Effect Of Sleep On Memory Essays - Sleep, Memory,

Effect Of Sleep On Memory Effect of Sleep on Memory This article is from The Journal of Experimental Psychology, and was written on an experiment performed by psychologist Bruce R. Ekstrand, from the University of Colorado. He experimented on the effects that sleep has on ones memory, after learning a particular bit of knowledge, in this case a certain list of twelve three-letter words. There were several different ways Ekstrand went about discovering whether sleep would facilitate memory or not. Out of the entire group of people who he experimented on, some of them were given nothing but a simple list to memorize, some were given a pro-active interfering list, and some were given a retroactive interfering list. For his core measurement method, he used a 3x2 factorial chart. In this factorial were the three types of interference learning he used- retroactive, pro-active, and no interference. The factorials two-part were the levels of sleep that those who were experimented on got either eight hours of sleep, or none. The participants would have to learn these certain lists and associations with the lists, and perhaps pro-active or retroactive learning if they were assigned to that particular group. Half of the participants, chosen at random, would then sleep in the laboratory for approximately eight hours before being awakened in the morning, being urged to fall asleep as soon as they could, and with the average time it takes on to fall asleep being taken into account. Those who had to stay awake would leave for eight hours and return. Both groups would assure that no rehearsing had been done, and they would then have to recall the lists and associations. In most of the rehearsals for testing, sleep proved to facilitate recall better than staying awake did. However, the facilitation was not incredibly significant. In some of the pro-active and retroactive cases, sleep did not actually facilitate memory at allboth sleeping and awake people tested equally. I chose this particular article because I wanted to use its results to my benefit. I am always looking for ways to better prepare myself for tests, and better strategies for studying, both to learn more at one time, and to cut down on my entire studying time. Furthermore, I absolutely love to sleep, so I was hoping I could use this article as an excuse to sleep more, or as my rationale for sleeping often, assuming that I would study and then go to sleep. Some other articles I browsed through did not seem as interesting as this one, and I figured since this article was both interesting and helpful to me specifically, I would choose this one to write about. I have to admit that this article was a bit hard to comprehend, and quite hard to follow. I did manage to eventually understand most of it, but some of it was just impossible to grasp. Some of the language and terms used in this article are ones that I would have no way of knowing yet, based on my knowledge from psychology class. The writer used many abbreviations and symbols for certain procedures and items involved in the experiment, which made his sentences hard to follow at times. However, from eventually being able to understand it all, this article proved to be useful to me. I will definitely try to study more in the future, and then get to sleep right afterward. As I mentioned earlier, I am always looking for ways to improve my study habits and knowledge acquired from studying, and this article helped me with this quest. As a result of my reading, I learned that there is a good chance that sleeping after studying something will help me to remember it. I learned that I may need to change my study habits a little, to give myself more time to sleep after studying! This article did relate to in class material. It related specifically to the chapter we studied on memory. I could better understand this article because I had learned about memory, mainly about pro-active and retroactive inhibition. I believe some of the chapter discussed certain ways of learning and remembering, and this article definitely pertained to that topic. Overall, I would

Comparision contrast essays

Comparision contrast essays The cougar population is rising every year in Oregon and the population is moving closer to urban areas. As a result, cougar attacks are increasing. Management of the cougar population has become a political issue that sparks many debates. It is not too often anyone ever sees a cougar but they are out there. We walk threw the woods not even thinking of these creatures, but they are thinking about us and watching us. Sometimes cougars are too interested in us and our domestic animals, and this usually ends up with an injury or even death. The Oregon Department of Fish and Wildlife (ODFW) is responsible for maintaining a plan to manage the cougar population in Oregon. By examining ODFWs figures we can see that the population is rising. Prior to 1994 the annual growth rate was estimated at four to five percent. In 1994 a new law came into effect. Oregon Administrative Rule (OAR) 635-067-004(5) was put into place to ban the use of dogs for hunting or pursuing cougar. After the ban, the growth rate increased to approximately eight to twelve percent per year. ODFW states that, increased observations, road kill incidents and increasing damage complaints indicate the statewide cougar population has increased substantially since 1980. The new law was put into effect after a campaign alleged that the use of hounds was too cruel. However, without the use of hounds hunting the cougar has become to difficult. According to statistics on ODFWs website, from 1970 to 1994 hunters had an average success rate of 42%. From 1995 to 2000 the rate was down to a five percent average. To find a cougar without a dog is like searching for a needle in a hay stack. You must have a dogs nose to pick up on the sent of a cougar, a humans nose will not do. Cougars can smell and hear an approaching human long before the human is aware of the presence of the cougar. As they approach the cougar it will continue to ...

Culture, Social Status and Identity in Viramontes' The Months and Essay

Culture, Social Status and Identity in Viramontes' The Months and Tan's Rules of the Game - Essay Example These stories are the same because they depict the cultural and social status of their characters, and the main protagonists want to mold identities that conflict with their society’s beliefs about womanhood, but they are different, because they discover dissimilar sanctuaries, where they can be, who they are, without being judged. These short stories are the same, because they portray the cultural and social status of the characters. The beliefs and practices of the protagonist in â€Å"The Moths† demonstrate that she comes from a conservative and patriarchal society. This society demands their women to be submissive and skilled in feminine tasks and values, such as crocheting. Her father, who she calls Apa, often gets angry with her, because she dislikes going to church. As part of their conservative and religious culture, they are expected to go to mass every Sundays, especially decent girls and women. But she does not does not like the church, because its â€Å"vas tness† makes her feel alone (Viramontes). Likewise, in â€Å"Rules of the Game,† Waverly’s Chinese is culture is very conservative, where hierarchies exist. On top of the family hierarchy are parents, who children will and should never disobey. When Waverly’s mother says this, she embodies the â€Å"strong wind† in her daughter’s life: â€Å"Strongest wind cannot be seen† (Tan). She cannot see her mother, who is always at her back, watching and commenting on her every move, not only in chess, but in real life. The social status of the characters is also evident in the settings of the story. The protagonist in â€Å"The Moths† lives in a place where superstitions are respected. Her grandmother mixes dried moth wings with Vicks to soothe her â€Å"bull hands† and shrink them back to normal size (Viramontes). Her grandmother also has stomach cancer, but they do not have money to pay for expensive therapies. Similarly, Waverl y lives in a poor community, although she is not aware that she is poor. They live on a â€Å"†¦two-bedroom flat that sat above a small Chinese bakery† (Tan). It signifies living in a cramped and controlled space, where Waverly cannot expect to express her freedoms. These stories are also the same, because the female protagonists challenge their cultures, in order to form their identities. The protagonist in â€Å"The Moths† does not believe in following cultural norms about womanhood. Instead of learning how to crochet, she learns how to plant with her grandmother. Her â€Å"bull hand† signifies that she does not fit with her society, because her personality, preferences, and beliefs oppose female stereotypes and Christian norms. When she smells the chile, she cries not only because of the chile’s spice on her eyes, but also because of herself. She is like a chile that hurts the feelings of her family, who wants her to be someone she is not. She is also compared to the â€Å"defiant† sun, because they both resist changing for others (Tan). When the sun meets the land during sunset, the union depicts that â€Å"endings† are windows to â€Å"rebirths† (Tan). But if she will be reborn, she will be the same pertinent and critical daughter that makes Apa angry and disappointed. Also, Waverly defies her culture, by becoming a great chess player and toppling every other man or boy she plays with. Moreover,

OOS-Deviation assignment detecting the presence of diethylene glycol Essay

OOS-Deviation assignment detecting the presence of diethylene glycol in toothpaste by thin layer chromotography - Essay Example Additionally, for detection purposes, you will require 6.7 mg/mL of developing the solvent of Potassium Permanganate Staining Solution. Centrifuge tube of 50mL polypropylene to sample a preparation of toothpaste with a weight of around 1.0g. To disperse the toothpaste, add 5mL of water and vortex for around 1 minute. Next is the addition of 5mL of acetonitrile to the mixture followed by vortex about 1 minute. Prior to collecting around 1mL of the supernatant, centrifuge the mixture until you obtain a crystal-clear solution. Make use of the 1.5mL micro test tubes by transferring 500L of the supernatant to it then add 1.0mL of methanol. Dilute 0.2mL of DEG to 0.5mL using methanol in order to achieve the standard reference preparation (Ahuja & Scypinski, 2011). Spread the 5L diluted test solution and the reference standard solution on a sheet and leave it to dry. To get commendable results, use chromatographic procedure spot. The next step is to put the sheet in a developing tank that has been prepared by balancing 100mL of developing a solvent for about 30minutes. Remove the solvent and permit it to dry in the air immediately the developing solution reaches the stopping line. When you submerge the dried sheet in potassium permanganate solution and then remove the sheet after around 5 seconds, yellows spots will start to appear on the background as the sheet begins to dry. The last spot to appear is DEG. The reading of DEG varies from 0.40%, 0.41% and 0.44% for OOS results and between 0.005% and 0.015% for OOS deviation. According Ahuja and Scypinski (2011), after the examination of the OOS results, the procedures on the discovery and occurrences of the OOS are

PERSPECTIVES ON EFFECTIVE LEADERSHIP BEHAVIOUR Case Study

PERSPECTIVES ON EFFECTIVE LEADERSHIP BEHAVIOUR - Case Study Example Though a questionnaire is an appropriate research tool to measure leadership behaviour and its impact on the organization, it does have limitations. These limitations include response bias, which involves stereotypes or favoritism shown toward the leader by the respondents that can distort results. There may also be social norms that exist within the organizational culture that have established a leader is effective even though such effective behaviours have not been observed personally by respondents. Therefore, the respondents may provide information within the questionnaire format that they believe will satisfy these social norms about the leader. There may even be problems with reliability with the research instrument, the questionnaire, that is not developed with questions that accurately measure what is intended to be understood. Causality is defined as a cause and effect phenomenon where situation x occurs as a direct result of activities stemming from situation y. When measur ing leadership, causality might be whether leadership behaviour x has a direct impact on employee motivation y. Consider the following: An organizational leader is using a questionnaire format to determine whether motivation is being negatively affected by improper leadership. Correlations are being sought in relation to the respondent information returned from the research tools.

Effect of Curcumin on Periodontis

Effect of Curcumin on Periodontis INTRODUCTION Periodontitis is a chronic inflammatory disease characterized by destruction of the soft and hard tissues supporting the tooth. This tissue destruction appears to result from complex interaction between the bacteria and the host’s immune and inflammatory system. The host immune response identifies these invading pathogens and tries to neutralize or kill these microorganisms. During this process the host response elaborates a variety of mediators such as pro-inflammatory mediators, cytokines and proteolytic enzymes such as matrix metalloproteinases (MMPs). It is now believed that the major component of the soft and hard tissue destruction seen in periodontitis occurs as a result of activation of these mediators.1 Thus this host response which is essentially protective by intent paradoxically can also result in tissue damage. Hence recent therapeutic efforts are now focusing on altering or modulating this host response. This lead to emergence of a new comprehensive treatment str ategy for periodontitis which involves Host modulatory therapy (HMT) which can be combined with traditional periodontal therapies.2 To date, there is one FDA approved, systemic therapy that is prescribed as a host response modifier in the treatment of periodontal disease and that is adjunctive subantimicrobial dose doxycycline (SDD), which down-regulates the activity of MMPs.3 These MMPs are considered to be primary proteinases involved in periodontal tissue destruction synthesized by a variety of infiltrating inflammatory cells (i.e. neutrophils and macrophages), resident cells and some bacteria. Numerous studies have substantiated the relationship between MMPs and periodontal diseases, with findings of significantly higher MMP-9 (neutrophil derived MMPs) levels in patients with periodontitis compared to healthy controls.4, 5 Doxycycline is the most potent tetracycline for inhibition of these MMPs.6 However long term tetracycline therapy has certain disadvantages, the most important being the development of microbial resistance to this drug.7 At present a health care system exists in India where different types of diseases are being treated by Ayurvedic method. Since ancient times Ayurvedic drugs are being used for the treatment of various diseases, including periodontal and other oral diseases.8 They are widely acclaimed for their minimal side-effects and cost-effectiveness. Use of herbal extracts in treating periodontal diseases does not produce side effects of tetracycline compounds as well as other synthetic drugs. Curcuma longa (Turmeric) is a widely used herb which is distributed throughout tropical and subtropical regions of the world and widely cultivated in India, China and Indonesia.9 It has also long been used in both Ayurvedic medicine and Chinese medicine as an anti-inflammatory agent.9 The active constituent in turmeric is Curcumin.9, 10 Curcumin is known to have an anti-inflammatory effect. Studies show that Curcumin limits the activity of two enzymes, lipoxygenase and cyclooxygenase-2 that are involved in promoting and maintaining inflammation.11, 12 Studies have also shown that Curcumin down-regulates the MMP-9 activity.13, 14 Thus it may have a potential role in the treatment of inflammatory periodontal disease. Its anti-inflammatory activity in periodontal diseases has not been extensively investigated. With this background, the study was conducted to evaluate the anti-inflammatory effect of Curcumin by its inhibitory effect on MMP-9 activity and compare the same with Doxycycline, which is known to have an anticollagenase activity. MATERIALS AND METHODS Subjects: A total of 30 sites from 30 subjects (males and females), above 35 yrs of age, diagnosed clinically as having Chronic Periodontitis with pocket depths ranging from 5-8mm were selected for the study. The patients had no history of pervious dental treatment, antibiotic or anti-inflammatory drug therapy for the past 6 months. Patients with any history of systemic diseases / conditions, pregnant patients and smokers were excluded from the study. An informed consent was obtained from the patients prior to their enrollment into the study, and the study has been independently reviewed and approved by the institutional ethical board. Post collection of samples, the patients who participated in this study received the standard treatment protocol for Chronic Periodontitis. Method of Collection of Samples: Gingival tissue samples were obtained under aseptic conditions after administration of local anesthesia from patients who were diagnosed with Chronic Periodontitis. Gingival tissue samples were obtained from sites with pocket depths ranging from 5-8mm. Immediately following excision, these tissue specimens were briefly washed under cold distilled water and blotted dry. Then the specimens were transferred into sterile plastic vials which contained Phosphate Buffer Solution (PBS), pH 7.2, that acted as the transport medium. Specimens were then immediately carried to the laboratory where they were stored at -80à ¯Ã¢â‚¬Å¡Ã‚ °C until use. IN-VITRO STUDY Chemicals Used: Pure extract of Curcumin in powder form (Samy Labs, Bangalore, India) and Doxycycline i.e. pure doxycycline hyclate in powder form (Aristo Pharmaceuticals Limited, Bangalore, India) was used for the purpose of the study. The Curcumin solution was prepared by dissolving 15mg of Curcumin in 10ml of distilled water (1500 ÃŽ ¼g/ml). Preparation of Doxycycline solution was by dissolving 3mg of Doxycycline in 10ml of distilled water (300 ÃŽ ¼g/ml). Extraction of MMP-9: The frozen gingival tissue samples were allowed to thaw to room temperature. Then each tissue sample was homogenized with 2.5% Triton X-100. This was followed by centrifugation of the homogenized samples for 30 mins at 6000 rpm, at 4à ¯Ã¢â‚¬Å¡Ã‚ °C. The resulting supernatant was separated and used for analysis. Detecting the Optimal Curcumin and Doxycycline Concentration: To determine the optimal inhibition of MMP-9 by Curcumin, different concentrations of Curcumin i.e. 300, 500, 1000, 1500 ÃŽ ¼g/ml were added to 50ÃŽ ¼l of gingival tissue extract and incubated at room temperature for 60mins.The addition of increasing concentrations of Curcumin to the gingival tissue extract resulted in decreased MMP-9 activity as shown in Figure 1. Assessing the MMP-9 activity by Densitometric Analysis demonstrated that the concentration of Curcumin required to inhibit more than 50% of MMP-9 activity was 1500 ÃŽ ¼g/ml. Since Curcumin showed more than 50% inhibition of MMP-9 activity at a concentration of 1500 ÃŽ ¼g/ml as compared to the control (without drug), this concentration was used to pretreat the gingival tissue extract in the study. The Curcumin solution with a concentration of 1500 ÃŽ ¼g/ml was freshly prepared prior to processing of each sample of gingival tissue extract. Similarly increasing concentrations of Doxycycline ie 50, 100, 200, 300ÃŽ ¼g/ml were added to 50ÃŽ ¼l of gingival tissue extract and incubated at room temperature for 60mins. Assessing the MMP-9 activity by Densitometric Analysis demonstrated that the concentration of Doxycycline required to inhibit more than 50% of MMP-9 activity was 300ÃŽ ¼g/ml and thus this concentration was used to pretreat the gingival tissue extract in the study. The Doxycycline solution with a concentration of 300ÃŽ ¼g/ml was freshly prepared prior to processing of each sample of gingival tissue extract. Pretreatment of Gingival Tissue Extract with Curcumin and Doxycycline: To compare the inhibition of MMP-9 activity, 50ÃŽ ¼l of gingival tissue extract was preincubated with freshly prepared solution of 50ÃŽ ¼l of Curcumin (1500ÃŽ ¼l/ml) and 50ÃŽ ¼l of Doxycycline (300ÃŽ ¼l/ml) solution for 60mins at room temperature in separate vials. In addition, 50ÃŽ ¼l of extract was also incubated with 50ÃŽ ¼l of distilled water which was used as the control. Assay for MMP-9 Activity: The presence of MMP-9 activity in collected samples was studied by gelatin zymography. Sodium Dodecyl Sulphate-Poly Acrylamide Gel Electrophoresis (SDS-PAGE) on 10% polyacrylamide containing 10% SDS copolymerized with 1g/l gelatin was used to pretreated tissue extracts under non reducing conditions without prior boiling. After electrophoresis, in order to regain the enzyme activity, the gels were rinsed with 2.5% Triton X-100 for 1hr to remove SDS thus allowing the protein to denature. The gels were then immersed in a proteolysis buffer containing Tris- HCl 50 m M/l (pH 7.6) and CaCl2 20mM/l and incubated at 37  ºC for 16 hours. The gels were subsequently stained Coomassie Blue (0.25% Coomassie Brilliant Blue R250, 40% methanol, 10% acetic acid). Gels were destained (30% methanol, 10% acetic acid and 60% water) until white bands appeared clearly from the blue background. These bands of gelatin lysis detected against the blue background as seen in Figure 2, represented enzymatic act ivities. RESULTS The presence of MMP-9 was studied. The enzymatic activities were detected as unstained bands on gelatin gel by zymography technique. In order to measure the relative MMP-9 levels, multi-image gel documentation systems were used to scan the clear zones and the percentage of inhibition was analyzed. Significant differences were found in the MMP activity in treated groups compared to the control. Figure 3 illustrates the reduction in the MMP-9 activity of each sample of gingival tissue extract when incubated with Doxycycline and Curcumin, expressed as percentage of reduction from the control. Table 1 shows the range, mean values and the standard deviation (S.D.) values for Curcumin and Doxycycline. The mean values show 59.58 % reduction in the MMP-9 activity with the addition of Doxycycline and 61.01% reduction in the MMP-9 activity with addition of Curcumin to the gingival tissue extract under identical conditions. Table 2 shows comparison of MMP-9 inhibitory effect between Doxycycline and Curcumin. The results obtained were analysed statistically using students paired t- test. DISCUSSION Periodontal diseases are the result of destruction of the soft and hard connective tissues surrounding and supporting the teeth. Inflammation is the basic cause of initiation of this breakdown. Research in the field of pathogenesis of periodontal disease has shown that various enzymatic activities which are directed towards the destruction of the pathogen also result in destruction of the periodontal connective tissue. Research has shown that, Matrix metelloproteinases (MMP’s) are one group of enzymes which are responsible for this destruction to a large extent. MMPs are involved in a number of physiological events including, tissue remodeling and pathological diseases such as periodontal disease and are the major players in collagen breakdown during periodontal destruction. MMPs are normally tightly regulated and disruption of this regulation leads to the pathologic breakdown of connective tissues. Higher levels of MMPs in the periodontal tissues provoke an imbalance between the production and degradation of collagen, causing tooth attachment loss. Especially, PMN derived MMPs (MMP-8 MMP-9) are the main proteinases related to tissue destruction and remodeling events in periodontal diseases. Numerous studies have substantiated the relationship between MMPs and periodontal diseases, with findings of significantly higher MMP-9 levels in patients with periodontitis as compared to healthy controls.4, 5, 15 With this understanding of the role of host immune response in periodontal destruction the possibility of host modulation so as to reduce the destructive aspects of the host response and hence reduce the damage to the periodontium was investigated. First group of drugs that showed this host modulation activity were Tetracyclines. Studies have demonstrated that tetracycline could significantly inhibit collagenase activity in GCF and gingival tissue, even at lower dosage than traditional antimicrobial dosages ie sub antimicrobial dosage.3 Tetracyclines inhibit collagenases by binding to the Ca2+ or Zn2+ (cations) required for the activation of MMPs such as collagenases and gelatinases.16 It is also possible that tetracyclines can inhibit synthesis of neutrophil-derived oxygen radicals, suppressing neutrophil migration and degranulation.17 However, microbial resistance to tetracyclines has been reported.7 In addition, long term treatment can result in other side- effects such as anorexi a, nausea, epigastric distress and fatty liver. A few recent studies on collagenase inhibition suggested that, like tetracyclines, herbal extracts are also potent inhibitors of pathologically elevated collagenases and hence they may be used as an alternative adjunct in the management of periodontal diseases.18, 19 Ayurvedic drugs like Neem, Triphala, Bakul etc have been used therapeutically since ancient times to treat diseases, including periodontal diseases. With the advent of modern synthetic drugs their convenience of standardized dosage form, dramatic efficacy in acute conditions and most of all simplicity of usage, there was a decline in the use of the plant medicines. But a long term treatment, with these synthetic drugs, has many adverse effects and they are also not cost effective. As Ayurvedic drugs, are widely acclaimed for their minimal side-effects and cost-effectiveness in India, they are now again being used extensively in treatment. Use of herbal extracts in treating periodontal diseases does not produce side effects of tetracycline compounds as well as other synthetic drugs. It has been shown that certain ayurvedic medicines also have the host modulation effect, similar to that of tetracyclines. A few recent studies conducted on collagenase inhibition by herbal extracts suggest that, like tetracyclines, herbal extracts are also potent inhibitors of pathogenically elevated collagenase and hence may be used as an alternative adjunct in the management of periodontal diseases.18, 19, 20 Turmeric which has Curcumin as its active constituent has been shown to have anti-inflammatory, anti-oxidant, anti- bacterial, anti- viral activities etc.10 Its anti- inflammatory activity has not been investigated in periodontal diseases. With the above details in mind the present study was conducted to evaluate the anti-inflammatory property of Turmeric. In the present study the anti-collagenase activity of Curcumin was compared with that of Doxycycline which has proven anti-collagenase activity. In the present study we chose Doxycycline because it has been proved that it is a more potent collagenase inhibitor as compared to minocycline and tetracycline.6 Studies have shown that Curcumin down-regulates MMP-9 activity13, 14, 21 and thus, in the present study we chose Curcumin to find out its anti-collagenase activity by checking its effect on MMP-9 activity. Research has shown that the predominant MMPs in inflamed gingival and periodontal tissues are PMN- type MMPs (MMP-8 MMP-9). Elevated activity of gelatinases (MMP-2 and MMP-9) has also been found in inflamed gingival tissues from chronic periodontitis patients.5, 22 The activity of PMN- type MMPs has been found not only to positively correlate to the severity of inflammation and pocket depth but also the amount of these enzymes recovered in an active rather than latent form appears to increase with greater severity of periodontal disease in the gingival tissue.20 Thus, since the above studies have shown that activity of PMN- type MMPs is increased in inflamed gingival tissues, in the present study we decided to use gingival tissue samples that were obtained from the patients diagnosed clinically with chronic periodontitis. The reduction in the MMP-9 activity of each sample of gingival tissue extract when incubated with the drugs .i.e. Doxycycline and Curcumin, was expressed as percentage of reduction from the control (without drug). The mean values showed 59.58% reduction in the MMP-9 activity with the addition of Doxycycline and 61.01 % reduction in the MMP-9 activity with addition of Curcumin to the gingival tissue extract under identical conditions. These results show that Curcumin has a significant inhibitory effect on PMN-type MMP-9, and this inhibitory effect of Curcumin is comparable to that of Doxycycline when the percentage of inhibition as compared to control was analysed. Curcumin also showed a significant reduction in the MMP-9 activity with an average inhibition of about 61% which is also statistically highly significant (p 23 and 12 g per day.24 But the overall results show that Curcumin has the ability to significantly inhibit the MMP-9 activity. The present study suggested that Curcumin could produce significant inhibition of MMPs at 1500 ÃŽ ¼g/ml concentration, which is well under the safe drug profile confirmed by toxicological studies.23, 24 Thus this study shows that Doxycycline and Curcumin possess anticollagenase activity in vitro. The finding of the present study is significant and confirms the use of Curcumin in treating periodontal diseases. A recent in vivo study showed that Curcumin modulates periodontal disease and had potent anti-inflammatory effects when it was systemically-administered in ligature-induced periodontitis in rats.25 Studies have shown that one of main mechanisms for the anti-inflammatory effects of Curcumin may be the inhibition of NF-ÃŽ ºB (nuclear factor kappa B).13, 25 The Curcumin-mediated inhibition of MMP-9 gene expression appears to occur via NF-ÃŽ ºB and AP-1 (Activator Protein-1) because their DNA binding activities were suppressed by Curcumin.14, 21 When compared to tetracycline, Curcumin has better anti-inflammatory effect, is more cost effective and has minimal side effects and thus can be tried as a substitute for Tetracycline as an anticollagenase agent. Curcumin also allows suppression of collagenase activity well within the safe dosage profile confirmed by toxicological studies. The in vivo environment is substantially different, and inherent limitations of an in vitro replication may constrain our understanding of the systemic effects of Curcumin. Further in vivo studies of Curcumin are needed to define its toxicological profile before making it a part of the therapeutic regimen in periodontal treatment. CONCLUSION In the light of observations from the current study it can be concluded that Doxycycline and Curcumin possess anticollagenase activity in vitro. Since Curcumin has better anti-inflammatory effect compared to Tetracycline, Curcumin being more cost effective and with no side effects can be tried as a substitute for Tetracycline as an anticollagenase agent. Thus Curcumin may have therapeutic potential as a host modulation agent in periodontal diseases.

H.G. Wells :: English Literature

H.G. Wells Herbert George Wells was born in 1866 in Bromley, Kent. His career as an author was fostered by an unfortunate accident as a child. He broke his leg and spent the mandatory rest period reading every book which he could find. Wells was awarded a scholarship and furthered his education at the Normal School of Science in London. It was at the Normal School that Wells came under the wing of the famous biologist Thomas H. Huxley. Wells' "science fiction" (although he never called it such)was clearly influenced by his studies at the Normal School and his interest in biology. H.G. Wells gained fame with his first major fiction work: The Time Machine in 1895. Soon after the publication of this book, Wells followed with The Island of Dr. Moreau (1895), The Invisible Man (1897), and perhaps his most famous popular work: The War of the Worlds (1898). Over the years Wells became concerned with the fate of human society in a world where technology and scientific study were advancing at a rapid pace. For a period he was a member of The Fabian Society, a group of social philosophers in London. Wells's later works became less science fiction and more social critique. The accuracy of the "science" in Wells's work has often been called into question. It is rumored that Wells and the French novelist Jules Verne actually criticized each other's writing. Wells's claim was that "Verne couldn't write himself out of a paper sack" and Verne accused Wells of having "scientifically implausible ideas." The science may not be accurate, but the adventure and philosophy in those books makes Wells' early science fiction fun and fascinating to read. Herbert George Wells was born in 1866 in Bromly, a small town near London. He attended college and graduated with a degree in biology. His lower-middle-class background and his knowledge of science influenced his writings. He thought that science would make a better world. He also thought that that humans would destroy their own race by having a big atomic war and eventually kill each other off. Some of the books Wells wrote were The Time Machine, The Invisible Man The War of the Worlds and The Island of Doctor Moreau. He was very famous in his lifetime, and his books sold well. His book War of the Worlds was a radio drama, performed on Halloween night in 1938. Many people tuned in after they said "This is only a story", so they thought that Martian aliens were attacking Earth. So people grabbed their rifles and jumped in their cars and took off. H.G. Wells died in his sleep on