Silver Facts (Atomic Number 47 and Element Symbol Ag)

Silver Facts (Atomic Number 47 and Element Symbol Ag) Silver is a transition metal with element symbol Ag and atomic number 47. The element is found in jewelry and currency for its beauty and value and in electronics for its high conductivity and malleability. Silver  Basic Facts Atomic Number: 47 Symbol: Ag Atomic Weight: 107.8682 Discovery: Known since prehistoric time. Man learned to separate silver from lead as early as 3000 B.C. Electron Configuration: [Kr]5s14d10 Word Origin: Anglo-Saxon Seolfor or siolfur; meaning silver, and Latin argentum meaning silver Properties: The melting point of silver is 961.93 °C, boiling point is 2212 °C, specific gravity is 10.50 (20 °C), with a valence of 1 or 2. Pure silver has a brilliant white metallic luster. Silver is slightly harder than gold. It is very ductile and malleable, exceeded in these properties by gold and palladium. Pure silver has the highest electrical and thermal conductivity of all metals. Silver possesses the lowest contact resistance of all metals. Silver is stable in pure air and water, although it tarnishes upon exposure to ozone, hydrogen sulfide, or air containing sulfur. Uses: The alloys of silver have many commercial uses. Sterling silver (92.5% silver, with copper or other metals) is used for silverware and jewelry. Silver is used in photography, dental compounds, solder, brazing, electrical contacts, batteries, mirrors, and printed circuits. Freshly deposited silver is is the best known reflector of visible light, but it rapidly tarnishes and loses its reflectance. Silver fulminate (Ag2C2N2O2) is a powerful explosive. Silver iodide is used in cloud seeding to produce rain. Silver chloride can be made transparent and is also used as a cement for glass. Silver nitrate, or lunar caustic, is used extensively in photography. Although silver itself is not considered toxic, most of its salts are poisonous, due to the anions involved. Exposure to silver (metal and soluble compounds) should not exceed 0.01 mg/M3 (8 hour time-weighted average for a 40 hour week). Silver compounds can be absorbed into the circulatory system, with deposition of reduced silver in body tissues. This may result in argyria, which is characterized by a greyish pigmentation of the skin and mucous membranes. Silver is germicidal and may be used to kill many lower organisms without harm to higher organisms. Silver is used as coinage in many countries. Sources: Silver occurs native and in ores incuding argentite (Ag2S) and horn silver (AgCl). Lead, lead-zinc, copper, copper-nickel, and gold ores are other prinicipal sources of silver. Commercial fine silver is at least 99.9% pure. Commercial purities of 99.999% are available. Element Classification: Transition Metal Silver Physical Data Density (g/cc): 10.5 Appearance: silvery, ductile, malleable metal Isotopes: There are 38 known isotopes of silver ranging from Ag-93 to Ag-130. Silver has two stable isotopes: Ag-107 (51.84% abundance) and Ag-109 (48.16% abundance). Atomic Radius (pm): 144 Atomic Volume (cc/mol): 10.3 Covalent Radius (pm): 134 Ionic Radius: 89 (2e) 126 (1e) Specific Heat (20 °C J/g mol): 0.237 Fusion Heat (kJ/mol): 11.95 Evaporation Heat (kJ/mol): 254.1 Debye Temperature (K): 215.00 Pauling Negativity Number: 1.93 First Ionizing Energy (kJ/mol): 730.5 Thermal Conductivity: 429 W/m ·K 300 K Oxidation States: 1 (most common), 2 (less common), 3 (less common) Lattice Structure: Face-Centered Cubic Lattice Constant (Ã…): 4.090 CAS Registry Number: 7440-22-4 Silver Trivia: Silvers element symbol Ag, is from the Latin word argentum meaning silver.In many cultures, and some alchemical texts, silver was associated with the Moon while gold was associated with the Sun.Silver has the highest electrical conductivity of all metals.Silver has the highest thermal conductivity of all metals.Silver halide crystals darken when exposed to light. This process was vital to photography.Silver is considered one of the noble metals.Silver is slightly harder (less malleable) than gold.Silver ions and silver compounds are toxic to many types of bacteria, algae and fungi. Silver coins used to be stored in containers of water and wine to prevent spoiling.Silver nitrate has been used to prevent infection in burns and other wounds. More Silver Facts Sources Emsley, John (2011). Natures building blocks: An A-Z Guide to the Elements. Oxford University Press. pp. 492–98. ISBN 978-0-19-960563-7.Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.Hammond, C. R. (2004). The Elements, in Handbook of Chemistry and Physics (81st ed.). CRC press. ISBN 978-0-8493-0485-9.Weast, Robert (1984). CRC, Handbook of Chemistry and Physics. Boca Raton, Florida: Chemical Rubber Company Publishing. pp. E110. ISBN 0-8493-0464-4.

Whos Tooth is it Anyway

Response to: Whos Tooth is it Anyway? Julie Kazimiroff, dental professor at NYU College of Dentistry, attempts to cover the issue of cusp patterns with respect to relatedness among the hominoids. She starts off by posing a question regarding the 5 cusp (Y-5) molar pattern present in extant primates. To begin with, she emphasizes the importance of teeth to phylogenetics, as they are often times all that survives from an organism. DNA is brought into the paper to explain how testing techniques have been utilized to enhance the answering of relatedness questions, particularly in terms of chimps, apes and humans. In her title she mentions Dryopithecus, an early dental ape thought to be an early hominoid. Dryopithecus possessed the Y-5 cusp pattern found among the extant primates, and this paper seems to indicate that it actually may be the origination of such a pattern in terms of the beginning of the hominoid lineages. In tracking an answer to the question posed, it appears that it lies in the study of mammalian molarization. It was here that a pattern emerged which seemed to define what was characteristic of primates, the Dryopithecus pattern, that of the Y-5 cusp pattern. In tracing the pattern, it was determined that it could be found in not only extant groups of primates, but in extinct groups such as those ancestral to the great apes and gibbons also. By combining the fossil evidence provided by the molar pattern data with the molecular data, it was determined that the gibbons was the earliest branch of the Hominoidea, and all primates are related through this pattern. The article goes beyond primates in addressing the question however, as reference to reptiles and the idea that their triangular molars ( 3 cusps) are considered to be principle cusps that have evolved over time as mammals began to emerge, carrying and modifying the cusps and patterns according to species divergences in

Drupal Open Source Research Paper Example | Topics and Well Written Essays - 2250 words

Drupal Open Source - Research Paper Example This paper explores the component and contribution to the root concept. High-level vision An Application where developers are able easily to organize, manage and publish their content, with an endless variety of customization. Basic Rationale Availability of Apache Solr integration module. The taxonomy concepts are easily hooked onto Apache Solr for filtering based on meta-information, such as tags, authors, publications, etc. in Drupal, an author can be part of a taxonomy and user profiles can be made for these authors - by default ability to write Themes using PHP Template, instead of depending upon Typo script Ability to handle a large quantity (over 1000) of diverse sites Central management tools Integration with Active Directory Stakeholder group In general, man, woman, students, working people. Computer programmers Starting assumption Improvements and re-designing will be done from the existing versions to a more stable and user-friendly application. Field Study Guides extracte d from the user's e-mail forums 1. How many people use Drupal? Why? 2. How many sites have been created using Drupal? 3. How often is Drupal used? 4. Which difficulties are encounter during usage?  5.  What do users like most about Drupal? 6. Is Drupal a viable solution for the user’s website? Does it have any limited functionality? 7. Do users encounter problems when Installing Drupal? Which are they? 8. What are the most important features Drupal has? 9. Is there anything that users do not like about Drupal? If so, what are they? 10. Under what conditions users don’t like Drupal and why? Examples. 11. What are the additional features Drupal does not have but users consider important and can improve the situations? Field data collection(answers to the Field Study Guides extracted from the user's e-mail forums) 1. What is the function of Drupal and why do users choose to use Drupal? Drupal is used to create websites. It is used because of Advanced URL Control, Cust om Content Types, and Views, Revision Control, User Management, Excellent Documentation, Large and Friendly Community 2. How many sites have been created using Drupal? Drupal has been used to create several very important website which includes; The United, Nations, Warner Brothers Records, The Discovery Channel, Forbes, The Grateful Dead, AOL, Yahoo, Lime.com, The New York Observer, The Onion, Aaron Wall's SEObook.com 3. How often is Drupal used? Drupal is used often in the creation of the website. 4. Which difficulties are encounter during the usage? There are several problems that are encountered as during the use of Drupal application. They include obscure terminologies, lack of realistic previews, limited functionalities. Among others What do users like most about Drupal? Because of: well interaction of plug-in with its core, it is secure, Drupal can do blogging 5. Is Drupal a viable solution for the user’s website? Does it have any limited functionality? Yes, although i t has some limited functionality 6. Do users encounter problems when Installing Drupal? Which are they? Yes, uninstalling modules fails; whenever a user attempts to install Drupal he gets this "Table variable already exists" 7. What are the most important features Drupal has? Flexibility, Good Governance, Contributed Code, Large Vendor Pool, Scalability  

Its midterm exam Essay Example | Topics and Well Written Essays - 750 words

Its midterm exam - Essay Example rthless if both the responsibility and authority are not equal to each other as the person may not be able to complete his responsibility as he did not have enough authority to obtain resources. 6. When a manager’s span of control is wide, he has a lot of subordinates reporting to him as compared to managers who have a narrow span of control. In such cases a manager may experience loss of control. 7. Empowerment of employees leads to increased employee engagement in the decision making process and this allows employees to bring in new ideas; this even motivates the employees as they gain a sense of responsibility. Empowerment may be viewed in a negative manner by employees as they may think that manager is just offloading his burden on their shoulders. 9. Exploitative Authoritative and Benevolent Authoritative System are two close approaches of management that are similar to theory Y as these two approaches states that decisions are made at the top and delegated to the lower section of an organization. 14. The theory of Fredrick Taylor fails to attain the goal of long term productivity as this theory is based on top down management rule where the instructions are obtained from the top and in such management scenario change is very hard to take place. 15. Delegation of authority takes place when a manager assigns his responsibility and authority to a subordinate to carry out a particular responsibility (Goetsch 120). The advantage obtained from this is that it increases employee’s involvement, but the downside is that the manager is held responsible if the subordinate fails to carry out the responsibility. 18. Electronic communication decrease the lapse time that used to be caused to make appointments and one particular message can be sent to several individuals at the same time. Electronic communication lacks face to face contact, it can lead to misinterpretation of information and electronic communication even contains lack of privacy. 21. It is

Respiratory Distress in Newborn Essay Example for Free

Respiratory Distress in Newborn Essay Respiratory problem are often the case in newborns. It accounts for nearly half of neonatal deaths. Research by Kumar Bhat (1996, p. 93) states that Respiratory Depression (RD) is a common neonatal problem that generally occurs in preterm infants due to surfactant deficiency which relates to antenatal history of immature lung development and term infants of diabetic mothers. To describe some of the common diagnosis associated with RD are: Transient Tachypnea of the newborn (TTNB) was found to be common in both term and preterm babies. Hyaline membrane disease (HMD) was common among pre terms, and meconium aspiration syndrome (MAS) among term and post-term babies. Fatality for RD was found to be 19%, being highest for HMD (57. 1%), followed by MAS (21. 8%) and infection (15. 6%). Therefore, it is crucial to recognise the signs of RD and ensure prompt treatment is rendered to minimize mortality and mobility in newborns at the delivery wards. Accurate physical assessment is done on the newborn on the first and fifth minute at birth to determine if the newborn is getting enough oxygen. By administering APGAR scoring based on each of the components that are assessed in the APGAR scoring are : Cardiovascular (heart rate, color of the skin), fetal respiratory (quality of breathing and neuromuscular function (tone and reflexes based on fetal tone and response to external stimuli). According to Apgar cited in Letko(1996, p. 299) the leading concerns was the ability to rapidly identify newborns requiring resuscitative measures in improving the prognosis. It is done to prevent respiratory depressed newborns from being incorrectly assessed, while minimizing delivery of oxygen and other unnecessary treatment to healthy newborns. Giacoia stated in Letko (1996, p. 300) indicates that a low APGAR score implies an abnormal condition in the newborn, but it does not suggest a specific etiology. Hypotonia in newborn with neuromuscular disorder, for example, may be mistakenly diagnosed to be the cause of birth asphyxia when the newborn is unable to establish or maintain breathing. Maternal sedation and analgesia likewise may decrease tone and responsiveness, resulting in lower score. Managanaro (1994, p. 99) added that infants with 1-min APGAR score was influenced by the mode of delivery and by gestational age rather than asphyxia. Instead, 5-min APGAR score had a high correlation with metabolic acidemia. Infants with low APGAR scores, presented with metabolic acidemia and arterial desaturation have the highest occurance of neonatal intensive care unit . admission and poor neonatal outcome. Therefore, study suggests that the 5-min APGAR score is necessary for immediate assessment and care of the neonate. Scoring APGAR is subjective in terms of interpretation and may lead to biasness. Therefore to correct this deficit, midwives are scoring APGAR at 1 and 5 minute intervals as recommended by Apgar supported in Letko( 1996, p. 00). Letko (1996, p. 302) furthermore, points out by determining oxygenation status by observing cyanosis is an inaccurate method. The manipulating factor consists of the examiner’s skill, adequate lighting, newborn’s skin condition, peripheral perfusion, and hemoglobin level. Physiological changes in the newborn such as functional closure of ductus arteriosus, ductus venosus, and foramen ovale may cause the newborn looking cyanosed. Midwives’ ability to differentiate central and peripheral cyanosis is critical for initiating treatment. Letko (1996, p. 02) explains when present throughout the body, including the mucous membranes and tongue, this condition is termed central cyanosis. When limited to the extremities, it is termed peripheral cyanosis or acrocyanosis. In comparison, central cyanosis refers to central cyanosis is more detrimental as it can result in range of disorder in areas such as cardiac, metabolic and neurological disorders. Newborns may require supplemental oxygen therapy to correct cyanosis. To decrease the subjectivity of the color changes, new technologies, such as pulse oximetry, can be employed with APGAR scoring. Research conducted by House. et. al (1987, p. 96) with regards to the examination of oxygen saturation of neonates in delivery room via the use of pulse oximetry is applicable in my current setting. It states that oxygen saturation did not differ significantly whether by vaginally or by ceaserean section or the presence of any or type of anaesthesia administered. They then concluded that pulse oxygen saturation values are highly accurate and useful in objective judging the adequacy of resuscitative efforts and identifying arterial desaturation during early neonatal period. Alternative methods of assessing oxygenation in neonates, consists of evaluation of cord gas status. Blood gas values are significant for determining oxygenation levels in ill newborns. There are challenges faced in aspects such as blood sampling posed by fast changing bodily processes, difficult assess to arterial sites coupled with small blood volumes and mixed venous samples. Clinicians must consider the importance of associating cord gas results with history taking (maternal history), physical assessments findings and laboratory indices in order to have a comprehensive picture and formulate therapeutic decisions. Brouillette and Waxman (1997, p. 215) suggests when obtaining cord gas samples, arterial blood gas measurements were preferred and taken as the gold standard compared to capillary measurements. Arguments cited in Huch, Huch and Rooth (1994, p. 168. ) against capillary blood sampling include: The skills of the operator, the presenting part of the fetus and membranes must be ruptured. However, it is argued that the merits of sampling capillary blood via fetal scalp sampling for analysis of blood gases are that it is technically easier due to easy access to sites and less likely to result in serious complications than arterial puncture. Therefore, it is a clinically useful method only if the blood gas samples obtained are a sufficiently accurate for arterial measurements. Adapted from Brouillette and Waxman (1997 p. 219), pH values more than 7. 2 are considered reassuring and below 7. 2 suggest immediate neonatal attention is necessary. To ensure accurate results in cord gas samples, the following aspects should be carried out in clinical practice. These include applying good sterile techniques to the site of arterial assess and prevent hemodilution. Also when interpreting results, the midwife must consider different diagnosis that will affect acid- base balance in newborns. Eg. Pulmonary hypertension. Scopes and Ahmad (1966, p. 25) suggests that by monitoring rectal temperature can be used as an indicator to oxygen requirements. Inadequate oxygenation will lead to decrease in deep body temperature. Correcting hypoxia by increasing oxygen consumption will increase deep body temperature. In practice, it is important to maintain the temperature of the labor room to be constant 21-25 degrees and baby’s body and head should be dried immediately after birth to minimize heat loss by evaporation since newborns have poor ability to retain eat (due to their increase skin surface area) which resulted in hypoxia. Aspiration of meconium distinctively occurs after an event of fetal hypoxic stress which leads to intestinal peristalsis, meconium contamination of the amniotic fluid, and gasping respirations that could draw the harmful meconium-stained liqour deep into the fetal lung. All of these would result in white patches observed in chest X-ray. Reflecting on the current practice, after delivery of the fetal head suction is administered to the oropharynx and nasopharynx to remove meconium in the oral and nasal cavities. Initial treatment following delivery, endotracheal suctioning is carried out to remove any remaining meconium-stained amniotic fluid. Improvement in nursing care as cited in Shorten (1989, p. 167) can be made to minimize negative effects throughout the suctioning procedure includes: length of time away from the oxygen source, both the duration and magnitude of applied suction, the ratio of diameters of suction catheter to endotracheal tube, depth of catheter insertion and the amount the infant is handled throughout the procedure. Strategies to improve methods of maintaining airway and minimise negative effects during suctioning include: preoxygenation with hyperventilation or continuous insufflation of oxygen, limiting the depth of catheter insertion to just beyond the distal end of the endotracheal tube, use of sedation and minimise infant handling. Placing basic resuscitation skills and equipment in the hands of midwives would significantly reduce early newborn deaths . A complete neonatal assessment, midwives should include a detailed history (maternal history). Assessment of family history reveals the presence of inheritable congenital defects on the onset and duration of respiratory symptoms, providing clues for early detection and treatment. Such as TTNB begins early and improves with time. Conversely, sepsis and pneumonia may have no early signs but may develop hours to days later. A proper evaluation is crucial as it allows anticipation of any disease that may cause impairment in oxygenation of neonates. Antepartum infection status is important, with regards to assessment on the duration of rupture, color of amniotic fluid . If Group B streptococcous colonisation is present after rupture of membranes, antibiotics can be administered as prophylaxis Additional skills that a midwife should include to effectively assess oxygenation are: applying skills of cardiac auscultation, it detects murmurs indicative of congenital heart anomalies and allows for early intervention to resolve respiratory depression before it worsens. Adding on to assessment using lung auscultation skills may show asymmetrical chest movement in pneumothorax or crackles in pneumonia, or it can be completely clear in transient tachypnea or persistent pulmonary hypertension of the newborn. General assessment of physical examination, midwives are prudent to look for apnea, tachypnea, grunting, stridor, retraction, nasal flaring and using hands to feel for equal lung expansion to identify signs of RD in neonates. Regular monitoring of vital signs such as maternal temperature, maternal tachycardia, and fetal heart status are essential to identify and arrest meconium aspiration and chorioamnionitis Training programmes are developed to reinforce skills which includes; evidence-based action plans with pictorial algorithm through problem-based scenarios in curriculum to facilitate better understanding and learning. Additional courses can also be conducted to correct any knowledge deficits such as: refresher courses, regular neonatal ‘mock’ scenarios to keep midwives updated of current procedures and aid revision of neonatal resuscitation protocols. To ensure prompt action, better communication pathways can be put in place to reinforce the urgency of NICU staff on the need to attend a delivery by the midwives. Which includes: where, when, urgency, indication and gestational age. (â€Å"Neonatal Resuscitation Reviewing the Past to Improve the Future†, 2001). Hermansen and Lorah (2007, p. 990) suggests treatment for neonatal respiratory distress can be both generalized and disease-specific. As Carr (2011) highlighted that midwives should be updated of current neonatal resuscitation protocols. Simple skills like tactile stimulation could save the majority of babies that require help to breathe at the time of birth. Neonates who require oxygen can be enhanced with supplemental oxygen, nasal cannula, or mechanical ventilation in severe cases. Endogenous surfactant administration may be necessary. Antibiotics are administered if bacterial infection is suspected. In conclusion, midwives are in unique position to render lifesaving care to newborns. They can do so by incorporating their skills in doing general assessment first hand to spot RD. Then, applying proper treatment to correct poor oxygenation levels so that to increase the survival of the newborn. Midwives constantly seek to increase their knowledge to improve their skills by demonstrating evidence- based practice in their daily care.

Organizational Psychology :: Graduate Admissions Essays

Organizational Psychology I worked throughout high school and college. Consequently, I know the frustration of squandered effort, perceived inequities in reward systems, and lack of job satisfaction. I also know the triumph of excellent performance, intrinsic job satisfaction, and the piece of mind that accompanies work well designed. The ultimate goal of Industrial/Organizational Psychology is to reduce the margin that exists between how people could feel about their work, and how people do feel about their work; while integrating the organization's and the individual's needs. Because of my varied work experience, I am able to offer strength and diversity to your program. Before attending the University of Northern Iowa, I was employed in the music industry, construction, restaurant management, and sales. I view these years as invaluable, as they have shaped my motives, compelled me to appreciate the need for goal orientation, and allowed me to experience the triumphs and frustrations of the "real" world. Consequently, I entered my college career with a strong sense of purpose. This sense of purpose is reflected in my activities relevant to Industrial/Organizational Psychology, which have been under the continuous and invaluable guidance of Dr. Dave Whitsett, Professor of I/O Psychology, University of Northern Iowa. In January of 1993, I approached the Human Resource Department of John Deere Tractor Assembly Division, Waterloo, Iowa, with the intention of gaining hands-on experience in a manufacturing setting. I have, under the supervision of Marshal C. Chesmore, Senior Human Resource Representative, researched Self-Directed Work Groups and served on the "Changing Role of the Supervisor" committee. I am continuing my involvement by serving on a subcommittee responsible for developing a training needs analysis for the Central Training Division of John Deere Waterloo Works. Feeling a need to diversify my experience, I approached GMAC Mortgage of Waterloo, Iowa, about the possibility of a credited internship. I am currently reviewing their personnel processes via interviews with appropriate personnel and examination of existing documentation. This project will culminate in a modal description of these processes, and recommendation for process/organizational modification. I have prepared myself academically for advanced graduate study in I/O Psychology through relevant college course work, such as Organizational Psychology, Personnel Psychology, Principles of Psychological Testing, Statistics for Psychology, and Research Methods in Psychology. I have conducted research, under Dr. Augustine Osman, Clinical Psychologist, University of Northern Iowa, on the psychometric properties of the "Inventory of College Students in Recent Life Experience.

Primacy Effect

Primacy Effect is a cognitive bias that results from disproportionate salience of initial stimuli or observations. It is the tendency to remember well the first items, that will influence us more than the later information will. According to Solomon Asch (1946), â€Å"a glance, a few spoken words are sufficient to tell us a story about a highly complex matter† (pg. 258). Therefore, we often make our judgment of the person right from the first impressions. For example, if someone makes a good first impression the moment they meet you, you will tend to dismiss negative attributes shown later in the person.However, if someone were to make a bad first impression, they will have a hard time making a positive influence later on. In one study, the Asch had presented a list of six adjectives to a subject. It was revealed that subjects who had flattering descriptors were picked to be more likeable when their adjectives were in order from favorable to unfavorable. Therefore humans perce ive the people around them by their independent trait. Humans often fill in the gaps of missing information. In another study that Asch (1946) conducted, the two different subjects were shown 2 lists A. bedient-weak-shallow-warm-unambitious-vain B. vain-shrewd- unscrupulous-warm-shallow-envious (pg. 267) results shows that the subjects were more influenced by the words that came before warm. They felt that in series A, the person was truly and genuinely a warm person. However, in series B the subjects felt that the warmth in the person lacks sincerity. (Asch, 1946, pg. 267). This clearly displays the primacy effect that humans different judgment of two different first impression, however with a similar central trait warm.Therefore, we would perceive people with better physical appearances as more socially desirable and that the first impressions of them will be positive. Even if there were to be signs of any negative characteristics, humans tend allow these first impressions to beco me self-fulfilling prophecies and be naturally biased towards them. Reference: Asch, S. E. (1946). Forming impressions of personality. Journal of Abnormal and Social Psychology, 41(3), 258-290