371 research outputs found
Occlusal outcomes in combined orthodontic and orthognathic treatment
OBJECTIVE: To investigate the treatment outcome in terms of the malocclusion features and the changes in the occlusion of patients undergoing orthodontic/orthognathic treatment using the Peer Assessment Rating (PAR) and the Index of Complexity, Outcome and Need (ICON) and to test the application of the Index of Orthognathic Functional Treatment Need (IOFTN) on this sample as a measure of orthognathic pre-treatment need.
DESIGN: Retrospective longitudinal cohort study.
SETTING: The orthodontic department at the Eastman Dental Hospital.
MATERIAL AND METHODS: The study models of a sample of 100 orthodontic/orthognathic patients who were treated at the Eastman Dental Hospital were measured using the PAR index and ICON at three stages: pre-treatment, pre-surgery and at debond. Treatment need was assessed by measuring IOTN and IOFTN using start study models.
RESULTS: 99% of the sample showed an improvement in PAR score, with 82% of the sample being greatly improved. ICON showed that 95% of the sample had an improvement of different degrees with 5% being not improved or worse. The IOFTN qualified 97% of the patients for orthognathic treatment when used retrospectively on the sample while the DHC of IOTN qualified the whole sample for orthodontic treatment.
CONCLUSIONS: Orthodontic/orthognathic treatment showed improved and acceptable overall results. The PAR index and ICON were valid measures to investigate the outcome of orthognathic treatment. IOFTN proved to be a useful tool in determining and prioritizing orthognathic treatment based purely on functional need
Bath Adsorption Study of Methylene Blue Dye Onto Sunflower Seeds Husks Activated Carbon
Mesoporous activated carbon prepared from sunflower seeds husks (SSH) using physiochemical activation (potassium hydroxide treatment and carbon dioxide gasification). The optimum conditions for preparing activated carbon from (SSH) were found to be activation temperature of 500 oC, activation time of 1.0 h and chemical impregnation ratio of 1:1. The adsorptions of methylene blue (MB) onto sunflower seed husks activated carbon (SSHAC) were studied with respect to initial MB concentration. The experimental data were analyzed by the Langmuir isotherm, the Freundlich isotherm and the Temkin isotherm. Equilibrium data fitted well with the Langmuir model with maximum adsorption capacity of 410 mg/g at 30 oC for MB concentration range of 50-300 mg/L. Desorption-adsorption studies for the spent SSHAC (saturated with MB) using ethanol as solvent showed that regeneration efficiency around 85%. The results indicated that the SSHAC is very effective for the adsorption of MB from aqueous solutions and can be regenerate to use for more than two adsorption cycles
Assessment Of Upper Cretaceous Strata For Offshore CO2 Storage: Southeastern United States
This is the first assessment of Upper Cretaceous strata for offshore CO2 storage resources in the southeastern United States outer continental shelf. This research focuses on Upper Cretaceous geological units using legacy industry 2-D seismic reflection and well data. It provides an integrated description and reliable subsurface evaluation of Upper Cretaceous potential storage reservoirs. In addition, it provides a detailed evaluation on how rock porosities and permeabilities are distributed across the Upper Cretaceous strata restricted to the South Georgia Embayment (SGE). Structure and thickness (isochore) maps were generated for the main potential reservoirs and seals on a regional and local scale. This assessment is the first application of multiple seismic inversion techniques in SEG. It provides a reliable and reputable workflow of Model-Based inversion which gives an improved image to discriminate lithology and predict porosity. This workflow can be applied to future CO2 storage resource assessment studies elsewhere. The inversion results indicated that distinct porosity and permeability regimes are present and distributed in Upper Cretaceous within the SGE. The impedance and porosity relationships show well founded and reliable correlation. This relationship reveals low impedance coincident to the high porosity intervals which are proposed as potential reservoir intervals for CO2 storage. In addition, it shows that the Upper Cretaceous strata have two main potential reservoirs in the lower part. These are overlain by a thick impermeable interval, mostly shale which has high impedance, low porosity, and low permeability, which extends within the SGE. Since porosity distribution is estimated using different methods, it follows the trends of seismic signature and structures of Upper Cretaceous strata. The extracted values of porosity, ranging from 15 to 36 %, and permeability, ranging from 1 to 100 mD, are close to the measured values from the well core data at the Upper Cretaceous strata interval.
Five reservoirs and seals were recognized as potential storage units. Two reservoirs are particularly considered as the main CO2 storage units with quality and integrity capable to meet the CO2 storage requirements by the U.S. Department of Energy. They consist of limestone deposits with significant interbedded sandstones, shales and dolomites, and are sealed by thick shales interbedded with limestone. The porosity ranges from 20 to 30 % and the permeability ranges from 1 to 447 mD. Regional CO2 storage capacity is estimated to be approximately 32 GT in Upper Cretaceous units. The local storage capacity for the two significant reservoirs in the SGE contribute ~ 9 GT of that amount
A Radio Determination of the Time of the New Moon
The detection of the New Moon at sunset is of importance to communities based
on the lunar calendar. This is traditionally undertaken with visual
observations. We propose a radio method which allows a higher visibility of the
Moon relative to the Sun and consequently gives us the ability to detect the
Moon much closer to the Sun than is the case of visual observation. We first
compare the relative brightness of the Moon and Sun over a range of possible
frequencies and find the range 5--100\,GHz to be suitable. The next
consideration is the atmospheric absorption/emission due to water vapour and
oxygen as a function of frequency. This is particularly important since the
relevant observations are near the horizon. We show that a frequency of GHz is optimal for this programme. We have designed and constructed a
telescope with a FWHM resolution of 0.6 and low sidelobes to
demonstrate the potential of this approach. At the time of the 21 May 2012 New
Moon the Sun/Moon brightness temperature ratio was in agreement
with predictions from the literature when combined with the observed sunspot
numbers for the day. The Moon would have been readily detectable at from the Sun. Our observations at 16\,hr\,36\,min UT indicated that
the Moon would have been at closest approach to the Sun 16\,hr\,25\,min
earlier; this was the annular solar eclipse of 00\,hr\,00\,min\,UT on 21 May
2012.Comment: 11 pages, 15 figures, accepted for publication in MNRA
Four-Wave Mixing in Weyl Semimetals
Weyl semimetals (WSMs) have unusual optical responses originating from unique topological
properties of their bulk and surface electron states. Their third-order optical nonlinearity is expected to be very strong, especially at long wavelengths, due to linear dispersion and high Fermi velocity of three-dimensional Weyl fermions. Here we derive the third-order nonlinear optical conductivity of WSMs in the long-wavelength limit and calculate the intensity of the nonlinear four-wave mixing signal as it is transmitted through the WSM film or propagates away from the surface of the material in the reflection geometry. All results are analytic and show the scaling of the signal intensity with variation of all relevant parameters. The nonlinear generation efficiency turns out to be surprisingly high for a lossy material, of the order of several mW per WĀ³ of the incident pump power. Optimal conditions for maximizing the nonlinear signal are realized in the vicinity of bulk plasma resonance. This indicates that ultrathin WSM films of the order of skin depth in thickness could find applications in compact optoelectronic devices
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The Effect of Degree of Composite Action on RWS Connections Subject to Cyclic Loading
Concerns have been raised over the presence of concrete slab and resulting composite action in jeopardising the concept of strong column and weak beam seismic design. This comprehensive finite element analysis (FEA) aims to study the effect of the degree of composite action and other two parameters; namely, size and location of the web opening, on the performance of steel-concrete composite extended end-plate RWS connections subjected to cyclic loading. It is apparent that the degree of composite action of RWS connections is an important factor in their seismic-resistant design. In particular, the low degree of composite action in RWS connections can result in the mitigation of the bottom flange fracture damage and the crushing and cracking of the concrete slab. It is concluded that extended end-plate RWS connections can be used in retrofitting existing and in new buildings in seismic areas
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Water and Soil Management Practices to Enhance Plant Growth, Berry Development, and Fruit Quality of Northern Highbush Blueberry (Vaccinium corymbosum L.)
Drought and mandatory water restrictions are limiting the availability of irrigation water in many important blueberry growing regions and new strategies are needed to maintain yield and fruit quality with less water. Three potential options for reducing water use, including deficit irrigation, irrigation cut-offs, and crop thinning, were evaluated for 2 years in a mature planting of northern highbush blueberry (Vaccinium corymbosum L. āElliottā). Treatments consisted of no thinning and 50% crop removal in combination with either full irrigation at 100% of estimated crop evapotranspiration (ETsubscript c]), deficit irrigation at 50% ET[subscript c] (applied for the entire growing season), or full irrigation with irrigation cut-off for 4ā6 weeks during early or late stages of fruit development. Stem water potential was similar with full and deficit irrigation but, regardless of crop thinning, declined by 0.5ā0.6 MPa when irrigation was cut-off early and by > 2.0 MPa when irrigation was cut-off late. In one or both years, the fruiting season was advanced with either deficit irrigation or late cut-off, whereas cutting off irrigation early delayed the season. Yield was not affected by deficit irrigation in plants with a full crop load but was reduced by an average of 35% when irrigation was cut-off late each year. Cutting off irrigation early likewise reduced yield, but only in the second year when the plants were not thinned; however, early cut-off also reduced fruit soluble solids and berry weight by 7% to 24%compared to full irrigation. Cutting off irrigation late produced the smallest and firmest fruit with the highest soluble solids and total acidity among the treatments, as well as the slowest rate of fruit loss in cold storage. Deficit irrigation had the least effect on fruit quality and, based on these results, appears to be the most viable option for maintaining yield with less water (2.5 MLĀ·haā»Ā¹ less water per season).
A second study was conducted in a 7-year-old field of certified organic highbush blueberry. Two cultivars (āDukeā and āLibertyā) mulched with either porous polyethylene ground cover (āweed matā) or yard debris compost topped with sawdust (sawdust+compost) and each fertilized with either feather meal or fish emulsion were evaluated. One-year-old fruiting laterals were randomly-selected at three heights (top, middle, and bottom) on the east and west side of the plants. Bud, flower, and fruit development were monitored through fruit harvest. There was relatively little effect of mulch type or fertilizer source on the measured variables. Fruit harvest occurred ā8 d after the fruit were fully blue and ranged from 2-25 July 2012 and 26 June-3 July 2013 in āDukeā and from 1-20 Aug. 2012 and 17 July-7 Aug. 2013 in āLibertyā. Proportionally more fruit buds occurred on middle laterals than upper and lower laterals. The dates of bud swell and bud break were not affected by cultivar or lateral position. āDukeā and āLibertyā produced 6-8 and 7-9 flowers/bud, respectively. Fruit set was high in both cultivars, averaging ā95%. However, 13-18% and 29-38 % of the initial set fruit dropped in āDukeā and āLibertyā in late May to early June. Fruit ripening was more uniform within clusters in āDukeā than in āLibertyā, and average fruit size was similar among harvests in āDukeā but decreased by 25-40% between the first and last harvest in āLibertyā. Fruit matured 3ā5 d earlier on the east side of the canopy than on the west side. The results suggest that pruning proportionally more on the lower part of the canopy than on the upper part will result in larger fruit at harvest than uniform pruning throughout the bush.
The final study was conducted to determine the potential of applying micronized elemental sulfur (SĀ°) by chemigation through the drip system to reduce high soil pH in a new planting of āDukeā blueberry. The SĀ° was mixed with water and injected weekly for 2 months prior to planting, as well as 2 years after planting, atrates of 0, 50, 100 and 150 kgĀ·haā»Ā¹ per year, and was compared to the conventional practice of incorporating prilled SĀ° into the soil prior to planting (two applications of 750 kgĀ·haā»Ā¹ each). Chemigation quickly reduced soil pH (0-10 cm) within a month from 6.6 with no SĀ° to 6.1 with 50 kgĀ·ha-1 SĀ° and 5.8 with 100 or 150 kgĀ·haā»Ā¹ SĀ°. The change was short-term, however, and by May of the following year, soil pH averaged 6.7, 6.5, 6.2, and 6.1 with each increasing rate of SĀ° chemigation, respectively. The conventional treatment, in comparison, averaged 6.6 on the first date and 6.3 on the second date. In July of the following year, soil pH ranged from an average of 6.4 with no SĀ° to 6.2 with 150 kgĀ·haā»Ā¹ SĀ° and 5.5 with prilled SĀ°. Soil pH declined thereafter to as low as 5.9 with additional SĀ° chemigation and at lower depths (10-30 cm) was similar to the conventional treatment. None of the treatments had any effect on winter pruning weight in year 1 or on yield, berry weight, and plant dry weight in year 2. Chemigation with SĀ° can be used to quickly reduce soil pH following planting and, therefore, may be a useful practice to correct high pH problems in established blueberry fields. However, it was less effective and more time consuming than applying prilled SĀ° prior to planting
Patterns, Knowledge and Attitudes of Irrational Antibiotic Use in the Saudi Community
Background: Antibiotics are one of the most commonly sold drugs without prescription in the Eastern countries because there is no policy to regulate antibiotics use and they are available over the counter.Ā Irrational use of antibiotics leads to unwanted side effects, increase admissions, cost, and increase antimicrobial resistance.Ā Antimicrobial resistance on the other hand considered a global problem in the community as well as in hospitals.Ā This study thought to evaluate the current patterns of use, knowledge and attitudes of irrational use of antibiotics among Saudi population.Ā Uncovering related factors are important in order to intervene effectively. Methods: A convenience sample of 427 participants was interviewed from the community in a semi structured interview.Ā A descriptive comparative cross sectional design was used to investigate patterns, knowledge and attitudes of irrational antibiotic use.Ā The questionnaire included demographics, patterns, knowledge and attitudes of antibiotic use.Ā The questionnaire was developed by the investigator and was piloted and tested for validity and reliability. Results: Participants in this study were young, university graduates, 59% females, and 55% were married. Results showed inappropriate use of antibiotics for self and family throughout the year. Half of participants based their antibiotic use on pharmacist, friendās advice and previous use.Ā Majority does not read the antibioticsā instructions and are not aware of possible side effects, or their own allergy to such antibiotic.Ā In addition there was a general unsatisfactory level of knowledge regarding antibiotics use.Ā Women reported statistical significant higher level of knowledge then men.Ā Further, attitude toward antibiotic use wasnāt that instructive. Conclusion and Recommendations: As reflected from young age and highly educated sample in the current study, the low level of knowledge and inappropriate pattern regarding antibiotic use constitute a true problem in the community.Ā A number of implications flow from this study, education alone could not be enough to change behavior.Ā There is a basic need to address the attitudes and belief to get benefits of changing a pattern or behavior. To bridge the gap between knowledge and attitude toward antibiotic use, a culturally aware health education campaigns should reach all the Saudi community.Ā Further, establishing a medical policy to regulate antibiotic use is of great importance. Keywords: Antibiotic, Irrational, Pattern, Knowledge, Attitude
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