The o-quinones, themselves, are colorless, however they react with other phenolic compounds and can self-polymerize to form compounds which produce the brown color associated with apple oxidation (Nicolas et al.). This oxidation process forms a thin brown layer on the exposed surface of the apple.
The rate of browning in different apple types is dependent on both the concentration of polyphenol oxidase and polyphenols within the apple (Nicolas et al.). Decreased levels of either component within the oxidation reaction can slow the browning process. Apples which exhibit slow browning are often specifically chosen by farmers and the food industry, leading to a genetic selection of fruits with lower or less active polyphenol oxidase and polyphenols (Nicolas et al.). The activity of polyphenol oxidase can also be perturbed by thermal denaturation via heating or by coating the exposed apple with ascorbic acid, thus lowering the pH (Nicolas et al.). Ascorbic acid…...
mlaWorks Cited
Kotz, John C., Paul Treichel, and John R. Townsend. Chemistry and chemical reactivity. Cengage Learning, 2008.
Nicolas, JJ et al. "Enzymatic browning reactions in apple and apple products." Critical Reviews in Food Science and Nutrition 34.2 (1994): 109-157.
ENVIONMENTAL CHEMISTYEnvironmental Chemistry1.a) An exothermic redox reaction involves the release of energy in form of heat after an oxidation-reduction reaction.b) The oxidation state of an element represents the charge of an atom after a redox reaction (Khan, n. d)c) A redox reaction involves a reduction and oxidation reaction where an atom either gains or loses electrons. The process can also involve the gain or loss of oxygen atoms in an atom (Khan, n. d).d) From the aspects above, it is important to note that energy is only released when electrons are transferred thereby losing their potential energy.2.a. During denitrification process which has the following balanced redox reaction: 5CH2O+ 4NO3-+4H+?2N2+ 7H2O+5CO2, CH2O is oxidized to CO2 while NO3- is reduced to N2. In addition, H+ is oxidized to H2O. In both CH2O and H+ there is addition of oxygen atom. In NO3 oxygen atom is reduced. Therefore, it would be prudent…...
mlaReferencesAgency for toxic substances and disease registry (n. d). Benzene. G. M. (1992). Metals and Microorganisms: A Problem of definition. FEMS Microbiological Letters, 100, 197-204.Khan, S (n. d). Oxidation and Reduction, [Video]. https://www.khanacademy.org/science/chemistry/oxidation-reduction/redox-oxidation-reduction/v/introduction-to-oxidation-and-reduction Kutty, M. N. (1987). Site Selection for Aquaculture: Chemical Features of Water. African Regional Aquaculture Center.Mitsch, W. J., Day, J. W., Gilliam, J. W., Grofman, P. M., Hey, D. L., Randall, G. W. & Wang, N. (2001). Reducing the Nitrogen Loading to the Gulf of Mexico from the Mississippi River Basin: Strategies to Counter a Persistent Ecological Problem. Bio Science, 51(5), 373-388.Reddy, R. (2008). Wetland Biogeochemistry in Wetlands. DeLuane. Sheppard, S., Long, J. & Sanipelli, B. (2009). Solid/liquid partition coefficients (Kd) for selected soils and sediments at Forsmark and Laxemar-Simpevarp. https://www.skb.com/publication/1951648/R-09-27.pdf United States Environmental Protection Agency (n. d). Gasoline Mobile Source Air Toxics. https://www.epa.gov/gasoline-standards/gasoline-mobile-source-air-toxics Vogt, C., Kleinsteuber, S. and Richnow H. (2011) Anaerobic benzene degradation by bacteria. Microbial biotechnology, vol. 4 (6) pp 710-724https://www.atsdr.cdc.gov/ Gadd,
al., 1993; Forman & Dickinson, 2003). Though nitric oxide is not involved in as many individual processes as hydrogen peroxide, or at least a lower number of processes have been identified in current research, its presence in too great an abundance can disrupt proper signaling and trigger alternative signaling pathways other than those normally utilized in redox signaling (Forman & Dickinson, 2003). These redox signaling pathways have the potential to promote the continued production of reactive oxygen species rather than contributing to the continued progression of the optimal redox signaling cascade, in which the production of O, H2O2, and other reactive oxygen species would be signaled to cease and normal intercellular environments would resume (Forman & Dickinson, 2003).
Conclusion
Research into the complexities of redox signaling in wound response and its implications for the healing process remains ongoing, and many current findings are still the product of a great deal of…...
mlaNitric oxide (NO) is involved in redox signaling in ways somewhat similar to hydrogen peroxide (H2O2); both are purposefully produced toxic elements used to cleanse wound areas of infectious agents and used to signal other healing processes to start, while at the same time becoming dangerous in and of themselves if not properly regulated (Nunoshiba et. al., 1993; Forman & Dickinson, 2003). Though nitric oxide is not involved in as many individual processes as hydrogen peroxide, or at least a lower number of processes have been identified in current research, its presence in too great an abundance can disrupt proper signaling and trigger alternative signaling pathways other than those normally utilized in redox signaling (Forman & Dickinson, 2003). These redox signaling pathways have the potential to promote the continued production of reactive oxygen species rather than contributing to the continued progression of the optimal redox signaling cascade, in which the production of NO, H2O2, and other reactive oxygen species would be signaled to cease and normal intercellular environments would resume (Forman & Dickinson, 2003).
Conclusion
Research into the complexities of redox signaling in wound response and its implications for the healing process remains ongoing, and many current findings are still the product of a great deal of conjecture. Still, enormous advancements have been made in this area of biochemical knowledge. As redox signaling and other aspects of wound healing are better understood, more effective methods for dealing with infections and slow healing times can be developed, and many in the world will truly experience better living through chemistry in a very direct way.
It was used by Michael Faraday in the 1800s in his experiments on electromagnetism. Other inventors improved on the battery's original design and these improvements produced telegraphs and doorbells. Napoleon onaparte was so impressed with the invention that he recommended honors for Volta, including making him a count in 1810 (CIRL, Rubin, Scratch, Corrosion Doctors).
From this first and crude battery evolved electrochemistry, electromagnetism, and modern applications of electricity (CIRL, 2011; Rubin, 2011; Scratch, 2011; Corrosion Doctors, 2011). Even the defeated principles of Galvani on animal electricity served as the initiative to the development of electrophysiology and modern biology. From Volta's name came the unit of electromotive force, called volt, while from Galvani's name was coined the galvanometer, the instrument for detecting and measuring small electric currents (CIRL, Rubin, Scratch, Corrosion Doctors).
Significance and Influence during the Industrial Revolution
It is when power is cut off that ancient means of illumination, such…...
mlaBIBLIOGRAPHY
CIRL. Alexander Volta Center for Integrating Research & Learning: National High
Magnetic Field Laboratory, 2011. Retrieved on February 21, 2011 from http://www.magnet.fsu.edu/education/tutorials/prioneers/volta.html
Corrosion Doctors. Alexander Volta. Corrosion Doctors.com, 2011. Retrieved on February 21, 2011 from http://www.corrosion.doctors.org/Biographies/VoltaBio.htm
HBCI. Nature Obeys Rules, Too. Hiawatha Broadband Communications, Inc.: Hayden
The energy it stores (?180 Wh kg?1) at an average voltage of 3.8 V is only a factor of 5 higher than that stored by the much older lead -- acid batteries. This may seem poor in the light of Moore's law in electronics (according to which memory capacity doubles every 18 months), but it still took a revolution in materials science to achieve it. Billions of lithium-ion cells are produced for portable electronics, but this is not sustainable as cobalt must be obtained from natural resources (it makes up 20 parts per million of Earth's crust). (Armand & Tarascon, 2008, p. 653).
Fu investigated the lithium-ion conductivities of glasses and glass-ceramics in the LI2O-AlO3-TiO2P2O5 system. Fu's samples revealed high conductivity, albeit when Abrahams and Hadzifejzovic similarly investigated the LI2O-AlO3-TiO2P2O5 glass and glass-ceramic systems, their findings revealed "a maximum room temperature conductivity of 3.98 x 10-6 S/cm in their crystallized…...
mlaREFERENCES
Armand, M & Tarascon, J.M. (2008). Building better batteries. Nature. Volume 451. Retrieved
April 17, 2010 from http://www.uio.no/studier/emner/matnat/kjemi/MENA5020/h08/undervisningsmaterial
BATTERIES.pdf
Battery power. (2010). Royal Society of Chemistry (RSC). Retrieved April 17. 2010 from http://www.rsc.org/Education/EiC/issues/2008Mar/BatteryPower.asp
Natural overburden includes silty clay, silty peat, and silty sand (CH2MHILL, p. 3-2). Overburden is generally thin, averaging 3 meters in most areas, but can go up to 9 meters at times (CH2MHILL, p. 3-2). Native soils primarily reside in areas of low topography.
This topography allows for constant movement and shifting of overburden. Rainy seasons create excessive water flows, which travel down slopes to the low-lying areas and into the waterways. These areas of low topography are of particular concern, as they tend to accumulate deposits of contaminants.
Groundwater and surface water in the area are altered by man-made structures placed by the mining company. ater travels through the area by means of the overburden and the bedrock. In the area of the main mine, water flows primarily through bedrock (CH2MHILL, p. 3-2).Groundwater flows in a generally southeasterly direction. ater flows towards the major waterways such as the Moira River…...
mlaWorks Cited
British Columbia Ministry of Environment. Arsenic in Groundwater. February 2007. www.env.gov.bc.ca/wsd/plan_protect_sustain/groundwater/library/ground_fact_sheets/pdfs/as (020715)_fin3.pdf
CH2MHill. Deloro Mine Site Cleanup. Mine Area Rehabilitation Alternatives. Final Report. Ontario Ministry of the Environment. 2003. http://www.ene.gov.on.ca/envision/techdocs/4915e.pdf .
McAndrew, B. Ministry kept town in dark over arsenic, group says. Tuesday 11 June 1999 the Toronto Star, http://www.e-b-i.net/ebi/Deloro/articles/del990611.html
US Environmental Protection Agency (USEPA). Arsenic in Drinking Water. 2006. http://www.epa.gov/safewater/arsenic/index.html
2005). The rules for deep-sea life are different than those for terrestrial species. Stratification plays an important role in species classification in vent environments. As the chimney grows in height the environment changes.
Tarasov and associates believe that deep-sea vents have a longer evolutionary history then shallow vents found closer to the surface. This is an important factor in understanding how hydrothermal vents are connected to early life on planet earth. Deep-sea hydrothermal vent communities represent a different phenomenon than shallow water vents. The chemical processes that take place in the deep-sea vent communities are very different from those in shallow areas. Shallow vent species receive light from the sun and more closely resemble terrestrial life forms. However, this is not so with deep-sea forms. Hydrothermal plumes are a rising column of hot water that can have sharp definitions in microhabitats. Similar species found inside the plume and outside of…...
mlaWorks Cited
DeChaine, E. And Cavanaugh, C. 2006. Presence of post larval alvinocaridid shrimps over south-west Indian Ocean hydrothermal vents, with comparisons of the pelagic biomass at different vent sites Journal of the Marine Biological Association of the United Kingdom, 86 (1): 125-128.
Govenar, B., Le Bris, N., and Gollner, S. 2005. Epifaunal community structure associated with Riftia pachyptila aggregations in chemically different hydrothermal vent habitats. Marine Ecology Progress Series,. 305: 67-77.
Jeng, M., Ng, K., and Ng, P. 2004. Feeding behaviour: Hydrothermal vent crabs feast on sea 'snow' Nature. December 2004. 432 (7020): 969.
Kelley, D., Karson, J., and Blackman, D. 2001. An off-axis hydrothermal vent field near the Mid-Atlantic Ridge at 30 degree N. Nature. July 12, 2001. 412 (6843): 145-149.
Drug Action
Pharmacokinetics explains the process by which a drug is absorbed, distributed, metabolized, and eliminated from the body. These processes are dependent on the amount of the drug administered, the method of administration (which affects the rate of absorption, biotransformation, and even excretion), and how the drug binds in the tissues. In essence, a drug's ability to transverse the cellular membranes depends on its solubility and molecular size and shape. The passive diffusion of the drug across cellular membranes depends on its lipid solubility as well as concentration gradients outside and inside the cellular membrane and the pH differences across the membrane. Active transport of the drug occurs when the drug is actually moved by components of the membrane. This can allow a drug move against concentration and electrochemical gradients but it requires energy, can be selective, and can be inhibited by similar molecules. The absorption rate is influenced by…...
Different Fuel Cell Technologies
U.S Department of Energy (2010) provides the description of different fuel cell technologies. The fuel cell technologies are differentiated according to their efficiency, operating temperatures, costs and application. The classifications are based on 6 major groups:
Alkaline fuel cell (AFC),
Phosphoric acid fuel cell (PAFC),
Solid oxide fuel cell (SOFC),
Molten carbonate fuel cell (MCFC),
Proton exchange membrane fuel cell (PEMFC);
Direct methanol fuel cell (DMFC).
Alkaline fuel cell (AFC)
The AFC generates electrical power using alkaline electrolyte KOH (potassium hydroxide) in water-based solution. The presence of hydroxyl ions within the electrolyte allows a circuit to extract electric energy. The illustration in Fig 2 reveals an alkaline fuel cell. As being revealed in Fig 2, two hydrogen gas molecules combines with 4 hydroxyl ions have a negative charge to release 4 electrons and 4 water molecules. The equation 4 reveals the reaction of oxidation that takes place. (Mark, 2003).
Equation (4)
(Oxidation) 2H2 + 4OH H2O +…...
mlaReferences
Andujar, J.M, Segura F. (2009). Fuel cells: history and updating. A walk along two centuries.
Renew Sustain Energy Rev. 13:2309 -- 22.
Grove, W.R. (1842). On a Gaseous Voltaic Battery. Philosophical Magazine and Journal of Science .vol. XXI: 417 -- 420.
Kordesch, K.(1999). Alkaline fuel cells applications, innovative energy technology. Austria: Institute of High Voltage Engineering, U Graz.
Cocoa
THE CACAO TREE (THEOBROMA CACAO)
WHAT IS IN THE COCOA BEAN?
MAKING AND EATING CHOCOLATE
State of the At of Cocoa
Is Cocoa good fo you?
Buden of Poof
CHOCOLATE AS A FAT
EFFECTS ON BLOOD LIPIDS
WHAT IS OK
CHOCOLATE AND HEALTH AND DISEASE
Chocolate Caving
F. Migaine
G. Toxicity
H. Immune Function
Allegy
J. Othe Disodes
K. Behavio
L. Antioxidants
M. Caffeine
N. Dental Caies
O. Migaines
P. Obesity
Seum Cholesteol
K. Heat Health
Pacemakes and vitamin pills ae just among a few of millions of health poducts that ae sold daily aound the wold. But one of the most easily accessible of all is ight beneath ou noses: chocolate. Cocoa, the plant fom which chocolate is deived, has had a positive effect on today's society because of its active ole in daily health. The development and distibution of cocoa has had a positive effect on today's society because of its active ole in daily health.
Many people believe that chocolate is bad fo you -- that it's caloies outweigh its positive…...
mlareferences for fats in foods: relationships to diet and body composition. Am J. Clin Nutr. 1991; 53:908-915.
Green SM, Delargy HJ, Joanes D. And Blundell JE A satiety quotient: a formulation to assess the satiating effect of food. Appetite. 1997; 29:291-304.
Seligson FH, Krummel DA and Apgar JR. Patterns of chocolate consumption. Am J. Clin Nutr. 1994;60:S1060-S1067.
Report of the Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults. U.S. Department of Health and Human Services, Public Health Service. National Institutes of Health; 1989. NIH Publication No. 89-2925.
Kritchevsky D. Effects of Triglyceride Structure on Lipid Metabolism. Nutrition Reviews. 1988;46:177-181.
Physiological Effects of Endurance Training
Endurance training produces many physiological changes, both during training and after the training period is complete. These changes are biochemical and also involve changes in the cardio-pulmonary system. The correct way to perform endurance training has been a subject of controversy in recent years. There are many differences in training methods. These differences and the effects of endurance training will be the subject of this research. The jury is still out as to what constitutes the perfect duration and intensity of training program.
Studies have shown that a focused training program can increase maximum oxygen intake by 15-30% over a three-month period (7) and that can increase to 50% if the training is sustained for over 2 years. The body makes many metabolic adaptations as well. These adaptations drop rapidly in the first few weeks after training is stopped (1).
Duration and Intensity of Different Training Programs
There are…...
mlaReferences
1. Acevedo EO, Goldfarb AH. Increased training intensity effects on plasma lactate, ventilatory threshold, and endurance. Med and Sci in Sports Exercise, (21), 563-568, 1998
2. Finn, C, Effects of High-Intensity Intermittent Training on Endurance Performance. Sportscience (5)(1), sport sci.org. Jour. 1-3, 2001.
3. Foss M.L., and Keteyian S.J. Fox's Physiological Basis for Exercise and Sport. WCB Boston, Mass., McGraw-Hill. 1998.
4. Hawley JA, Myburgh KH, Noakes TD, and Dennis, SC. Training Techniques To Improve Fatigue Resistance And Enhance Endurance Performance. Jour of Sports Sci, (15), 325-333, 1997.
Contaminants in Drinking Water and Wastewater and Effects on Environment
Drinking water and wastewater contamination pose a significant threat to the public health sector. The contaminants affect the society in various ways, including causing diseases, developmental and growth problems. The causes of the problem are identifiable and can be managed by using the most applicable strategies. As such, necessities for the adoption of strategies that will help identify the contributing factors, results and adopt effective strategies that will prevent and reduce waterway pollution. Therefore, the research provides analysis on the effects, studies, and recommendations appropriate in reducing drinking water and wastewater contamination.
Introduction
A number of chemicals play a significant role in influencing human activities of the daily living. They enable the development of new technologies and improve the standards and quality of life. Because of the widespread use of technology, chemicals enter the environment. Although, it is unintentional in most cases, some…...
mlaReferences
Altaf, M.M., Masood, F., Malik, A., 2008. Impact of Long-Term Application of Treated Tannery Effluents on the Emergence of Resistance Traits in Rhizobium sp. Isolated from Trifolium alexandrinum. Turk J. Biol. 32, 1 -- 8
Bolong, N., Ismail, A.F., Salim, M.R., Matsuura, T., 2009. A review of the effects of emerging contaminants in wastewater and options for their removal. Desalination 239, 229 -- 246
Chen, M., Ohman, K., Metcalfe, C., Ikonomou, M.G., Amatya, P.L., Wilson, J., 2006. Pharmaceuticals and Endocrine Disruptors in Wastewater Treatment Effluents and in the Water Supply System. Water 41, 351 -- 364
Focazio, M.J., Kolpin, D.W., Barnes, K.K., Furlong, E.T., Meyer, M.T., Zaugg, S.D., Barber, L.B., Thurman, M.E., 2008. A national reconnaissance for pharmaceuticals and other organic wastewater contaminants in the United States -- II) Untreated drinking water sources. Sci. Total Environ. 402, 201 -- 216
d.).
The primary organ that is accountable for regulating metabolism is the hypothalamus. The hypothalamus is situated on the brain stem and forms the floor and part of the lateral walls of the third ventricle of the cerebrum. The main functions of the hypothalamus is to control and integrate activities of the autonomic nervous system (ANS), production and regulation of feelings of rage and aggression, regulation of body temperature and regulation of food intake (Graham, 2005).
BM goes down with age and with the loss of lean body mass. Increased muscle mass and cardiovascular exercise can help to increase BM, even when the body is at rest. Measured in calories, metabolic rates vary with exertion, recent food ingestion, muscle exertion, environmental temperature, emotional state, body temperature, pregnancy, menstruation, level of thyroid hormones stress hormones (epinephrine and norepinephrine), fear and illness. The human body requires energy in order to stay alive and basal…...
mlaReferences
Basal Metabolic Rate. (2010). Retreived July 22, 2010, from Buzzle Web site:
http://www.buzzle.com/articles/basal-metabolic-rate.html
Basal metabolic rate. (2010). Retreived July 22, 2010, from Wellness.com Web site:
http://www.wellness.com/reference/fitness/basal-metabolic-rate/practice-theory-and-evidence
This means that their operation is totally opposite in direction, in fact a rechargeable battery can act as both a voltaic cell and an electrolytic cell depending on whether it is discharging or being charged. It is also practical to use the same type of metal as electrodes in an electrolytic cell while in voltaic cells the electrodes must be of different metals.
Since sodium is too reactive to freely occur naturally it exists in the earth's crust in a number of varied compounds such as halite. It can also be found in the form of sodium chloride and brine which are plentiful sea water. These compounds can be obtained by trapping the sea water or brine, or by mining rock salt. In order to obtain pure sodium metal, electrolysis of molten sodium chloride is done. This is achieved by using the molten sodium chloride as the electrolyte in an…...
mlaReferences
Asato, Robert. (2009). "Internet Chemistry." Electrochemical cells. Kapiolani Community
College. Retrieved on March 4, 2010 from http://library.kcc.hawaii.edu/external/chemistry/everyday_electro.html
Bodner Research Web (2009). Electrolytic cells. Retrieved on March 4, 2010 from http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch20/faraday.php
Sodium. (2006). World of chemistry. Retrieved on March 4, 2010 from http://www.bookrags.com/research/sodium-woc/
1).
This teatment, albeit, does not poduce 100% chitosan, but basically poduces a mixtue of 10-15% chitin plus 85-90% pue chitosan, called "pue CC." In the U.S., chitosan constitutes a mixtue of appoximately7% chitin plus appoximately 93% chitosan. Outside of cost-effectiveness, the biological effects of chitin poduced fom each souce appeas identical. "Chitosan oligosacchaides (CO) takes chitosan a big step futhe," Matsunaga (2007 explains. "When CC is ingested, a small amount of it is boken down into vey small molecula paticles by the enzymes of the body, thus poducing CO. CO can also be manufactued by using an enzymatic pocess" (Matsunaga, as cited in Levine, p. 1). The body moe eadily absobs CO, although CO contains less fibe than egula CC.
In Case Histoy 1: Low Pulmonay (Lung) Function, Matsunaga (Levine, 2007) teats his fist patient, also his fathe, with the administation of CC. Pevious teatments had yielded no esults fo…...
mlareferences and further reading you must purchase this article.
Lee, H., Park, Y., Jung, J. & Shin, W. (2003). Chitosan oligosaccharides, dp 2 -- 8, have prebiotic effect on the Bifidobacterium bifidium and Lactobacillus sp.
Elsevier Science Ltd. Retrieved November 2, 2009, from http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6W9T-48BKR97 -
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