Gestational Diabetes Essay Example for Free

Gestational Diabetes Essay Gestational Diabetes is high glucose (diabetes) that begins or is first analyzed during pregnancy. It is a condition where ladies without recently analyzed diabetes display high blood glucose levels during pregnancy, particularly during third trimester. There is as yet the inquiry whether the condition is normal during pregnancy (Serlin Lash 2009). Causes, Incidence, and Risk Factors Pregnancy hormones can square insulin from carrying out its responsibility. At the point when this occurs, glucose levels may increment in a pregnant women’s blood. You are at more serious hazard for gestational diabetes on the off chance that you: are more established than 25 when you are pregnant, have family ancestry of diabetes, brought forth a child that gauged in excess of 9 pounds or had a birth deformity, have hypertension, have a lot of amniotic liquid, have had an unexplained premature delivery or stillbirth, or were overweight before the pregnancy (Benjamin Pridijan 2010). Side effects Usually there are no side effects, or the indications are gentle and not dangerous to the pregnant lady. The (glucose) level for the most part comes back to typical after conveyance. Side effects may include: obscured vision, weakness, visit contaminations, incorporating those in the bladder, vagina, and skin, expanded thirst, expanded pee, queasiness and regurgitating, and weight reduction notwithstanding expanded craving (Benjamin Pridijan 2010). Signs and Tests Gestational diabetes for the most part begins partially through the pregnancy. Every single pregnant lady ought to get an oral glucose resistance test between the 24th and 28th seven day stretch of pregnancy to screen for the condition. Ladies who have chance variables for gestational diabetes may have this test prior in the pregnancy (Serlin Lash 2009). When you are determined to have gestational diabetes, you can perceive how well you are getting along by testing your glucose level at home. The most widely recognized way includes pricking your finger and putting a drop of blood on a machine that will give you a glucose perusing (Serlin Lash 2009). Treatment The objectives of treatment are to keep (glucose) levels inside ordinary cutoff points during pregnancy, and to ensure that the developing child is solid (Cohen-Almagor R. 2000). Watching the child The social insurance supplier ought to intently check both mother and infant all through the pregnancy. Fetal observing will check the size and strength of the embryo. A nonstress test is a basic, easy test for the mother and infant. A machine that hears and shows the baby’s heartbeat (electronic fetal screen) is put the mother’s midsection. The social insurance supplier can look at the example of the baby’s heartbeat to developments and see if the infant is progressing nicely (Cohen-Almagor R. 2000). Diet and Exercise The most ideal approach to improve the eating routine during pregnancy is by eating well nourishments. The hopeful mother should converse with her primary care physician or dietitian if vegan or on an extraordinary eating regimen. By and large, when determined to have gestational diabetes the eating regimen ought to be moderate in fat and protein, give starches through nourishments that incorporate organic products, vegetables, and complex sugars, for example, bread, grain, pasta, rice. Nourishments that contain a great deal of sugar, for example, sodas, organic product juices and baked goods ought to be maintained a strategic distance from. On the off chance that dealing with the eating routine doesn't control glucose levels, at that point the doctor may endorse diabetes medication by mouth or insulin treatment (American Diabetes Association 2008). Anticipation Most ladies with gestational diabetes can control their glucose and maintain a strategic distance from mischief to themselves or their infant. Pregnant ladies with gestational diabetes will in general have bigger children during childbirth. This can build the opportunity of issues at the hour of conveyance, including: birth (injury) due to the baby’s enormous size, conveyance by c-segment. The child is bound to have times of low glucose (hypoglycemia) during the initial hardly any long stretches of life. Moms with gestational diabetes have an expanded hazard for hypertension during pregnancy. There is a marginally expanded danger of the child kicking the bucket when the mother has untreated gestational diabetes, controlling glucose levels diminishes this hazard (Serlin Lash 2009). High blood glucose levels frequently return to typical after conveyance. Nonetheless, ladies with gestational diabetes ought to be observed intently in the wake of conceiving an offspring and at customary doctor’s arrangements to screen for indications of diabetes. Numerous ladies with gestational diabetes create diabetes inside 5-10 years after conveyance (Serlin Lash 2009). Avoidance Beginning pre-birth care early and having normal pre-birth visits improves the wellbeing of eager mother and her infant. Having pre-birth screening at 24-28 weeks into the pregnancy will help identify gestational diabetes early. In the event that overweight, diminishing BMI to an ordinary range before getting pregnant will diminish the dangers of creating gestational diabetes (Benjamin Pridijan 2010).

How to Write a Blog From Scratch

How to Write a Blog From ScratchEven for experienced writers, writing a blog is not an easy task. Many times it takes a lot of hard work to learn how to write a blog. In this article I will talk about how to write a blog from scratch.The first thing you have to do before you even get started writing a blog is to set your goals. Why do you want to become a writer? Are you looking to make money online, are you looking to publish more than just one post or are you just wanting to start a side business for yourself?One important thing to remember before you start writing is to have a schedule. You need to know how much time you have to write and how often you have to write. Make sure that you also factor in when the traffic will be. If you are going to submit your blog regularly, you need to know how often you have to write each day.Another tip to writing a blog is to make sure you have a post in your blog each week. This way you can get back to your readers and show them your progress e very week. Some people prefer to have one post each week and some people want to keep it interesting by having a few posts a month. Try out a few different styles of writing a blog and find what works best for you.Once you are ready to start writing a blog from scratch, you should go over your outline and decide on the exact layout of your blog. This may sound obvious but make sure you have a good grasp of it before you start. Your blog will only be as good as your outline.A very important element of blogging from scratch is knowing who you are writing for. Do you want to reach a large audience or is your audience a small group of people? Is there a niche in which you want to try your hand? Use these questions to help you narrow down the audience you want to reach.Once you have chosen who you want to do business with, you will be asked to sign up with your online writing service. Make sure you understand exactly what your job is and how you will be paid. Keep in mind that you are pa ying for this service so make sure you know exactly what you are getting for your money. It is important to know that you will be paid in full when you have been doing a certain amount of work for your online writing service.When you have signed up with your online writing service, you will receive a link to your blog and instructions on how to get started. You will then be required to register your blog with them. Make sure you follow the directions closely and you will get started making money blogging within hours.

The Blue Bottle Chemistry Demonstration

Top Chemistry Projects for Bored Kids

Questions On Customer Service Improvements - 1753 Words

BUS-512-03 - 15/SP/A Loredana Carson Hongna Kou Final paper Customer Service Improvements Customer service is a popular study and topic in recent decades. Today, with the development of technology and society, customer service is as important as product quality. Good service plays a very important role in the retail industry, which is reflected by convenience, integrity and caring during transactions. A hierarchical element structure of service quality which is based on five dimensions and twenty-eight attributes has been developed by Dabholkar (Martinelli , E., Balboni, B, 2012). These five dimensions include Personal Interaction, Reliability, Physical Aspects, Policy, and Problem Solving. Not only the physical†¦show more content†¦Researchers indicate that supermarkets should build positive images and prevent failures of service by utilizing a long-term strategy. This service strategy should pay particular intention to the implementation of service process and the setting of store (Martinelli, E., Balboni, B, 2012). Figure1. The competing model (Martinelli , E., Balboni, B, 2012) Table 1. (Martinelli , E., Balboni, B, 2012) So we conclude that grocery retailers form enduring relationship with customers by improving the quality of customer service. Then it will increase customers’ loyalty and expand the long-term business. Therefore, we suggest Vons to improve its customer service in many aspects. First, we suggest Vons use the problem-focused strategies, which include cognition change and situation’s modification, to deal with the customer’s problem. (Little, L. M., Kluemper, D., Nelson, D. L., Ward, A.,2013). The emotion of customer service representatives would seriously impact customer emotion, which is called emotion contagion (Barger PB, Grandey AA., 2006). Published statistics shows that customer service representatives are verbally abused by customers about 10 times a day on average . So some customer service representatives who are subject to these verbal aggression may deal with a customer’s problem ineffectively and lead to damaging consequences. Therefore, we need to identify the harmful

Social Order v. Personal Freedom Essay Example For Students

Social Order v. Personal Freedom Essay A study of Arthur Millers The Crucible and Nathaniel Hawthornes The Scarlet LetterSince the dawn of time, a struggle has been waged. This battle has been fought inthe courtroom, in society, and especially in the human heart. This is the battle betweensocial order and personal freedom. In Arthur Millers The Crucible and NathanielHawthornes The Scarlet Letter this struggle is superbly illustrated. Personal freedom had long been debated in both early Puritan society, during thetime of The Crucible, and later during the time of The Scarlet Letter. When the Puritansfled England in search of religious freedom, they turned first to the Netherlands. Theproblem was, the Dutch permitted much more freedom than the Puritans could reckonwith. The group wanted freedom of religion, as long it was freedom to practice only thePuritan religion. After a failed attempt back in England, the Puritans were given a grantof land in the New World. In this first real exposure to true personal freedom thePuritans rejected it, and this rejection was to set the tone of their lives in the New World. Even when restrictions on dress, manner, and building standards were relaxed, what aperson could or couldnt do in private was still dictated as strictly as ever by the churchtheocracy. Dancing, not attending church, and fighting were all prohibited by thegovernment. Social order, on the other hand, was paramount in these societies. Often one wasexpected simply to recognize what their duty in maintaining the social order was, and todo it. Laws were so strict that neglecting even a single one was considered disorderly andseverely punished. The Crucible and The Scarlet Letter both deal extensively with the fundamentalclash between the desire for freedom by the individual and the desire for order by themasses. Both works deal with the consequences of extramarital affairs. The Puritansociety considered these liaisons a flagrant disregard of the social order imposed on thecommunity. In both works, the participants in these affairs were ruined, but insignificantly different ways. John Proctor, in The Crucible, dies essentially by his ownhand, exchanging the guilt for a sin which he did not commit for that of a sin he didcommit. Proctor: I cannot mount the gibbet like a saint. It is a fraud. I am not that man. . . . My honesty is broke, Elizabeth; I am no good man. Nothings spoiled bygiving them this lie that were not rotten long before. (page 126). Arthur Dimmesdale, in The Scarlet Letter is ruined by his affair with HesterPrynne. A minister in the community, he finds it nearly impossible to live as a hypocrite,preaching goodness and light, and living with the knowledge that he is not an innocentindividual. Live he does, however, but the strain of his conscious wears away at him. Heloses all joy in life, constantly clutching at his heart under the weight of his sin. Dimmesdale wastes away slowly, fighting the knowledge of his sin, while that sameknowledge eats at his will to live. On that spot, in very truth, there was, and there had long been, the gnawing andpoisonous tooth of bodily pain. Without any effort of his will or power to restrainhimself, he shrieked aloud; an outcry that . . . reverberated . . . as if a company ofdevils, detecting so much misery and terror in it, had made a plaything of thesound . . . (page 144)Each of these two men, having waged an internal battle between social order andpersonal freedom, succumbed to personal freedom, and were destroyed for it in their ownattempts to the right their sins. Although the manners of their deaths were different, bothmen die from guilt after disobeying the social order of the day. .ud66abccd43c4119db0cbbd3ea0aa70a7 , .ud66abccd43c4119db0cbbd3ea0aa70a7 .postImageUrl , .ud66abccd43c4119db0cbbd3ea0aa70a7 .centered-text-area { min-height: 80px; position: relative; } .ud66abccd43c4119db0cbbd3ea0aa70a7 , .ud66abccd43c4119db0cbbd3ea0aa70a7:hover , .ud66abccd43c4119db0cbbd3ea0aa70a7:visited , .ud66abccd43c4119db0cbbd3ea0aa70a7:active { border:0!important; } .ud66abccd43c4119db0cbbd3ea0aa70a7 .clearfix:after { content: ""; display: table; clear: both; } .ud66abccd43c4119db0cbbd3ea0aa70a7 { display: block; transition: background-color 250ms; webkit-transition: background-color 250ms; width: 100%; opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #95A5A6; } .ud66abccd43c4119db0cbbd3ea0aa70a7:active , .ud66abccd43c4119db0cbbd3ea0aa70a7:hover { opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #2C3E50; } .ud66abccd43c4119db0cbbd3ea0aa70a7 .centered-text-area { width: 100%; position: relative ; } .ud66abccd43c4119db0cbbd3ea0aa70a7 .ctaText { border-bottom: 0 solid #fff; color: #2980B9; font-size: 16px; font-weight: bold; margin: 0; padding: 0; text-decoration: underline; } .ud66abccd43c4119db0cbbd3ea0aa70a7 .postTitle { color: #FFFFFF; font-size: 16px; font-weight: 600; margin: 0; padding: 0; width: 100%; } .ud66abccd43c4119db0cbbd3ea0aa70a7 .ctaButton { background-color: #7F8C8D!important; color: #2980B9; border: none; border-radius: 3px; box-shadow: none; font-size: 14px; font-weight: bold; line-height: 26px; moz-border-radius: 3px; text-align: center; text-decoration: none; text-shadow: none; width: 80px; min-height: 80px; background: url(https://artscolumbia.org/wp-content/plugins/intelly-related-posts/assets/images/simple-arrow.png)no-repeat; position: absolute; right: 0; top: 0; } .ud66abccd43c4119db0cbbd3ea0aa70a7:hover .ctaButton { background-color: #34495E!important; } .ud66abccd43c4119db0cbbd3ea0aa70a7 .centered-text { display: table; height: 80px; padding-left : 18px; top: 0; } .ud66abccd43c4119db0cbbd3ea0aa70a7 .ud66abccd43c4119db0cbbd3ea0aa70a7-content { display: table-cell; margin: 0; padding: 0; padding-right: 108px; position: relative; vertical-align: middle; width: 100%; } .ud66abccd43c4119db0cbbd3ea0aa70a7:after { content: ""; display: block; clear: both; } READ: Wolfgang Amadeus Mozart Essay SummaryBoth The Crucible and The Scarlet Letter deal with a conflict emerges betweenthe two desires when a citizen takes vengeance upon themselves, rather than taking theirgrievances to the law. In The Crucible, Abigail Williams targets John Proctor and hisfamily after he leaves her and ends an affair between the two of them. By taking the lawinto her own hands, Abigail violates the social system of the community, bringing allsemblance of order crashing down around her own personal schemes. This is illustratedby Proctors statement when he attempts to clear his wife of the accusation of witchcraft. Proctor: . . . She Abigail thinks to dance with me on my wifes grave! . . . Godhelp me, I lusted, and there is such a promise in sweat. But it is a whoresvengeance, and you must see it . . . (page 102). In The Scarlet Letter, Hester Prynnes betrayed husband, Roger Chillingworth,vows vengeance on her and her lover, Arthur Dimmesdale, for their perfidy and disregardfor him. By taking vengeance into his own hands, he circumvents the law and destroysone mans regard for himself in the process. But, as for me, I come to the inquest with other senses than they possess. I shallseek this man. . . . There is a sympathy in him that will make me conscious of him. . . . I shall feel my self shudder, suddenly and unaware. Sooner or later, he mustneeds be mine! (page 80). Once again, the disregard for the social order of the community destroys theavengers. In The Crucible, Parris announces:My niece, sir, my niece Abigail I believe she has vanished. . . . Excellency, Ithink they may be aboard a ship. . . . Tonight I discover my strongbox is brokeinto. (page 174)Legend says Abigail Williams became a prostitute in Boston, ruined by her need todestroy the Proctors. Roger Chillingworths vengeance also proved disastrous. When ReverendDimmesdale confesses, Chillingworths last reason to live is stolen from him. The doctordies one year later, a broken man. During that year, Chillingworth lives under a spoiledreputation, accused of being . . . a potent necromancer, who had caused it the scarletletter to appear through the agency of magic and potent drugs . . . (page 240) to appearon Arthur Dimmesdales breast in the years the two were house-mates. It is said thatduring the year he lived all his vital and intellectual force seemed at once to desert him;insomuch that he positively withered up, shriveled away, and almost vanished frommortal sight, like an uprooted weed that lies wilting in the sun. (page 242). HadChillingworth acknowledged himself as Hesters husband, gone to the authorities of thetown with his suspicions, and generally abided by the rules set forth by society, it isdoubtful that he would have met such an end. By disregarding the order of society,however, he brought only misery and no justice to himself, and the lovers. A conflict, however, is also present between the two pieces on the subject of socialorder and personal freedom. The society of The Scarlet Letter is much less daunting thanthat of The Crucible. The fact that Hesters embroidery was widely in demand denotes aculture far more lenient than that described in The Crucible. Governor Bellinghamsgloves, the scarves Hester embroiders for ladies, and the dress she makes for Pearl are allindications of the beginnings of modern society. Deep ruffs, painfully wrought bands and gorgeously embroidered gloves were alldeemed necessary . . . . In the array of funerals, too, whether for the apparel of thedead body, or to typifiy, by manifold emblematic devices of sable cloth and snowylawn, there was a frequent and characteristic demand . . . . Baby linen, for babiesthen wore robes of state, afforded still another possibility of toil and emolument. .u013ca5b4d72504fe4c1300658c364cf3 , .u013ca5b4d72504fe4c1300658c364cf3 .postImageUrl , .u013ca5b4d72504fe4c1300658c364cf3 .centered-text-area { min-height: 80px; position: relative; } .u013ca5b4d72504fe4c1300658c364cf3 , .u013ca5b4d72504fe4c1300658c364cf3:hover , .u013ca5b4d72504fe4c1300658c364cf3:visited , .u013ca5b4d72504fe4c1300658c364cf3:active { border:0!important; } .u013ca5b4d72504fe4c1300658c364cf3 .clearfix:after { content: ""; display: table; clear: both; } .u013ca5b4d72504fe4c1300658c364cf3 { display: block; transition: background-color 250ms; webkit-transition: background-color 250ms; width: 100%; opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #95A5A6; } .u013ca5b4d72504fe4c1300658c364cf3:active , .u013ca5b4d72504fe4c1300658c364cf3:hover { opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #2C3E50; } .u013ca5b4d72504fe4c1300658c364cf3 .centered-text-area { width: 100%; position: relative ; } .u013ca5b4d72504fe4c1300658c364cf3 .ctaText { border-bottom: 0 solid #fff; color: #2980B9; font-size: 16px; font-weight: bold; margin: 0; padding: 0; text-decoration: underline; } .u013ca5b4d72504fe4c1300658c364cf3 .postTitle { color: #FFFFFF; font-size: 16px; font-weight: 600; margin: 0; padding: 0; width: 100%; } .u013ca5b4d72504fe4c1300658c364cf3 .ctaButton { background-color: #7F8C8D!important; color: #2980B9; border: none; border-radius: 3px; box-shadow: none; font-size: 14px; font-weight: bold; line-height: 26px; moz-border-radius: 3px; text-align: center; text-decoration: none; text-shadow: none; width: 80px; min-height: 80px; background: url(https://artscolumbia.org/wp-content/plugins/intelly-related-posts/assets/images/simple-arrow.png)no-repeat; position: absolute; right: 0; top: 0; } .u013ca5b4d72504fe4c1300658c364cf3:hover .ctaButton { background-color: #34495E!important; } .u013ca5b4d72504fe4c1300658c364cf3 .centered-text { display: table; height: 80px; padding-left : 18px; top: 0; } .u013ca5b4d72504fe4c1300658c364cf3 .u013ca5b4d72504fe4c1300658c364cf3-content { display: table-cell; margin: 0; padding: 0; padding-right: 108px; position: relative; vertical-align: middle; width: 100%; } .u013ca5b4d72504fe4c1300658c364cf3:after { content: ""; display: block; clear: both; } READ: Popular Entertainment, Performing Arts Essay(page 86)The festival held on Election Day as described in The Scarlet Letter would havebeen pure heresy to the inhabitants of Salem Village; mariners, granted special license bythe citizens of Boston, would have been expected to conform to Puritan society while onshore had they sailed into Salem. The picture of human life in the market place, though its general tint was the sadgray, brown, or black of the English emigrants, was yet enlivened by somediversity of hue. A party of Indians, in their savage finery of curiouslyembroidered deerskin robes, wampum belts, red and yellow ochre, and feathers . . . . Nor, wild as were these painted barbarians, were they the wildest feature of thescene. This distinction could . . . be claimed by some mariners . . . who had comeashore to see the humors of Election Day. They were rough-looking desperadoeswith sun-blackened faces and an immensity of beard; their wide, short trouserswere confined about the waist by belts, often clasped with a rough plate of goldand sustaining always a long knife, and, in some instances a sword. From beneaththeir broad-brimmed hats of palm leaf gleamed eyes which . . . had a kind ofanimal ferocity. (page 218). In this sense the characters of The Scarlet Letter have a much greater personal freedom,and less strict social order, than do those of The Crucible. The struggle between personal freedom and social order has been fought in everysociety, and in every human heart throughout the ages. The Scarlet Letter and TheCrucible illustrate this struggle superbly, not only granting the reader a glimpse at therestrictions on freedom in place during the Puritan era, but also illustrating the differencebetween the freedoms available in a small village or large town. This struggle continuestoday, with much the same consequences when social order is disregarded as there werethen.

Pi Number Essays - Pi, Approximations Of, , Term Papers

Pi Number A little known verse in the bible reads "And he made a molten sea, ten cubits from the one brim to the other; it was round all about, and his height was five cubits; and a line of thirty cubits did compass it about (I Kings 7, 23)." This passage from the bible demonstrates the ancient nature of the irrational number pi. Pi in fact is mentioned in a number of verses throughout the bible. In II Chronicles 4,2, in the passage describing the building of the great temple of Solomon which was built around 950BC, pi is given as equal to three. This value is not very accurate at all and should not even be considered accurate for it's time, however it should be noted that precision was not needed for the task that was being performed and we should let the general concept of pi that the biblical characters posses impress us. Present knowledge suggests that the concept of pi first developed in 2000 BC in two separate cultures. The Babylonians used pi at a value of 25/8 while an entirely different culture, the ancient Egyptians used pi at a value of 256/81. While the biblical calculation of pi=3 most likely came from crude measurement, there is strong reason to believe, because of the relative accuracy of the values, that the Babylonians and Egyptians found pi by means of mathematical equations. In the Egyptian Rhind Papyrus, which is dated around 1650 BC, there is strong evidence supporting that the Egyptians used 4(8/9)2 =3.16 for their value of pi. At that point in history, and for the majority of modern history, pi was not seen as an irrational number as it is today. The next culture that investigated pi was the ancient Greeks. Starting in 434 BC Greeks were unraveling the mysteries of pi. The mathematician Anaxagoras made an unsuccessful attempt at finding pi, which he called squaring the circle and in 414 BC, 20 years after Anaxagoras failed in his attempt to square the circle, Aristophanes refers to the work of Anaxagoras in his comedy "The Birds". It took over 100 years for the Greeks to finally find a value for pi. In 240 BC Archimedes of Syracuse showed that 223/71*pi*22/7. Archimedes knew, what so many people today do not, that pi does not equal 22/7 and he made no claim to have discovered the exact value of pi. However if we take the average of his two bounds we obtain pi=3.1418, which was an error of about 0.0002. Archimedes found the most accurate value of pi up to that time and his value would be used exclusively until the next discovery in the world of pi. The next major finding concerning pi did not occur in the western world, but in China by Tsu Chung-chi'h who approximated pi at 355/113 in 480 AD. Next to nothing except for this work is known about Tsu Chung-chi'h's life but it is very unlikely that he had any awareness of Archimedes work. We shall now notice how during the dark ages of Europe, the lead in the research of pi is passed to the East. Aryabhata, working on his own in Persia without any outside information in 515 AD was able to approximate pi to 3 decimal places. A mathematician from Baghdad named Al'Khwarizimi worked with pi however the most accurate finding of pi to date was found even more east in Samarkand by Al-Khashi. In 1430 AD he approximated pi to 16 decimal places, the most to date. His work however, would be the last of note from the east as the European Renaissance brought about a whole new mathematical world. The first notable discovery in the approximation of pi from the European Renaissance was by Viete in 1593 AD. He expressed pi as an infinite product by using only 2's and square roots. In 1610 Ludolph van Ceulen demonstrated the new thought coming out of the Renaissance by calculating pi to 35 decimal places. Around the same time, Snell refined Archimedes's method of calculating pi, and Snell's work was used by Grienberger to calculate pi to 39 decimal places in 1630. In 1655 Wallis showed that pi/2=2/1*2/3*4/3*4/5*6/5*6/7*8/7*8/9..... The 18th centuary brought about great achievements in the calculating of pi. In 1706, Machin found pi to 100 decimal places, the first time that feat was ever achieved and in the same year, a British mathematician, William Jones first used pi for the circle ratio. In 1737, Euler first used the Greek letter pi