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Natural Light (natural + light)
Selected AbstractsThe unmet treatment need of traumatized anterior teeth in selected secondary school children in Ibadan, NigeriaDENTAL TRAUMATOLOGY, Issue 1 2010Mojirade Deborah Ajayi The aim of this study was to assess the prevalence of damage to permanent anterior teeth in school adolescents, the average duration of trauma and to ascertain the level of the unmet treatment need. A total of 1532 secondary school children between the ages 12 and 19 years participated in the study. They were randomly selected from public secondary schools in five local government areas in Ibadan using a multistage sampling method. Participants were examined with the aid of mouth mirrors and probes under natural light. Traumatic anterior dental injuries were recorded by the same investigator (DMA) according to WHO classification. One hundred and sixty-five participants sustained injuries to their anterior teeth. Their mean age was 15.47 ± 2.09 years, with a male to female ratio of 1.5:1. The commonest cause was fall (78.8%) with road traffic accident being the least (1.8%). The tooth most commonly injured is the upper left incisor (48.0%) closely followed by upper right central (43.1%). Enamel fracture was seen in 46.5% and enamel,dentine in 42.6% of the traumatized teeth. Most (79.4%) of the children sustained injury to one tooth only. Of the participants, only 30 (18.2%) had previous dental consultation while only nine (5.5%) consulted the dentist following the trauma; however, none of the teeth had any form of restoration. Average time elapsed between trauma and dental examination was about 3.5 years. Many participants had had injury for about 2 years before dental examination. In conclusion, there is a high unmet treatment need of traumatized anterior teeth in the study population. [source] Comment on: Tattooing of skin results in transportation and light-induced decomposition of tattoo pigmentsEXPERIMENTAL DERMATOLOGY, Issue 1 2010Gregor B. E. Jemec Abstract:, Decorative tattoos have become a common feature of many societies. Their popularity appears mainly driven by fashion, and scant attention has been paid to any associated risk. The risks can be associated either with the tattooees' proclivity for risk taking in general, or with the substances used in the tattoos. It is well established that tattoo pigments wander widely in the body after they have been injected, and research now suggests that azo pigments may become mutagenic after exposure to either natural light or laser light. This may not only affect the risk profile of tattoos themselves, but also tattoo removal using lasers. [source] Sensitivity of Crops to Increased Ultraviolet Radiation in Northern Growing ConditionsJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 1 2002K. Hakala Crops growing at high latitudes are adapted to low intensities of solar ultraviolet B radiation (UV-B). As a result of destruction of stratospheric ozone layer especially at the Polar Regions of the globe, the intensity of UV-B is projected to increase at high latitudes. In order to find out the consequences of increased UV-B on crops, the sensitivity of different varieties of barley, wheat, oats, clover, timothy, meadow fescue, tall fescue and potato was tested in Jokioinen, Finland. The experiment was conducted in the field, under natural light, with a continuous 30 % increase in UV-B. Both increased UV-B and the control with slightly increased UV-A radiation affected the number of lateral shoots in cereals, and the specific leaf area and the content of phenolic substances in grasses. The effects varied according to plant variety and time of growing season. However, no visible damage, nor changes in biomass and yield production were found in any of the crops. Long-term effects on, e.g. genetic stability and germination of crop seed remain to be studied. Empfindlichkeit von Kulturpflanzenbeständen gegenüber einer Erhöhung der ultravioletten Einstrahlung unter nördlichen Wachstumsbedingungen Kulturpflanzenbestände, die unter hohen Breitengraden wachsen, sind an geringe Intensitäten der solaren ultravioletten B Einstrahlung (UV-B) angepasst. Aufgrund der Destruktion der Stratosphäre, insbesondere der Ozonschicht, im Bereich der polaren Gebiete der Erde, ist eine zunehmende Intensität der UV-B Strahlung in hohen Breitengraden festzustellen. Um die Konsequenzen einer Erhöhung von UV-B auf Kulturpflanzenbestände zu bestimmen, wurde die Empfindlichkeit unterschiedlicher Arten wie Gerste, Weizen, Hafer, Klee, Wiesenlieschgras, Wiesenschwingel, Rohrschwingel und Kartoffel in Jokioinen, Finnland, untersucht. Das Experiment wurde im Felde durchgeführt unter natürlichen Lichtbedingungen mit einer kontinuierlichen Zunahme von 30 % für UV-B. Sowohl eine Erhöhung der UV-B als auch die Kontrolle mit leicht erhöhten UV-B Strahlungen beeinflussten die Anzahl der Nebenwurzeln bei den Getreidepflanzen und die spezifische Blattfläche sowie den Gehalt an phenolischen Substanzen bei den Gräsern. Die Wirkungen variierten entsprechend der Pflanzenvarietät und der Anbauzeit. Allerdings wurden keine erkennbare Schädigungen noch Änderungen in der Biomasse und in der Ertragsproduktion bei einer der untersuchten Pflanzenbestände gefunden. Langzeitwirkungen auf die genetische bedingte Stabilität und Keimung der Kulturpflanzen sollte weiterhin untersucht werden. [source] Assessment of Dental Caries Predictors in a Seven-year Longitudinal StudyJOURNAL OF PUBLIC HEALTH DENTISTRY, Issue 3 2006Elaine Pereira da Silva Tagliaferro DDS Abstract Objective: To identify, in a group of 6,8-year-old schoolchildren, risk factors for dental caries increment in permanent dentition. Methods: Two hundred and six children from three different schools in Piracicaba, Brazil, were examined at baseline and after 7 years by the same two calibrated dentists. Data on dental caries (dmfs, DMFS, presence of initial lesions), fluorosis, oral hygiene and presence of sealant were collected at the clinical examination that was performed in an outdoor setting, under natural light, using a dental mirror and probe following the WHO recommendations. Information on socioeconomic level, fluoride usage, dental service utilization, dietary and oral hygiene habits was also obtained at baseline in a semi-structured questionnaire sent to the parents. The dependent variable was the 7-year DMFS increment. A univariate analysis was performed to test the association of independent variables in caries increment. Then a logistic regression model was used to estimate the adjusted Odds Ratio for caries increment. Results: Clinical (dmfs, DMFS) and non-clinical variables (daily toothbrushing, use of preventive topical methods, parents' educational level) were entered in the multiple logistic regression analysis. The prediction model included the clinical and socioeconomic variables, DMFS, dmfs and mother's educational level. The best caries predictor was the dmfs variable. Conclusion: Caries experience and mother's educational level were predictors of caries increment in permanent dentition. [source] Enamel Fluorosis Prevalence after a 7-year Interruption in Water Fluoridation in Jaú, São Paulo, BrazilJOURNAL OF PUBLIC HEALTH DENTISTRY, Issue 4 2004Manila A. R. Buzalaf DDS ABSTRACT Objectives: This paper analyzes the impact of a 7-year interruption in water fluoridation on the prevalence of enamel fluorosis in Jaú, state of São Paulo, Brazil. Methods: Fluorosis prevalence (TF index) was evaluated in permanent maxillary central incisors of children (9,14 years old) that were 36 (n=81; cohort -36), 27 (n=81; cohort -27), and 18 months old (± 1 month; n=89; cohort,18) in October 1991, when the break started, and 18 months old (± 1 month; n=70; cohort 18) after that date. Children brushed their teeth prior to examination, which was conducted under natural light by three calibrated examiners (agreement 87.8,93.8%, kappa 0.72,0.85). Results: The fluorosis prevalence (TF,1) was 7.41 percent, 3.70 percent, 7.87 percent, and 18.57 percent, respectively, for cohorts -36, -27, -18, and 18. The difference between cohort 18 and the other groups was statistically significant (Kruskall-Wallis test, P=.05). Conclusions: These results suggest that the fluoridated water is not an important risk factor for enamel fluorosis, since the prevalence of enamel fluorosis was low in the cohorts -36, -27, and -18 when fluoridated water was used. [J Public Health Dent 2004;64(4):205,8]. [source] Knowing God by reason alone: what Vatican I never saidNEW BLACKFRIARS, Issue 1033 2010Fergus Kerr OP Abstract While the First Vatican Council (1869,70) decreed that for Catholics it is a dogma of faith that we can have certain knowledge of God by the natural light of reason it was only in the Anti-Modernist Oath (1910) that this knowledge was defined as rationally demonstrable by cosmological arguments. [source] Red to far-red ratio correction in plant growth chambers , growth responses and influence of thermal load on garden peaPHYSIOLOGIA PLANTARUM, Issue 2 2007Ian G. Cummings Plant growth chambers are commonly used to minimize environmental variation but the light sources used vary considerably from natural light and from each other. Incandescent globes are often used to add more far-red light, with the aim of producing a more natural red to far-red ratio (R:FR), but also add to thermal load. High-intensity discharge lamps are often used to produce higher irradiances, more akin to natural light, but the thermal implications are rarely considered because air temperature is controlled. This paper examines the spectral properties and thermal implications of growth chamber light sources and takes a whole-plant physiology approach, by examining growth responses of a photoperiodic pea line (Pisum sativum L. cv. Torsdag) in the same growth chamber type under different light sources , in essence using plants to study the controlled environments rather than vice-versa. High R:FR delayed flowering and inhibited internode extension in pea. However, the addition of far-red-rich incandescent globes in the proportions provided in the growth chambers (400,500 W) did little to reduce R:FR, did not induce earlier flowering and actually further inhibited internode length. Leaflet size and yield were significantly reduced. While air temperature was maintained at 20°C in all experiments, radiant temperature was significantly higher under high irradiance and/or with incandescent added, and soil temperatures were elevated. Growth responses under these lights were similar to the effect caused by elevating the air temperature. An alternative method of controlling R:FR, without thermal load implications, using light-emitting diodes is described. [source] Seasonally changing metabolism in Atlantic salmon (Salmo salar L.) II ,, -oxidation capacity and fatty acid composition in muscle tissues and plasma lipoproteinsAQUACULTURE NUTRITION, Issue 5 2003U. Nordgarden Abstract With the aim of elucidating seasonally changing lipid metabolism in immature Atlantic salmon (Salmo salar L.) in sea water, one group was reared under simulated natural light, while one group was reared under continuous light. Fatty acid profile in plasma lipoproteins did not vary during the experiment, while , -oxidation capacity increased during spring, concurrent with decreasing temperatures. Simultaneously, the relative level of monounsaturated fatty acids (MUFA) in muscle tissue decreased (42,36%). Muscle levels of saturated fatty acids were low during early spring (19%), but then increased slowly, and muscle levels of polyunsaturated fatty acids increased during spring (from 36% to 39%). It is suggested that increased spring growth and the concomitant energy demand was met by increased lipid oxidation, where MUFA were preferred as energy substrate. [source] | |||||||||||||