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Understanding the Features of Finance: A Guide for Newbies Finance is a broad field that involves managing money, including activities such as investing, borrowing, lending, budgeting, saving, and forecasting. As a beginner, understanding the basic features of finance is crucial. This guide will relate these features to blockchain technology, cryptocurrency, and decentralized finance (DeFi). 1. Basic Financial Concepts Investing: Putting money into assets like stocks, bonds, or real estate with the expectation of earning a return. In the blockchain world, this translates to investing in cryptocurrencies like Bitcoin, Ethereum, or various DeFi projects. Borrowing and Lending: Traditional finance involves banks and financial institutions providing loans. In the DeFi space, platforms like Aave and Compound allow users to borrow and lend cryptocurrencies without intermediaries. Budgeting: Planning how to allocate your income to cover expenses, save, and invest. Using blockchain technology, you can utilize smart contracts to automate budgeting and savings processes. 2. Blockchain Technology Blockchain is a decentralized ledger that records transactions across multiple computers. It is the technology behind cryptocurrencies and has several key features: Transparency: All transactions are recorded on a public ledger, making them visible to anyone. Security: Cryptographic techniques ensure that data on the blockchain is secure and tamper-proof. Decentralization: No single entity controls the blockchain, reducing the risk of centralized control and failure. 3. Cryptocurrencies Cryptocurrencies are digital or virtual currencies that use cryptography for security. They operate on blockchain technology and offer several advantages: Lower Transaction Costs: Sending money across borders is cheaper with cryptocurrencies compared to traditional banking methods. Accessibility: Anyone with an internet connection can access cryptocurrencies, promoting financial inclusion. Ownership and Control: Users have complete control over their funds without relying on banks. 4. Decentralized Finance (DeFi) DeFi is a movement that uses blockchain technology to recreate and improve traditional financial systems in a decentralized manner. Key features of DeFi include: Smart Contracts: Self-executing contracts with the terms directly written into code, enabling trustless and automated transactions. Liquidity Pools: Users can provide their assets to a pool and earn interest or rewards, promoting liquidity in the DeFi ecosystem. Yield Farming: A strategy where users move their assets between different DeFi platforms to maximize returns. 5. Applications in DeFi and Blockchain HaloFi Save: A platform that leverages blockchain technology to help people save money efficiently and securely. It encourages users to save larger amounts for longer durations, offering higher interest rates compared to traditional banks. Non-Custodial Savings: Users have full control over their funds, reducing the risk of losing their money to institutional failures or fraud. Access to DeFi: Integrating with DeFi platforms like Moola Market, HaloFi Save provides additional opportunities to earn interest on savings, promoting financial growth and stability. Practical Example: A Farmer's Journey Imagine a farmer in a remote village in Africa. Traditionally, this farmer might not have access to banking services, making it difficult to save money, get loans, or invest in better farming equipment. With platforms like HaloFi Save, the farmer can: Save money securely and earn interest. Access microloans through DeFi platforms integrated with Celo. Participate in educational programs to learn more about blockchain and DeFi. Conclusion Blockchain technology, through platforms like HaloFi Save and initiatives by Celo Africa DAO, has the potential to drive significant social change by promoting financial inclusion, transparency, and access to resources. By empowering individuals and communities with the tools and knowledge to participate in the digital economy, blockchain can help address global issues and foster sustainable development.
Nutrition Notes Nutrition- study of how your body uses food Process by which body uses nutrients How you look and feel Resist diseases and illness How you perform physically and mentally Nutrients: substances in food your body needs to grow, repair and supply energy to your body cells 6 Classes of Nutrients 1.Carbohydrates: 1 gram= 4 calories 2. Protein: 1 gram- 4 calories 3. Fats: 1 gram= 9 calories 4.Water 5. Vitamins 6. Minerals Calorie: measurement of energy in food Metabolism: Rate at which body burns energy(calories) Hunger: physical drive to eat Appetite: pshycological desire for food What influences your food choices: Foods you like Health Reasons Family and Culture Time & Money Advertising Emotions Friends Social Media: Modeling Nutrients Carbohydrates: your body’s main source of energy sugars/starches in food 45%-65% of diet #1 source of energy Simple: sugars converted to glucose= energy (fruits, dairy, honey, some manufactured foods) Complex: sugars linked together (starches) (grains, bread, pasta, beans, vegetables) Fiber: tough, indigestible carbohydrates Cleans our digestive system Prevents some types of cancer Prevents heart disease (fruits, vegetables, whole grains,nuts) 2. Protein: growth and repair of body tissues Made up of chemicals called “amino acids” Basic building material of all body cells (muscles, bones, skin, internal organs) Secondary source of energy protein(hemoglobin) attaches to oxygen in blood Functions as hormones regulating body functions 10-15% of diet *Body uses 20 Amino Acids found in food ( body produces 11 and 9 must come from diet) Essential amino acids: 9 amino acids body doesn't produce Complete Amino Acids: foods that contain all 9 essential amino acids ( animal products) Incomplete Amino Acids: food products that do not contain all 9 essential amino acids. Fats 15-25% of diet Secondary source of energy Blood clotting Controlling inflammation Maintains healthy skin/hair absorb /transport fat soluble vitamins Regulates body temperature Types of Fat Unsaturated: “good” fat Liquid at room temperature Can help fight heart disease (veg oil, nuts) Saturated: “bad” fat Solid at room temp Clogs arteries Causes strokes, heart attack, diabetes (animal products, meat, dairy) Cholesterol: waxy like fat substance found in meat products HDL: good type of cholesterol Body creates(liver) Creates cell wall, hormones, and vit D LDL: bad cholesterol- found in foods (clogs arteries) 4. Trans Fat: “one of the worst type of fats” Formed by a process called “hydrogenation”: adding Hydrogen molecules to unsaturated fats to make it more solid and resistant to chemical change. Vitamins A vitamin is a chemical compound that is needed in small amounts for the human body to work correctly. Vitamins are classified as either fat soluble (vitamins A, D, E and K) or water soluble (vitamins B and C). This difference between the two groups is very important. It determines how each vitamin acts within the body. The fat soluble vitamins are soluble in lipids (fats). Fat soluble vitamins can be stored in our body Water soluble vitamins must be taken every day Human body produces some amounts of Vitamin D & K
Make mcq quiz with 4 option in which one is correct -'10 Basis of Material Science • .....;;;";;;"~~;;,,;;,,,,;.;.,,;;,,,;,,;.;,.,------------ 6. Temporary materials: Some materials are meant to be placed in the oral cavity for a short period of time for different reasons. • Temporary crowns: While a permanent crown is prepared in the dental laboratory, the patient must wait for few days before it can be fabricated and cemented into place. Does patient experience any problems during this time period? If the tooth is vital (the pulp is alive), the patient is likely to experience pain and sensitivity while eating and drinking, also it looks unesthetic. What can be done to solve this problem? A temporary crown is placed before the patient leaves the clinic. It is constructed and luted in the same appointment in which the crown preparation is done. Temporary crowns are not very strong or esthetic but they serve adequately till the permanent crown is ready to be cemented. • Temporary restorations: Sometimes it is difficult to decide immediately the best line of treatment for a particular tooth. The exact condition of the pulp may not be obvious to the dentist from the patient's symptoms. A dentist removes all or part of the decay and then places a temporary restoration to have time to observe the behaviour of the pulp or to give the pilip time to heal before deciding the further treatment required. Classification based on Location of Fabrication 4,9 Materials can be classified based on the location of fabrication into: • Direct restorative materials. • Indirect restorative materials Direct restorative materials: They include those materials which are used to restore cavity preparations directly in the oral cavity (Box 1.5). Box 1.5: Examples of direct restorative materials Amalgam, composites, glass ionomer and other materials, which set by chemical reactions in the mouth. Indirect restorative materials: It includes those restorations which must be fabricated outside the mouth, indirectly on a cast/ model/ die, because their processing condition would harm oral tissues. Materials used in the construction of such prosthesis are called indirect restorative materials (Box 1.6). Box 1.6: Examples of indirect restorative materials Gold inlays, crowns of metal, ceramic and polymers, which are processed at elevated temperatures. Some indirect composite restorations can be processed under specific wavelength of light, e.g. Ceramage. Classification based on Longevity of Use 1. Permanent restorations: These restorations are not planned to be replaced for a particular time period. Though they are referred to as permanent, actually they are not, e.g. fillings, crowns, bridges and dentures do not last forever (Fig. 1.5). 2. Temporary restorations: These restorations are planned to be replaced in a short period of time, such as few days to weeks. For ~ Permanent C/) c c -.2 0 c- :;::; Cll co Interim ~ Q; 0 .8ll::1iJ C/) o~ Cll a:: c:=:J Temporary Time period Fig. 1.5: Diagram depicting the time period of use of a restoration. (Arrow in permanent restoration depicts that such restorations are not planned to be replaced for a long period of time.) Introducton to Dental Materials Dental materials Box 1.7: Characteristics of metals 1. High thermal and electrical conductivity 2. Ductility (pure metals are very soft and they can be bent without breaking) 3. Opacity (they do not transmit light) 4. Luster (they have a surface that strongly reflects light and appears bright and shiny) 5. They tend to dissolve to some extent in water or other aqueous solutions, producing cations. 6. All metals are white (actually gray) except for gold, which is yellow, and copper, which is reddish. 7. All metals are solid at room temperature except mercury, which is liquid at room temperature and is used with silver alloys as amalgam. 8. All metals have high melting temperatures because of high strength of the metallic bond that holds the atoms together. 3. Polymers 4. Composites Composites are mixtures of two or more of the first three classes in which the different components remain distinct from one another in the final structure. A common example is composite resin. Fig. 1.7a: Three-dimensional structure of iron (metal) Metals Metals are the oldest of the three classes of materials that have been used as dental materials. Metals are characterized by metallic bonds (Box 1.7) which will be discussed in the next chapter. Metals solidify with their atoms in a regular or crystalline arrangement (see Chapter 2), often in the form of a cube (Fig. 1.7a). example, temporary fillings done in a tooth during root canal treatment, which have to be replaced within 2-4 days during subsequent visits. They are used to protect the tooth and provide function till the final restoration is done. 3. Interim restoration: At times, dental treatment requires "long-term" definite temporary restorations or "interim" restorations. For examle, a 7-year-old child, met with trauma and fractured one of his central incisors. A large composite build- up may serve his immediate requirement until the root formation is completed and a permanent crown is placed. 5 Classification based on the Chemical Nature of the Material These are the atoms that make up a material and the way they are bonded together determine the properties of that materiaLS Weak bonds make for weak materials and vice versa (Table 1.4). Materials can be classified into different categories based on their primary atomic bonds (Fig. 1.6): 1. Metals 2. Ceramics Fig. 1.6: Classification of dental materials based on chemical nature 12 Basis of Material Science Box 1.9: Benefits of ceramics in dentistry 1. Many ceramic oxides are used as pigmenting agents. These oxides produce good range of colors. Due to this characteristic, we are able to match almost any tooth color with good esthetic results. 2. They are inert, i.e. not chemically reactive. This quality provides ceramics with good bio- compatibility. 3. Ceramic materials are translucent, like natural teeth. This translucency gives the ceramic crown a more natural appearance than any other dental material. Fig. 1.7b: Internal arrangement of tetrahedral structure of ceramic (silica) four large oxygen atoms surround smaller silicon atom Ceramics A ceramic is a compound formed by the union of a metallic and a non-metallic element (Box 1.8). Most of these materials are oxides, formed by the union of oxygen with metals such as silicon, aluminum, calcium and magnesium (Fig.1.7b). Ceramics may be simple or complex. Examples of simple ceramics are alumina and silica. Examples of complex ceramics are feldspar (potassium aluminum silicate) and kaolin (hydrated aluminum silicate). Ceramics may be crystalline or non- crystalline (i.e. amorphous). Porcelain is a specific type of ceramic used extensively in dentistry (Box 1.9). Box 1.8: Characteristics of ceramics 1. High melting points. 2. Brittleness, which means they cannot be bent or deformed (no sliding) to any extent without actually cracking and breaking. 3. They are poor conductor of heat and electricity. 4. They are chemically inert. 5. They have excellent esthetic result in terms of matching natural teeth. Fig. 1.8: Stucture of synthetic polymer Polymers They are the latest addition (early to mid- 1900s) to dental materials. Most of the polymers are nowadays synthesized by humans. Polymers are giant, long-chain organic molecules (Fig. 1.8). Polymers are characterized by covalent bonds within each molecule, giving them tremendous strength in a single direction. Try to break a nylon rope by pulling it! They are poor conductors of heat and electri- city. Most polymers have a structure containing thousands of carbon atoms linked together like beads on a string. Others, such as silicone polymers are formed with silicon-oxygen bonds. Introducton to Dental Materials Table 1.4: Characteristics of different materials 13 Characteristics Bond Properties Crystal structure Metals Metallic bonding High strength and hardness, high electrical and thermal conductivity BCC, FCC, or HCP unit cells Ceramics Ionic or covalent bonding, or both High hardness and stiffness, electrically insulating, refractory, and chemically inert Crystalline or amorphous Polymers Covalent bonding Low sensitivity, high electrical resistivity, and low thermal conductivity, strength and stiffness vary widely Amorphous and crystalline Composites Composites are combinations of any of the basic ceramic, metallic and polymeric materials (Box 1.10). Each material that makes up composites is called a phase. Their properties tend to be somewhere between those of their basic constituents and are used to enhance their performance, longevity and handling chracterstics. Box 1.10: Types of composites in dentistry 1. Ceramic - metallic composite: Tungsten carbide bur. 2. Metal - polymer composite: Die materials in dental laboratory. 3. Ceramic - polymer composite: Enamel, dentin, bone and restorative composites. A composite is a kind of "combination" of materials, which compliment each other. The properties lacking in one material are compensated by those of the other material. For example, restorative composite has two phases, namely resin and fillers. Teeth and bones are examples of natural composites. Enamel is a composite of hydroxyapatite (which is a ceramic material) and protein (which is a polymer). EVALUATION OF DENTAL MATERIALS Most manufacturers of dental materials maintain a quality assurance programme (As per international standard like ADA specifications) and materials are thoroughly tested before being released into the market for dental practitioner (Fig. 1.9). Laboratory Evaluations Most ADA/ ANSI specifications involve laboratory tests. The tests performed as per these specifications are useful but they all are performed in vitro, (carried out in the laboratory away from the clinical conditions) which have a lot of limitations in clinical practice.lO Clinical Notes 1. For example, most of the direct restorative materials are tested for their compressive strength but ultimately the material is subjected to a combination of compressive, tensile and shear stresses, which may decide the final success or failure of the material under masticatory load. 2. Similarly upper dentures mostly fracture along the midline because of bending. Hence a bending or transverse strength ~B-a-s-is-o-f-M-a-t-e-ria-I-S~c-ie-n-c-e-------------- ---------. test is far more meaningful for denture base materials than a compression test. Clinical Trials The majority of new materials are subjected to extensive clinical trials normally in co-operation with a dental college or hospital departments prior to their release. CONCLUSION As the number of available materials is going up, it is important that the dentist remains more aware about new products so that their judgement about the selection of material remains successful. Materials which have not been thoroughly evaluated should be avoided, specially with clinical dentistry falling under Consumer Protection Act (CPA). I Research and development I iI Manufacturer/analysis Ideal requirements for clinical use: Thermal, optical, mechanical, chemical, biological Available materials and their properties are evaluated Launch of new I product Choice and selection of material by the dentist Critical assessment based on clinical performance I I H feedback to I
Acetic acid – a chemical substance with an inhibiting effect on the growth of microorganisms and which is present in vinegar.Acetic Acid Fermentation Fermentation preserves food through the metabolic activities of selected groups of microorganisms. During the process, compounds such as lactic acid, acetic acid and alcohol are developed and result in a more or less stable food form. It makes food more nutritious as dietary source of proteins, vitamins and minerals.Vinegar is an example of the product of acetic acid fermentation which also undergoes alcoholic fermentation to complete the process.Filter – is a device, substance (like paper or charcoal), or process that separates unwanted components from a fluid Cheesecloth-is a loose-woven, gauze-like cotton fabric used for straining liquids from solids.Decant- gradually pour (liquid, typically wine or a solution) from one container into another, especially without disturbing the sediment. Sediment-is solid material (like sand, silt, clay, rocks, organic matter) broken down by weathering, transported by wind, water, or ice, and deposited in a new location, settling at the bottom of water bodies or on land.How to make vinegar?1.Grind or crash the fruit, then boil in water of the same amount as the ground flesh, peels and cores. Boil until soft, and then strain the juice through a cheesecloth2.Add ÂĽ (one-fourth) pound of sugar for every liter of juice extracted from fruit peels and cores. Do not add sugar when using ripe fruit.3.Add ÂĽ of a cake of fresh yeast that has been well-broken up, for every liter of juice. Stir very well, and then place in glass jars. Cover with a clean cloth and let the mixture stand for about two weeks .4. After two weeks, separate the clear liquid from the sediment. Prepare fresh, unpasteurized vinegar also called “mother vinegar” which is the white gummy mass that usually forms in vinegar. Add this to the liquid and mix very well. Over the container with cloth, then allow to stand in a warm place until it has acquired a flavor strong enough to use.5.Filter the clear liquids, then pour in a bottle and cover tightly.USES OF VINEGAR1. Insect salve and repellent. 2. Kill weeds and remove ants. 3. Enhance bricks. 4.Open a tight jar. 5.Clean scissors. 6.Remove smoke odors. 7. Remove pit stains. 8. Make hair shine. 9. Fruit fly trap. 10. Car care.Â
What do an ancient Greek philosopher and a 19th century Quaker have in common with Nobel Prize-winning scientists? Although they are separated over 2,400 years of history, each of them contributed to answering the eternal question: what is stuff made of? It was around 440 BCE that Democritus first proposed that everything in the world was made up of tiny particles surrounded by empty space. And he even speculated that they vary in size and shape depending on the substance they compose. He called these particles "atomos," Greek for indivisible. His ideas were opposed by the more popular philosophers of his day. Aristotle, for instance, disagreed completely, stating instead that matter was made of four elements: earth, wind, water and fire, and most later scientists followed suit. Atoms would remain all but forgotten until 1808, when a Quaker teacher named John Dalton sought to challenge Aristotelian theory. Whereas Democritus's atomism had been purely theoretical, Dalton showed that common substances always broke down into the same elements in the same proportions. He concluded that the various compounds were combinations of atoms of different elements, each of a particular size and mass that could neither be created nor destroyed. Though he received many honors for his work, as a Quaker, Dalton lived modestly until the end of his days. Atomic theory was now accepted by the scientific community, but the next major advancement would not come until nearly a century later with the physicist J.J. Thompson's 1897 discovery of the electron. In what we might call the chocolate chip cookie model of the atom, he showed atoms as uniformly packed spheres of positive matter filled with negatively charged electrons. Thompson won a Nobel Prize in 1906 for his electron discovery, but his model of the atom didn't stick around long. This was because he happened to have some pretty smart students, including a certain Ernest Rutherford, who would become known as the father of the nuclear age. While studying the effects of X-rays on gases, Rutherford decided to investigate atoms more closely by shooting small, positively charged alpha particles at a sheet of gold foil. Under Thompson's model, the atom's thinly dispersed positive charge would not be enough to deflect the particles in any one place. The effect would have been like a bunch of tennis balls punching through a thin paper screen. But while most of the particles did pass through, some bounced right back, suggesting that the foil was more like a thick net with a very large mesh. Rutherford concluded that atoms consisted largely of empty space with just a few electrons, while most of the mass was concentrated in the center, which he termed the nucleus. The alpha particles passed through the gaps but bounced back from the dense, positively charged nucleus. But the atomic theory wasn't complete just yet. In 1913, another of Thompson's students by the name of Niels Bohr expanded on Rutherford's nuclear model. Drawing on earlier work by Max Planck and Albert Einstein he stipulated that electrons orbit the nucleus at fixed energies and distances, able to jump from one level to another, but not to exist in the space between. Bohr's planetary model took center stage, but soon, it too encountered some complications. Experiments had shown that rather than simply being discrete particles, electrons simultaneously behaved like waves, not being confined to a particular point in space. And in formulating his famous uncertainty principle, Werner Heisenberg showed it was impossible to determine both the exact position and speed of electrons as they moved around an atom. The idea that electrons cannot be pinpointed but exist within a range of possible locations gave rise to the current quantum model of the atom, a fascinating theory with a whole new set of complexities whose implications have yet to be fully grasped. Even though our understanding of atoms keeps changing, the basic fact of atoms remains, so let's celebrate the triumph of atomic theory with some fireworks. As electrons circling an atom shift between energy levels, they absorb or release energy in the form of specific wavelengths of light, resulting in all the marvelous colors we see. And we can imagine Democritus watching from somewhere, satisfied that over two millennia later, he turned out to have been right all along.
Nutrition, Metabolism, and Body Temperature Regulation. Nutrient is a substance that promotes normal growth, maintenance, and repair. Major nutrients are carbohydrates, lipids, and proteins. Other nutrients include vitamins and minerals (and technically speaking, water).Complex carbohydrates (starches) are found in bread, cereal, flour, pasta, nuts, and potatoes .Simple carbohydrates (sugars) are found in soft drinks, candy, fruit, and ice cream.Glucose is the molecule ultimately used by body cells to make ATP.Neurons and RBCs rely almost entirely upon glucose to supply their energy needs.Excess glucose is converted to glycogen or fat and stored .The most abundant dietary lipids, triglycerides, are found in both animal and plant foods.Essential fatty acids – linoleic and linolenic acid, found in most vegetables, must be ingested. Dietary fats help the body to absorb vitamins, a major energy fuel of hepatocytes and skeletal muscle, and a component of myelin sheaths and all cell membranes. Lipids functions in smooth muscle contraction, control of blood pressure and inflammation. Cholesterol stabilizes membranes and is a precursor of bile salts and steroid hormones. The dietary requirements for lipids are higher for infants and children than for adults. The American Heart Association suggests that fats should represent less than 30% of one’s total caloric intake, saturated fats should be limited to 10% or less of one’s total fat intake, and daily cholesterol intake should not exceed 200 mg. Complete proteins that meet all the body’s amino acid needs are found in eggs, milk, milk products, meat, and fish.Incomplete proteins are found in legumes, nuts, seeds, grains, and vegetables. Essential amino acids are the building blocks for nonessential amino acids. Protein supply for nonprotein nitrogen-containing substances. Daily intake should be approximately 0.8g/kg of body weight. All amino acids needed must be present at the same time for protein synthesis to occur. Protein will be used as fuel if there is insufficient carbohydrate or fat available. The rate of protein synthesis equals the rate of breakdown and loss. Anabolic hormones accelerate protein synthesis. Vitamins are organic compounds needed for growth and good health. They are crucial in helping the body use nutrients and often function as coenzymes. Only vitamins D, K, and B are synthesized in the body; all others must be ingested. Water-soluble vitamins (B-complex and C) are absorbed in the gastrointestinal tract . Vitamin B12 additionally requires gastric intrinsic factor to be absorbed. Fat-soluble vitamins (A, D, E, and K) bind to ingested lipids and are absorbed with their digestion products. Vitamins A, C, and E also act in an antioxidant cascade. There are seven minerals are required in moderate amounts . These are calcium, phosphorus, potassium, sulfur, sodium, chloride, and magnesium. Dozens are required in trace amounts. Minerals work with nutrients to ensure proper body functioning. Calcium, phosphorus, and magnesium salts harden bone.