Techniques for Evaluation of Evidences in Forensic Casework

Techniques for Evaluation of Evidences in Forensic Casework Modern Techniques Used For the Evaluation of Evidences Collected In Forensic Casework: A Review Abstract In the modern era, many technological developments have been made in the field of science as well as forensic science which stand powerful and strong to overcome the issues involved in forensic casework. In this review, three emerging techniques have been discussed that proved helpful for the forensic analysis. One of them is Stereo lithography which is being used for prototyping purposes which involves fabrication of three dimensional structures (3D modeling) for this purpose some complex mathematical measurements, biological and chemical informational data is required. At the second number, Ambient mass spectrometry (ambient MS) comes which is also a very emerging and powerful method for the identification of explosives materials even at the nanogram levels, for the analysis of pharmaceutical products (e.g. tablets), authentication of ink and document, identification of biological fluids such as urine and blood plasma and also for the testing of metabolites present in breathâ€℠¢s air. Third most widely used technology for glass fragments analysis is Laser Ablation Inductively Coupled Mass Spectrometry (LA-ICP-MS), even for the trace evidence collected from the criminal site. Keywords: Forensic casework, Prototyping, 3D modeling, Ambient MS, metabolites. Introduction These three powerful techniques are mentioned below: Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS): Glass elements represent a very valuable class of evidence, even in trace amount. Many other materials that present in trace amount, they are simply moved from victim to defendant and ignored very simply by the accused. While in case of broken glass particles, even minor particles can be proved very helpful to find important ways of solving the hurdle like the direction and speed of the bullets and their impact on the glass that is being analyzed(1). LA-ICP-MS is a very sensitive machine that converts the glass materials into very small size, even up to their atomic size.(2) After that the matching is done of the sample that collected from the crime site. Then the similarities are checked and make the statement about the accused person, on the basis of the evaluation of evidence, collected from a crime site. LA-ICP-MS has another application of detection of non-metals and metals, even they are traces at very min or quantity(3). Stereo lithography: Rapid Prototyping technique that uses a laser beam to develop a sharp image of layer by solidifying or hardening of the photopolymer material(4). It develops images and specific 3D models by combining with Computer Aided Designing (CAD) that includes 3D confirmation point exchanging. In this way it helps to create images.(5) (6) For the analysis of different evidences, different operational 3D models are available. One of them is prototyping that is a very popular and accurate model for the manufacturing of images at high levels(7). CAD plans combine with this machine to generate 3D models in layer by layer sequence.(5, 8) Laser sintering and many other imaging processes are available like stereo lithography which involves the flow or movement of photopolymers like a jet in an inkjet apparatus.(9, 10) Ambient mass spectrometry: Ambient MS technology has been under considerations in this study, as it is the very rapidly emerging method for the identification of surface directly regardless any treatment before analyzing(11). This technology is very speedy and gives accurate results and facilitates as it involves no purification and removal of sample for the surface analysis. At Crime site many evidences present and different identification analysis are being done to study the toxicology and chemical residue concentrations. For this purpose desorption electrospray ionization (DESI)(12, 13),direct analysis in real time (DART)(14), plasma assisted desorption ionization (PADI)(15)and extractive electrospray surface ionization (EESI)(16), techniques play their important part. Working Principle of Technologies: LA-ICP-MS: This process is carried out by ICP-MS machine which involves three steps procedure(17), firstly the sample introduction mechanism in which the sample is being installed to the apparatus, and then the generated ions transfer into plasma and interface tube and last step involves the detection by using mass spectrometer detector.(17)MS was firstly built for the liquid sample analysis but now this technology is being used for gaseous as well as solid materials. A decade ago, solution nebulization (SN) mechanism was being used,(2, 3, 18) often for the introduction of sample into the MS machine for forensic analysis but it involved very lengthy and time consuming protocol , so to overcome this issue now a days ,sample introduction is being done by laser ablation (LA)(19-22). To generate ions of the sample, laser beam is used that focused on the analyzing sample .After that generated ions or ablated elements are further passed out to the next chamber, termed as plasma and MS interface region, digestion and ionization processes are being carried out for the sample in it. At the third stage for the isotopic and elemental examination, the generated ions by second chamber are transferred to the mass spectrometer detector. Then MS detector collects the ions and separates them on the basis of their charge to mass ratio and builds an analysis on that base identification of the unknown samples is done. Accordingly, solution nebulization (SN) requires high amount of sample to being analyzed even in milligrams (23-27), while some micrograms of the sample in quantity are just enough for laser ablation (LA) method. The main advantage of using laser ablation (LA) is no risk of contamination and loss of sample. Through a study, it is confirmed that laser ablation required only minimum 0.9 ÃŽ ¼g mass of sample for forensic glass analysis, while for SN system this amount range exceeded up to 500 ÃŽ ¼g to 2000 ÃŽ ¼g. Stereo lithography: Exposure of specific lengths of radioactive rays to the liquid polymer can converted it into the solid phase very quickly in this replication based process.(28) Ultra violet (UV) of very intensity is being fallen on the liquid layer of the photopolymer. By the UV light focusing onto the sample, some chemical changes occur that converts the liquid sample into the solid phase. This process involves the drawing of layers with the use of UV light onto the liquid sample surface(29). The conversion of liquid phase into solid phase is due to polymerization of the sample by UV light. This technique completes its process with the combination of different computer soft wares like CAD and CAE. Different types of liquid photopolymers are currently available that are being utilized for stereo lithography.(5) Many polymers are very strong, can resist in high temperature condition and low moisture situations. Oxygen inhibition is the big short coming that is being faced in prototyping technique by acrylates which are cured by UV rays. With the use of cationic and polymerization,(30) the hybrids are become able to test different types of liquid samples and this test involves the use of UV light. FDA gave approval to use some materials for these purposes are epoxy based material, rubbers and silicon like materials etc. Many other materials like nylon, polycarbonate, ABS and some type of resins are available in the market that can be used in the stereo lithography apparatus. In 1988, this system was developed for the forensic analysis. Ambient mass spectrometry: Cooks and co-researchers developed an ambient desorption method that involves desorption and ionization of sample collected from crime site, with the help of electrospray machine. For the identification of biological samples(31, 32), environmental study(33) and to check the pharmaceuticals products validity(34), in the field of forensics very modified techniques are settled that show accurate results, one of them is DESI as shown in Figure 1.(a)(35-37). For the chemical residues analysis as well as drugs of accused, a new approach was developed alongside the DESI termed as DART by Cody and his partners, although DESI is a very sensitive and accurate method(38). Ionization of particles is done by the ejection of nitrogen and helium light onto the surface in DART method as shown in Figure 1. (b). McCoustra developed a new emerging method that ionizes the material with the use of plasma source, termed as PADI as shown in Figure 1. (c). Zenobi, a scientist settled an instrument known as EESI to ionize the materials or particles with the use of directly inserted gal with full speed into the electro spray region of the mass spectrometry apparatus, in which the desorption of particles is done by the continuous flow of gas and this method helps to analyze the liquids and other solutions(39).   Ã‚   (a) (b) (c) Figure1. Schematics of source: (a) DESI (b) DART (c) PADI Applications in Forensics Forensic glass Analysis: Recently, FBI and other forensics groups have been involved in the usage of LA-ICP-MS as it has major application of analysis of broken glass, collected from a crime site, although this technology requires very big amount to run. Stereo lithography: It has current issues related applications like to study the anatomy of the body shape, it’s very useful in surgeries development (e.g. orthopedic) (5).For the development of prosthetic devices , stereo lithography’s use have been increased quite prominently . MRI data analysis and identification of bone injury produced by trauma have been carried out in recent time by this method. Identification of metabolites from breath: As the breath includes so many types of metabolites through which a lot of information about an accused can be generated. Metabolites can give information about meals and recently use of drug or alcohol by the suspect and it can also recognize the biomarkers(40). Ink analysis and document verification: The identification of inks used in writing of the documents or any other confidential report can prove the authenticity of the document in the law court. Ingredients of ink like organic solvents are separated using liquid chromatography and then further analyzed by mass spectrometry(34, 41). Conclusion In this article, we review the possible potential of different forensic analysis techniques for the evaluation of evidences, collected from criminal site. LA technique shows powerful potential for forensic glass analysis(42). DESI clearly illustrates the identification of biological samples, environmental study and to check the pharmaceuticals products validity(34). Stereo lithographic techniques are more precisely and accurately used for MRI data analysis(5). 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Hunters in the Snow Essay

Friendship. What does it mean? I believe that friendship means that you’re there for a person no matter what and if they are in need then you would do anything to help them out. Hunters in the Snow doesn’t exactly define friendship. If anything it defines betrayal. Throughout this short story some of the characters do actions to their â€Å"friend.† Betrayal and loyalty is kind of the theme throughout the story and it makes a person think about who their real friends are. In Hunters in the Snow, Kenny, Tub, and Frank are all supposed to be friends, but through a couple series of events make a person wonder what exactly friendship means to them. Each one of the characters has certain traits that can lead them to betray them. Towards the end of the story, the reader starts to feel sorry for Kenny after Tub and Frank leave him in the back of the pickup while they go eat pancakes, then Frank and Tub â€Å"accidentally† make a wrong turn so they couldn’t get Kenny to hospital in time after being shot. Lack of loyalty also leads to betrayal in this short story. In the beginning, Tub and Kenny were pretty good friends, but towards the end, Kenny is almost the outcast when Tub and Frank just leave him in the back of the truck wounded while they stop and eat. Betrayal and loyalty is a key characteristic that is portrayed in Hunters in the Snow. After reading this short story it really makes on person think about the characteristics they look for in their friends. Throughout this short story it was pretty obvious that all three of the main characters lack characteristics of being a good friend, but they are all very good at backstabbing their â€Å"friends†.

Fluid, Electrolyte, and Acid-Base Balance: Introduction to Body Fluids Essay

   Fluid Compartments Water occupies two main fluid compartments Intracellular fluid (ICF) – about two thirds by volume, contained in cells Extracellular fluid (ECF) – consists of two major subdivisions Plasma – the fluid portion of the blood Interstitial fluid (IF) – fluid in spaces between cells Other ECF – lymph, cerebrospinal fluid, eye humors, synovial fluid, serous fluid, and gastrointestinal secretions Extracellular and Intracellular Fluids Water is the universal solvent Solutes are broadly classified into: Electrolytes – inorganic salts, all acids and bases, and some proteins Electrolytes determine the chemical and physical reactions of fluids Electrolytes have greater osmotic power than nonelectrolytes Water moves according to osmotic gradients Nonelectrolytes – examples include glucose, lipids, creatinine, and urea Each fluid compartment of the body has a distinctive pattern of electrolytes Extracellular fluids are similar (except for high protein content of plasma) Sodium is the chief cation Chloride is the major anion Intracellular fluids have low sodium and chloride Potassium is the chief cation Phosphate is the chief anion Proteins, phospholipids, cholesterol, and neutral fats account for: 90% of the mass of solutes in plasma 60% of the mass of solutes in interstitial fluid 97% of the mass of solutes in the intracellular compartment Fluid Movement Among Compartments Compartmental exchange is regulated by osmotic and hydrostatic pressures Net leakage of fluid from the blood is picked up by lymphatic vessels and returned to the bloodstream Exchanges between interstitial and intracellular fluids are complex due to the selective permeability of the cellular membranes Two-way water flow is substantial Ion fluxes are restricted and move selectively by active transport Nutrients, respiratory gases, and wastes move unidirectionally Plasma is the only fluid that circulates throughout the body and links external and internal environments Osmolalities of all body fluids are equal; changes in solute concentrations are quickly followed by osmotic changes Water Balance and ECF Osmolality To remain properly hydrated, water intake must equal water output Water intake sources Ingested fluid (60%) and solid food (30%) Metabolic water or water of oxidation (10%) Water output Urine (60%) and feces (4%) Insensible losses (28%), sweat (8%) Increases in plasma osmolality trigger thirst and release of antidiuretic hormone (ADH) Regulation of Water – Homeostaisis Intake – Hypothalmic Thirst Center Thirst is quenched as soon as we begin to drink water Feedback signals that inhibit the thirst centers include: Moistening of the mucosa of the mouth and throat Activation of stomach and intestinal stretch receptors Influence and Regulation of ADH Water reabsorption in collecting ducts is proportional to ADH release Low ADH levels produce dilute urine and reduced volume of body fluids High ADH levels produce concentrated urine Hypothalamic osmoreceptors trigger or inhibit ADH release Factors that specifically trigger ADH release include prolonged fever; excessive sweating, vomiting, or diarrhea; severe blood loss; and traumatic burns Disorders of Water Balance: Dehydration Water loss exceeds water intake and the body is in negative fluid balance Causes include: hemorrhage, severe burns, prolonged vomiting or diarrhea, profuse sweating, water deprivation, and diuretic abuse Signs and symptoms: cottonmouth, thirst, dry flushed skin, and oliguria Prolonged dehydration may lead to weight loss, fever, mental confusion Other consequences include hypovolemic shock and loss of electrolytes Hypotonic Hydration Renal insufficiency or an extraordinary amount of water ingested quickly can lead to cellular overhydration, or water intoxication ECF is diluted – sodium content is normal but excess water is present The resulting hyponatremia promotes net osmosis into tissue cells, causing swelling These events must be quickly reversed to prevent severe metabolic disturbances, particularly in neurons Edema. Atypical accumulation of fluid in the interstitial space, leading to tissue swelling Caused by anything that increases flow of fluids out of the bloodstream or hinders their return. Factors that accelerate fluid loss  include: Increased blood pressure, capillary permeability Incompetent venous valves, localized blood vessel blockage Congestive heart failure, hypertension, high blood volume Hindered fluid return usually reflects an imbalance in colloid osmotic pressures Hypoproteinemia – low levels of plasma proteins Forces fluids out of capillary beds at the arterial ends Fluids fail to return at the venous ends Results from protein malnutrition, liver disease, or glomerulonephritis Blocked (or surgically removed) lymph vessels: Cause leaked proteins to accumulate in interstitial fluid Exert increasing colloid osmotic pressure, which draws fluid from the blood Interstitial fluid accumulation results in low blood pressure and severely impaired circulation Sodium in Fluid and Electrolyte Balance Sodium holds a central position in fluid and electrolyte balance Sodium salts: Account for 90-95% of all solutes in the ECF Contribute 280 mOsm of the total 300 mOsm ECF solute concentration Sodium is the single most abundant cation in the ECF Sodium is the only cation exerting significant osmotic pressure The role of sodium in controlling ECF volume and water distribution in the body is a result of: Sodium being the only cation to exert significant osmotic pressure Sodium ions leaking into cells and being pumped out against their electrochemical gradient Sodium concentration in the ECF normally remains stable Changes in plasma sodium levels affect: Plasma volume, blood pressure ICF and interstitial fluid volumes Renal acid-base control mechanisms are coupled to sodium ion transport Regulation of Sodium Balance: Aldosterone The renin-angiotensin mechanism triggers the release of aldosterone This is mediated by juxtaglomerular apparatus, which releases renin in response to: Sympathetic nervous system stimulation Decreased filtrate osmolality Decreased stretch due to decreased blood pressure Renin catalyzes the production of angiotensin II, which prompts aldosterone release Adrenal cortical cells are directly stimulated to release aldosterone by elevated K+ levels in the ECF Aldosterone brings about its effects (diminished urine output and increased blood volume) slowly Cardiovascular System Baroreceptors Baroreceptors alert the brain of increases in blood volume (hence increased blood pressure) Sympathetic nervous system impulses to the kidneys decline Afferent arterioles dilate Glomerular filtration rate rises Sodium and water output increase This phenomenon, called pressure diuresis, decreases blood pressure Drops in systemic blood pressure lead to opposite actions and systemic blood pressure increases Since sodium ion concentration determines fluid volume, baroreceptors can be viewed as â€Å"sodium receptors† Atrial Natriuretic Peptide (ANP) Reduces blood pressure and blood volume by inhibiting: Events that promote vasoconstriction Na+ and water retention Is released in the heart atria as a response to stretch (elevated blood pressure) Has potent diuretic and natriuretic effects Promotes excretion of sodium and water Inhibits angiotensin II production Influence of Other Hormones on Sodium Balance Estrogens: Enhance NaCl reabsorption by renal tubules May cause water retention during menstrual cycles Are responsible for edema during pregnancy Progesterone: Decreases sodium reabsorption Acts as a diuretic, promoting sodium and water loss Glucocorticoids – enhance reabsorption of sodium and promote edema Regulation of Potassium Balance Relative ICF-ECF potassium ion concentration affects a cell’s resting membrane potential Excessive ECF potassium decreases membrane potential Too little K+ causes hyperpolarization and nonresponsiveness Hyperkalemia and hypokalemia can: Disrupt electrical conduction in the heart Lead to sudden death Hydrogen ions shift in and out of cells Leads to corresponding shifts in potassium in the opposite direction Interferes with activity of excitable cells Influence of Aldosterone Aldosterone stimulates potassium ion secretion by principal cells In cortical collecting ducts, for each Na+ reabsorbed, a K+ is secreted Increased K+ in the ECF around the adrenal cortex causes: Release of aldosterone –>Potassium secretion Potassium controls its own ECF concentration via feedback regulation of aldosterone release Regulation of Calcium Ionic calcium in ECF is important for: Blood clotting Cell membrane permeability Secretory behavior Hypocalcemia: Increases excitability, causes muscle tetany Hypercalcemia: inhibits neurons and muscle cells; cause heart arrhythmias Calcium balance is controlled by parathyroid hormone and calcitonin PTH promotes increase in calcium levels by targeting: Bones – PTH activates osteoclasts to break down bone matrix Small intestine – PTH enhances intestinal absorption of calcium Kidneys – PTH enhances calcium reabsorption and decreases phosphate reabsorption Calcium reabsorption and phosphate excretion go hand in hand Influence of Calcitonin Released in response to rising blood calcium levels Calcitonin is a PTH antagonist, but its contribution to calcium and phosphate homeostasis is minor to negligible Acid Base Balance Introduction to Acids and Bases Strong acids – all their H+ is dissociated completely in water Weak acids – dissociate partially in water and are efficient at preventing pH changes Strong bases – dissociate easily in water and quickly tie up H+ Weak bases – accept H+ more slowly (e.g., HCO3 ¯ and NH3) Normal pH of body fluids Arterial blood is 7.4 Venous blood and interstitial fluid is 7.35 Intracellular fluid is 7.0 Alkalosis or alkalemia – arterial blood pH rises above 7.45 Acidosis or acidemia – arterial pH drops below 7.35 (physiological acidosis) Sources of Hydrogen Ions – Most hydrogen ions originate from cellular metabolism Breakdown of phosphorus-containing proteins releases phosphoric acid into the ECF Anaerobic respiration of glucose produces lactic acid Fat metabolism yields organic acids and ketone bodies Transporting carbon dioxide as bicarbonate releases hydrogen ions Hydrogen Ion Regulation Concentration of hydrogen ions is regulated sequentially by: Chemical buffer systems – act within seconds Physiological buffer systems The respiratory center in the brain stem – acts within 1-3 minutes Renal mechanisms – require hours to days to effect pH changes Chemical Buffer Systems Bicarbonate Buffer System A mixture of carbonic acid (H2CO3) and its salt, sodium bicarbonate (NaHCO3) (potassium or magnesium bicarbonates work as well) If strong acid is added: Hydrogen ions released combine with the bicarbonate ions and form carbonic acid (a weak acid) The pH of the solution decreases only slightly If strong base is added: It reacts with the carbonic acid to form sodium bicarbonate (a weak base) The pH of the solution rises only slightly This system is the only important ECF buffer Phosphate Buffer System Nearly identical to the bicarbonate system Its components are: Sodium salts of dihydrogen phosphate (H2PO4 ¯), a weak acid Monohydrogen phosphate (HPO42 ¯), a weak base This system is an effective buffer in urine and intracellular fluid Protein Buffer System Plasma and intracellular proteins are the body’s most plentiful and powerful buffers Some amino acids of proteins have: Free organic acid groups (weak acids) Groups that act as weak bases (e.g., amino groups) Amphoteric molecules are protein molecules that can function as both a weak acid and a weak base Physiological Buffer Systems Respiratory Buffer System The respiratory system regulation of acid-base balance is a physiological buffering system There is a reversible equilibrium between: Dissolved carbon dioxide and water Carbonic acid and the hydrogen and bicarbonate ions CO2 + H2O –> H2CO3 –> H+ + HCO3 ¯ During carbon dioxide unloading, hydrogen ions are incorporated into water When hypercapnia or rising plasma H+ occurs: Deeper and more rapid breathing expels more carbon dioxide Hydrogen ion concentration is reduced Alkalosis causes slower, more shallow breathing, causing H+ to increase Respiratory system impairment causes acid-base imbalance (respiratory acidosis or respiratory alkalosis) Renal Mechanisms of Acid-Base Balance Introduction Chemical buffers can tie up excess acids or bases, but they cannot eliminate them from the body The lungs can eliminate carbonic acid by eliminating carbon dioxide Only the kidneys can rid the body of metabolic acids (phosphoric, uric, and lactic acids and ketones) and prevent metabolic acidosis The ultimate acid-base regulatory organs are the kidneys The most important renal mechanisms for regulating acid-base balance are: Conserving (reabsorbing) or generating new bicarbonate ions Excreting bicarbonate ions Losing a bicarbonate ion is the same as gaining a hydrogen ion; reabsorbing a bicarbonate ion is the same as losing a hydrogen ion Hydrogen ion secretion occurs in the PCT Hydrogen ions come from the dissociation of carbonic acid Reabsorption of Bicarbonate CO2 combines with water in tubule cells, forming H2CO3 H2CO3 splits into H+ and HCO3- For each H+ secreted, a Na+ and a HCO3- are reabsorbed by the PCT cells Secreted H+ form H2CO3; thus, HCO3- disappears from filtrate at the same rate that it enters the peritubular capillary blood H2CO3 formed in filtrate dissociates to release CO2 + H2 CO2 then diffuses into tubule cells, where it acts to trigger further H+ secretion Hydrogen Ion Excretion Dietary H+ must be counteracted by generating new HCO3- The excreted H+ must bind to buffers in the urine (phosphate buffer system) Intercalated cells actively secrete H+ into urine, which is buffered and excreted HCO3- generated is: Moved into the interstitial space via a cotransport system Passively moved into the peritubular capillary blood In response to acidosis: Kidneys generate HCO3-and add them to the blood An equal amount of H+ are added to the urine Ammonium Ion (NH4+) Excretion This method uses NH4+ produced by the metabolism of glutamine in PCT cells Each glutamine metabolized produces two ammonium ions and two bicarbonate ions HCO3- moves to the blood and ammonium ions are excreted in urine Respiratory Acidosis and Alkalosis Result from failure of the respiratory system to balance pH PCO2 is the single most important indicator of respiratory inadequacy PCO2 levels – normal PCO2 fluctuates between 35 and 45 mm Hg Values above 45 mm Hg signal respiratory acidosis Values below 35 mm Hg indicate respiratory alkalosis Respiratory acidosis is the most common cause of acid-base imbalance Occurs when a person breathes shallowly, or gas exchange is hampered by diseases such as pneumonia, cystic fibrosis, or emphysema Respiratory alkalosis is a common result of hyperventilation Metabolic Acidosis All pH imbalances except those caused by abnormal blood carbon dioxide levels Metabolic acid-base imbalance – bicarbonate ion levels above or below normal (22-26 mEq/L) Metabolic acidosis is second most common cause of acid-base imbalance Typical causes are ingestion of too much alcohol and excessive loss of bicarbonate ions Other causes include accumulation of lactic acid, shock, ketosis in diabetic crisis, starvation, and kidney failure Metabolic Alkalosis Rising blood pH and bicarbonate levels indicate metabolic alkalosis Typical causes are: Vomiting of the acid contents of the stomach Intake of excess base (e.g., from antacids) Constipation, in which excessive bicarbonate is reabsorbed Respiratory and Renal Compensations Acid-base imbalance due to inadequacy of a physiological buffer system is compensated for by the other system The respiratory system will attempt to correct metabolic acid-base imbalances The kidneys will work to correct imbalances caused by respiratory disease Respiratory Compenstaion In metabolic acidosis: The rate and depth of breathing are elevated Blood pH is below 7.35 and bicarbonate level is low As carbon dioxide is eliminated by the respiratory system, PCO2 falls below normal In metabolic alkalosis: Compensation exhibits slow, shallow breathing, allowing carbon dioxide to accumulate in the blood Correction is revealed by: High pH (over 7.45) and elevated bicarbonate ion levels RisingPCO2 Renal Compensation To correct respiratory acid-base imbalance, renal mechanisms are stepped up Acidosis has high PCO2 and high bicarbonate levels The high PCO2 s the cause of acidosis The high bicarbonate levels indicate the kidneys are retaining bicarbonate to offset the acidosis Alkalosis has Low PCO2 and high pH The kidneys eliminate bicarbonate from the body by failing to reclaim it or by actively secreting it

10 Facts Worth Knowing About Noah Webster

Born in West Hartford, Connecticut on October 16, 1758, Noah Webster is best known today for his magnum opus, An American Dictionary of the English Language (1828). But as David Micklethwait reveals in Noah Webster and the American Dictionary (McFarland, 2005), lexicography wasnt Websters only great passion, and the dictionary wasnt even his best-selling book. By way of introduction, here are 10 facts worth knowing about the great American lexicographer Noah Webster. During his first career as a schoolteacher at the time of the American Revolution, Webster was concerned that most of his students textbooks came from England. So in 1783 he published his own American text, A Grammatical Institute of the English Language. The â€Å"Blue-Backed Speller,† as it was popularly known, went on to sell nearly 100 million copies over the next century.Webster subscribed to the biblical account of the origin of language, believing that all languages derived from Chaldee, an Aramaic dialect.Though he fought for a strong federal government, Webster opposed plans to include a Bill of Rights in the Constitution. Liberty is never secured with such paper declarations, he wrote, nor lost for want of them.Even though he himself borrowed shamelessly from Thomas Dilworths New Guide to the English Tongue (1740) and Samuel Johnsons Dictionary of the English Language (1755), Webster fought vigorously to protect his own work from plagiarists. His efforts led to the c reation of the first federal copyright laws in 1790.In 1793 he founded one of New York Citys first daily newspapers, American Minerva, which he edited for four years.Websters Compendious Dictionary of the English Language (1806), a forerunner of An American Dictionary, sparked a war of the dictionaries with rival lexicographer Joseph Worcester. But Worcesters Comprehensive Pronouncing and Explanatory English Dictionary didnt stand a chance. Websters work, with 5,000 words not included in British dictionaries and with definitions based on the usage of American writers, soon became the recognized authority.In 1810, he published a booklet on global warming titled â€Å"Are Our Winters Getting Warmer?†Although Webster is credited for introducing such distinctive American spellings as color, humor, and center (for British colour, humour, and centre), many of his innovative spellings (including masheen for machine and yung for young) failed to catch on. See Noah Websters Plan to Re form English Spelling.Webster was one of the principal founders of Amherst College in Massachusetts.In 1833 he published his own edition of the Bible, updating the vocabulary of the King James Version and cleansing it of any words that he thought might be considered offensive, especially for females. In 1966, Websters restored birthplace and childhood home in West Hartford was reopened as a museum, which you can visit online at the Noah Webster House West Hartford Historical Society. After the tour, you may feel inspired to browse through the original edition of Websters American Dictionary of the English Language.