Cell Phone Technology Essay Example for Free

Cell Phone Technology Essay Technology had become engrained in our society. Everywhere people are using cell phones, including children and teenagers. Cell phone technology and technology in general have change the way we do everything in our society. Technology has dramatically altered our world. They have become a necessary part of everyday life so much so that it is leaking into the education world as a new tool despite the concern of the negative effects of cell phone technology. There is a new wave in some schools around the United States. There are some districts that are embracing the use of cell phones in the classroom. Some administers have come around to the thinking that the use of this technology in the classroom can be of benefit in the learning setting. There are also concerns that the same technology can be too distracting for students. However, the use of cell phones in the educational world is worth looking at despite some of the concerns that many adults share. Texting has become the preferred method of basic communication between teenagers and their friends. Seventy-five percent of 12-17 year olds own cell phones, which is up from forty-five percent in 2004 (Lenhart, 2010). Phones have no doubt become an indispensable tool in communication for teens. Eighty-eight percent of teen cell phone users are text messengers (Lenhart, 2010). More than half (fifty-four percent) are daily texters. Among all teens, the use of texting has overtaken the frequency of every other form of communication. The concern about the overuse of cell phones is that it may have negative consequences in teenager’s education.  ¼ of text messages that teens send are sent during class. A survey conducted by Beneson’s online poll, polled 1,013 teens- eighty-four percent that have cell phones-show that a significant number of stud ents have information stored on their phones or has texted answers to their friends. The same poll also found teens send 440 text messages a week on average, 110 of them sent during class (Toppo, 2009). For this reason cell phone use is prohibited for use during the school say within most public schools in the United States. Most administrations and teachers feel that cell phone usage is a negative distraction and deterrent to learning. Administrators are often concerned about the inappropriate use of cell phones, which is the reason that there are restrictions of cell phone (according to Obringer Coffey, 2007, St. Gerard, 2006). Cell phones ringing can present unwanted distraction and for some students, sending and receiving text messages that can lead to cheating (according to Gilroy, 2003). There is also the real possibility of students posting improper pictures is a concern (according to Obringer Coffey, 2007). However, many are choosing to look at cell phones as a new learning tool in the classroom setting. Over the years we have seen on the news about students posting improper photos and language on social networking sites, which causes administrators and teachers to have a real concern. These concerns that many have are valid, and should be addressed. There have been many cases in which the abuse of cell phones has been a huge problem, but administrators want to take a chance on using cell phones in this setting. The important thing to keep in mind that there is down side, yes, but there is a way to monitor the use of this technology too. PPCD teacher Debra Vela, who has 17 years of teaching experience says, â€Å"Sexting, posting of improper photos and cheating may be a legitimate worry, but the benefits outweigh these negative points.† Students today are referred to as â€Å"Digital Natives† (according to Prensky, 2001). They have grown up with technology and multitasking, and in the habit of quickly processing information (Humble-Thaden, 2011). However, as cell phone technology expands with the possibilities of texting, web browsing and gaming have increased over the recent years and administrators are still worried about the distractions of electronic devices. A survey of students and parents by the group Common Sense Media found that almost seventy percent of schools around the country ban cell phone use during the school day (Schachter, 2009). There are some districts and administrators, though that are beginning to realize the potential of cell phones. It is a part an â€Å"anytime, anywhere† learning movement (Schachter, 2009). This leaves laptops and even smaller netbooks behind, in favor for more mobile, affordable and reliable handheld devices like â€Å"smartphones† that can run such programs as Windows Mobile. â€Å"Technology has finally progressed to where mobile devices are cheap and powerful enough to use,† observes Elliot Soloway, a professor at the University of Michigan (Schachter, 2009). A study of twenty-five mobile learning initiatives worldwide by the Joan Ganz Cooney Foundation Center at Sesame Workshop anointed them the wave of the future. â€Å"Just as Sesame Street help transformed television into a revolutionary tool for learning among young children four decades ago, advances in mobile technologies are showing untapped educational potential for today’s generation,† the report author’s wrote (Schachter, 2009). In 1969, the way children learned changed when Sesame Street aired on PBS. The loved Muppets of the educational show captured the hearts and attention of toddlers. The show taught them the basics of 123’s and ABC’s to the importance of friendships. Before the age of four, children had already learned the basics for their future education by watching this television show. The same is happening today with the use of cell phones. It is drastically changing the face of the way children learn and take information in. Fifth graders at Trinity Meadows (Keller, TX) spent most of their days on their HTC 6800 smartphones, using the GoKnow’s platform. Fifty-five students led the way in a pilot program using the new generation of cell phones and their advanced technology for educational ends. For example, students can draw the solar system on their devices and animate them to show them in real obit. Students can also upload assignments the teacher sends to the server and then the teacher can grade them and submit them back to the student electronically (Schachter, 200). At an early age, children are learning the advantages of technolog y, and will carry it into the future. They are learning to use cell phones as a learning tool, and making the best of what this technology has to offer. Children today have a chance to express themselves creatively and learn in a way that they are familiar with. They are at an advantage since they are already so use to using the technology the world has to offer. â€Å"Allowing children to use cell phone technology in the classroom will provide them with the tools for more creativity to create wonderful projects,† Vela says. This pilot program has shown that the use of cell phone technology in the classroom can be of benefit to the students. Not only that the teachers have a new method of reaching students that they otherwise would not have. With the use of cell phone teachers have new ways of teaching lessons, and the interactivity of these lessons are more likely to reach the minds of students. With the use of cell phone technology in the classroom the children that need a more creative outlet this provides them with platform to do so. Children that need this outlet can create and not be tied down to pencil, paper, marker, c rayons and glue. This allows them to be able to express themselves using the medium that they know best. Using cell phones in the classroom settings as a tool enables them to stay focused and interested in the things that they are learning. Technology is such an important part of everyday life, especially in cell phone technologies. And because of the increasing improvement of cell phone technology has allowed the next generation to use them in a whole new way to learn. Although, there is concern about the overuse of cell phones, the benefits may outweigh the negatives. â€Å"I still think students need to learn the ‘old fashion’ way because what happens if technology becomes unavailable to them? Also students need to be able to use their brains for higher learning,† says Vela. Technology is a wonderful tool to use in the classroom for all age groups. They can benefit from the interactivity of the Internet and all the information that the World Wide Web has to offer students as well as teachers. Children in today’s classrooms have an opportunity that past generations did not have. They have the chance to make a big impression on their lives by allowing themselves to use cell phones to their advantage not their disadvantage. The technology of cell phones has taken over almost every aspect of human activity. Adults as well as children have been consumed by the use of them, and now it has leaked over into the world of education. There are many concerns about the overuse of this technology, but many districts are taking the chance to embrace it and try it out in the classrooms. It has been shown that there are benefits for school children. Although, there is some debate about this issue it is important to remember that there is a need for balance. Reference Lenhart, Amanda. (2010). Teens, cell phone and texting. Pew Research Center Publications. Retrieved 3 June 2012 from http://pewresearch.org. Humble-Thaden, Beth. (2011). Student Reflective Perception of High School Educational Cell Phone Technology Usage. Journal of Technology Studies. Retrieved 3 June 2010 from http://web.ebscohost.com. Toppo, Greg. (2009). Survey: Many teens use phones in class to text or cheat. USA Today. Retrieved 3 June 2012 from http://www.usatoday.com. Schachter, Ron. (2009). Mobile Devices in the classroom. District Administration Magazine. Retrieved 4 June 2012 from http://ww.eric.com. Interview: Debra Vela, PPCD Teacher, 17+ years teaching.

Comparison Of Persistence Framework Computer Science Essay

Comparison Of Persistence Framework Computer Science Essay Compare and contrast the following persistence frameworks: Java Persistence API (JPA), Hibernate and Java Database Connectivity. What improvements were made in EJB3.1 and JPA2? Include topics of scalability, security, connection pools, connection factories, entity management, transactional context, query languages, ORM, JCA, JNDI, the DAO-VO design pattern and specifically persistence layer(s) on a distributed n-tier enterprise platform in your discussion. Java Persistence API (JPA) JPA is an abstraction above JDBC that makes it possible to be independent of SQL. The main components of JPA are: ORM: Object relational mapping is a means to map objects to data stored in relational database [1]. JPA uses annotations and/or XML descriptor files to map POJO based java objects to relational database tables. CRUD: An entity manager manages lifecycle of JPA entities. It performs database related operations like create, retrieve, update and delete. JPQL: Java persistence query language allows writing CRUD queries using an object oriented query language. JTA: Java Transaction API provides transactions and locking mechanisms while accessing data concurrently. Callbacks and listeners: They hook business logic into the life cycle of a persistent object. Hibernate Hibernate is an Object relationship mapping framework. Hibernate helps in mapping POJO Java classes to SQL database tables. It has the power of significantly reducing development time. Hibernate uses annotations and/or XML (mapping) descriptor files to map the POJO Java objects in the application domain to relational database tables. Hibernate implements polymorphism and inheritance. Hibernate generated SQL maintains the portability of the application to all SQL databases. This HQL (SQL) allows create, retrieve, update and delete operations on POJO. This framework allows development of persistent Java classes which includes object oriented features like encapsulation, inheritance, polymorphism, and collections frameworks. Hibernate Query Language (HQL): This is an extremely powerful query language similar to SQL. HQL is an object oriented SQL. Like SQL using tables and columns, HQL uses classes and properties. This means HQL uses object models for relational operations. Hence, it is less verbose as compared to SQL. JDBC JDBC is a standard java API for accessing relational database used for persisting state. It connects to database executes SQL statements and gets result. JDBC can also be used in a distributed environment. JDBC makes connection with an underlying data source using Connection Interface. It uses following mechanisms for connections: DriverManager This class is the management layer of JDBC. DriverManager loads any JDBC 4.0 drivers when an application makes connection to a data source as a part of its initialization. Other JDBC drivers must be explicitly loaded. DataSource DataSource can be a legacy database, file system or some other source of data. It is preferred over DriveManager as it allows the underlying data source to be apparent to the application. The two important extensions of the DataSource interface are as follows: ConnectionPoolDataSource The connection pool names are configured in JNDI. They support caching and reusing of physical connections in a way improving application performance and scalability. XADataSource XAdataSource uses XAConnection objects internally. It establishes physical connection with the database using the given user name and password. The connection thus obtained can be used in distributed transaction. Session bean and JDBC: Java architecture implementing session beans along with JDBC, any persistence request is delegated to the JDBC tier by the session bean. Upon request, the session bean calls JDBC layer to obtain a reference to object of type javax.sql.DataSource  interface. The DataSource type object serves acts as a resource manager factory for  java.sql.Connection  objects (as outlined by JDBC specification) that implement connections to a database. Once a  Connection  object is retrieved, the following business logic and persistence code (reads, updates, looping resultset, transaction commit/rollback etc.) are JDBC code. JDBC drawbacks Java applications initially used the JDBC API to create/read/update/delete/ data into relational databases. The JDBC API makes direct use of SQL statements to perform data persistence activities (create, read, update, and delete). When JDBC code is implemented in Java classes, the business logic gets tightly coupled to the Java class. The JDBC embeddable java code relies on SQL, which is not uniform across databases. Thus the code is tightly coupled to one type of database and hence difficult to migrate. Transactional Support: By default, JDBC drivers work in auto-commit mode, where each database SQL (read, update) is an atomic transaction. It is very easy to disable auto-commit, execute SQL in batch mode (multiple queries/updates) and then commit or rollback the transaction. DAO-VO A typical DAO (Data Access object) provides an interface that describes its contract with external interfaces. This outlines a series of methods for data persistence (CRUD operations). Generally a DAO is defined with a base interface and its methods are implemented by entity classes. A VO (Value object) is a simple POJO to transfer the data across various tiers of Java architecture. JDO For every method Persistence Manager is obtained, a transaction is fetched, and operations are executed. By availing attach/detach and fetch-groups, persisted objects are made available outside the DAO layer in a seamless way. Hibernate and JPA JPA acts as an adapter over Hibernate. JPA provides the entire API to interact with Hibernate. In a way JPA acts as an abstraction between the java code and Hibernate. In such a architecture it is easy to replace Hibernate if need be. JCA Java EE Connector Architecture (JCA) is a Java-based technology solution for connecting application servers and enterprise information systems (EIS) as part of enterprise application integration (EAI) solutions. While JDBC is specifically used to connect Java EE applications to databases, JCA is a more generic architecture for connection to legacy systems. What improvements were made in EJB3.1 and JPA2 Improvements in EJB 3.1 With EJB 3.1, there is no need to define home/local interfaces. Now EJB can be defined simple with an annotation. Singleton beans were introduced with EJB 3.1. Singleton beans can be used for shared data at application level. Asynchronous EJB calls are now supported with @Asynchronous method-level annotation. Packaging and deployment can be directly done in a war file. Session beans with a local view can be accessed without a separate local business interface. EJB Timer Service enhancements are also included to support scheduling jobs; Stateful Session Bean timed objects and deployment-time timer creation. Embedded container: A new embeddable API is available for executing EJB components within a Java SE environment (for unit testing, batch processing, etc.). EJB Lite: This definition of a lightweight subset of functionalities can be provided within Java EE Profiles (such as the Java EE Web Profile). Portable JNDI name: The syntax for looking up EJB components is now specified. Example: A Stateless EJB @Stateless public class CustomerEJB { @PersistenceContext(unitName = customerPU) private EntityManager em; public Customer findCustById(Long id) { return em.find(Customer.class, id); } public Customer createCust( Customer cust) { em.persist(cust); return cust; } } Improvements in JPA 2.0 Collections of basic types. Collections of embeddable. A persistent ordering is now maintained using the @OrderColumn annotation. Orphan removal that allows removal of child object when parent object is removed. Pessimistic locking has also been introduced along with optimistic locking. Foreign key mapping were introduced with JPA 2.0 for unidirectional one-to-many relationships. Improved support for maps (java HashMaps). Criteria query API which allows queries to be constructed in an object-oriented manner. Improvements in JPQL syntax. JPA 2.0 allows nesting of embeddable objects into other embeddable objects and has entity relationships. JPA 2.0 Example: @Entity @NamedQuery(name = findAllCust, query= select c from Customer c) public class Customer implements Serializable { @Id @GeneratedValue private Long id; @Column(name = cust_name) private String custName; public Customer() { } //à ¢Ã¢â€š ¬Ã‚ ¦.Get and set methods @Override public String toString(){ StringBuilder sb = new StringBuilder(100); sb.append(id : );sb.append(id);sb.append( ; ); sb.append(custName : );sb.append(custName);sb.append( ; ); return sb.toString(); }

Microbiology for Environmental Engineering

Microbiology for Environmental Engineering By Georgios Tzelepis Microorganisms play a major role in controlling water and waste quality and every biological process is based on the action of microorganisms. Bacteria constitute an important group of microorganisms which are directly related to Environmental Engineering because of their crucial role in wastewater treatment. They are single celled prokaryotic organisms with a structurally and functionally simple form and various shapes, such as spherical, rod-shaped or spiral. One main characteristic of the bacterial cell is the lack of unit membrane system with exception the cytoplasmic membrane. The identification of bacteria is based on a number of different criteria including their morphological (shape, size), physiological and genetic characteristics. Their reproduction is based on the binary split with formation time of about 20 minutes. Bacteria are sensitive to pH changes and they survive under neutral conditions, although some of them can survive in a highly acidic environment. Regarding th eir survival temperature, they are divided into psychrophilic, mesophilic and thermophilic. Bacteria are very sensitive to temperature changes and they have an optimum growth temperature. (Darakas, 2016) Bacteria have the capacity to degrade the organic substances (pollutants) and this is the reason why they are the most important group of organisms in terms of the public health engineering, since biological waste water treatment processes are based on their activities. The assimilation of pollutants is mainly achieved by the biological self-cleaning of the water thanks to microorganisms and specifically bacteria. The main three points of interest in the wastewater treatment is the microorganisms (bacteria), the included organic matter which constitutes food for microorganisms and the oxygen which is necessary for the energy and survival of microorganisms.    Generally, the metabolic diversity of organisms, and more specifically of bacteria, firstly depends on the energy source. Energy is important for the chemical reactions and is obtained from environmental sources. When the sources are chemicals, the species are called chemotrophs, while when the energy is derived from the light they are called phototrophic species. However, some bacteria have the ability to use both energy sources based on conditions. Second classification is based on the carbon source. When they are organic compounds they are called chemoheterotrophs or photoheterotrophs respectively. Otherwise when inorganic compounds are used, bacteria are called chemoautotrophs or photoautotrophs. Finally, chemotroph bacteria which metabolise organic chemicals for energy are called chemoorganotrophs. Contrariwise, those that use inorganic chemicals are called chemolithotrophs. There are two basic types of metabolism for chemoorganotrophs; fermentation, in which the metabolism of the substrate is without external oxidizing agent, and respiration, in which there is an external oxidizing agent. Both types of metabolism can convert a primary source of energy to one which can be used by the cells. 2.1.1 Carbon source Bacteria that use carbon dioxide for the majority (or all) of their carbon requirements are called autotrophs. The obligate autotrophs that are able to use only CO2 as a source of carbon use simple energy substrates and they are either chemolithotrophs or photolithotrophs. (Singleton, 2005) In autotroph bacteria carbon dioxide from the environment is used to form complex compounds, but also there is the situation that carbon dioxide is incorporated in these compounds and called fixed. There are two common pathways for this fixation, the Calvin cycle and the reductive TCA cycle. Autotrophs are able to thrive in very harsh environments, such as deep sea vents, due to their lack of dependence on outside sources of carbon other than carbon dioxide. (Yates et al., 2016) On the other hand, most of the known species of bacteria are heterotrophic, both aerobic and anaerobic. They use as a main source of carbon complex carbon compounds derived from other organisms, with the most significant the glucose, alcohol, and organic acids. However, there are specialised heterotrophic bacteria capable also of decomposing cellulose (actinomycetes), keratin, hydrocarbons, and other substances. Heterotrophs are only able to thrive in environments that are capable of sustaining other forms of life due to their dependence on these organisms for carbon sources. (Lester Birkett, 1999) 2.2 Energy source Microorganisms, and more specifically bacteria, require food to obtain energy. Phototrophic bacteria are mostly aquatic organisms and obtain energy using radiant energy (light), usually via photosynthesis. This happens through specialized pigments that they contain in order to form energy molecules. Generally, photosynthetic bacteria can be divided in two categories, these who accomplish the photosynthesis with production of oxygen (aerobically) and those without (unaerobically). (Singleton, 2005) Chemotrophs are organisms that obtain their energy by metabolisng chemicals from the environment, through the oxidation of inorganic molecules, such as iron and magnesium. They are divided in two different categories, chemoautotrophs and chemoheterotrophs, with their difference already been described. (Boundless, 2016) Carbon source of heterotrophic bacteria can be either soluble and colloidal organics of untreated waste (BOD) or endogenous carbon microorganisms, i.e. the carbon putrescent dead cells or methanol (CH3OH), which is the best organic substrate to the denitrification. (Darakas, 2016) 2.3 Electron acceptor As mentioned, all the bacterial cells have to convert a primary source of energy into forms that can be used. Some cells can convert a primary energy source to an electrochemical form which consists of a gradient of ions between the two surfaces of cytoplasmic membrane. Chemotroph and phototroph bacteria form high-energy compounds from a primary energy source using different techniques. (Singleton, 2005) Respiration is a type of metabolism in which a substrate is metabolized with the help of an external oxidizing agent. Oxygen can work as the exogenous oxidizing agent having aerobic respiration, or organic oxidizing agents can be used instead in an anaerobic respiration. Despite the fact that the oxidizing agent can be inorganic or organic, in chemoorganotrophs, the substrate is always an organic compound. (Singleton, 2005) Oxygen is the final electron acceptor for the aerobic respiration. The sugar is completely broken down to carbon dioxide and water, yielding a maximum of 38 molecules of ATP per molecule of glucose. Electrons are transferred to oxygen using the electron transport chain (ETC), a system of enzymes and cofactors located in the cytoplasmic membrane and arranged so that the passage of electrons down the chain is coupled with the movement of protons (hydrogen ions) across the membrane and out of the cell. ETC induces the movement of positively charged hydrogen ions to the outside of the cell and negatively charged ions to its interior. This ion gradient results in the acidification of the external medium and an energized plasma membrane with an electrical charge of 150 to 200 millivolts. The generation of ion gradients is a common aspect of energy generation and storage in all living organisms. The gradient of protons is used directly by the cell for many processes, including the active tr ansport of nutrients and the rotation of flagella. The protons also can move from the exterior of the cell into the cytoplasm by passing through a membrane enzyme called the F1F0-proton-translocating ATPase, which couples this proton movement to ATP synthesis. (Kadner Rogers, 2015) Bacteria that are able to use respiration produce far more energy per sugar molecule than do fermentative cells, because the complete oxidation of the energy source allows complete extraction of all of the energy available. (Kadner Rogers, 2015) Respiration can also occur under anaerobic conditions. Anaerobic respiration uses external oxidizing agents such as nitrate (NO3), nitrite (NO2), sulfate (SO42), or fumarate in place of oxygen. Depending on the different types or conditions, the electron donor (substrate) used by chemoorganotrophs in anaerobic respiration is of various organic compounds. The energy yields available to the cell using these acceptors are lower than in respiration with oxygen, but they are still substantially higher than the energy yields available from fermentation. The utilization of CO2as a terminal electron acceptor is limited to a group of bacteria called methanogens and this process requires a strongly reduced environment. This procedure produces methane (CH4) which can be a problem in some instances like landfill sites. (Maier, 1999) All the bacteria have an optimum growth temperature where their growth is faster, while they also have a specific range of temperature into which they can only grow. Most of the bacteria are mesophilic and they grow in temperatures between 15 and 45 degrees of Celsius. Thermophilic are bacteria with growth temperature over 45 degrees of Celsius, while psychrophilic are the bacteria with growth temperature under 15 degrees. 3.1 Low temperature It is well known that bacteria as well as various other forms of life survive and thrive optimally in moderate conditions of temperature, pressure, pH and other environmental parameters. However, there is also evidence of bacteria life in extreme environments. For example bacteria were found to exist in the very acidic river Rio Tino while also bacteria were detected in subzero environments like in Lake Vostok even in depth of 3600 meters, below the surface ice. (Chattopadhyay Sengupta, 2013) At low temperature, bacteria are challenged with a number of difficulties due to decrease in the rate of biochemical reactions that sustain the life. Bacteria taken from low temperature environments were found with increased branched chain, short chain, anteiso and unsaturated fatty acids. They were also found to synthesize more cis fatty acids in preference to trans fatty acids. All these factors are contributing in the increase of membrane fluidity. Moreover, in order to adjust with the low enthalpy and the reduced atomic and molecular motions at low temperature, they achieve flexibility through reduction in strength and number of non-covalent interactions. Finally a high level of post-transcriptional modification of t-RNA by dihydrouridine also has a major role in psychrophiles. Dihydrouridine unsettles the stacking that stabilizes the RNA. (Chattopadhyay Sengupta, 2013) 3.2 High temperature Thermophilic bacteria are common in soil and volcanic habitats and have a limited species configuration. Examination of metabolic pathways and regulatory mechanisms in thermophiles proves that thermophilic bacteria have almost the same properties commonly found in mesophilic bacteria, with the main difference being specific molecular mechanisms, important in high temperature biological stability and activity. As a consequence of growth at high temperature and unique macromolecular properties, thermophilic bacteria can possess high metabolic rates, physically and chemically stable enzymes than similar mesophilic species. Thermophilic processes appear more stable, rapid and facilitate reactant activity and product recovery. Analysis of important biomolecules in thermophilic bacteria has revealed subtle structural differences in proteins, nucleic acids and lipids. Some of these differences have not been observed in mesophilic bacteria. For instance the membrane lipids of extreme thermop hiles contain more saturated and straight chain fatty acids than mesophiles. This allows thermophilic bacteria to grow at higher temperatures by providing the correct degree of fluidity required for membrane function. Finally the explanation for high temperature stability of tRNA in Thermus species is that Thermus transfer RNA contains more guanine plus cytosine bases in the specific base-paired region, which provides greater hydrogen bonding and increased thermal stability. Also, the base-paired region in tRNAs from Thermus contains more thiolated thymidine which provides a stronger stacking force inside the molecule. (Zeikus, 1979) The restoration, maintenance and protection of the environment with the help of biological agents in general and bacteria more specifically are significantly important in terms of sustainability in the environment. Hence, in many cases, bacteria and environmental engineering go hand in hand and both are interdependent on each other. Their main connection is the removal and treatment of the wastes, solid or liquid, from various sources like the industrial, domestic and other. There are many examples of the use of bacteria especially in waste and wastewater treatment, where some useful characteristics of bacteria are used.   Ã‚   4.1 Wastewater treatment Biological treatment is one of the most widely used removal methods as well as for partial or complete stabilization of biologically degradable substances in wastewaters. General characteristics of wastewaters are measured in terms of Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), and Volatile Suspended Solids (VSS). Bacteria provide the largest component of the microbial community in all biological wastewater treatment processes, and numbers in excess of 106 bacteria/ml of wastewater are frequently encountered. 4.1.1 Activation Sludge Activated sludge is a process that has been adopted worldwide as a secondary biological treatment for domestic wastewaters. In the activated sludge process the incoming wastewater is mixed and aerated with existing biological sludge (microorganisms). Organics in the wastewater come into contact with the microorganisms and are utilized as food and oxidized to CO2, and H2O. The microorganisms using the organics as food they reproduce, grow, and die. While the microorganisms grow, are mixed together by the movement of air so individual organisms join an active mass of microbes called activated sludge. The wastewater flows continuously into an aeration tank where air is injected to mix the activated sludge with the wastewater and to supply oxygen needed for microbes to breakdown the organic materials. This mixture of activated sludge and wastewater in the aeration tank is called mixed liquor suspended solids and mixed liquor volatile suspended solids. The mixed liquor is sent to the slud ge handling disposal (second part of activation sludge method). A part of this mass precipitates while the rest flows back to the aeration tank in order to maintain sufficient microbial population levels. This is the called activated sludge. The microorganisms in activated sludge generally are composed of 70 to 90% organic and 10 to 30% inorganic matter. The microorganisms generally found in activated sludge consist of bacteria (mostly), fungi and protozoa. 4.1.2 Nitrogen and Phosphorus removal Nitrogen and phosphorus are two essential elements in terms of the waste treatment. The nitrogen compounds and the phosphates existing in wastewaters are very important for the survival of the bacteria although they should be removed in order to avoid problems of deoxygenation and eutrophication in the final recipient. (Bitton, 2010) Nitrification The principal organisms involved in nitrification processes belong into two categories, Nitrosomonas and Nitrobacter. These bacteria are considered to be strictly autotrophs since they derive energy for growth and synthesis from the oxidation of inorganic nitrogen and carbon (CO2) compounds. Nitrosomonas catalyse oxidation of ammonia to nitrite using molecular oxygen, while Nictobacter further oxidize nitrite to nitrate using oxygen derived from the water molecule. It should be mentioned that some some soluble forms of c-BOD can inhibit the activity of nitrifying bacteria since they are able to enter the cells of nitrifying bacteria and inactivate their enzyme systems. (Horan, 1989) Denitrification Denitrification is a process by which certain species of bacteria under anoxic conditions reduce nitrate nitrogen to the gaseous end-products of N2, NO, or N2O which can then escape from solution to the atmosphere. Unlike other nitrogen compounds, the gaseous forms of nitrogen have no significant effect on environmental quality. The presence of oxidized nitrogen and organic carbon are essential properties for denitrification to proceed. Denitrifying bacteria are composed of heterotrophic organisms. The most common denitrifying bacteria are Bacillus denitrijicans, Micrococcus denitrijicans and more. (Horan, 1989) Phosphorus removal The anaerobic-oxic process (most commonly used), consists of a modified activated sludge system that includes an anaerobic upstream of the conventional aeration tank. During the anaerobic phase, inorganic phosphorus is released from the cells as a result of polyphosphate hydrolysis. The energy liberated is used for the uptake of BOD from wastewater. (Bitton, 2010)Removal efficiency is high when the BOD/phosphorus ratio exceeds 10. During the aerobic phase, soluble phosphorus is taken up by bacteria that synthesize polyphosphates using the energy released from BOD oxidation. The anaerobic-oxic process results in BOD removal and produces sludge which is rich in phosphorus. The key features of this process are the relatively low solid retention time and high organic loading rates. (Cheremisinoff, 1997) 4.1.3 Anaerobic Digestion Major applications of anaerobic digestion are the stabilization of concentrated sludges produced from the treatment of especially industrial wastes. The digestion is a complex biochemical process in which several groups of anaerobic and facultative organisms again simultaneously absorb and break down organic matter and can be described as a two-phase process. In the first phase, acid-forming organisms convert the complex organic substrate to simple organic acids. Little change occurs in the total amount of organic material in the system, with decrease in ph . Second phase involves conversion of the organic acids to principally methane and carbon dioxide. The anaerobic process is essentially controlled by the methane producing bacteria. Methane formers are very sensitive to pH, substrate composition, and temperature. If the pH drops below 6,methane formation stops, and there is no decrease in organic content of the sludge. One characteristic of the methane bacteria is that they are hi ghly active in the mesophilic and thermophilic ranges. (Cheremisinoff, 1997) 4.2 Solid Waste Treatment 4.2.1 Composting Composting is the biological decomposition and stabilization of organic substrates. Each gram of decaying compost contains millions of beneficial microorganisms that work to break down organic matter. Of the microorganisms present, 80 to 90 percent are bacteria, including actinomycetes and aerobic bacteria. Aerobic are separated in three different varieties, each of which is active at different phases of the decomposition process. Psychrophilic bacteria (during winter) work on the initial organic matter, at temperatures around 12 degrees Celsius. These bacteria raise the temperature to 20 C, at which time, the mesophilic bacteria take over. These bacteria work at moderate to warm temperatures between 20 and 38 C. At 38 C, the thermophilic bacteria take over, raising the temperature to 70 C. Once this happens, the process starts over again with the addition of new materials. Actinomycete bacteria appear during the late stages of composting to clean up remaining materials that are diff icult for aerobic bacteria to break down. They are responsible for breaking down cellulose, proteins, lignin and starches. References Bitton G., (2010), Activated Sludge Process, in Wastewater Microbiology, 4th Edition, Hoboken, NJ, USA, John Wiley Sons, Inc. Boundless, (2016), Chemoautotrophs and Chemoheterotrophs, Boundless Microbiology, Available from: https://www.boundless.com/microbiology/textbooks/boundless-microbiology-textbook/microbial-metabolism-5/types-of-metabolism-41/chemoautotrophs-and-chemoheterotrophs-285-6153/, [Accessed: 13 January 2017] Chattopadhyay M. and Sengupta D., (2013), Metabolism in bacteria at low temperature: A recent study report., Biosciences, 31, 2, 157-165. Available from: https://www.researchgate.net/publication/236674848_Metabolism_in_bacteria_at_low_temperature_A_recent_report , [Accessed: 10 January 2017] Cheremisinoff N. P., (1997), Biotechnology for Industrial and municipal wastes, in Biotechnology for Waste and Wastewater Treatment, 1-36 Darakas E., (2016), Environmental Engineering: Process of water and wastewater treatment, Thessaloniki, Sofia Publisher. Horan N., (1989), Biological Wastewater Treatment Systems: Theory and Operation., Chichester, England, Wiley Blackwell. Hurst, C.J. et al., (2002), Manual of Environmental Microbiology, 2nd Edition, Washington, ASM Press. Kadner R. J. and Rogers K., (2015), Bacteria. Available from: https://www.britannica.com/science/bacteria/Salt-and-water. [Accessed: 23 December 2017] Lester, J.N. Birkett, J.W., (1999), Microbiology and Chemistry for Environmental Engineers, London, E. F.N. Spon. Maier, E.M. et al, (1999), Environnemental Microbiology, Academic Press Singleton P., (2005), Bacteria in Biology, Biotechnology and Medicine, 6th Edition, Wiley Smith S. R., (2016), Bacteria, Lecture Slides for the course of Microbiology for Environmental Engineering; MSc of Environmental Engineering, London, Imperial College London. Traumann N. and Olynciw E., (1996), Compost Microorganisms, Cornell Waste Management Institue, New York, Available from: http://compost.css.cornell.edu/microorg.html, [Accessed: 10 January 2017]. Yates V. M., Nakatsu C. H., Miller R. V., Pillai S. D., (2016), Manual of Environmental Microbiology, 4th Edition, ASM Press Zeikus, J.G., (1979), Thermophilic bacteria: ecology, physiology and technology., Enzyme and Microbial Technology, 1, 4, 243-252. Available from: http://www.sciencedirect.com/science/article/pii/0141022979900437?via%3Dihub, [Accessed: 27 December 2016]

Their Eyes Were Watching God Essays - Janies Life and the Pear Tree :: Their Eyes Were Watching God Essays

Their Eyes Were Watching God - Janie's Life and the Pear Tree          Their Eyes Were Watching God is a story centered on the idea of life cycles.   The experiences that Janie faces and struggles through in her life represent the many cycles that she has been present for.   Each cycle seem to take place with the start of each new relation ship that she faces.   Each relationship that Janie is involved in not just marriages, blooms and withers away like the symbol of Janie's life the pear tree from her childhood.           Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Janie's Grandmother is the first bud on her tree.   She raised Janie since she was a little girl.   Her grandmother is in some respects a gardener pruning and shaping the future for her granddaughter.   She tries to instill a strong belief in marriage.   To her marriage is the only way that Janie will survive in life.   What Nanny does not realize is that Janie has the potential to make her own path in the walk of life.   This blinds nanny, because she is a victim of the horrible effects of slavery.   She really tries to convey to Janie that she has her own voice but she forces her into a position where that voice is silenced and there for condemning all hopes of her Granddaughter become the woman that she is capable of being.           Ã‚  Ã‚   The affect of Nanny is the marriage to her first of three husbands, Logan.   He is a man that sees no wife in his relationship with Janie he sees a worker.   The intelligence of Janie to realize this is a prime example of the capabilities that Janie possesses as an independent woman.   Logan is the pollution to Janie's tree of life.   He is good for one thing and that is delaying the inevitable; delaying Janie from realizing that she can be a woman with an inelegant thought not just a good house worker.   He prevents the self-sufficient woman in Janie from reaching its potential.         Ã‚  Ã‚   The next cycle is that of Joe Starks.   The role of this marriage is of a different nature.   Janie no longer is a house slave.   She chooses to take the role of a trophy wife in the times that this takes place in.

Essay on the Artist as Hero in A Portrait of the Artist As a Young Man

The Artist as Hero in A Portrait of the Artist As a Young Man  Ã‚        Ã‚   A Portrait of the Artist As a Young Man by James Joyce is a partly autobiographical account of the author's life growing up.   The novel chronicles the process through which the main character, Stephen, struggles against authority and religious doctrine to develop his own philosophies on life.   Stephen is not necessarily rebelling against God and his father as much as he is finding his own person, creating his own life.   He is an artist, not because of the outcome of his life, but because of the process he goes through to achieve that outcome.   The artist is a hero because of the sacrifices he makes, the persecution he endures, and the risks he undertakes merely to set foot towards his vision.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Joyce demonstrates that whether or not Stephen achieved his vision is insignificant to the actual journey itself.   First of all, the novel concludes not with the outcome of Stephen's life but with the beginning stages of his journey.   "Old father, old artificer, stand me now and ever in good stead," he writes in the last sentence of the novel.   Joyce purposefully ends the book before Stephen's sets off, to emphasize that the process he undergoes to reach that point where he can reject the very foundation upon what his life was based is where the importance lies.   The infamous hell scene spans over twenty pages not to frighten the reader as much as to show how difficult it is to even become an artist and fight conformity.   All process towards breaking away is lost after the preacher's sermon on hell, as shown in the following passage: He beat his breast with his fist humbly, secretly under cover of the wooden armrest.   He would be at one with others... ...d for his art, seeing that his religion is no good for his heart, he forges a new life and religion for his own, fulfilling his destiny as an artist.    Works Cited Beebe, Maurice.   "The Artist as Hero." James Joyce, A Portrait of the Artist as a   Young Man:   Text, Criticism, and Notes.   Ed.   Chester G. Anderson.   New   York:   Penguin, 1968.   340-57. Ellmann, Richard.   "The Limits of Joyce's Naturalism." Sewanee Review 63   (1955):  Ã‚   567-75. Givens, Seon, ed.   James Joyce:   Two Decades of Criticism. New York:   1948. 2nd ed.   1963. Joyce, James.   A Portrait of the Artist as a Young Man.   The Portable James Joyce.   Ed.  Ã‚   Harry   Levin.   New   York:   Penguin, 1976. Power, Arthur.   Conversations with James Joyce.   Ed. Clive Hart.   London:  Ã‚   Millington, 1974. Wright, David G.   Characters of Joyce.   Dublin:   Gill and Macmillan, 1983.       Essay on the Artist as Hero in A Portrait of the Artist As a Young Man The Artist as Hero in A Portrait of the Artist As a Young Man  Ã‚        Ã‚   A Portrait of the Artist As a Young Man by James Joyce is a partly autobiographical account of the author's life growing up.   The novel chronicles the process through which the main character, Stephen, struggles against authority and religious doctrine to develop his own philosophies on life.   Stephen is not necessarily rebelling against God and his father as much as he is finding his own person, creating his own life.   He is an artist, not because of the outcome of his life, but because of the process he goes through to achieve that outcome.   The artist is a hero because of the sacrifices he makes, the persecution he endures, and the risks he undertakes merely to set foot towards his vision.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Joyce demonstrates that whether or not Stephen achieved his vision is insignificant to the actual journey itself.   First of all, the novel concludes not with the outcome of Stephen's life but with the beginning stages of his journey.   "Old father, old artificer, stand me now and ever in good stead," he writes in the last sentence of the novel.   Joyce purposefully ends the book before Stephen's sets off, to emphasize that the process he undergoes to reach that point where he can reject the very foundation upon what his life was based is where the importance lies.   The infamous hell scene spans over twenty pages not to frighten the reader as much as to show how difficult it is to even become an artist and fight conformity.   All process towards breaking away is lost after the preacher's sermon on hell, as shown in the following passage: He beat his breast with his fist humbly, secretly under cover of the wooden armrest.   He would be at one with others... ...d for his art, seeing that his religion is no good for his heart, he forges a new life and religion for his own, fulfilling his destiny as an artist.    Works Cited Beebe, Maurice.   "The Artist as Hero." James Joyce, A Portrait of the Artist as a   Young Man:   Text, Criticism, and Notes.   Ed.   Chester G. Anderson.   New   York:   Penguin, 1968.   340-57. Ellmann, Richard.   "The Limits of Joyce's Naturalism." Sewanee Review 63   (1955):  Ã‚   567-75. Givens, Seon, ed.   James Joyce:   Two Decades of Criticism. New York:   1948. 2nd ed.   1963. Joyce, James.   A Portrait of the Artist as a Young Man.   The Portable James Joyce.   Ed.  Ã‚   Harry   Levin.   New   York:   Penguin, 1976. Power, Arthur.   Conversations with James Joyce.   Ed. Clive Hart.   London:  Ã‚   Millington, 1974. Wright, David G.   Characters of Joyce.   Dublin:   Gill and Macmillan, 1983.      

Course note. Organizational behavior Essay

ORGANIZATIONAL BEHAVIOR To distinguish and compare the various concepts and models of organizational behavior in a manner that-will help day-to-day conceptual, human, and communication skills of the students. To develop skills in diagnosing situations by encouraging them to participate actively in cases, topics, illustrations, and incidents that serve to provide operational meaning to the abstract concepts and models of organizational behavior. To assess and evaluate why certain events and behavioral processes occur in organizations and how, as managers, they can best affect the behavior of subordinates as well as other managers. COURSE DESCRIPTION This course utilizes the contingency approach to understanding organizational behavior. This approach seeks to understand the interrelations among the various parts of the organization. Each department, work group, or manager can be analyzed separately or as a unit related to other departments, work groups, or managers. The contingency approach requires that managers diagnose each situation confronting them, and then apply, as needed, the concepts and approaches presented in the course. These concepts and approaches will help the students to develop the knowledge and skills necessary to understand what is happening in an organization and what can be done about it. 1 ORGANIZATIONAL BEHAVIOR Week TOPIC Introduction to Organizational Behavior: ï‚ · What is organizational behavior? ï‚ · Organizational behavior and management. ï‚ · Challenges for organizational behavior and management. Course Outcomes CO1 Delivery Mode Lecture Discussion Assessment Tools ï‚ · Quiz ï‚ · Test Rubrics Na Na INDIVIDUAL PROCESSES Personality and Perception ï‚ · The nature of personality. ï‚ · Model of personality. ï‚ · Personality traits. ï‚ · The nature of perception. ï‚ · Perception process ï‚ · Attribution theory. Learning and Motivation ï‚ · The nature of learning. ï‚ · Learning theories. ï‚ · The nature of work motivation. ï‚ · Motivation theories ï‚ · ï‚ · CO2 Lecture Discussion ï‚ · Quiz ï‚ · Test ï‚ · Case Study Analysis Na Na √ CO2 Lecture Discussion ï‚ · Quiz ï‚ · Test Na Na ï‚ · Case Study Analysis √ Quiz 1 Mini Case 2 ORGANIZATIONAL BEHAVIOR GROUP PROCESSES Work Groups and Teams ï‚ · The nature of work groups and teams. ï‚ · Formation and development of groups. ï‚ · Effective Work Groups and Teams. CO3 Lecture Discussion ORGANIZATIONAL PROCESSES Leadership ï‚ · Introduction to leadership. ï‚ · Leadership theories. CO3 Communication ï‚ · What is communication? ï‚ · The functions of communication. ï‚ · The communication process. Lecture Discussion ï‚ · Quiz ï‚ · Test ï‚ · Case Study Analysis ï‚ · Quiz ï‚ · Test ï‚ · Case Study Analysis ï‚ · Quiz ï‚ · Test ï‚ · Case Study Analysis Na Na √ Na Na √ Na Na √ ï‚ · Quiz II ï‚ · Mini Case Decision Making ï‚ · What is decision making? ï‚ · Types of decision making. ï‚ · The decision making process. ï‚ · Group decision making. CO3 Lecture ï‚ · Test Discussion ï‚ · Case Study Presentation Analysis ï‚ · Group Presentation Na √ √ 3 ORGANIZATIONAL BEHAVIOR ï‚ · Test 1 (2hours) INTERGROUP RELATIONS IN THE ORGANIZATIONAL CONTEXT Organizational Culture ï‚ · The concept of organizational culture. ï‚ · Determinants of organizational culture. ï‚ · Managing organizational culture. ï‚ · ï‚ · CO3 ï‚ · Test ï‚ · Case Study Analysis ï‚ · Project Paper Na Lecture ï‚ · Quiz Discussion ï‚ · Test Presentation ï‚ · Case Study Analysis ï‚ · Group Presentation Na Na √ ï‚ · Quiz ï‚ · Test ï‚ · Case Study Analysis ï‚ · Group Presentation Na Na √ Lecture Discussion √ √ Quiz III Mini Case Power, Politics, and conflict ï‚ · The nature of power and politics. ï‚ · Sources of power. ï‚ · What is organizational conflict. ï‚ · Model of organizational conflict. ï‚ · Conflict management techniques. Organizational Change ï‚ · What is organizational change? ï‚ · Organizational change theory. ï‚ · Forces for and resistance to organizational change. ï‚ · Managing change CO3 √ √ 4 ORGANIZATIONAL BEHAVIOR Social Responsibility and Managerial Ethics ï‚ · What is social responsibility? ï‚ · Views of social responsibility. ï‚ · Arguments for and against social responsibility. ï‚ · What is managerial ethics. ï‚ · Factors that affect employee ethics. ï‚ · Ethics in international context. ï‚ · Improving ethical behavior. Lecture Discussion ï‚ · Test ï‚ · Case Study Analysis ï‚ · Project Paper Na √ √ Test 2 (2 hours) Group / Team Project Presentation Submission of Group /Team Project: (Latest Deadline – A week after the final class/lecture) 5 ORGANIZATIONAL BEHAVIOR TEACHING METHODOLOGY Lectures/Case Study Analysis/Discussions/Active Learning/Presentations/Projects ASSESSMENT 1. Test 2. Individual Assignments 3. Group Project 4. Final Assessment 10% 30% 30% 30% ———–100% ———— Total REFERENCES Main Reference: 1. Schermerhorn, J. R., Hunt, J. G., and Osborn, R. N. (2008). Organizational Behavior. New York: John Wiley & Sons, Inc. Supplementary References: 1. Asma Abdullah (2004). Going Glokal. Kuala Management (MIM). Lumpur: Malaysian Institute of 2. George, J. M. and Jones, R. J. (2008). Organizational Behavior (5th. Edition). New Jersey: Pearson Education, Inc. 3. Gibson, J., Ivancevich, J., Donnelly Jr. J., and Konoposke, R. (2005). Organizations: Behavior, structures, processes. Boston: Irwin McGraw-hill. 4. Nelson, D. L. and Quick, J. C. (2006). Organizational Behavior: Foundations, Realities, and Challenges (12th. edition). Ohio: South-Western College Publishing. Journals ï‚ · ï‚ · ï‚ · ï‚ · ï‚ · Journal of Organizational Behavior, Academy of Management Journal, Journal of International Business Studies, Journal of Occupational Psychology, Journal of Applied Psychology 6 ORGANIZATIONAL BEHAVIOR Journals 1. Harvard Business Review 2. Fortune Magazine 3. The Edge 4. Malaysian Business Review 5. World Executive Digest 6. The Economist 7. Other related journals 7 View as multi-pages

Neoplasm

A neoplastic growth is called a neoplasm . An abnormal proliferation of cells in a tissue or organ is referred to as Neoplasia meaning new growth in geek language. This research paper takes a brief   look at the definition, characteristics, symptoms, treatment and prevention of neoplasm a new and abnormal growth of tissue, which may be benign or cancerous. Generally   neoplasms form distinct masses, or tumors, but there are also many examples of neoplastic processes which are not grossly apparent, a common example being pre-cancerous lesions of the cervix, however, it is important to note that the term neoplasm is not the same as cancer because neoplasms can be either benign or malignant. It is however,   interesting to note that there is no single complete consensus in the biomedical community as to the exact biological definition of a neoplasm, although a statement credited to R.A. Willis a British oncologist is widely cited: â€Å"A neoplasm is an abnormal mass of tissue, the growth of which exceeds and is uncoordinated with that of the normal tissues, and persists in the same excessive manner after cessation of the stimulus which evoked the change†. Neoplastic tumors often contain more than one type of cell, but their initiation and continued growth is usually dependant on a single population of neoplastic cells which are clonal – that is, they are descended from a single progenitor cell. The neoplastic cells typically bear common genetic or epigenetic abnormalities which are not seen in the non-neoplastic stromal cells and blood-vessel forming cells, whose growth is dependant on molecular stimuli from the neoplastic cells. The demonstration of clonality is now considered by many to be necessary (though not sufficient) to define a cellular proliferation as neoplastic. Symptoms depend on the type and location of the tumor. For example, lung tumors may cause coughing, shortness of breath, or chest pain, while tumors of the colon can cause weight loss, diarrhea, constipation, iron deficiency anemia, and blood in the stool. Some tumors produce no symptoms, but symptoms that often accompany tumors include: Fever, Chills, Night sweats, Weight loss, Loss of appetite, Fatigue, and Malaise Like the symptoms, the signs of tumors vary based on their site and type. When a tumor is found, a biopsy is performed to determine if the tumor is benign or malignant. The biopsy may be a simple procedure or a serious operation depending on the location of the tumor. More recently, positron emission tomography (PET) scans have been used to visualize certain tumors types. Complete blood count (CBC), Blood chemistries,   Biopsy of the tumor , and Chest x-ray are other common tests that can be undergone by patients with malignant neoplasm. Treatment also varies based on the type of tumor, whether it is benign or malignant, and its location. If the tumor is benign (meaning it has no potential to spread) and is located in a â€Å"safe† area where it will not cause symptoms or disturb the proper functioning of the organ, sometimes no treatment is needed. Benign tumors of the brain may be removed because of their location or harmful effect on the surrounding normal brain tissue. Treating malignant neoplasms require surgery, radiation, chemotherapy, or a combination of these methods. In conclusion it should be noted that the risk of malignant tumors (cancer) can be reduced by eating a healthy diet, exercising regularly, not smoking or chewing tobacco, avoiding heavy alcohol consumption, maintaining a healthy weight, reducing sun exposure if you burn easily, and minimizing exposure to radiation and toxic chemicals. However, it is advisable that you call your healthcare provider if you notice any suspicious lumps or bumps on your body or if you notice a new or changing mole on your skin. Reference Willis RA, (1952). The Spread of Tumors in the Human Body. London, Butterworth & Co.