the immune system immune ; immunity ; disease ; bacteria ; viruses ; white ; cells ; lymph ; germs ; mucous ; mucus ; glands ; what is immunity? immunity ( say im - yoon - it - i ) means that you are protected against something. there are different kinds of immunity. this topic is about how different parts of our bodies work together to keep us from getting sick. immunity to some diseases is passed on from our mothers before we are born. immunisation ( having your ' shots ' ) helps our body ' s immune defence system protect us from diseases. body ' s immune system every body has an inbuilt immune system which protects it from diseases and germs. this system has a lot of different parts which work together to keep out any harmful germs, and attack and destroy any which manage to get inside your body - every day your body is exposed to millions of germs, and you do not get sick from them because of your immune system. - every time you do get sick because of a germ, your immune system works to get rid of it and then it remembers how to fight the infection if the same germ comes again. - usually the older you get, the more germs you become immune to. so, let ' s have a look at the immune system, starting from the outside of the body. the skin is the first line of defence in your immune system. you know how you put plastic wrap over leftovers to keep them fresh enough for later? well, your skin is like a plastic wrap to keep germs from getting into your body. - the epidermis ( outside layer of skin ) has special cells which warn the body about incoming germs. - glands in the skin also make substances that can kill some bacteria ( anti - bacterial chemicals ). this means you don ' t get infections on your skin unless your skin is damaged, such as by a cut or a graze. your nose, mouth and eyes are the next point of attack. - the mucous membranes which line the mouth, throat, lungs and bowel, act like a barrier to germs, just as the skin does. - saliva in the mouth and the tears which wash your eyes have special enzymes ( chemicals ) in them which break down the cell walls of many bacteria and viruses. - the mucous that is made in your nose, throat and lungs traps bacteria, viruses and dust. - acid in your stomach kills most germs


special enzymes ( chemicals ) in them which break down the cell walls of many bacteria and viruses. - the mucous that is made in your nose, throat and lungs traps bacteria, viruses and dust. - acid in your stomach kills most germs, and starts to digest your food. - lymph ( limf ) is a clear fluid that is very similar to blood plasma, the clear liquid in blood, but it carries only white blood cells, not red blood cells. - the lymph flows through all the parts of the body picking up fluid around cells and carrying it back to large veins near the heart. it also carries white blood cells to the places that they are needed. - some bacteria or viruses that have entered the body are collected by the lymph and passed on to the lymph nodes where they are filtered out and destroyed. lymph nodes are sometimes called glands. your doctor can often tell if you have an infection by checking out the lymph nodes ( glands ) in your neck and under your arms to see if they ' re swollen. if they are, it shows that they are working to get rid of bacteria or viruses. in your blood you have red blood cells and white blood cells, and in lymph there are white blood cells. there are several different types of white cells which work together to seek out and destroy bacteria and viruses. all of them start off in the bone marrow, growing from ' stem cells '. the disease - fighting white blood cells are specialists. some of the white blood cells are : - neutrophils ( say new - tro - fills ), which move around the body in the blood and seek out foreign material ( things that don ' t belong in your body ). - macrophages ( say mak - row - far - jes ) are the biggest blood cells. some live in different parts of the body and help to keep it clean, eg. in the lungs. others swim around cleaning up other white blood cells that have been damaged while doing their jobs, eg. cleaning up pus that has been caused by neutrophils when they work to clear out bacteria from a wound. - lymphocytes ( say lim - fo - sites ) work on bacterial and viral infections there are two different types : - b cells produce antibodies. each cell watches out for a particular germ, and when that germ arrives, the cell starts to produce more antibodies which begin the process of killing that germ


in digital imaging, there are 256 levels, or tonal values, ranging from black to white. black is level 0. white is level 255. of course, not all images ( e. g. extreme foggy, misty, atmospheric shots ) contain the full tonal range from black to white, but most do. the histogram ( levels ) is a graphical representation of the tonal values in an image. ideally, it should range from 0 to 255, with a good spread of tonal values throughout. if the histogram is bunched up towards the left, it indicates the image is under - exposed. note the crushed shadow detail. if bunched up towards the right, it ' s over exposed. note the blown - out highlights. if the black and white points are set incorrectly, the image will have a dull, flat, washed - out appearance. here they ' re wrongly set to 20 / 230. unless under instructions from a repro bureau or printer, you should not set the black / white points to anything other than 0 / 255. the printer may well adjust them later for technical reasons to do with repro, but don ' t try to guess what ' s required. it ' s true that some leeway is acceptable ( e. g. up to 5 % is usually ok ), but your images will lack visual impact if the black / white points are incorrect, so don ' t do this as a matter of course. in the vast majority of cases, it ' s best to set them to 0 / 255.


the environmental impact of electric vehicles has been in the media for some time. now comes news that electric vehicles can also impact running the home. an exhibit at the georgian college auto show, in barrie, ontario, demonstrates the integration of electric vehicles into the home by using the latest smart grid technologies. the display, which is run by nissan and powerstream, shows how an electric vehicle such as the nissan leaf can help power the home by converting energy stored in the car ’ s batteries to residential use through a system called vehicle to home ( v2h ). with energy stored in its 24kw lithium - ion battery, a fully charged nissan leaf can provide enough electricity to run a typical residential canadian home for a full day. the leaf to home electricity - supply system is gathering attention as a new form of infrastructure, as well as contributing factor to energy saving and alternative energy use. powerstream, ontario ’ s second - largest community - owned company, began working on the project after taking delivery of nissan ’ s fully - electric leaf vehicle. “ the powerstream / nissan display proves how smart connections between the grid, the home and the car can help us improve the way energy is managed, consumed – and conserved, ” said markham mayor frank scarpitti, who is chairman of the board at powerstream. “ the collaboration between nissan and powerstream illustrates the dramatic changes underway in technology and how two industry leaders can collaborate to benefit consumers. ” studies have shown that cutting off one household from the network when power demands are their highest can significantly contribute towards the stable supply of power throughout the grid. the nissan / powerstream v2h system demonstrates leading - edge technologies and the future capabilities of smart grid and the benefit to consumers. cnw group / nissan canada nissan canada and powerstream demonstrate the nissan ‘ leaf to home ’ charging system for first time in canada at the georgian college auto show in barrie. earlier this week in japan, nissan introduced the ev power station, an electric - vehicle charging station developed by nichicon corporation. the ev power station can fully recharge the leaf ’ s high - capacity batteries in as little as four hours, approximately half the time required by conventional chargers. “ the public debut of v2h in canada today will drive new advancements and collaboration in the auto industry of tomorrow, ” said nissan canada president allen childs. “ v2h will foster literal connections, such as those between vehicles, infrastructure, the internet, and the nation ’ s electrical grid, and the connections and relationships between engineers who are


when i was learning carpentry from a master carpenter, i tried to do something with a tool close at hand instead of going to get the correct tool for the job. of course, i butchered the piece of wood and eventually had to get the right tool, which got the job done in a fraction of the time that i wasted with the convenient - to - reach tool. the same lesson applies to power quality tools, which range from a simple screwdriver to a $ 24, 000, 32 - gigahertz ( ghz ) spectrum analyzer. not only can you waste time and not get the answer you are looking for, you might even be led to the wrong answer using the wrong tool for the task. before going into the variety of tools available, here ’ s a quick safety reminder. always assess the hazards and skills required for the task, and ensure you or whoever is doing it is a “ qualified person ” per the national electrical code definition. ensure all personnel within the possible hazard area wear the proper personal protective equipment per nfpa 70e and other local requirements. and wherever possible, make connections on de - energized circuits only. even something as simple as taking a panel cover off to tighten a screw can be disastrous. accidents don ’ t always happen to someone else. on the low end of the price range is an item in everyone ’ s tool kit : a digital multimeter ( dmm ). a dmm can measure a number of steady - state power quality phenomena, such as voltage imbalance. it can also be used to find voltage drops across contacts and other devices that should have very low drops. excessive neutral - to - ground voltage is often a steady - state condition. clamp - on power meters are slightly more expensive ( $ 300 – $ 3, 000 ) but used similarly. though only single - phase, they can be useful for current imbalance and power factor, and many have limited harmonic measuring capabilities. be wary of the 3 assumptions some meters make, which contend that all three phases are identical and, therefore, give you three - phase answers with a simple multiplication. also, most clamp - on meters use current transformers that cannot measure ( or tolerate ) direct current ( dc ). power loggers generally have capabilities similar to power meters but can take unattended readings for extended periods. they are useful for finding time - correlated problems, such as the voltage drops at a certain time each day. several manufacturers offer both single - and three - phase loggers ( $


focus on economic data : consumer price index and inflation, october 19, 2011 glossary terms from : one of many choices or courses of action that might be taken in a given situation. any activity or organization that produces or exchanges goods or services for a profit. consumer price index ( cpi ) a price index that measures the cost of a fixed basket of consumer goods and services and compares the cost of this basket in one time period with its cost in some base period. changes in the cpi are used to measure inflation. people who use goods and services to satisfy their personal needs and not for resale or in the production of other goods and services. spending by households on goods and services. the process of buying and using goods and services. a sustained decrease in the average price level of all the goods and services produced in the economy. a severe, prolonged economic contraction. the central bank of the united states. its main function is controlling the money supply through monetary policy. the federal reserve system divides the country into 12 districts, each with its own federal reserve bank. each district bank is directed by its nine - person board of directors. the board of governors, which is made up of seven members appointed by the president and confirmed by the senate to 14 - year terms, directs the nation ' s monetary policy and the overall activities of the federal reserve. the federal open market committee is the official policy - making body ; it is made up of the members of the board of governors and five of the district bank presidents. something a person or organization plans to achieve in the future ; an aim or desired result. tangible objects that satisfy economic wants. spending by all levels of government on goods and services ; includes categories like military, schools and roads. individuals and family units that buy goods and services ( as consumers ) and sell or rent productive resources ( as resource owners ). payments earned by households for selling or renting their productive resources. may include salaries, wages, interest and dividends. a rise in the general or average price level of all the goods and services produced in an economy. can be caused by pressure from the demand side of the market ( demand - pull inflation ) or pressure from the supply side of the market ( cost - push inflation ). money paid regularly, at a particular rate, for the use of borrowed money. the quantity and quality of human effort available to produce goods and services. the amount of money that people pay when they buy a good or service ; the amount they receive when they sell a good or service. the weighted average of the


of borrowed money. the quantity and quality of human effort available to produce goods and services. the amount of money that people pay when they buy a good or service ; the amount they receive when they sell a good or service. the weighted average of the prices of all goods and services in an economy ; used to calculate inflation. people and firms that use resources to make goods and services. a good or service that can be used to satisfy a want. a process of manufacturing, growing, designing, or otherwise using productive resources to create goods or services used to to satisfy a want. goods, often supplied by the government, for which use by one person does not reduce the quantity of the good available for others to use, and for which consumption cannot be limited to those who pay for the good. the amount of goods and services that a monetary unit of income can buy. a decline in the rate of national economic activity, usually measured by a decline in real gdp for at least two consecutive quarters ( i. e., six months ). money set aside for a future use that is held in easily - accessed accounts, such as savings accounts and certificates of deposit ( cds ). activities performed by people, firms or government agencies to satisfy economic wants. use money now to buy goods and services. standard of living the level of subsistence of a nation, social class or individual with reference to the adequacy of necessities and comforts of daily life. compulsory payments to governments by households and businesses. an abstract measure of the satisfaction consumers derive from consuming goods and services. payments for labor services that are directly tied to time worked, or to the number of units of output produced. people employed to do work, producing goods and services.


twenty ideas for engaging projectsseptember 12, 2011 | suzie boss the start of the school year offers an ideal time to introduce students to project - based learning. by starting with engaging projects, you ' ll grab their interest while establishing a solid foundation of important skills, such as knowing how to conduct research, engage experts, and collaborate with peers. in honor of edutopia ' s 20th anniversary, here are 20 project ideas to get learning off to a good start. 1. flat stanley refresh : flat stanley literacy projects are perennial favorites for inspiring students to communicate and connect, often across great distances. now flat stanley has his own apps for iphone and ipad, along with new online resources. project founder dale hubert is recently retired from the classroom, but he ' s still generating fresh ideas to bring learning alive in the " flatlands. " 2. pbl is no accident : in west virginia, project - based learning has been adopted as a statewide strategy for improving teaching and learning. teachers don ' t have to look far to find good project ideas. in this cnn story about the state ' s educational approach, read about a project that grew out of a fender - bender in a school parking lot. when students were asked to come up with a better design for the lot, they applied their understanding of geometry, civics, law, engineering, and public speaking. find more good ideas in west virginia ' s teach21 project library. 3. defy gravity : give your students a chance to investigate what happens near zero gravity by challenging them to design an experiment for nasa to conduct at its 2. 2 second drop tower in brookpark, ohio. separate nasa programs are offered for middle school and high school. or, propose a project that may land you a seat on the ultimate roller coaster ( aka : the " vomit comet " ), nasa aircraft that produces periods of micro and hyper gravity ranging from 0 to 2 g ' s. proposal deadline is sept. 21, and flight week takes place in february 2012. 4. connect across disciplines : when students design and build kinetic sculptures, they expand their understanding of art, history, engineering, language arts, and technology. get some interdisciplinary project insights from the edutopia video, kinetic conundrum. click on the accompanying links for more tips about how you can do it, too. 5. honor home languages : english language learners can feel pressured to master english fast, with class time spent correcting errors instead of using language in meaningful ways. digital is, a site published by


when service - learning principles are built into pbl. find more ideas for service - learning projects from the national youth leadership council. 11. locate experts : when students are learning through authentic projects, they often need to connect with experts from the world outside the classroom. find the knowledgeable experts you need for stem projects through the national lab network. it ' s an online network where k - 12 educators can locate experts from the fields of science, technology, engineering and mathematics. 12. build empathy : projects that help students see the world from another person ' s perspective build empathy along with academic outcomes. the edutopia video, " give me shelter ", shows what compassionate learning looks like in action. click on the companion links for more suggestions about how you can do it, too. 13. investigate climate science : take students on an investigation of climate science by joining the newest collaborative project hosted by globe, global learning and observations to benefit the environment. the student climate research campaign includes three components : introductory activities to build a foundation of understanding, intensive observing periods when students around the world gather and report data, and research investigations that students design and conduct. climate project kicks off sept. 12. 14. problem - solvers unite : math fairs take mathematics out of the classroom and into the community, where everyone gets a chance to try their hand at problem solving. galileo educational network explains how to host a math fair. in a nutshell, students set up displays of their math problems but not the solutions. then they entice their parents and invited guests to work on solutions. make the event even more engaging by inviting mathematicians to respond to students ' problems. 15. harvest pennies : can small things really add up to big results? it seems so, based on results of the penny harvest. since the project started in new york in 1991, young philanthropists nationwide have raised and donated more than $ 8 million to charitable causes, all through penny drives. the project website explains how to organize students in philanthropy roundtables to study community issues and decide which causes they want to support. 16. gather stories : instead of teaching history from textbooks, put students in the role of historian and help them make sense of the past. learn more about how to plan oral history projects in the edutopia story, " living legends. " teach students about the value of listening by having them gather stories for storycorps. 17. angry bird physics : here ' s a driving question to kickstart a science project : " what are the laws of physics


, " living legends. " teach students about the value of listening by having them gather stories for storycorps. 17. angry bird physics : here ' s a driving question to kickstart a science project : " what are the laws of physics in angry birds world? " read how physics teachers like frank noschese and john burk are using the web version of the popular mobile game in their classrooms. 18. place - based projects : make local heritage, landscapes, and culture the jumping - off point for compelling projects. that ' s the idea behind place - based education, which encourages students to look closely at their communities. often, they wind up making significant contributions to their communities, as seen in the city of stories project. 19. news they can use : students don ' t have to wait until they ' re grown - ups to start publishing. student newspapers, radio stations, and other journalism projects give them real - life experiences now. award - winning journalism teacher esther wojcicki outlines the benefits this post on the new york times learning network. get more ideas about digital - age citizen journalism projects at mediashift idea lab. 20. the heroes they know : to get acquainted with students at the start of the year and also introduce students to pbl processes, high tech high teacher diana sanchez asked students to create a visual and textual representation of a hero in their own life. their black - and - white exhibits were a source of pride to students, as sanchez explains in her project reflection. get more ideas from the project gallery at high tech high, a network of 11 schools in san diego county that emphasize pbl. to learn more, watch this edutopia video interview with high tech high founding principal larry rosenstock. please tell us about the projects you are planning for this school year. questions about pbl? draw on the wisdom of your colleagues by starting discussions or asking for help in the pbl community.


moderate - intensity aerobic activity aerobic fitness means increasing how well the body uses oxygen, which depends on the condition of the heart, lungs, and muscles. experts tend to describe aerobic activity in three ways : light, moderate, and vigorous. when people do moderate - intensity activities, they notice a faster heartbeat. to get the benefits of moderate activity, a person can : the goal of aerobic fitness is to increase the amount of oxygen that goes to the heart and muscles, which allows them to work longer. any activities, including many kinds of daily activities, that raise the heart rate and keep it up for an extended period of time can improve aerobic fitness. if the activities are done regularly and long enough, they can help improve fitness. experts recommend that adults try to do moderate activity for at least 2½ hours a week. or they can do vigorous activity for at least 1¼ hours a week. people can choose to do one or both types of activity. and it ' s fine to be active in blocks of 10 minutes or more throughout the day and week. teens and children ( starting at age 6 ) should do moderate to vigorous activity at least 1 hour every day. moderate activity is safe for most people, but it ' s always a good idea to talk to your doctor before starting an exercise program. emedicinehealth medical reference from healthwise to learn more visit healthwise. org find out what women really need. pill identifier on rxlist - quick, easy, find a local pharmacy - including 24 hour, pharmacies


the energy [ r ] evolution the climate change imperative demands nothing short of an energy [ r ] evolution. the expert consensus is that this fundamental shift must begin immediately and be well underway within the next ten years in order to avert the worst impacts. what is needed is a complete transformation of the way we produce, consume and distribute energy, while at the same time maintaining economic growth. nothing short of such a revolution will enable us to limit global warming to less than a rise in temperature of 2° celsius, above which the impacts become devastating. current electricity generation relies mainly on burning fossil fuels, with their associated co2 emissions, in very large power stations which waste much of their primary input energy. more energy is lost as the power is moved around the electricity grid network and converted from high transmission voltage down to a supply suitable for domestic or commercial consumers. the system is innately vulnerable to disruption : localised technical, weather - related or even deliberately caused faults can quickly cascade, resulting in widespread blackouts. whichever technology is used to generate electricity within this old fashioned configuration, it will inevitably be subject to some, or all, of these problems. at the core of the energy [ r ] evolution there therefore needs to be a change in the way that energy is both produced and distributed. 4. 1 key principles the energy [ r ] evolution can be achieved by adhering to five key principles : 1. respect natural limits – phase out fossil fuels by the end of this century we must learn to respect natural limits. there is only so much carbon that the atmosphere can absorb. each year humans emit over 25 billion tonnes of carbon equivalent ; we are literally filling up the sky. geological resources of coal could provide several hundred years of fuel, but we cannot burn them and keep within safe limits. oil and coal development must be ended. the global energy [ r ] evolution scenario has a target to reduce energy related co2 emissions to a maximum of 10 gigatonnes ( gt ) by 2050 and phase out fossil fuels by 2085. 2. equity and fairness as long as there are natural limits there needs to be a fair distribution of benefits and costs within societies, between nations and between present and future generations. at one extreme, a third of the world ’ s population has no access to electricity, whilst the most industrialised countries consume much more than their fair share. the effects of climate change on the poorest communities are exacerbated by massive global energy inequality. if we are to address climate change, one of the core principles


electricity, whilst the most industrialised countries consume much more than their fair share. the effects of climate change on the poorest communities are exacerbated by massive global energy inequality. if we are to address climate change, one of the core principles must be equity and fairness, so that the benefits of energy services – such as light, heat, power and transport – are available for all : north and south, rich and poor. only in this way can we create true energy security, as well as the conditions for genuine human wellbeing. the advanced energy [ r ] evolution scenario has a target to achieve energy equity as soon as technically possible. by 2050 the average per capita emission should be between 1 and 2 tonnes of co2. 3. implement clean, renewable solutions and decentralise energy systems. there is no energy shortage. all we need to do is use existing technologies to harness energy effectively and efficiently. renewable energy and energy efficiency measures are ready, viable and increasingly competitive. wind, solar and other renewable energy technologies have experienced double digit market growth for the past decade. just as climate change is real, so is the renewable energy sector. sustainable decentralised energy systems produce less carbon emissions, are cheaper and involve less dependence on imported fuel. they create more jobs and empower local communities. decentralised systems are more secure and more efficient. this is what the energy [ r ] evolution must aim to create. to stop the earth ’ s climate spinning out of control, most of the world ’ s fossil fuel reserves – coal, oil and gas – must remain in the ground. our goal is for humans to live within the natural limits of our small planet. 4. decouple growth from fossil fuel use starting in the developed countries, economic growth must be fully decoupled from fossil fuel usage. it is a fallacy to suggest that economic growth must be predicated on their increased combustion. we need to use the energy we produce much more efficiently, and we need to make the transition to renewable energy and away from fossil fuels quickly in order to enable clean and sustainable growth. 5. phase out dirty, unsustainable energywe need to phase out coal and nuclear power. we cannot continue to build coal plants at a time when emissions pose a real and present danger to both ecosystems and people. and we cannot continue to fuel the myriad nuclear threats by pretending nuclear power can in any way help to combat climate change. there is no role for nuclear power in the energy [ r ] evolution.


hold the salt : ucla engineers develop revolutionary new desalination membrane process uses atmospheric pressure plasma to create filtering ' brush layer ' desalination can become more economical and used as a viable alternate water resource. by wileen wong kromhout originally published in ucla newsroom researchers from the ucla henry samueli school of engineering and applied science have unveiled a new class of reverse - osmosis membranes for desalination that resist the clogging which typically occurs when seawater, brackish water and waste water are purified. the highly permeable, surface - structured membrane can easily be incorporated into today ' s commercial production system, the researchers say, and could help to significantly reduce desalination operating costs. their findings appear in the current issue of the journal of materials chemistry. reverse - osmosis ( ro ) desalination uses high pressure to force polluted water through the pores of a membrane. while water molecules pass through the pores, mineral salt ions, bacteria and other impurities cannot. over time, these particles build up on the membrane ' s surface, leading to clogging and membrane damage. this scaling and fouling places higher energy demands on the pumping system and necessitates costly cleanup and membrane replacement. the new ucla membrane ' s novel surface topography and chemistry allow it to avoid such drawbacks. " besides possessing high water permeability, the new membrane also shows high rejection characteristics and long - term stability, " said nancy h. lin, a ucla engineering senior researcher and the study ' s lead author. " structuring the membrane surface does not require a long reaction time, high reaction temperature or the use of a vacuum chamber. the anti - scaling property, which can increase membrane life and decrease operational costs, is superior to existing commercial membranes. " the new membrane was synthesized through a three - step process. first, researchers synthesized a polyamide thin - film composite membrane using conventional interfacial polymerization. next, they activated the polyamide surface with atmospheric pressure plasma to create active sites on the surface. finally, these active sites were used to initiate a graft polymerization reaction with a monomer solution to create a polymer " brush layer " on the polyamide surface. this graft polymerization is carried out for a specific period of time at a specific temperature in order to control the brush layer thickness and topography. " in the early years, surface plasma treatment could only be accomplished in a vacuum chamber, " said yoram cohen, ucla professor of chemical


out for a specific period of time at a specific temperature in order to control the brush layer thickness and topography. " in the early years, surface plasma treatment could only be accomplished in a vacuum chamber, " said yoram cohen, ucla professor of chemical and biomolecular engineering and a corresponding author of the study. " it wasn ' t practical for large - scale commercialization because thousands of meters of membranes could not be synthesized in a vacuum chamber. it ' s too costly. but now, with the advent of atmospheric pressure plasma, we don ' t even need to initiate the reaction chemically. it ' s as simple as brushing the surface with plasma, and it can be done for almost any surface. " in this new membrane, the polymer chains of the tethered brush layer are in constant motion. the chains are chemically anchored to the surface and are thus more thermally stable, relative to physically coated polymer films. water flow also adds to the brush layer ' s movement, making it extremely difficult for bacteria and other colloidal matter to anchor to the surface of the membrane. " if you ' ve ever snorkeled, you ' ll know that sea kelp move back and forth with the current or water flow, " cohen said. " so imagine that you have this varied structure with continuous movement. protein or bacteria need to be able to anchor to multiple spots on the membrane to attach themselves to the surface — a task which is extremely difficult to attain due to the constant motion of the brush layer. the polymer chains protect and screen the membrane surface underneath. " another factor in preventing adhesion is the surface charge of the membrane. cohen ' s team is able to choose the chemistry of the brush layer to impart the desired surface charge, enabling the membrane to repel molecules of an opposite charge. the team ' s next step is to expand the membrane synthesis into a much larger, continuous process and to optimize the new membrane ' s performance for different water sources. " we want to be able to narrow down and create a membrane selection system for different water sources that have different fouling tendencies, " lin said. " with such knowledge, one can optimize the membrane surface properties with different polymer brush layers to delay or prevent the onset of membrane fouling and scaling. " the cost of desalination will therefore decrease when we reduce the cost of chemicals [ used for membrane cleaning ], as well as process operation [ for membrane replacement ]. desalination can become more economical and used as a viable


located above the surface of our planet is a complex mixture of gases and suspended liquid and solid particles known as the atmosphere. operating within the atmosphere is a variety of processes we call weather. some measurable variables associated with weather include air temperature, air pressure, humidity, wind, and precipitation. the atmosphere also contains organized phenomena that include things like tornadoes, thunderstorms, mid - latitude cyclones, hurricanes, and monsoons. climate refers to the general pattern of weather for a region over specific period of time. scientists have discovered that human activities can influence earth ’ s climate and weather producing problems like global warming, ozone depletion, and acid precipitation. widespread urban development alters weather patterns research focusing on the houston area suggests that widespread urban development alters weather patterns in a way that... laptev sealast updated on 2013 - 05 - 14 at 14 : 23 the laptev sea is a saline water body, lodged between the kara sea and east siberian sea. the chief land boundary of this marginal sea of the arctic ocean is the siberian... more » east siberian sealast updated on 2013 - 05 - 14 at 14 : 09 the east siberian sea is a saline marine body, which is a southern marginal sea of the arctic ocean. to the east is found the chukchi sea and to the west beyond the new... more » baffin baylast updated on 2013 - 05 - 14 at 12 : 11 baffin bay is a margibnal sea of the north atlantic ocean located between the canada ' s baffin, devon and ellesmere islands and greenland. to the south the davis strait... more » andaman sealast updated on 2013 - 05 - 13 at 23 : 06 the andaman sea is a body of marine water in the northeastern corner of the indian ocean that lies to the west of the malay peninsula, the north of sumatra, the east of the... more » molucca sealast updated on 2013 - 05 - 13 at 23 : 02 the molucca sea ( also molukka sea ) is a semi - enclosed sea, surrounded by a variety of islands belonging to indonesia, most significantly the island of sulawesi ( celebes )... more » levantine sealast updated on 2013 - 05 - 13 at 22 : 31 the levantine sea is most eastern unit of the mediterranean sea, and also the most saline portion of the mediterranean basin. the levantine sea, also known as the levant... more »


university of michigan ( u - m ) scientists have made an important step toward what could become the first vaccine in the u. s. to prevent urinary tract infections, if the robust immunity achieved in mice can be reproduced in humans. the findings are published september 18 in the open - access journal plos pathogens. urinary tract infections ( utis ) affect 53 percent of women and 14 percent of men at least once in their lives. these infections lead to lost work time and 6. 8 million medical provider ' s office visits, 1. 3 million emergency room visits and 245, 000 hospitalizations a year, with an annual cost of $ 2. 4 billion in the united states. to help combat this common health issue, the u - m scientists used a novel systematic approach, combining bioinformatics, genomics and proteomics, to look for key parts of the bacterium, escherichia coli, that could be used in a vaccine to elicit an effective immune response. the team, led by dr. harry l. t. mobley, ph. d., screened 5, 379 possible bacterial proteins and identified three strong candidates to use in a vaccine to prime the body to fight e. coli, the cause of most uncomplicated urinary tract infections. the vaccine prevented infection and produced key types of immunity when tested in mice. scientists have attempted to develop a vaccine for utis over the past two decades. this latest potential vaccine has features that may better its chances of success. it alerts the immune system to iron receptors on the surface of bacteria that perform a critical function allowing infection to spread. administered in the nose, it induces an immune response in the body ' s mucosa, a first line of defense against invading pathogens. the response, also produced in mucosal tissue in the urinary tract, should help the body fight infection where it starts. mobley ' s team is currently testing more strains of e. coli obtained from women treated at u - m. most of the strains produce the same iron - related proteins that cthe vaccine targets, an encouraging sign that the vaccine could work against many urinary tract infections. mobley is seeking partners in clinical research to move the vaccine forward into a phase 1 trial in humans. if successful, this vaccine would take several more years to reach the market. financial disclosure : this work has been funded by public health service grant ai043363 from the national institutes of health. the funders had


phase 1 trial in humans. if successful, this vaccine would take several more years to reach the market. financial disclosure : this work has been funded by public health service grant ai043363 from the national institutes of health. the funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. competing interests : the authors have declared that no competing interests exist. please add this link to the published article in online versions of your report : http : / / dx. plos. org / 10. 1371 / journal. ppat. 1000586 ( link will go live upon embargo lift ) citation : alteri cj, hagan ec, sivick ke, smith sn, mobley hlt ( 2009 ) mucosal immunization with iron receptor antigens protects against urinary tract infection. plos pathog 5 ( 9 ) : e1000586. doi : 10. 1371 / journal. ppat. 1000586 anne rueter, firstname. lastname @ example. org nicole fawcett, email @ example. com this press release refers to an upcoming article in plos pathogens. the release is provided by the article authors and their institution. any opinions expressed in these releases or articles are the personal views of the journal staff and / or article contributors, and do not necessarily represent the views or policies of plos. plos expressly disclaims any and all warranties and liability in connection with the information found in the releases and articles and your use of such information. about plos pathogens plos pathogens ( www. plospathogens. org ) publishes outstanding original articles that significantly advance the understanding of pathogens and how they interact with their host organisms. all works published in plos pathogens are open access. everything is immediately available subject only to the condition that the original authorship and source are properly attributed. copyright is retained by the authors. the public library of science uses the creative commons attribution license. about the public library of science the public library of science ( plos ) is a non - profit organization of scientists and physicians committed to making the world ' s scientific and medical literature a freely available public resource. for more information, visit http : / / www. plos. org. aaas and eurekalert! are not responsible for the accuracy of news releases posted to eurekalert! by contributing institutions or for the use of any information through the


let ’ s start with the understanding that the federal trade commission states that if scrap generated in the manufacturing process is reused for manufacturing new product, it can not be calculated as post - industrial recycled content, as this reuse of scrap is a part of the typical manufacturing process. so your first question when receiving post - industrial recycled content data should be, “ how did you make this calculation, and where did the recycled waste come from? ” stakeholder demand for recycled content in building products has been largely driven by the leed® rating system, and the points gained by contributing to the recycled content credit. now, since scrap reused in the manufacturing process can not be calculated, many manufactures play a form of the “ shell game ”. if a manufacturer has multiple facilities making products that generate scrap which can be reused in all the manufacturing processes then, to calculate post - industrial recycled content, the scrap is just moved between facilities. now the scrap is claimed to be diverted from landfill and calculated as recycled content. please understand that for a recycling program to work, a manufacturer needs a continuous feedstock of waste material, so some of this moving around of scrap is legitimate. if the manufacturer is playing the shell game just “ for the points, ” then all that is being done is increased energy use and co2 emissions... how sustainable is that?


notion of virginity in the early church. " christian spirituality : origins to the 12th c. editor : bernard mcginn and john meyendorff. new york : crossroad ( 1985 ) : 427 - 43. grundler, otto. " devotio moderna. " christian spirituality : high middle ages and reformation. editor : jill raitt. new york : crossroad ( 1987 ) : 176 - 93. knowles, david. christian monasticism. new york : mcgraw - hill, 1969. leclercq, jean. monks and love in 12th - c. france. oxford : clarendon, 1979. novak, michael. " the free churches and the roman church. " journal of ecumenical studies, 2 ( 1965 ) : 426 - 47. rousseau, phillip. ascetics, authority, and the church in the age of jerome and cassian. new york ; oxford, 1980. workman, herbert b. the evolution of the monastic ideal from the earliest times to the coming of the friars. 2nd edition. london, 1927, reprinted with introduction by david knowles. boston : beacon, 1962. adapted by permission of herald press, harrisonburg, virginia, and waterloo, ontario, from mennonite encyclopedia, vol. 5, pp. 601 - 602. all rights reserved. for information on ordering the encyclopedia visit the herald press website. ©1996 - 2013 by the global anabaptist mennonite encyclopedia online. all rights reserved. mla style : martin, dennis d. " monasticism. " global anabaptist mennonite encyclopedia online. 1987. web. 18 may 2013. http : / / www. gameo. org / encyclopedia / contents / m653. html. apa style : martin, dennis d. ( 1987 ). monasticism. global anabaptist mennonite encyclopedia online. retrieved 18 may 2013, from http : / / www. gameo. org / encyclopedia / contents / m653. html.


a genome - wide association study appearing in plos genetics that involved thousands of individuals of european ancestry identified five genetic loci that appear to be associated with facial features. among them : variants in and around genes implicated in prior studies of conditions that are characterized by face and / or skull malformations. the researchers behind the study, members of the international visible trait genetics, or visigen, consortium, argue that the new findings could contribute to what ' s known about facial evolution and development in humans, while at once laying the foundation for forensic tools for predicting facial features based on dna alone. for more on this study, see this story from our sister publication genomeweb daily news. investigators from the cleveland clinic and elsewhere used post - mortem brain samples to look at the epigenetic and transcriptional profiles associated with autism spectrum disorder. as they reported in plos one, the researchers relied on arrays and bisulfite sequencing to assess genome - wide gene expression and dna methylation profiles in two brain regions — the cerebellar hemisphere cortex and the brodmann area 19 occipital cortex — in samples from nine males with idiopathic cases of autism spectrum disorder and nine unaffected male controls in the same age range. overall brain expression patterns varied from one individual with asd to the next. but the team did uncover some shared features within the asd samples, including lower - than - usual expression of genes in mitochondrial oxidative phosphorylation and protein production pathways in the brain samples from individuals with autism and shifts in the expression of certain brain - related genes. a plos pathogens study of dengue virus by french researchers explores the basis for the pronounced conservation that ' s been noted in nucleotides found at the ends of the virus ' rna - based genome. using chemical synthesis experiments, assays, and other analyses, the group determined that the virus, a representative of the flavivirus genus, relies on an rna end - repair process that involves the rna - dependent rna polymerase produced by a dengue virus gene called ns5. " our findings provide a direct demonstration of the implication of a viral rna polymerase in the conservation and repair of genome ends, " the study ' s authors wrote. " other polymerases from other rna virus families are likely to employ similar mechanisms. "


us 4884575 a a cardiac pacemaker pulse generator is adapted to. generate electrical stimuli at a first pacing rate, and to selectively increase the rate to a second higher pacing rate. a timer triggers the rate increase to establish the higher rate as an exercise rate folloing the passage of a preset period of time after the timer is enabled. an external magnet controlled by the patient activates a reed switch to enable the timer to commence timing. the pulse generator is further adapted to respond to a second pass of the magnet over the reed switch after enabling of the timer to thereupon disable the timer before the preset period of time has expired. if the second pass of the magnet occurs after the exercise rate has begun, the element for increasing the rate is disabled to return the pulse generator to the lower pacing rate. the change in pacing rates is made in steps. 1. in combination with an implantable cardiac pacemaker for delivering electrical stimuli to the heart of a patient to pace the heart rate, said pacemaker comprising : pulse generator means for selectively producing said electrical stimuli at a fixed resting rate and at a higher exercise rate, lead means associated with said pulse generator for delivering said stimuli to a selected chamber of the heart, and timer means for stepping - up said pulse generator means from said resting rate to said exercise rate after an adjustable preset delay following activation of said timer means, said preset delay being of a duration perceptible by the patient ; and external control means for patient initiation of a first command to said pacemaker to activate said timer means. 2. in combination with an implantable cardiac pacemaker for delivering electrical stimuli to the heart of a patient to pace the heart rate, said pacemaker comprising : pulse generator means for selectively producing said electrical stimuli at a fixed resting rate and a higher exercise rate, lead means associated with said pulse generator for delivering said stimuli to a selected chamber of the heart, and delay means for stepping - up said pulse generator means from said resting rate to said exercise rate after an adjustable preset delay following activation of said delay means, means associated with said pulse generator means and said delay means for maintaining said exercise rate for a predetermined time interval following said preset delay and then returning said pulse generator means to said resting rate ; and an external control means for patient - initiation of a command to said pacemaker to activate said delay means. 3. the combination according to claim 2, wherein said delay means is responsive to a second command initiated by the patient from


said resting rate ; and an external control means for patient - initiation of a command to said pacemaker to activate said delay means. 3. the combination according to claim 2, wherein said delay means is responsive to a second command initiated by the patient from said external control means at any time after receipt of the first said command and before the expiration of said predetermined time interval, to cancel the activation of said delay means. 4. the combination according to claim 3, wherein the stepping up and returning of said rates at which said stimuli are produced by said pulse generator means is effected gradually. 5. an implantable pulse generator unit for a cardiac pacemaker for use with an external magnet to permit patient - initiated adjustment of pacing rate from a resting rate to an exercise rate and vice versa, said unit comprising : generator means for generating electrical stimuli at said resting rate, control means associated with said generator means responsive, when enabled, for controllably increasing the rate at which electrical stimuli are generated from said generator means from said resting rate to said exercise rate, and timer means responsive to positioning of said external magnet in proximity to said pulse generator unit for enabling said control means an adjustable preset delay period after said positioning, said preset delay period being of a duration perceptible to the patient. 6. an implantable pulse generator unit for a cardiac pacemaker for use with an external magnet to permit patient - initiated adjustment of pacing rate from a resting rate to an exercise rate and vice versa, said unit comprising : generator means for generating electrical stimuli at said resting rate, control means associated with said generator means responsive, when enabled, for controllably increasing the rate at which electrical stimuli are generated by said generator means from said resting rate to said exercise rate, said control means including timing means for maintaining the rate at which electrical stimuli are generated by said generator means at said exercise rate for a predetermined time interval ; and delay means responsive to positioning of said external magnet in proximity to said pulse generator unit for enabling said control means an adjustable preset delay period thereafter. 7. the pulse generator unit of claim 6, wherein said control means automatically returns said generator means to said resting rate following the expiration of said predetermined time interval. 8. the pulse generator unit of claim 7, wherein said control means gradually increases the rate at which electrical stimuli are generated by said generator means from said resting rate to said exercise rate, and gradually returns said generator means to said resting rate following the expiration of said predetermined


claim 7, wherein said control means gradually increases the rate at which electrical stimuli are generated by said generator means from said resting rate to said exercise rate, and gradually returns said generator means to said resting rate following the expiration of said predetermined time interval. 9. the pulse generator unit of claim 6, wherein said delay means is responsive to a repositioning of said external magnet in proximity to said pulse generator unit after said control means has been enabled, for disabling said control means. 10. a cardiac pacemaker pulse generator for generating electrical stimuli to be delivered to the heart of a patient to pace the heart rate, said generator comprising : means for generating said electrical stimuli at a first pacing rate, means electrically connected to said stimuli generating means for selectively increasing the rate at which said stimuli are generated to a second higher pacing rate, timing means for triggering said rate increasing means to increase said first pacing rate to a second higher pacing rate upon passage of an adjustable preselected period of time after said timing means is enabled, said preselected period of time being of a duration perceptible by the patient, means responsive to a command signal from a patient - activated external device for enabling said timing means to commence timing. 11. the pulse generator according to claim 10, wherein said enabling means is further responsive to a second command signal after said timing means is enabled, to disable said timing means prior to passage of said preselected period of time. 12. the pulse generator according to claim 10, further including means responsive to a second command signal while said stimuli are being generated at said second higher pacing rate, for disabling said rate increasing means and thereby returning the rate at which said stimuli are generated by said stimuli generating means to said first pacing rate. 13. the pulse generator according to claim 12, wherein said rate increasing means is responsive, when disabled, to decrementally reduce the rate at which said stimuli are generated by said stimuli generating means. 14. the pulse generator according to claim 10, wherein said rate increasing means is responsive to said timing means reaching preset time intervals toward passage of said preselected period of time, for incrementally increasing the rate at which said stimuli are generated by said stimuli generating means in steps as each preset time interval is reached. 15. the method of pacing a pacemaker patient ' s heart rate using a magnet - controlled implantable pulse generator to adjust the stimulation rate from a resting rate to an exercise rate and vice versa, comprising


as each preset time interval is reached. 15. the method of pacing a pacemaker patient ' s heart rate using a magnet - controlled implantable pulse generator to adjust the stimulation rate from a resting rate to an exercise rate and vice versa, comprising the steps of maintaining the stimulation rate of said pulse generator at said resting rate, initiating a command signal to reset the stimulation rate of said pulse generator to said exercise rate after an adjustable programmed delay period following said command signal, and returning the stimulation rate of said pulse generator to said resting rate in increments following a predetermined interval of time at said exercise rate. the present invention relates generally to medical devices, and more particularly to implantable artificial cardiac pacemakers adapted to provide patient - variable stimulation rates appropriate to a condition of exercise by the patient. the resting heart rate of sinus rhythm, that is, the rate determined by the spontaneously rhythmic electrophysiologic property of the heart ' s natural pacemaker, the sinus node, is typically in the range from about 65 to about 85 beats per minute ( bpm ) for adults. disruption of the natural cardiac pacing and propagation system may occur with advanced age and / or cardiac disease, and is often treated by implanting an artificial cardiac pacemaker in the patient to restore and maintain the resting heart rate to the proper range. in its simplest form, an implantable pacemaker for treatment of bradycardia ( abnormally low resting rate, typically below 60 beats per minute ( bpm ) ) includes an electrical pulse generator powered by a self - contained battery pack, and a catheter lead including at the distal end a stimulating cathodic electrode electrically coupled to the pulse generator. the lead is implanted intravenously to position the cathodic electrode in stimulating relation to excitable myocardial tissue in the selected chamber on the right side of the patient ' s heart. the pulse generator unit is surgically implanted in a subcutaneous pouch in the patient ' s chest, and has an integral electrical connector to receive a mating connector at the proximal end of the lead. in operation of the pacemaker, the electrical pulses are delivered ( typically, on demand ) via the lead / electrode system, including an anodic electrode such as a ring behind the tip for bipolar stimulation or a portion of the pulse generator case for unipolar stimulation, and the body tissue and fluid, to stimulate the excitable myocardial tissue. pacemakers may operate in different response modes, such as asynch


tip for bipolar stimulation or a portion of the pulse generator case for unipolar stimulation, and the body tissue and fluid, to stimulate the excitable myocardial tissue. pacemakers may operate in different response modes, such as asynchronous ( fixed rate ), inhibited ( stimulus generated in absence of specified cardiac activity ), or triggered ( stimulus delivered in presence of specified cardiac activity ). further, present - day pacers range from the simple fixed rate device that offers pacing with no sensing ( of cardiac activity ) function, to fully automatic dual chamber pacing and sensing functions ( so - called ddd pacemakers ) which may provide a degree of physiologic pacing by at least a slight adjustment of heart rate according to varying metabolic conditions in a manner akin to the natural pacing of the heart. thus, some ddd pacemaker patients experience an increased pacing rate with physical exertion, with concomitantly higher cardiac output, and thereby, an ability to handle low levels of exercise. unfortunately, a significant percentage of the pacemaker patient population, who suffer from atrial flutter, atrial fibrillation or sick - sinus syndrome, for example, cannot obtain the benefit of exercise - responsive pacing with conventional atrial - triggered pacemakers. moreover, the ddd - type pacemakers are complex and costly to manufacture, which is reflected in a higher price to the patient. it is a principal object of the present invention to provide a relatively simple and inexpensive pacemaker which provides pacing at a desired resting rate, and which is subject to limited control by the patient to provide a desired exercise rate for a preset period of time following which the pacemaker returns to the resting rate. various types of rate responsive pacemakers have been proposed which would sense a physiological parameter that varies as a consequence of physical stress, such as respiration, blood oxygen saturation or blood temperature, or merely detect physical movement, and correspondingly adjust the pacing rate. many of these rate responsive pacemakers may also be relatively complex, and therefore expensive to the patient. the present invention is directed toward a low cost pacemaker which can be adjusted at will by the patient, subject to the limited amount of control programmed into the device by the physician for that patient. according to the invention, patient control is manifested by bringing an external magnet into proximity with an implanted reed switch associated with the pacemaker. of course, limited magnet control has been afforded to the patient in the past for some purposes, such as to enable transtelephon


patient control is manifested by bringing an external magnet into proximity with an implanted reed switch associated with the pacemaker. of course, limited magnet control has been afforded to the patient in the past for some purposes, such as to enable transtelephonic monitoring of the pacemaker functions. also, techniques are presently available which permit external adjustment of the stimulation rate of the pacemaker after implantation, as by means of a programming unit available to the physician. for obvious reasons, it is undesirable to give the patient the same latitude to control his pacemaker. in u. s. pat. no. 3, 623, 486, berkovits disclosed a pacemaker adapted to operate at either of two stimulation rates, and switchable from one to the other by the physician using an external magnet. in this manner, the physician would be able to control the pacer mode and rate according to the needs of the particular patient. the purpose, in part, was to provide a pacemaker which had some adaptability to the patient ' s requirements. however, once set by the physician, the selected resting rate was maintained for that patient by the implanted pacer. another technique for external adjustment of pacing rate by the physician is found in the disclosures of u. s. pat. no. 3, 198. 195 to chardack, and u. s. pat. no. 3, 738, 369 to adams et al. in each, rate control is exercised by inserting a needle through a pacemaker aperture beneath the patient ' s skin to adjust a mechanism. in the adams et al. disclosure, the needle is used to change the position of a magnet within the paper to actuate a rate - controlling reed switch. in u. s. pat. no. 3, 766, 928, goldberg et al. describe an arrangement for continuous adjustment of rate by a physician using an external magnet that cooperates with a magnet attached to the shaft of a rate potentiometer in the implanted pacemaker, to provide the initial setting of pacing rate desirable for the particular patient. more recent proposals offer the patient limited control over the pacing rate. in u. s. pat. no. 4, 365, 633, loughman et al. disclose a pacemaker programmer which is conditioned by the physician to give the patient the capability to select any of three distinct rates : for sleep, for an awake resting state, and for exercise. the programmer generates a pulsating electromagnetic field,


al. disclose a pacemaker programmer which is conditioned by the physician to give the patient the capability to select any of three distinct rates : for sleep, for an awake resting state, and for exercise. the programmer generates a pulsating electromagnetic field, and allows the patient to select any of those three modes with an abrupt change in rate when the coil pod of the programmer is positioned over the implanted pacemaker. it is, of course, necessary to have the programmer at hand in order to change the stimulation rate, and the use of the device in public can be a source of extreme embarassment to the patient. in u. s. pat. no. 4, 545, 380, schroeppel describes a technique for manual adjustment of rate control contrasted with the activity sensing, automatic rate control disclosed by dahl in u. s. pat. no. 4, 140, 132. according to the schroeppel patent, a piezoelectric sensor and associated circuitry are combined with the implanted pulse generator of the pacemaker to allow the patient to change from a resting rate to a higher rate by sharp taps on his chest near the site of the piezoelectric sensor. such an arrangement requires that the sensor be sufficiently sensitive to respond to the patient ' s sharp taps, and yet be insensitive to the everyday occurrences the patient encounters while undergoing normal activities and which could otherwise result in false triggerings. these include presence in the vicinity of loud noise such as is generated by street traffic, being jostled in a crowd, experiencing bumps and vibrations while riding in a vehicle, and the like. further, even when controlled in the manner described, this type of switching results in an abrupt, non - physiological change of rate. accordingly, it is another object of the present invention to provide a pacemaker which is capable of being controlled externally by the patient to assume exercise and non - exercise rate modes, in a manner that allows discreet and yet reliable control. yet another object of the invention is to provide a cardiac pacemaker whose stimulation rate is controllable by and according to a schedule selected by the patient. briefly, according to the present invention a cardiac pacemaker is manually controllable by the patient to preset time intervals of operation at a relatively high ( exercise ) rate and lower ( resting ) rate according to the patient ' s own predetermined schedule of exercise and rest. an important aspect of the invention is that the pulse generator may be implemented to undergo an adjustment of stimulation rate from


high ( exercise ) rate and lower ( resting ) rate according to the patient ' s own predetermined schedule of exercise and rest. an important aspect of the invention is that the pulse generator may be implemented to undergo an adjustment of stimulation rate from a fixed resting rate of, say, 75 bpm, to a preselected exercise rate of, say, 120 bpm, following a predetermined period of time after activation by the patient using an external magnet, that is, after a predetermined delay following a patient - initiated command signal, and to remain at the higher rate for a preselected time interval. thus, the patient may effectively " set a clock " in his pacemaker to elevate his heart rate at the time and for the duration of a scheduled exercise session, such as a game of tennis. moreover, he may activate the pacemaker in this manner in the privacy of his own home well in advance of the exercise session. according to another aspect of the invention, the pulse generator is implemented to return automatically to the resting rate at the expiration of the preselected exercise rate time interval. hence, the patient need not carry his magnet with him to readjust the pacer to the resting rate at the completion of the scheduled exercise session. according to this aspect, after operating at the elevated stimulation rate for a time interval preselected to be suitable for the exercise session, say, one hour, the generator resets itself to return to the initial resting rate. according to another feature of the invention, the rate is incremented and decremented in steps from one rate setting to the other to avoid abrupt changes, and therefore to provide a more physiological rate control than has heretofore been available in manually controlled pacemakers. a further feature of the invention is that the pulse generator may be activated to disable the exercise rate command at any time after it has been given, including that to produce an early conclusion to an already - commenced exercise session. for example, if a scheduled tennis game or bicycling run is called off by the patient ' s partner after the patient has programmed in the higher rate, he need merely apply the magnet in proximity to the implanted pulse generator again to cancel the previous command and maintain the fixed resting rate. similarly, if the exercise session is shortened, the rate may be returned to the resting rate by simply applying the magnet over the pulse generator. the above and still further objects, aspects, features and attendant advantages of


command and maintain the fixed resting rate. similarly, if the exercise session is shortened, the rate may be returned to the resting rate by simply applying the magnet over the pulse generator. the above and still further objects, aspects, features and attendant advantages of the present invention will become apparent to those of ordinary skill in the field to which the invention applies from a consideration of the following detailed description of a preferred embodiment thereof, taken in conjunction with the accompanying drawing, in which : fig. 1 is a block circuit diagram of a pulse generator unit of a cardiac pacemaker according to a preferred embodiment of the invention. referring now to fig. 1, an implantable pulse generator unit 10 includes a pulse generator 12 and batteries 15 housed in a biocompatible metal case 17. pulse generator 12 is implemented to be rate limited to generate output pulses at rates up to either of two low / high limit rates - - for example, 75 pulses per minute ( ppm ) and 120 ppm, respectively - - and to be incremented from the lower rate to the higher rate and decremented from the higher rate to the lower rate under the control of an up / down counter 18 associated with the pulse generator 12 in unit 10. counter 18 may be set by application of a voltage level to its " up " input to commence counting toward the higher rate, and thereby to incrementally step the pulse repetition frequency up to that rate, and may be reset by application of a voltage level to its " down " input to commence counting toward the lower rate, and thereby decrementally step the pulse repetition frequency down to that rate. this is accomplished under the control of set and reset output voltage levels generated by a flip - flop circuit 21 also housed in case 17. the pulse generator unit 10 also includes a reed switch 25 which is actuable by placement of a magnet 27, external to the skin of the patient in whom the unit 10 is implanted, in proximity to case 17. reed switch 25, when actuated, serves to enable a delay timer 29 in unit 10. the delay timer responds to the enabling input to commence timing of its preset time delay interval. at the end of the delay interval, delay timer 29 produces a pulse for application to the flip - flop 21. subsequent actuation of the reed switch before the timer 29 has timed out serves to disable the timer and reset it in preparation for a subsequent enabling signal from the reed switch. if timer 29 has already timed out before the reed switch is


flop 21. subsequent actuation of the reed switch before the timer 29 has timed out serves to disable the timer and reset it in preparation for a subsequent enabling signal from the reed switch. if timer 29 has already timed out before the reed switch is again actuated, the timer will respond to the disabling input, when the reed switch is actuated, to produce another pulse for application to the flip - flop 21. the flip - flop is thereupon reset and produces its reset output voltage level. the set and reset output voltage levels of flip - flop 21 are also applied respectively to " set " and " reset " inputs of an interval timer 30. upon being set, the interval timer commences timing out a predetermined time interval, and, at the expiration of that interval, generates a pulse for application to flip - flop 21. upon being reset, the interval timer 30 is returned to the start of the predetermined time interval in preparation for initiating the timing of that interval on receipt at its " set " input of the next set output voltage level from the flip - flop. the preset time period of delay timer 29 and the predetermined time interval of interval timer 30 are programmable by the physician according to the desires and needs of the particular patient. if, for example, the patient has a regularly scheduled early morning brisk walking session of one hour with friends, and resides near the starting point of the walk, the time period of the delay timer 29 may be programmed to be fifteen minutes. the time interval of the interval timer 30 is programmed to be one hour in length. in operation, the pulse generator produces output pulses at the resting rate prescribed ( and programmed ) by the physician for the particular patient - - in this exemplary embodiment, a resting rate of 75 bpm. the pulses are delivered to the stimulating cathodic electrode 35 in the right ventricle of the heart 40 via a lead 42, the reference electrode ( anode ) and the body tissue and fluids, according to the mode in which the pacemaker is designed to operate. in the preferred embodiment, the pacemaker continues to operate at that rate unless and until the patient elects to initiate the exercise rate cycle. to do so, the patient places the magnet 27 in proximity to the implanted pulse generator unit 10 at about fifteen minutes prior to the appointed time for the exercise session, as a command to actuate reed switch 25. the patient may then choose to leave the magnet at home or take it


magnet 27 in proximity to the implanted pulse generator unit 10 at about fifteen minutes prior to the appointed time for the exercise session, as a command to actuate reed switch 25. the patient may then choose to leave the magnet at home or take it along in the glove compartment of his car, since actuation of the reed switch has enabled the delay timer 29 and nothing more need be done by the patient to enable the pacemaker to commence the exercise rate at the expiration of the preset delay period. before the end of that period the patient has arrived at the starting point for the exercise session, and at the end of the delay period, the delay timer applies a pulse to flip - flop 21 which responds by generating a set output voltage level. the set voltage is applied to both the " up " input of counter 18 and the " set " input of interval timer 30. accordingly, the counter commences its count, preferably at a relatively slow rate of, say, ten counts per minute, and correspondingly incrementally steps the pulse generator 12 output rate up to the upper rate limit of 120 ppm, and thereby gradually increases the patient ' s heart rate from 75 bpm to 120 bpm as the patient commences to exercise. hence, the patient ' s heart rate and cardiac output are now at levels adequate for the patient to carry out the exercise session. the pulse generator continues to supply pulses at the upper rate limit until interval timer 30, which commenced its predetermined time interval with the application of the set input voltage, times out, whereupon the interval timer produces an output pulse which is applied to flip - flop 21 to reset the latter. the flip - flop responds by providing a reset output voltage level for application to the " down " input of counter 18 and the " reset " input of the interval timer. accordingly, the counter decrementally steps the pulse repetition frequency of the pulse generator down, preferably at the ten pulses per minute rate, to the lower rate limit of 75 ppm corresponding to a heart rate of 75 bpm. in this manner, the patient ' s heart rate is reduced gradually from the exercise rate to the resting rate at a time commensurate with the end of the exercise session. also, the resetting of the interval timer by the set output voltage level of the flip - flop assures that the timer is ready to commence timing its predetermined interval on receipt of the next " set " input. in the event that the exercise session is called off


the interval timer by the set output voltage level of the flip - flop assures that the timer is ready to commence timing its predetermined interval on receipt of the next " set " input. in the event that the exercise session is called off at any time after the delay timer 29 has been enabled and before the interval timer has timed out, the patient need merely place the magnet 27 once again in proximity to the implanted pulse generator unit. if the delay timer has not yet timed out, it is disabled by the actuation of the reed switch, and hence, flip - flop 21 remains reset, interval timer 30 remains reset, counter 18 is at its low count, and pulse generator 12 is at its lower rate limit. if the delay timer has timed out, it produces an output pulse in reponse to the disabling input from the reed switch, thereby resetting the flip - flop, resetting the interval timer, returning counter 18 toward its low count and pulse generator 12 toward its lower rate limit. to that end, delay timer 29 is provided with an internal clock such that, once enabled to time out the delay interval, it cannot be again enabled to do so until the passage of a preselected time interval, which is one hour and fifteen minutes in the present example, unless it has first been disabled during that overall interval. of course, to cancel the exercise rate, the patient must have the magnet available to issue the second command but, as previously noted, once the delay timer is enabled through actuation of the reed switch the magnet may be kept in a convenient location, such as the glove compartment of the patient ' s car, to allow cancellation of the exercise rate in private. although a presently preferred embodiment has been described herein, it will be evident to those skilled in the art that variations and modifications of the preferred embodiment may be carried out without departing from the spirit and scope of the invention. accordingly, it is intended that the present invention shall be limited only to the extent required by the appended claims and the applicable rules of law.


us 5459828 a a method of producing a raster font from a contour font entailing the steps of deriving font metrics and character metrics of font characters in terms of arbitrary font units ; scaling the font characters to a selected size and output resolution ( pixels per unit length ) ; altering the thickness of vertical and horizontal strokes of each character to a desired thickness, from the measured font metrics and character metrics, and including a difference applied to the thickness of the strokes by the printer process, to cause the strokes to be close to an integer number of pixels and thickness and to compensate for thinning and thickening which the printing engine might produce ; bringing the leading and trailing edges of the characters to integer pixel locations, where such locations are based on and scaling the character between the leading and trailing edges proportionally therebetween, and producing a rasterized font from the altered contour font character. 1. a printer processor implemented method for producing a raster font from a contour font defined by a list of points connected by curves, said raster font suitable for printing on a selected printer having known reproduction characteristics, including the steps of : a ) deriving for a contour font a set of font metrics and character metrics of a character in the font defined in terms of arbitrary font units ; b ) scaling a character contour defined in arbitrary font units to a selected size in units of pixels ; c ) altering thickness of character strokes by adjusting vertical and horizontal coordinates of each point defining the character contour in directions defined by a vector normal to the character contour at each point, by an amount required to obtain a desired thickness from the measured font metrics and character metrics, and an amount required to add to difference thickness thereto in accordance with the selected printer reproduction characteristics, said alteration amounts together causing the vertical and horizontal strokes to be sufficiently close to an integer number of pixels or half pixels so as to cause subsequent numerical rounding to produce uniform results across the font ; d ) grid aligning the contour of each character so that leading and trailing edges, and top and bottom edges of the contour of each character fall on whole or half pixel positions ; and e ) applying a rasterization function to the contour to convert each contour font character to a bitmap. 2. the method as defined in claim 1 wherein in said grid alignment step, after aligning said leading and top edges of said contours of each character on a whole pixel position, the length of any


font character to a bitmap. 2. the method as defined in claim 1 wherein in said grid alignment step, after aligning said leading and top edges of said contours of each character on a whole pixel position, the length of any lines joining leading and trailing edges, and lines joining top and bottom edges, are rounded to an integer number of whole or half pixels, and the trailing edge and bottom edges are aligned at whole pixel positions. 3. in a printing system for printing on a selected printer having reproduction characteristics known and available as contour font correction data, wherein a font to be printed has a set of predefined font metrics and character metrics for each character in the font defined in terms of arbitrary font units, the method of preparing a contour font defined by a list of points connected by curves, for printing on the selected printer including the ordered steps of : a ) scaling each character in the contour font to a selected print resolution in pixels per unit length ; b ) altering thickness of character strokes by adjusting vertical and horizontal coordinates of each point defining the contour of each character to a desired thickness in directions defined by a vector, normal to the character contour at each point, by an amount required to obtain a desired thickness from the measured font metrics and character metrics, and an amount required to add a difference thickness thereto in accordance with the contour font correction data for a particular printer, to cause the vertical and horizontal stroke thickness to approximate an integer number of pixels so as to cause subsequent numerical rounding to produce uniform results across the font ; c ) grid aligning the contour of each character so that leading and trailing edges, and top and bottom edges of the contour of each character fall on whole pixel positions ; and d ) applying a rasterization function to the contour convert each contour font character to a bitmap. 4. the method as defined in claim 3 wherein in said grid alignment step, after aligning said leading and top edges of said contours of each character on a whole pixel position, the length of any lines joining leading and trailing edges, and lines joining top and bottom edges, are rounded to an integer number of pixels or half pixels, and the trailing edge and bottom edges are aligned at whole pixel positions. a microfiche appendix, having 5 fiche and 398 frames, is included herewith. the present invention relates generally to the production of raster fonts from contour fonts, and more particularly, to a method of


pixel positions. a microfiche appendix, having 5 fiche and 398 frames, is included herewith. the present invention relates generally to the production of raster fonts from contour fonts, and more particularly, to a method of producing raster fonts from contour fonts taking into account characteristics of the contour font and the printer system which will ultimately print the font. a portion of the disclosure of this patent document contains material which is subject to copyright protection. the copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the patent and trademark office files or records, but otherwise reserves all rights whatsoever. cross reference is made to u. s. patent application ser. no. 07 / 416, 211 by s. marshall, entitled " rapid halfbitting stepper ", and assigned to the same assignee as the present invention. u. s. pat. no. 4, 675, 830 to hawkins is incorporated herein by reference for the purposes of background information on contour fonts. u. s. patent application ser. no. 07 / 416, 211 by s. marshall, entitled " rapid halfbitting stepper ", and assigned to the same assignee as the present invention, is incorporated by reference herein for the purposes of teaching rasterization. " contour fonts " is a term that refers to the use of outlines or contours to describe the shapes of characters used in electronic printing. in a contour font, each character shape is represented by one or more closed curves or paths that traces the boundary of the character. the contour is specified by a series of mathematical equations, which may be in any of several forms, the most common being circular arcs, straight lines, and polynomial expressions. the shape of the contour font is that of the ideal design of the character and, generally, does not depend on parameters associated with any printer. contour fonts are ideal for use as master representations of typefaces. bitmap fonts or raster fonts are composed of the actual characters images that will be printed on a page, and are made by scaling contours to the appropriate size, quantizing or sampling them at the resolution of the printer, and filling the interiors of the characters with black bits or pixels. achieving high quality in this process is difficult, except at very high resolutions, and requires knowledge of both the marking technology and typo


the invention, there is provided a method for conversion of contour fonts to bitmap fonts with automatic thickening and thinning of strokes, and snapping of character edges to pixel or half pixel boundaries. in accordance with the invention, there is provided a method of producing a raster font from a contour font entailing the steps of : first, deriving font metrics and character metrics of font characters in terms of arbitrary font units ; scaling the font characters to a selected size and output resolution ( pixels per unit length ) ; altering the thickness of vertical and horizontal strokes of each character to a desired thickness, from the measured font metrics and character metrics, and including a difference applied to the thickness of the strokes by the printer process, to cause the strokes to be close to an integer number of pixels and thickness and to compensate for thing and thickening which the printing engine might produce ; bringing the leading and trailing edges of the characters to integer pixel locations, where such locations are based on and scaling the character between the leading and trailing edges proportionally therebetween, and producing a rasterized font from the altered contour font character. these and other aspects of the invention will become apparent from the following description used to illustrate a preferred embodiment of the invention in conjunction with the accompanying drawings in which : fig. 1 shows a block diagram of the inventive optimized scaler rasterizer system. figs. 2a - 2e illustrate the development of a raster font from a contour font, using the system described in fig. 1. with reference to the drawing, where the showing is for the purpose of illustrating an embodiment of the invention and not for the purpose of limiting same, the figure shows a block diagram of the present invention which will be referred to and described hereinafter. fig. 1 shows a block diagram of the contour rasterization process of the present invention. beginning with a contour font 10, and with a character " h " shown in contour for illustration purposes at fig. 2a the contour font is analyzed initially at hint generation step 20. at the hint generation, the parameters defining the font are determined, including measurement of the following metrics and character hints : table 1 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ font metric comments _ _ _ _ _ _ _ _ _ _ _


_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ font metric comments _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ cap - height height of the h, i or similar letterx - height height of the lower case xascender height of the lower case k, b, or similar letterdescender position of the bottom of the lower case p or qthickness of upper vertical stroke thicknesscase stems on upper case h or kthickness of upper horizontal stroke oncase cross - strokes upper case e or fthickness of lower vertical stroke thicknesscase stems on lower case k or lthickness of lower case horizontal strokecross - strokes thickness on the fthickness of auxiliarycharacter stemsthickness of auxiliarycharacter cross - strokeshairline thickness thickness of the cross bar on the e or the thin part of the o _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ( see, appendix, page 13, icffontiodefs. mesa ) character hints are generated for each character and include the following : table 2 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ character metric comments _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ position of all horizontal left sides of strokes areedges and indications of leading edges and rightwhether each edge is a sides or strokes areleading or trailing edge. trailing edges. position of all verticaledges and indication ofwhether each edge is aleading or trailing edge. direction of the normalvector ( perpendicular ) to the contour at eachcontrol point in thecontour, pointingtoward the whiteregion. _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ at hint generation 20, the font


which will be obtained after rasterization. this rounding is performed to the nearest whole pixel if half bitting is not enabled and to the nearest half pixel, if half bitting is enabled. there are separate values for horizontal or vertical directions and for upper case, lower case and auxiliary characters. the third component of thickening and thinning applies only to very small characters, and prevents drop - outs of fine lines. this amount is equal to the difference between the calculated scaled thickness of the hairlines, after thickening by the font thickening steps, and the minimum stroke thickness specified in the printer profile. when applied, this thickening brings fine lines up to the value of the minimum stroke thickness. the value is zero if the hairline is already greater than the minimum stroke thickness. ( this process, referred to as " adaptive thickening, " is not disclosed in the source code in the appendix. ) the actual thickening or thinning applied is equal to the sum of these three components. each component has an independent value in the x and y directions. the direction to move each contour control point is specified by its normal vector. the thickened character h is shown at fig. c. at step 60, the snap function or grid alignment function is applied. the coordinate system of the character is varied in the horizontal direction to move vertical and horizontal edges to positions where pixel boundaries will be after rasterization, i. e., to a whole pixel position. this is to assure uniform stroke thickness in the rasterized character images. the process is to piecewise stretch or shrink the character to force edges to align the pixel boundaries. on the left hand sides of the characters, the left edge of each stroke is moved to the closest pixel boundary, while the right edge of the stroke is moved to the pixel boundary specified by rounding the stroke thickness. this process gives priority to maintaining uniform stroke thickness over absolute stroke position. that is to say, that after the left edge of the character has been moved to a whole pixel position, the thickness of the stroke, or portion of the character, is examined to determine its thickness. the thickness has already been adjusted in the thickness of thinning step, so that it is close to a whole pixel width. accordingly, the right edge of the character is then moved to the nearest whole pixel, based on rounding the thickness of the pixel, as opposed to moving the right hand side to the nearest pixel. on the right hand sides of characters, the rolls of left and right edges of strokes are


character is then moved to the nearest whole pixel, based on rounding the thickness of the pixel, as opposed to moving the right hand side to the nearest pixel. on the right hand sides of characters, the rolls of left and right edges of strokes are reversed. right edges of strokes are anchored, while left edges are rounded relatively to corresponding right edges. ( see, appendix, page 355, snap. c ). in one variant of this scheme, the positions of left and right index points or width points, which are those points which determine character spacing and are made to coincide in constructing words, are snapped before the vertical edges. in the vertical direction, snapping is performed to piecewise stretch characters so that positions of baseline, cap - height, x - height, and descender fall on pixel boundaries. baseline and descender position are treated as bottoms of strokes, that is, anchored, while cap - height and x - height are treated as tops of strokes, computed relative to the baseline. all characters are snapped to all of these positions, ensuring uniform character alignment. after these font metric positions are snapped, horizontal edges are snapped in the same manner as vertical edges, with lower edges of strokes anchored and upper edges snapped relative to the lower edges in the lower half of the character and upper edges of strokes anchored and lower edges snapped relative to the upper edges in the upper half of the character. in both horizontal and vertical directions, snapping is performed one edge at a time. that is, the first edge is snapped, stretching the coordinate system of the character slightly on one side of the snapped edge and shrinking it slightly on the other side. the second edge is then snapped, with its pre - snapping position perhaps already modified slightly by the first snap. this sequential snapping helps preserve local character features better than simultaneous snapping of all edges does. when the second edge is snapped, its area of influence on the coordinate grid extends only up to the first snapped edge, which stays in place. this process is then repeated for the remainder of the edges. the snapped character h is shown at fig. 2d. once each character in the adjusted contour font has been placed in the grid and appropriately thickened and thinned, the final step is to sample the adjusted contour on discrete grid. this step 70 can optionally produce half bitted output images, as controlled by the printer profile. light half bitting produces half bitting on curves and diagonals, while heavy half bitting will also produce half bitted vertical and horizontal edges. rasterization in a


- held devices to determine the nature of the source. after the latest round of gao criticism of the dhs technology vetting process, homeland security officials suggested the asp detectors would first be deployed in secondary locations and testing would continue before replacing the plastic scintillators. while belgian port officials have no plans to shift the asp to a primary detection deployment - they say they have the plastic scintillators and might as well use them - the new technology is perfect for secondary screening, they say. " for the second phase, it makes a lot of sense to use the asp, " fias told global security newswire, calling the technology currently " the best on the market. " without the asp detectors, custom officials must use a small, hand - held scanner to assess the entire shipping container. that is a small scanner and a large box, a combination that has led to complaints from customs officials at the port, fias said. by contrast, the asp scanners are " basically a very, very big detector that can scan the whole of the container, " he said. replacing primary scanners with the new technology requires any new device to be at least a sensitive as the plastic scintillators, fias notes, a more challenging bar to meet. the goal with these detector upgrades, both domestically and abroad, is not necessarily increasing the level or radiation detection at ports, but rather smoothing the flow of commerce and making sure current detection regime is not disruptive. u. s. officials have repeatedly said the goal is to lower the number of false alarms at large ports such as los angeles / long beach. that port, the nation ' s busiest, has about 500 radiation alerts a day, and dhs officials suggest the new technology could plunge that number to less than 30. " we want to have a low economic impact. time is money, certainly in a port, " fias said of antwerp. " only 1 in 10, 000 containers are delayed for more than a few hours or days. " he expects the asps, to be used in conjunction with x - ray scanning, to be rolled out in antwerp by the end of next year.


schopf, j. william adult nonfiction qh325. s384 1999 summary : one of the greatest mysteries in reconstructing the history of life on earth has been the apparent absence of fossils dating back more than 550 million years. we have long known that fossils of sophisticated marine life - forms existed at the dawn of the cambrian period, but until recently scientists had found no traces of precambrian fossils. the quest to find such traces began in earnest in the mid - 1960s and culminated in one dramatic moment in 1993 when william schopf identified fossilized microorganisms three and a half " billion years old. this startling find opened up a vast period of time - - some eighty - five percent of earth ' s history - - to new research and new ideas about life ' s beginnings. in this book, william schopf, a pioneer of modern paleobiology, tells for the first time the exciting and fascinating story of the origins and earliest evolution of life and how that story has been unearthed. gracefully blending his personal story of discovery with the basics needed to understand the astonishing science he describes, schopf has produced an introduction to paleobiology for the interested reader as well as a primer for beginning s question about returns, requests or other account details? add a comment