Bay (Secor et al. ,2002; Zmora et al. ,2005) has been successful culture at the hatchery scale. Studies on the hatchery scale larval cultures of mud crab were conducted extensively by Australia country begin 1992. Seed stock of mud crab in Australia is dependent on hatchery while the wild seed stock is banned under their management plan in order to control mud crab fisheries. Low survival of mud crab larvae cultures for zoea to megalopa were recorded by Quitino (2001), Fortes (1999) and Nguyen Co Thach (1997) and had survival rate of 10%, 25 % and 1.5% respectively. Feeding and nutrition During the growth and moulting of mud crab larvae, the larvae are going through 5 zoea stages from zoea 1 to zoea 5 and metaphases to megalopa and crablet (Phelan et al., 2007). The hatched larvae leads a planktonic life and when they moult to megalopa stage, they migrated to the estuarine area and grow into adult in estuaries as a benthic juveniles (Vay,2001) .Moreover, early zoea stage shows the digestive system is not well develop and lack of enzyme to support the process of breakdown of food particle (Kumlu, 1999). The early zoea is 1 mm long (Phelan et al., 2007) and occupied with forked tail. The forked tail of larvae is used to capture food and transfer to their mouth (Zeng et al., 1991). During the megalopa stage, the pincher are developed and this development can causes the increasing of cannibalism by grasping among the larvae as survival rate is low (1.55-8%) recorded by Quinitio et al. (2004). Effects of feed and feeding on growth and survival of mud crab larvae have been tested by  several researchers. Yunus (1992) and Wang (2005) found that a higher density of rotifer at 60 ind/mL and 40 ind/ml are required to attain higher survival rates. A study on early feeding has been tested by several researchers such as live Artemia, cryst Artemia, copepod and rotifer. They found that, the early larval stage (Z1 and Z2) were physically weak to search food comparing to Z3, Z4, Z5 and megalopa due to physically active searching food. Currently, survival rate during Z1 and Z2 were improved when larvae fed rotifer. Further, decapsulated cyst of Artemia were tested by Jerome et al. (2005) to improve survival larval at early stage but the result were reported poorly. It seem that a high mortality at Z1 and Z2 due to unsuitable diet size where the size of SS type rotifer (147 ±11  µm) is bigger than size of the mouth opening of Z1 (100  µm) (Setyadi et al. ,n.d). Instead of live feed, there is a development of microbound diets for larval culture of mud crab S.serrata. Currently, the research on the nutritional requirements of S.serrata is limited. May-halen et al. (2006) tested three different microbound diets (fish meal, dried rotifer and dried artemia).The survival rate of megalopa to crablet stage showing lower survival those fed microbound containing dries rotifer and dried Artemia compare to microbound containing fish meal or squid (46.7% to 60.0%). The highest survival of megalopa to crablet was fed live Artemia (80%).Other studies on microboud diet were tested from zoea 3 to zoea 5, a high survival rate and development rate at the zoea 3 to zoea 5 stage (66%) were recorded for larvae fed the 50%:50% combination of microbound diet and Artemia from his experiment .They concluded that the microbound diet particle has a great potential for both zoea and megalopa diet and it is cost-effective for seedling production of mud crab S.serrata. Another factor that contributes to mortality in mud crab larva culture is due to poor nutritional, especially in highly unsaturated fatty acids (HUFA) in live food and cannibalism among megalopa and crablet (Truong, 2008). A study conducted by Suprayudi (2004) showed that the effects of Artemia enriched with eicosapentaenoic and docosahexaenoic acid on survival and occurrence of molting failure in megalop larvae .The larvae were fed enriched Artemia with different type of oil. Enriched Artemia appears to be superior to unenriched Artemia. High survival of larvae can be maintained and accelerating intermolt by provided an optimum EPA and DHA at 0.71-0.87% and 0.49-0.72% for larvae feeding. Further, the finding result on the level of EPA and DHA for survival larval were supported by Mann et al. (2001) as his found there were no significant improvement in larval survival as the mud crab larvae fed enriched Artemia at the levels of EPA (39 mg/g) and DHA (15 mg/g) .Moreover , Mann et al. (2001) found that the phospholipid is one of the nutritional component need to study in effect of survival of mud crab larval .Currently ,there are no study on phospholipid in the diet of mud crab larvae. Another report by Suprayudi et al. (2002) where indicated that survival rate of S.serrata increase with the increase of the total (n-3) highly unsaturated fatty acid (ÃŽ £ (n-3) HUFA) content of rotifers. From his experiment, Suprayudi et al. (2002) found that the total (n-3) highly unsaturated fatty acid (ÃŽ £ (n-3) HUFA) in rotifer can be increase from 3-5 mg/g to 7.6-8 mg/g. In term of survival for each larval stage, Suprayudi et al.(2002) found that high mortality through the moult to megalopa to first crab were recorded after fed boosted rotifer at 31 mg/g ÃŽ £(n-3) HUFA. Other research on the boosted rotifer indicated that a high mortality at metamorphosis to megalopa with fed boosted rotifer containing ÃŽ £(n-3) HUFA levels above 6 mg/g(Hamasaki et al. ,2002 ) .It seem that the specific (n-3) HUFAs may be more important for growth mud crab of mud crab larvae To improve survival rate of zoea and larvae nutrition, Suprayudi et al. (2004) examined the effect of essential fatty acids (EFA) on the survival, development and bioconversion of fatty acids in mud crab S.serrata larvae. From his experiment, he found that the content of EFA in Artemia were strongly influenced the survival of mud crab larvae compared to rotifers. They found that EFA deficiency were reported at each larvae fed unenriched Artemia, enriched Artemia and enriched rotifer, indicating that DHA was superior to that of EPA. They conclude that mud crab larvae have a limited or negligible capability to convert C18 unsaturated fatty acids to highly unsaturated fatty acids. Disease of mud crab larvae Bacteria infestations are major problem for rearing larvae and contribute high mortality. Studies on the bacteria profile in rearing water with Scylla serrata larvae was noted high mortality from zoea 5 to megalopa due to the increase in luminescent bacterial load in the larvae (Quitino, 2001). Further, protozoa can contribute high mortality during egg and larval stages. This protozoon has an ability to interfere with gas exchange that blocked respiratory surfaces of the egg and larvae (Lavilla-Pitogo et al., 2004). Although these organisms do not invade the underlying tissues, they make it difficult for the affected larvae to move and to feed. Cannibalism Cannibalism behaviour of mud crab larvae indicated high mortality when metamorphosis from megalopa and crablet stage. Study by Juliana (1999) showed that high survival at crablet stage when reared with mud substrate and without shelter. Crablet were tested with different treatment such as coconut leave, mangrove twigs and mud substrate. In addition, asynchronous moulting of mud crab larvae is a one of the factor that contributed to the increased mortality during zoea 4 and zoea 5 (Quinitio, 2001). Water quality parameter The optimal condition in rearing mud crab larvae has been conducted in China, Vietnam, South Africa and Australia. Parameters that have been studies are temperature, salinity and total ammonia. The early larvae has a ability to tolerate with range temperature between 25 oC to 30 oC but shorten their development time when reared at a upper temperature ( 29-30 oC) (Dat ,1999; Li et al. ,1999; Quinitio et al. ,1999; Mann et al. ,2001; Quinitio et al. ,2001). In addition, the highest survival rate and growth rate were recorded when the larval reared at higher temperature ranged 28.5 oC to 31 oC and the minimum were recorded when the larval reared at low temperature ranged 22-24 oC (Marichamy, n.d). The optimal salinity for all larval stages larvae are 27 ppt to 31 ppt (Gui-Zhong, 2005).Other experiment on the optimal salinity for larval rearing was observed by Marichamy (n.d).From his experiment, he found that the optimal salinity for larvae rearing was 35 ppt with the highest production of larval and poor survival when reared at the lower salinity (32-33 ppt).However, high salinity at 36 ppt were not suitable for larval growth. To improve survival of zoea, Baylon (2001) were investigated the effect of salinity on survival and metamorphosis from zoea to Megalopa of the mud crab S.serrata. Each of larval stages (Z1, Z2, Z3, Z4, and Z5) of Scylla Serrata was tested with different salinity (12, 16, 20, 24, 28 and 32 ppt) and different salinity regime. In all treatment, highest metamorphosis to megalopa occurred where salinity was constant at 32 ppt. Further, there is no significant difference on the duration of development of the surviving larvae in all salinity regimes. Other factor that contributes to high mortality is ammonia. However, there is a few research has been conducted on the ammonia tolerance in mud crab larvae. Churchill (2003) tested concentrations of total ammonia ranged (NH3 and NH4 +) ranged from 25 ppm to 450 ppm at 25 ppm intervals. They concluded that S.serrata larvae are highly tolerated with high levels of nitrogenous waste. From the stress test ammonia, the optimum concentrations of total ammonia for zoea mud crab are 20 and 30 mg/l where the zoea activity was remained normal during total ammonia test. Currently, there is no research has been conducted on the tolerance of Scylla larvae to extremes in pH and oxygen concentration. Culture systems Attempt to develop techniques for mud crab (S.serrata larvae) culture system has been made since 1999. Most of the culture systems were adapted from culture shrimp (Penaeus vannamei larvae) system. Currently, there are three different culture system have been used in larvae rearing ranged from exchanged of water system, mesocosm system and green water culture system. To control water quality during the larvae rearing, exchanged of water were done by either a constant flow-through basis, or by draining or siphoning 50-85% of the tank volume daily and replacing it with clean seawater, or by recirculation a biofilter (100% every 2-3 hours) (Nghia et al. 2001).Under green water culture system ,the water were not exchanged for the first three day .Thereafter, water exchange is slowly increased from 10-20% per day for Z2-Z3 to between 40 and 50% per day at the end of the rearing cycle (Z4-M) (Mann et al. ,1999 ;Quinitio et al. ,2001). For the mass culture,mesocosm system has been used in Japan where the tank are partially filled with green-water at Z1 (20-25% volume. As the larvae metamorphosis to Z2 and Z3 stages, clean seawater were used instead of green water and the water exchanged on flow-through basis (Hamasaki et al., 2002) during the Z4 and M stages. To improve water quality on the bottom of tank, dead larvae and uneaten food that accumulate on the tank bottom are daily siphoned out of rearing vessels (Quinitio et al., 2001; Baylon and Failaman, 2001) and care must be taken to avoid siphoning out larvae which have sunk to the bottom of the container. Another problem during larvae rearing is a development of biofilm on tank sides .A high survival were achieved when the biofilm was removed daily (Williams et al., 1998).In addition, improper cleaning the biofilm can release large amounts of bacterial flock into the water column. Green water culture system is functioned by provide the larvae with microalgae such as Tetraselmis, Skeletonema, Chlorella, Nannochloropsis, Chaetoceros and Isochrysis at densities ranging from 5104 to 5105 cells/ml (Djunaidah, et al. ,1998; Dat ,1999; Mann et al. ,1999; Williams et al. ,1999; Zeng and Li ,1999; Mann et al. ,2001; Quinitio et al. ,2001) in order to increases survival and to serve as food for rotifers and Artemia. However, there is not scientific study on the effect of background algae on larval survival and growth of mud crab S.serrata. Basically, the mud crabs inhabit a turbid estuaries and it seems to require phase. However, there is no significant effect on survival between 12 and 18 hour photoperiods (Nghia et al. ,2001).Further, there is a experiment on the effect of tank colour (black, dark green, maroon, sky blue and white) on larval survival and development of mud crab Scylla serrata .From his experiment, Abed Golam et al.(2005) found that a higher survival and shorter development of zoea were recorded in darker colour background compare to white background .Moreover, the larvae where reared with black background have more efficient feeding as reduced settlement on the bottom of rearing tank. They concluded that background colour was significantly affecting larval survival.

Respecting Teachers Essay

Gender differences are beginning to appear in the content men and women are downloading to their mobile phones. Games are mainly downloaded by men, while women are leading the current craze for ringtones. The findings form part of a quarterly survey of mobile usage commissioned by mobile marketing firm Enpocket. The research also found that 3G video is slowly growing, though services are only being used by a small proportion of UK mobile phone owners. Less than 3% use 3G, up from just 1% a year ago. The research also found that 3G video is slowly growing, though services are only being used by a small proportion of UK mobile phone owners. Less than 3% use 3G, up from just 1% a year ago. Young audience Mobile gaming is proving more popular, with 1.9 million people (5.8%) downloading a game to their phone in the last three months. It is predominantly men – 58% – that are keen to play games on their phones, with the majority being under 34. Young women on the other hand are getting into ringtones. They make just more than half of the 5.9 million people who downloaded a ringtone to their phone in the previous three months. Most pop hits are available as ringtones, costing between  £1.50 and  £3.50 per download. It is estimated that  £70 million worth of ringtones were sold in 2003. They are becoming so popular that accountancy firm KPMG is to release a fortnightly chart on the 20 most popular ringtones. The fact that people are prepared to spend money and time downloading content to their mobiles is great news for mobile firms. â€Å"Mobile owners are getting to grips with the more advanced features on handsets, beyond SMS,† said the chief executive of Enpocket Jonathon Linner. There are some things for companies offering 3G services to ponder though. As well as the low number of people using existing services, the survey found that less than 40% of those that own a 3G handset were actually using 3G services.

Cyber war Vs Cyber terrorism Essay

In this time and era, we have witnessed the emergence of electronic resources as the most important development of the modern day communication system. Technologies such as cellular phones, home computers, the internet and websites have added another dimension to the way we live our lives today. This presentation seeks to address and analyse the negative and positive aspects in view of the introduction of computers and telecommunications techniques as follows: Firstly, it raises awareness with regard to the new age of crimes, termed as cyber crimes. The paper focuses, in particular, on the difference between the two common types of cyber crimes, cyber war and cyber terrorism. Secondly, the paper examines the limitations and impact of having graduates through e-learning. Thirdly and lastly, the paper discusses on whether computer practitioners should be required to have a practicing license as it is with other professionals such as doctors, lawyers and teachers. 1. (a) Difference Between Cyber War and Cyber Terrorism The end result of both cyber war and cyber terrorism is the same, to damage critical infrastructures and computer systems. The major difference being  that cyber war is launched by governments whereas cyber terrorism is launched by individuals or a group of individuals. Cyber war, often done in conjunction with traditional military attacks, is an organised attack by one nation against another nation’s information and communication systems with an aim of gaining an advantage over the enemy by disrupting their ability to fight back. Cyber war attacks often targets an enemies systems such as command and control systems, intelligence collection and distribution, information processing and distribution, tactical communication, troop and weapons positioning and so on. For instance, when the United States of America invaded Iraq, they disrupted the country’s communication and defence systems, crippling their ability to find and take down US aircrafts. On the other hand, cybe r terrorism is when individuals or terrorist groups use computers, computer networks and the internet against persons or property to intimidate or coerce government, civilians, society in order to reach political, religious or ideological agenda. The things that are targeted are power plant systems, telephone systems, transportation systems, water or oil pipelines, financial institutions and so on. ([online] Available at: community.mis.temple.edu/mis2901001†¦[Accessed 5 April 2014]) Cyber terrorism takes many forms. One of the more popular is to threaten a large bank. The terrorist hacks into the bank’s system and then leave an encrypted message for senior directors demanding for a sum of money. If the bank does not cooperate, the terrorist threatens to use anything from logic bombs to electromagnetic pulses and high-emission guns to destroy the bank’s files. Most banks would rather pay the money than have the public know how vulnerable they are for fear of loss of business. ([online] Available at: csciwww.etsu.edu/../cases.htm [Accessed 6 April 2014]) One practical example is where banks in Zambia have lost an estimated US$4 million to cybercrime through Automated Teller Machines (ATMs) withdrawals. This was reported in the local Post newspaper dated 14 June 2013. This was after the state police discovered a scam in which three foreign criminals had recruited and trained Zambians in cyber-crime. ([online] Available at: www.postzambia.com/post-read †¦article [Accessed 6 April 2014]) Cyber terrorism can also include terrorists getting secret data from defence files, network with other terrorists, or raise and manage funds for terrorism by hacking. (b) Limitations and Impact of Having Graduates   Through E-learning E-learning has become an increasingly popular learning approach in higher educational institutions due to the rapid growth of internet technologies. Many foreign renowned universities offer all types of programmes ranging from Bachelor, Master and PhD programmes, to Short Courses. Essentially, emerging evidence suggests that having graduates through e-learning has substantial beneficial impact on social and economic development of our societies today and includes the following. It has enhanced skills development to would be graduates and their countries to cope with the demands of the 21st century where rapid change and globalisation is taking place. For instance, graduates have acquired an improved ability to conduct independent research, think critically to solve problems through the use of e-technology to communicate and collaborate. It has lead to an increased student turnover because of its flexibility and cost effectiveness and hence has broadened educati onal opportunity for many, especially financially disadvantaged students and those with disabilities. This has resulted in an increased human resource base and enhanced economic progress from direct job creation in the technology industry as well as from developing a better educated work force, much needed in developing countries such as Zambia. Online access promises a new access route for millions of students. This new approach of learning facilitates different students at different continents to attend the same classes almost at the same time. It has brought about improved learning methods and teachers have a more positive attitude towards their work and are able to provide personalized learning. On the other hand, although e-learning has brought about many benefits for students and organizations alike, it also has its limitations. In order to perform the tasks required by system, an e-learning environment requires basic state of the art equipment and minimum level of computer skills. Thus, a student that does not have the minimum computer knowledge, or have access to these equipment is disadvantaged and will not succeed in an e-learning program. Certain subjects, such as sports and public speaking, require physical exertion and practice. Thus, they cannot be applied in an e-learning environment. Needless to say, it can be a useful companion to traditional education for teaching backgroun d and technical information. A successful e-learning program requires students that are well organised, self motivated and have  good time management skills. In other words, an e-learning program is directly related to the amount of effort applied. Successful e-learning students are able to study independently and incorporate study time into their busy lives. Students that lack discipline and are not good at time management are disadvantaged and will not succeed. E-learning requires good reading and writing skills. Most activities and communications are written, and thus, the ability to efficiently interpret instructions is a critical skill to a successful e-learning program. Students that are not comfortable with the ability to express themselves through writing will not succeed in e-learning. 2. Are computer practitioners similar enough to other professionals that they should be required to have a License too? Licensing is not currently required for computer practitioners but is being considered by several professional computing organizations and is believed, in principle, as necessary as the certification and licensing of doctors, lawyers, teachers, hairdressers and other professionals. The question of licensing professional s in general is a very controversial and political question. Licensing generally means that to practice a certain profession requires a government licensee, usually administered through a professional organization. The general theory of licensing professional is that it is supposed to help the general public outside the professional to be assured that someone else is capable of doing certain jobs. For instance,  one of the top e-learning institutions, the University of Liverpool in conjunction with Laureate Online Education offer 41 distance learning courses from a wide area of disciplines. The notion that degrees through e-learning are perceived not to be as rewarding or valuable as full-time traditional degree has been proved not to be the case. In fact, in the late 1990s, the Quality Assurance Agency for Higher Education of the British Government measured academic excellence in more than 100 universities, including the Open University. Surprisingly, the Open University was ranked in the top ten of British Universities in terms of academic excellence. The only underlying difference between a traditional degree and e-learning degree is the manner in which information is conveyed. The traditional setup has been based on a face to face communication where students and lecturers are brought together at the same time and the same place in classes,  laboratories and recreation centers for the purpose of learning, whereas in e-learning systems use technology to separate the learner from the teacher, and the learner from the learning group while maintaining the integrity of the learning process. Follow up statistics placing the Open University in the top 10 with Oxford and Cambridge have been repeated for several years and cannot be statistically be explained as a mere coincidence. ([online] Available at: http.//www.webbasedtraining.com/ [Accessed 3 March 2014]) The main focus of this presentation is to gain insights into critical issues confronting two major stakeholders in the new era of WBT, the student and faculty. The question at hand requires objective views on the advantages and disadvantages of WBT from a student’s point of view as well as advantages of WBT from the college’s point of view. It further requires identifying ways that studying from a website is better than studying from written text as well as discuss in details the social and economical benefits and limitations of E-technology in Zambia. Systems Development Life Cycle The second part of this presentation discusses a linier Systems Development Life Cycle (SDLC) which is a technique used to assist developers effectively develop information systems. ‘Gaining competitive advantage and improving information delivery will urge an organization to restructure its activities. The information system has to be developed to suite the business scenario and objectives. It needs to be carefully planned and activities well thought of.’ (Ndhlovu, 2009). Thus, in an effort to answer the question at hand a description of the stages involved in a SDLC using annotated diagram shall be discussed. In addition, the discussion shall also include a description of techniques which can be used to investigate the existing system of an organization identifying the advantages and disadvantages of each and also give an alternative to SDLC for developing systems. Having said that, details of the mentioned topics in question is as follows. a) Web-Based Training Advantages and Disadvantages of WBT: Student’s Point of View Advantages Utilisation of the World Wide Web is a current and extensive source of  information and relatively easy to use. Some of the advantages from a student’s point of view include the following. There is unlimited source of information on the internet as compared to textbooks and class lectures as it provides a variety and quality of learning materials. Encountering a new experience of sourcing information on the web increases a motivation to learn among students. For example, the web allows browsing from one link to another on a particular subject or topic Access to meaningful resources foster critical thinking skills and allows the student to see new ways of interpreting and evaluating information. For instance, gathering view points and knowledge from various internet sites cause students to debate previously held values and ideas which they may have had misconceptions. Gain of competence with technology by learning to navigate and use the web successfully, apply computer skill s, use of conferencing tools such as e-mail and listservs. Integration of technology with content-related work provided a more meaningful interaction with the subject matter. For example, students reflected on the lack of relevance in acquiring computer skills in isolation noting that when combined with content, those applications become a tool to improve learning in their field of study. Technological aspects of course assignments encourage cooperative dialogue rather than isolation. For example, e-mail and listservs are used regularly providing a valuable resource for support and collaboration among classmates for help in completing assignments, support with technological frustration and to share acquired skills or content resources. In addition, e-mail communication with instructors gives a student individual attention that is not apparent in a traditional coursework setup. E-mail utilization has many assets that face-to-face classroom contact lacks. For example, student need not wait for class time in order to get or clarify a piece of information. The student who would normally shy away and not ask a question in class or participate in a class discus sion are more comfortable using e-mail as a medium of communication and thus is not left out on the much needed information. For the student, online course allows them to integrate work, family and school more efficiently as it eliminates travel time to and from class for commuters. Disadvantages The positive aspects of WBT are countered with some frustrations that are  experienced by some students. These include the following. Student lack of computer skills, internet server being down, difficulty in accessing computer, use of obsolete computers and lack of technical and instructional support are some of the frustrations that a student may encounter. Required assignments are time consuming as mastering computer application tools and learning to navigate the web efficiently take up most of the time. Advantages of WBT: College’s Point of View Higher education is evolving, consumer needs are shifting, and competition for students is increasing. Consequently, institutions must be driven to some extent by the needs and demands of the consumer. To satisfy the unique needs of growing numbers of nontraditional students and to make graduate degrees more attractive and feasible, the availability of online courses and distance learning opportunities is essential. Most of the faculties consider technology applications in university courses as the wave of the future citing their main reason for wanting its continuity as mainly being the benefits they believe their students receive. Moreover, in this time and era, a faculty member who does not use technology is often considered out of date and out of touch with skills that are needed for the coming millennium. Faculty respondents consistently identified convenience and improved learning as advantages for students enrolled in Web-based instruction. Other advantages identified by facul ty are as follows. Students gain knowledge on how to use numerous technology-based applications such as e-mail, PowerPoint, listservs, graphics programs, and HTML, many of which are considered essential skills for today’s workforce. Students also gain comfort with the medium, anxiety levels are reduced, and they are more willing to explore the potential of technology applications. Students tend to become independent learners, are more motivated to explore related topics on their own, and develop critical thinking skills. The quality of completed assignments is often better than in the traditional classroom because students have more time for reflection and better access to resources. More information can be included in a course with the potential for students to expand on the information received by providing links to related sites. Many students will click on a link more readily than obtaining a print resource identified in a bibliography. Students learning how to access the extensive  resources available on the WWW, online databases, and other technology-based resources. Student convenience. For example, online classes provide students with 24-hour access, eliminate the need to travel or find parking, and eliminate scheduling conflicts with jobs or family. These advantages may particularly benefit graduate students and nontraditional students. Connecting s tudents with technology allows the student to become part of a global community. Information and ideas can be exchanged with other students and experts throughout the world using e-mail and listserv discussions. Collaboration and communication among students are fostered, as well as communication between instructor and student. Online Studying Vs. Written Text Studying Among the several ways that studying from a website is better than studying from written text three distinct ways include the following. Text books become outdated almost immediately after publication and cannot be updated until the next publication which may take several years down the line. Information on the website can be updated daily and printing errors are corrected immediately. Written text is limited to the information on the page whereas educational websites can link to an infinite number of other educational sites to give supplemental detail in as much as possible on a particular subject or topic. Textbooks are limited to the points of view of their authors whereas the website allows multiple view points, which is essential for critical thinking especially if the author is too vague about a particular topic. ([online] Available at: English.varsavskyfoundation.org/education [Accessed 7 March 2014]) b) Social and Economical Benefits and Limitations of E-technology in Zambia Zambia is one of a number of countries in the Southern African region that have sought to include e-technology in its national development plans. E-technology is believed to contribute to improving development outcomes in two main ways: E-technology-based knowledge and products contribute directly to wealth creation. The use of e-technology contributes indirectly to national development through its impact in social and economic sectors such as agriculture, health and education, and by empowering individuals to take advantage of new opportunities. For example,  AfriConnect, in partnership with the Zambian Ministry of Education, have been piloting a project aimed at bringing web-based e-learning to schools in different parts of the country. The objective is to move from the traditional chalk-and-talk pedagogy to enquiry-based learning, while at the same time bringing the option of lifelong learning to people who have already left school. Individuals also benefit from the availability and use of e-technology in a number of ways. For example, by substituting phone calls for travel, which saves time and money, and by using e-technology to obtain information on prices, for their own produce and for purchases. In these various ways, e-technology can have a significant impact on a country’s ability to achieve the Millennium Development Goals (MDGs). There are, however, also constraints on the potential impact of e-technology in many developing countries. These constraints include inadequate technical infrastructure, limited human skills to use available networks and services, the relatively high cost of communications equipment, and poor policy and regulatory environments. These factors reduce the scope for countries and communities to realise the potential of e-technology for development. Question 2 Solution (a) Model of the Systems Development Life Cycle highlighting the maintenance PhaseThe systems development life cycle (SDLC) is a conceptual model used in project management that describes the stages involved in an information system development project, from an initial feasibility study through maintenance of the completed application. In general, an SDLC methodology follows the following steps: 1. Planning Stage The existing system is evaluated. Deficiencies are identified. This can be done by interviewing users of the system and consulting with support personnel. 2. Analysis Stage The new system requirements are defined. In particular, the deficiencies in the existing system must be addressed with specific proposals for improvement. 3. Design Stage The proposed system is designed. Plans are laid out concerning the physical  construction, hardware, operating systems, programming, communications, and security issues. The new system is developed. The new components and programs must be obtained and installed. Users of the system must be trained in its use, and all aspects of performance must be tested. If necessary, adjustments must be made at this stage. 4. Implementation Stage The system is put into use. This can be done in various ways. The new system can be phased in, according to application or location, and the old system gradually replaced. In some cases, it may be more cost-effective to shut down the old system and implement the new system all at once. 5. Maintenance Stage Once the new system is up and running for a while, it should be exhaustively evaluated. Maintenance must be kept up rigorously at all times. Users of the system should be kept up-to-date concerning the latest modifications and procedures. (b) The systems development life cycle (SDLC), also referred to as the application development life-cycle, is a term used in systems engineering, information systems and software engineering to describe a process for planning, creating, testing, and deploying an information system.[1] The systems development life-cycle concept applies to a range of hardware and software configurations, as a system can be composed of hardware only, software only, or a combination of both.[2] The waterfall model is a sequential design process, often used in software development processes, in which progress is seen as flowing steadily downwards (like a waterfall) through the phases of Conception, Initiation, Analysis, Design, Construction, Testing, Production/Implementation, and Maintenance. What is systems development life cycle (SDLC)? (SDLC is also an abbreviation for Synchronous Data Link Control.) The systems development life cycle (SDLC) is a conceptual model used in project  management that describes the stages involved in an information system development project, from an initial feasibility study through maintenance of the completed application. Various SDLC methodologies have been developed to guide the processes involved, including the waterfall model (which was the original SDLC method); rapid application development (RAD); joint application development (JAD); the fountain model; the spiral model; build and fix; and synchronize-and-stabilize. Frequently, several models are combined into some sort of hybrid methodology. Documentation is crucial regardless of the type of model chosen or devised for any application, and is usually done in parallel with the development process. Some methods work better for specific types of projects, but in the final analysis, the most important factor for the success of a project may be how closely the particular plan was followed. In general, an SDLC methodology follows the following steps: 6. The existing system is evaluated. Deficiencies are identified. This can be done by interviewing users of the system and consulting with support personnel. 7. The new system requirements are defined. In particular, the deficiencies in the existing system must be addressed with specific proposals for improvement. 8. The proposed system is designed. Plans are laid out concerning the physical construction, hardware, operating systems, programming, communications, and security issues. 9. The new system is developed. The new components and programs must be obtained and installed. Users of the system must be trained in its use, and all aspects of performance must be tested. If necessary, adjustments must be made at this stage. 10. The system is put into use. This can be done in various ways. The new system can phased in, according to application or location, and the old system gradually replaced. In some cases, it may be more c ost-effective to shut down the old system and implement the new system all at once. 11. Once the new system is up and running for a while, it should be exhaustively evaluated. Maintenance must be kept up rigorously at all times. Users of the system should be kept up-to-date concerning the latest modifications and procedures.

Overview of Sociologys Conflict Theory

Conflict theory states that tensions and conflicts arise when resources, status, and power are unevenly distributed between groups in society  and that these conflicts become the engine for social change. In this context, power can be understood as control of material resources and accumulated wealth, control of politics and the institutions that make up society, and ones social status relative to others (determined not just by class but by race, gender, sexuality, culture, and religion, among other things). Karl Marx A house may be large or small; as long as the neighboring houses are likewise small, it satisfies all social requirement for a residence. But let there arise next to the little house a palace, and the little house shrinks to a hut. Wage Labour and Capital (1847) Marxs Conflict Theory Conflict theory originated in the work of Karl Marx, who focused on the causes and consequences of class conflict between the bourgeoisie (the owners of the means of production and the capitalists) and the proletariat (the working class and the poor). Focusing on the economic, social, and political implications of the rise of capitalism in Europe, Marx theorized that this system, premised on the existence of a powerful minority class (the bourgeoisie) and an oppressed majority class (the proletariat), created class conflict because the interests of the two were at odds, and resources were unjustly distributed among them. Within this system an unequal social order was maintained through ideological coercion which created consensus--and acceptance of the values, expectations, and conditions as determined by the bourgeoisie.  Marx theorized that the work of producing consensus was done in the superstructure of society, which is composed of social  institutions, political structures, and culture, and what it produced consensus for was the base, the economic relations of production.   Marx reasoned that as the socio-economic conditions worsened for the proletariat, they would develop a class consciousness that revealed their exploitation at the hands of the wealthy capitalist class of bourgeoisie, and then they would revolt, demanding changes to smooth the conflict. According to Marx, if the changes made to appease conflict maintained a capitalist system, then the cycle of conflict would repeat. However, if the changes made created a new system, like socialism, then peace and stability would be achieved. Evolution of Conflict Theory Many social theorists have built on Marxs conflict theory to bolster it, grow it, and refine it over the years. Explaining why Marxs theory of revolution did not manifest in his lifetime,  Italian scholar and activist  Antonio Gramsci  argued that the power of ideology was stronger than Marx had realized  and that more work needed to be done to overcome cultural hegemony, or  rule through common sense. Max Horkheimer and Theodor Adorno, critical theorists who were part of The Frankfurt School, focused their work on how the rise of mass culture--mass produced art, music, and media--contributed to the maintenance of cultural hegemony. More recently, C. Wright Mills drew on conflict theory to describe the rise of a tiny power elite composed of military, economic, and political figures who have ruled America from the mid-twentieth century. Many others have drawn on conflict theory to develop other types of theory within the social sciences, including feminist theory, critical race theory, postmodern and postcolonial theory, queer theory, post-structural theory, and theories of globalization and world systems. So, while initially conflict theory described class conflicts specifically, it has lent itself over the years to studies of how other kinds of conflicts, like those premised on race, gender, sexuality, religion, culture, and nationality, among others, are a part of contemporary social structures, and how they affect our lives. Applying Conflict Theory Conflict theory and its variants are used by many sociologists today to study a wide range of social problems. Examples include: How todays global capitalism creates a global system of power and inequality.How words play a role in reproducing and justifying conflict.The causes and consequences of the gender pay gap between men and women. Updated  by Nicki Lisa Cole, Ph.D.