[Validity of self-perceived dental caries as a diagnostic test and associated factors in adults].

Science.gov (United States)

Haikal, Desirée Sant'Ana; Roberto, Luana Leal; Martins, Andréa Maria Eleutério de Barros Lima; Paula, Alfredo Maurício Batista de; Ferreira, Efigênia Ferreira E

2017-08-21

This study aimed to analyze the validity of self-perceived dental caries and associated factors in a sample of 795 adults (35-44 years). The dependent variable was self-perceived dental caries, and the independent variables were combined in blocks. Three logistic models were performed: (1) all adults; (2) adults with a formal diagnosis of caries; and (3) adults without such caries. Self-perceived dental caries showed 77.7% sensitivity, 58% specificity, 65% accuracy, 52% positive predictive value, and 81% negative predictive value. In Model 1, self-perceived dental caries was associated with time of use of dental services, access to information, flossing, formal diagnosis of caries, self-perceived need for treatment, toothache, and dissatisfaction with oral health and general health. In Model 2, self-perceived dental caries was associated with time of use of dental services, self-perceived need for treatment, and dissatisfaction with oral health and general health. In Model 3, self-perceived dental caries was associated with time of use of dental services, access to information, flossing, self-perceived need for treatment, and dissatisfaction with oral health. Self-perceived dental caries showed limited utility as a diagnostic method.

Oral Health: Brush Up on Dental Care Basics

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... Mayo Clinic Staff Your smile depends on simple dental care habits, such as brushing and flossing. But are you using the right techniques? Follow these steps to protect your oral health. Oral health begins with clean teeth. Keeping the area where your teeth meet your ...

Influence of storage duration and processing on chromatic attributes and flavonoid content of moxa floss.

Science.gov (United States)

Lim, Min Yee; Huang, Jian; Zhao, Bai-xiao; Zou, Hui-qin; Yan, Yong-hong

2016-01-01

Moxibustion is an important traditional Chinese medicine therapy using heat from ignited moxa floss for disease treatment. The purpose of the present study is to establish a reproducible method to assess the color of moxa floss, discriminate the samples based on chromatic coordinates and explore the relationship between chromatic coordinates and total flavonoid content (TFC). Moxa floss samples of different storage years and production ratios were obtained from a moxa production factory in Henan Province, China. Chromatic coordinates (L*, a* and b*) were analyzed with an ultraviolet-visible spectrophotometer and the chroma (C*) and hue angle (h°) values were calculated. TFC was determined by a colorimetric method. Data were analyzed with correlation, principal component analysis (PCA). Significant differences in the chromatic values and TFC were observed among samples of different storage years and production ratios. Samples of higher production ratio displayed higher chromatic characteristics and lower TFC. Samples of longer storage years contained higher TFC. Preliminary separation of moxa floss production ratio was obtained by means of color feature maps developed using L*-a* or L*-b* as coordinates. PCA allowed the separation of the samples from their storage years and production ratios based on their chromatic characteristics and TFC. The use of a colorimetric technique and CIELAB coordinates coupled with chemometrics can be practical and objective for discriminating moxa floss of different storage years and production ratios. The development of color feature maps could be used as a model for classifying the color grading of moxa floss.

[Oral hygiene habits and use of dental services among teenage students in a city in southern Brazil].

Science.gov (United States)

Freddo, Silvia Letícia; Aerts, Denise Rangel Ganzo de Castro; Abegg, Claídes; Davoglio, Rosane; Vieira, Patrícia Conzatti; Monteiro, Lisiane

2008-09-01

This study evaluated oral hygiene habits and use of dental services among teenage students, and analyzed their association with sociodemographic factors and life styles. This cross-sectional study included a representative sample of 1,170 seventh-graders from municipal public schools of Gravataí, Rio Grande do Sul State, Brazil. The Cox regression model for univariate analysis, modified for cross-sectional studies, was used to analyze the association between variables. Of the adolescents included in the study, 77.8% brushed their teeth three or more times a day, 31.9% flossed daily, 68.9% visited the dentist regularly, and 50% visited the dentist for dental treatment. Tooth brushing was more frequent among female adolescents. Lower socioeconomic status was associated with a lower frequency of daily flossing, fewer annual dental visits, and a greater prevalence of dental treatment visits. Similar results were found for adolescents with a sedentary lifestyle or that had tried smoking. The consumption of candy was associated with lower frequency of annual dental visits, and the consumption of soft drinks, with greater frequency of treatment visits. A healthy life style was associated with better oral hygiene habits and more frequent dental visits.

Politické myšlení Karla Flosse

Czech Academy of Sciences Publication Activity Database

Černý, Jan

2016-01-01

Roč. 46, č. 95/96 (2016), s. 312-317 ISSN 0323-2220 R&D Projects: GA ČR(CZ) GA16-23046S Institutional support: RVO:67985955 Keywords : Karel Floss * political thought * Platonism * Christianity Subject RIV: AA - Philosophy ; Religion OBOR OECD: Philosophy, History and Philosophy of science and technology

Mechanical properties of carving wax with various Ca-bentolite filter composition

Directory of Open Access Journals (Sweden)

Widjijono Widjijono

2009-09-01

Full Text Available Background: The carving wax is used as a medium in dental anatomy study. This wax composes of many waxes and sometimes a filler is added. Carving wax is not sold in Indonesian market. Whereas the gradients of carving wax such as beeswax, paraffin and bentonite are abundant in Indonesia. Based on that fact, to make high quality and standard,the exact composition if this carving wax should be known. Purpose: The aim of this study was to investigate the effect of carving wax composition with Ca-bentonite filler on the melting point, hardness, and thermal expansion. Methods: Five carving wax compositions were made with paraffin, Ca-bentonite, carnauba wax, and beeswax in ratio (% weight: 50:20:25:5 (KI, 55:15:25:5 (KII, 60:10:25:5 (KIII, 65:5:25:5 (KIV, 70:0:25:5(KV. All components were melted, then poured into the melting point, hardness, and thermal expansion moulds (n = 5. Three carving wax properties were tested: melting point by melting point apparatus; hardness by penetrometer; thermal expansion by digital sliding caliper. The data were analyzed statistically using One-Way ANOVA and LSD0.05. Result: The Ca-bentonite addition influenced the melting point and thermal expansion of carving wax with significant differences between KI and other groups (p < 0.05. Ca-bentonite addition influenced the carving wax hardness and the mean differences among the groups were significant (p < 0.05. Conclusion: Ca-bentonite filler addition on the composition of carving wax influenced the physical and mechanical properties. The carving wax with high Ca-bentonite concentration had high melting point and hardness, but low thermal expansion.

Influence of Nerve Flossing Technique on acute sciatica and hip ...

African Journals Online (AJOL)

MJP

2015-08-21

Aug 21, 2015 ... experimental design, involving 32 participants from two hospitals in Lagos state. Nigeria, with ... excursion occurs during nerve flossing exercise initiated from ... Assessment ..... evacuation of intraneural edema which might be.

Use of dental clinics and oral hygiene practices in the Kingdom of Saudi Arabia, 2013.

Science.gov (United States)

El Bcheraoui, Charbel; Tuffaha, Marwa; Daoud, Farah; Kravitz, Hannah; AlMazroa, Mohammad A; Al Saeedi, Mohammad; Memish, Ziad A; Basulaiman, Mohammed; Al Rabeeah, Abdullah A; Mokdad, Ali H

2016-04-01

We conducted a large household survey in 2013 to determine the current status of oral health practices and use of oral health services in the Kingdom of Saudi Arabia (KSA). The Saudi Health Information Survey is a national multistage survey of individuals ≥ 15 years of age. We used a backward elimination multivariate logistic regression model to measure the association between having been to a dental clinic during the last year, and sex, age, marital status, education, time since last routine medical examination, history of diagnosis with a cardiovascular chronic condition, brushing or flossing teeth and use of Miswak (a chewing stick). Between April and June 2013, 10,735 participants completed the survey (89.4% of the households contacted). An estimated 1.5 million (11.5%) and 6.3 million (48.6%) Saudi Arabian people, ≥ 15 years of age, had visited a dental clinic for a routine check-up and for a complaint during the last year, respectively. In total, 16.3%, 85.0% and 52% of Saudi Arabian people never brush their teeth, never floss their teeth or never use Miswak, respectively. The probability of visiting a dental clinic increased with education, among individuals who brushed or flossed their teeth and who used Miswak. Oral hygiene practices are not common among Saudi Arabian people, and use of health care for prevention of oral disease is limited. Hence, the need for oral health promotion is pressing. The KSA Ministry of Health should develop and implement programmes, through its primary health clinics, to increase the awareness of the importance of good oral health. © 2016 The Authors. International Dental Journal published by John Wiley & Sons Ltd on behalf of World Dental Federation.

21 CFR 872.4565 - Dental hand instrument.

Science.gov (United States)

2010-04-01

... chisel, endodontic broach, dental wax carver, endodontic pulp canal file, hand instrument for calculus... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Dental hand instrument. 872.4565 Section 872.4565...) MEDICAL DEVICES DENTAL DEVICES Surgical Devices § 872.4565 Dental hand instrument. (a) Identification. A...

Oral hygiene practices and dental service utilization among pregnant women.

Science.gov (United States)

Boggess, Kim A; Urlaub, Diana M; Massey, Katie E; Moos, Merry-K; Matheson, Matthew B; Lorenz, Carol

2010-05-01

Daily oral hygiene and regular dental visits are important components of oral health care. The authors' objective in this study was to examine women's oral hygiene practices and use of dental services during pregnancy. The authors developed a written oral health questionnaire and administered it to 599 pregnant women. They collected demographic information, as well as data on oral hygiene practices and use of dental services during pregnancy. They used chi2 and multivariable logistic regression models to assess associations between oral hygiene practice and dental service use during pregnancy and to identify maternal predictor variables. Of the 599 participants, 83 percent (n=497) reported brushing once or twice per day. Twenty-four percent (n=141) reported flossing at least once daily; Hispanic women were more likely to floss than were white or African American women (28 percent [52 of 183] versus 22 percent [54 of 248] versus 19 percent [23 of 121], respectively, Pdental care during pregnancy. Hispanic women were significantly less likely than were black or white women to receive routine dental care during pregnancy (13 percent versus 21 percent versus 36 percent, respectively, Pdental care when not pregnant were significantly associated with lack of routine dental care during pregnancy (adjusted odds ratios, 95 percent confidence intervals: 2.56 [1.33-4.92]; 2.19 [1.11-4.29]; 2.02 [1.12-3.65]; 1.86 [1.13-3.07]; and 4.35 [2.5-7.69], respectively). A woman's lack of receiving routine dental care when not pregnant was the most significant predictor of lack of receiving dental care during pregnancy. Racial, ethnic and economic disparities related to oral hygiene practices and dental service utilization during pregnancy exist. Medical and dental care providers who treat women of reproductive age and pregnant women need to develop policy strategies to address this population's access barriers to, and use of, dental care services.

Evaluation of silk-floss fiber and dog fur as sorbent materials for the petroleum sector

Energy Technology Data Exchange (ETDEWEB)

Santos, Lucas P. dos [Universidade Federal do Parana (PGMec/UFPR), Curitiba, PR (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica; Dubiella, Juliana [Universidade Federal do Parana (DEMEC/UFPR), Curitiba, PR (Brazil). Dept. de Engenharia Mecanica. Programa Institucional de Bolsas de Iniciacao Cientifica; Perotta, Larissa [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Programa Interdisciplinar em Engenharia de Petroleo e Gas Natural; Satyanarayana, Kestur G. [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept. de Quimica; Flores-Sahagun, Thais Sydenstricker [Universidade Federal do Parana (DEMEC/UFPR), Curitiba, PR (Brazil). Dept. de Engenharia Mecanica

2009-07-01

In this study silk-floss and dog fur were tested as sorbent materials for oils and the results were compared with peat, a commercial sorbent. Sorption tests were carried out in dry and aqueous systems, with and without stirring for different periods of time (5-1440 min). Density, hydrophobicity, buoyancy and water uptake by the fibers of the impregnated sorbents have been determined. The use of silk-floss and dog fur was also tested in columns to purify water containing toluene, benzene, motor oil or sunflower oil. Breakthrough curves during 120 min were drawn for each material with the samples (oily water or water containing benzene or toluene) and were analyzed by ultraviolet spectroscopy. It was concluded that the silk-floss is the best sorbent material (65.3 g oil/g sorbent) followed by the dog fur (34.6 g oil/g sorbent) and peat (19.5 g oil/g sorbent), for sorption time of 1 h in dynamic condition. The efficiency of the pollutant removal from water with the use of adsorption columns was high for both materials although the use of dog fur was preferable because of the slight superiority in efficiency compared to silk-floss and also, due to the easier packing of the dog fur in the column. (author)

Ear wax

Science.gov (United States)

See your provider if your ears are blocked with wax and you are unable to remove the wax. Also call if you have an ear wax blockage and you develop new symptoms, such as: Drainage from the ear Ear pain Fever Hearing loss that continues after you clean the wax

Usefulness of a traction method using dental floss and a hemoclip for gastric endoscopic submucosal dissection: a propensity score matching analysis (with videos).

Science.gov (United States)

Suzuki, Sho; Gotoda, Takuji; Kobayashi, Yoshiyuki; Kono, Shin; Iwatsuka, Kunio; Yagi-Kuwata, Naoko; Kusano, Chika; Fukuzawa, Masakatsu; Moriyasu, Fuminori

2016-02-01

Although endoscopic submucosal dissection (ESD) is a significant advancement in therapeutic endoscopy, it is a complicated technique and requires considerable expertise. In this exploratory study, we evaluated the efficacy of a simple traction method that uses dental floss and a hemoclip (DFC) and was developed to overcome the technical difficulties of ESD. In total, 238 early gastric cancers treated by ESD between May 2012 and December 2014 at Tokyo Medical University were retrospectively reviewed. Lesions treated by conventional ESD (n = 185) and by ESD with DFC (ESD-DFC) (n = 53) were compared. Multivariable analyses and propensity score matching were used to compensate for the differences in age, sex, resected specimen size, lesion location, lesion position, presence of ulceration, and operator level. The procedure time, rate of en bloc and complete resection, and rates of adverse events were evaluated between the 2 groups. Propensity score matching analysis created 43 matched pairs. Adjusted comparisons between ESD-DFC and conventional ESD showed similar treatment outcomes (en bloc resection rate: 97.7% vs 100%, P = .315; complete resection rate: 90.7% vs 95.3%, P = .397; perforation during ESD rate: 2.3% vs 2.3%, P = 1.000; post-ESD bleeding rate: 4.7% vs 4.7%, P = 1.000) but a significantly shorter procedure time for ESD-DFC (82.2 ± 79.5 minutes vs 118.2 ± 71.6 minutes, P = .002). ESD-DFC facilitated rapid ESD with good visualization and traction while ensuring high curability and safety. Copyright © 2016 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

A brief intervention changing oral self-care, self-efficacy, and self-monitoring.

Science.gov (United States)

Schwarzer, Ralf; Antoniuk, Agata; Gholami, Maryam

2015-02-01

The roles of self-efficacy and self-monitoring as proximal predictors of dental flossing frequency are studied in the context of an oral health intervention. A study among 287 university students, aged 19 to 26 years, compared an intervention group that received a brief self-regulatory treatment, with a passive and an active control group. Dental flossing, self-efficacy, and self-monitoring were assessed at baseline and 3 weeks later. The intervention led to an increase in dental flossing regardless of experimental condition. However, treatment-specific gains were documented for self-efficacy and self-monitoring. Moreover, changes in the latter two served as mediators in a path model, linking the intervention with subsequent dental flossing and yielding significant indirect effects. Self-efficacy and self-monitoring play a mediating role in facilitating dental flossing. Interventions that aim at an improvement in oral self-care should consider using these constructs. Statement of contribution What is already known on this subject? The adoption and maintenance of oral self-care can be facilitated by a number of social-cognitive variables. Interventions that include planning, action control, or self-efficacy components have been shown to improve dental flossing. In one recent study on flossing in adolescent girls, planning intervention effects were mediated by self-efficacy. What does this study add? Self-monitoring is associated with better oral self-care. A 10-min intervention improves self-efficacy and self-monitoring. Self-efficacy and self-monitoring operate as mediators between treatment and flossing. © 2014 The British Psychological Society.

Accuracy of Digitally Fabricated Wax Denture Bases and Conventional Completed Complete Dentures

Directory of Open Access Journals (Sweden)

Bogna Stawarczyk

2017-12-01

Full Text Available The purpose of this investigation was to analyze the accuracy of digitally fabricated wax trial dentures and conventionally finalized complete dentures in comparison to a surface tessellation language (STL-dataset. A generated data set for the denture bases and the tooth sockets was used, converted into STL-format, and saved as reference. Five mandibular and 5 maxillary denture bases were milled from wax blanks and denture teeth were waxed into their tooth sockets. Each complete denture was checked on fit, waxed onto the dental cast, and digitized using an optical laboratory scanning device. The complete dentures were completed conventionally using the injection method, finished, and scanned. The resulting STL-datasets were exported into the three-dimensional (3D software GOM Inspect. Each of the 5 mandibular and 5 maxillary complete dentures was aligned with the STL- and the wax trial denture dataset. Alignment was performed based on a best-fit algorithm. A three-dimensional analysis of the spatial divergences in x-, y- and z-axes was performed by the 3D software and visualized in a color-coded illustration. The mean positive and negative deviations between the datasets were calculated automatically. In a direct comparison between maxillary wax trial dentures and complete dentures, complete dentures showed higher deviations from the STL-dataset than the wax trial dentures. The deviations occurred in the area of the teeth as well as in the distal area of the denture bases. In contrast, the highest deviations in both the mandibular wax trial dentures and the mandibular complete dentures were observed in the distal area. The complete dentures showed higher deviations on the occlusal surfaces of the teeth compared to the wax dentures. Computer-aided design/computer-aided manufacturing (CAD/CAM-fabricated wax dentures exhibited fewer deviations from the STL-reference than the complete dentures. The deviations were significantly greater in the

Factors associated with oral hygiene practices among adults with systemic sclerosis.

Science.gov (United States)

Yuen, H K; Hant, F N; Hatfield, C; Summerlin, L M; Smith, E A; Silver, R M

2014-08-01

To identify factors associated with oral hygiene practices in adults with systemic sclerosis (SSc). In this cross-sectional study, 178 dentate adults with SSc received an oral examination which included measurement of oral aperture, assessment of manual dexterity to perform oral hygiene, as well as completion of the Center of Epidemiological Studies Depression (CES-D) Scale and an oral health-related questionnaire. Multivariable logistic regression modelling showed male, minority and high CES-D scores (i.e. clinically significant symptoms of depression) were associated with less likelihood of participants brushing teeth at least twice daily, but the presence of self-reported dry mouth symptoms increased the likelihood of toothbrushing. Having a dental visit in the past 12 months and use of an adapted flossing or interdental cleaning device were significantly associated with daily dental flossing; however, having difficulty flossing teeth reduced the likelihood of daily flossing. Overall, demographic variables were strongly associated with toothbrushing frequency, whereas flossing self-efficacy and barriers were strongly associated with dental flossing frequency in adults with SSc. The results suggest that dental health professionals should take mental health into consideration when educating patients with SSc to improve their oral hygiene and consider making referrals for patients exhibiting suspected clinically significant depressive symptoms to mental health professionals for further evaluation and treatment. In addition, an appropriate adapted flossing or interdental cleaning device should be recommended to increase dental flossing practices in this patient population. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Geometrical effects of conventional and digital prosthodontic planning wax-ups on lateral occlusal contact number, contact area, and steepness.

Science.gov (United States)

Abduo, Jaafar

2017-01-01

This study evaluated and compared the effect of conventional and digital wax-ups on three lateral occlusion variables: contact number, contact area, and steepness. Dental casts of 10 patients with Angle Class I relationship were included in the study. All patients required fixed prosthodontic treatment that would affect lateral occlusion. The casts of all patients received conventional and digital wax-ups. For pretreatment, conventional wax-up, and digital wax-up casts, contact number, contact area, and occlusion steepness were measured at four lateral positions, that is, at excursions of 0.5, 1.0, 2.0, and 3.0 mm from maximal intercuspation. Lateral occlusion scheme variables were affected by use of diagnostic wax-ups. For all types of casts, contact number decreased as excursion increased. The two types of wax-ups had similar contact number patterns, and contact number was significantly greater for these casts than for pretreatment casts in the earlier stages of excursion. Similarly, contact area gradually decreased with increasing excursion in the pretreatment and conventional and digital wax-up casts. There was only a minimal decrease in occlusion steepness as excursion increased. However, lateral occlusion was generally steeper for digital wax-up casts.

Illness perceptions amongst individuals with dental caries.

Science.gov (United States)

Mafla, A C; Villalobos-Galvis, F H; Heft, M W

2018-03-01

To assess individuals' perception of dental caries, in order to explain how illness representations might influence their coping with the disease. Cross-sectional questionnaire study. 520 consecutive patients (aged ≥18 years) of the General Dentistry Clinic at Universidad Cooperativa de Colombia, Pasto, Colombia who had experienced dental caries. Illness perception of dental caries was assessed using the Illness Perception Questionnaire Revised (IPQ-R). The most frequent self-reported symptoms associated with dental caries were "toothache" (56.2%), "tooth sensitivity" (53.8%) and "mild to sharp pain when eating or drinking" (51.2%). The dimensions of illness perception were related to socio-economic status (SES). Symptoms of "loose or separating teeth" and "pus in your tooth" were associated with dental caries by low SES participants, while "bleeding while brushing, flossing or eating hard food" and "mild to sharp pain when eating or drinking something sweet, hot or cold" were related more to higher SES. Perceptions of caries were related to socioeconomic status. Interventions to promote health literacy in order to improve the capacity to obtain, process and understand basic oral health information could increase an early detection of caries. Copyright© 2018 Dennis Barber Ltd.

Understanding the distribution of natural wax in starch-wax films using synchrotron-based FTIR (S-FTIR).

Science.gov (United States)

Muscat, Delina; Tobin, Mark J; Guo, Qipeng; Adhikari, Benu

2014-02-15

High amylose starch-glycerol (HAG) films were produced incorporating beeswax, candelilla wax and carnauba wax in the presence and absence of Tween-80 in order to determine the distribution of wax in the films during the film formation process. The distribution of these waxes within the film was studied using Synchrotron based Fourier Transform Infrared Spectroscopy (S-FTIR) which provided 2D mapping along the thickness of the film. The incorporation of 5% and 10% wax in HAG films produced randomly distributed wax or wax-rich domains, respectively, within these films. Consequently, the addition of these waxes to HAG increased the surface roughness and hydrophobicity of these films. The addition of Tween-80 caused variations in wax-rich bands within the films. The HAG+carnauba wax+Tween-80 films exhibited domed wax-rich domains displayed with high integrated CH2 absorption value at the interior of the films, rougher surface and higher contact angle values than the other films. The S-FTIR 2D images indicated that the distribution of wax in starch-wax films correlated with the roughness and hydrophobicity of the starch-wax films. Copyright © 2013 Elsevier Ltd. All rights reserved.

Physical properties of beeswax, sunflower wax, and candelilla wax mixtures and organogels

Science.gov (United States)

There is increased interest in natural waxes as alternatives to partially hydrogenated oils and saturated fats as oil structuring agents. Using relatively low concentrations (0.5-5%), natural waxes are able to form crystalline networks, or organogels, which bind liquid oil. Each natural wax is uniqu...

21 CFR 184.1978 - Carnauba wax.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Carnauba wax. 184.1978 Section 184.1978 Food and... Substances Affirmed as GRAS § 184.1978 Carnauba wax. (a) Carnauba wax (CAS Reg. No. 008-015-869) is obtained from the leaves and buds of the Brazilian wax palm Copernicia cerifera Martius. The wax is hard...

Student performance in a flipped classroom dental anatomy course.

Science.gov (United States)

Chutinan, S; Riedy, C A; Park, S E

2017-11-09

The purpose of this study was to assess dental student learning in a dental anatomy module between traditional lecture and flipped classroom cohorts. Two cohorts of predoctoral dental students (N = 70 within each cohort) participated in a dental anatomy module within an Introduction to the Dental Patient (IDP) course ([traditional/lecture cohort: academic year (AY) 2012, 2013] and [flipped classroom cohort: AY 2014, 2015]). For the dental anatomy module, both cohorts were evaluated on pre-clinical tooth waxing exercises immediately after each of five lectures and tooth identification after all lectures were given. Additionally, the cohorts' performance on the overall IDP course examination was compared. The flipped classroom cohort had statistically significant higher waxing scores (dental anatomy module) than students in the traditional classroom. There was no statistically significant difference for tooth identification scores and the overall IDP course examination between the traditional vs flipped approach cohorts. This is due to the latter two assessments conducted at the end of the course gave all students enough time to review the lecture content prior to the assessment resulting in similar scores for both cohorts. The flipped classroom cohort promoted students' individual learning and resulted in improved students' performance on immediate evaluation but not on the end of the course evaluation. Redesign of courses to include a new pedagogical approach should be carefully implemented and evaluated for student's educational success. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Text2Floss: the feasibility and acceptability of a text messaging intervention to improve oral health behavior and knowledge.

Science.gov (United States)

Hashemian, Tony S; Kritz-Silverstein, Donna; Baker, Ryan

2015-01-01

Text messaging is useful for promoting numerous health-related behaviors. The Text2Floss Study examines the feasibility and utility of a 7-day text messaging intervention to improve oral health knowledge and behavior in mothers of young children. Mothers were recruited from a private practice and a community clinic. Of 156 mothers enrolled, 129 randomized into text (n = 60) and control groups (n = 69) completed the trial. Participants in the text group received text messages for 7 days, asking about flossing and presenting oral health information. Oral health behaviors and knowledge were surveyed pre- and post-intervention. At baseline, there were no differences between text and control group mothers in knowledge and behaviors (P > 0.10). Post-intervention, text group mothers flossed more (P = 0.01), had higher total (P = 0.0006) and specific (P Text messages were accepted and perceived as useful. Mothers receiving text messages improved their own oral health behaviors and knowledge as well as their behaviors regarding their children's oral health. Text messaging represents a viable method to improve oral health behaviors and knowledge. Its high acceptance may make it useful for preventing oral disease. © 2014 American Association of Public Health Dentistry.

Internal fit of three-unit fixed dental prostheses produced by computer-aided design/computer-aided manufacturing and the lost-wax metal casting technique assessed using the triple-scan protocol.

Science.gov (United States)

Dahl, Bjørn E; Dahl, Jon E; Rønold, Hans J

2018-02-01

Suboptimal adaptation of fixed dental prostheses (FDPs) can lead to technical and biological complications. It is unclear if the computer-aided design/computer-aided manufacturing (CAD/CAM) technique improves adaptation of FDPs compared with FDPs made using the lost-wax and metal casting technique. Three-unit FDPs were manufactured by CAD/CAM based on digital impression of a typodont model. The FDPs were made from one of five materials: pre-sintered zirconium dioxide; hot isostatic pressed zirconium dioxide; lithium disilicate glass-ceramic; milled cobalt-chromium; and laser-sintered cobalt-chromium. The FDPs made using the lost-wax and metal casting technique were used as reference. The fit of the FDPs was analysed using the triple-scan method. The fit was evaluated for both single abutments and three-unit FDPs. The average cement space varied between 50 μm and 300 μm. Insignificant differences in internal fit were observed between the CAD/CAM-manufactured FDPs, and none of the FPDs had cement spaces that were statistically significantly different from those of the reference FDP. For all FDPs, the cement space at a marginal band 0.5-1.0 mm from the preparation margin was less than 100 μm. The milled cobalt-chromium FDP had the closest fit. The cement space of FDPs produced using the CAD/CAM technique was similar to that of FDPs produced using the conventional lost-wax and metal casting technique. © 2017 Eur J Oral Sci.

Eldercare at Home: Dental Problems

Science.gov (United States)

... or make the handle longer by attaching a piece of wood or another toothbrush handle. Use a floss holder to make flossing easier. If you are going to brush the older person's teeth, stand behind ...

FLOSS 2013 : a survey dataset about free software contributors. Challenges for curating, sharing and combining

NARCIS (Netherlands)

Robles, G.; Arjona-Reina, L.; Vasilescu, B.N.; Serebrenik, A.; González-Barahona, J.M.; Devanbu, P.T.; Kim, S.; Pinzger, M.

2014-01-01

In this data paper we describe a data set obtained by means of performing an on-line survey to over 2,000 Free Libre Open Source Software (FLOSS) contributors. The survey includes questions related to personal characteristics (gender, age, civil status, nationality, etc.), education and level of

Infant motivation in dental health: attitude without constant reinforcement.

Science.gov (United States)

Teixeira Alves, Fabiana Bucholdz; Kuhn, Eunice; Bordin, Danielle; Kozlowski, Vitoldo Antonio; Raggio, Daniela Procida; Fadel, Cristina Berger

2014-01-01

Social factors determine the child's behavior and motivation is an important task in the teaching-learning process. This longitudinal and cross-sectional study aimed to analyze the effectiveness of a motivational activity program for oral hygiene habits formation after motivation and without constant reinforcement. The sample was constituted of 26 children (mean 6 years old) from a Public Kindergarten School in Ponta Grossa, PR, Brazil. Data were collected applying a test-chart, with figures reporting the process of dental health/illness. Some figures were considered positive to dental health (dentist/Cod 1, toothbrush/Cod 3, dentifrice/dental floss/Cod 6, fruits/vegetables/Cod 7 and tooth without caries lesion/Cod 8) and negative on dental health (sweets/Cod 2, bacteria/Cod 4, tooth with caries lesion/Cod 5). The figures presentation occurred in three different stages: First stage - figures were presented to children without previous knowledge; second stage - following the motivational presentation, and third stage - 30 days after the first contact. On the first stage, most children select good for the figures considered harmful to their teeth (Cod 2-88%; Cod 4-77% and Cod 5-65%). On the second stage, there was a lower percentage: 23% (P dental care.

21 CFR 178.3710 - Petroleum wax.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Petroleum wax. 178.3710 Section 178.3710 Food and... and Production Aids § 178.3710 Petroleum wax. Petroleum wax may be safely used as a component of nonfood articles in contact with food, in accordance with the following conditions: (a) Petroleum wax is a...

The status of dental caries and related factors in a sample of Iranian adolescents

DEFF Research Database (Denmark)

Pakpour, Amir H.; Hidarnia, Alireza; Hajizadeh, Ebrahim

2011-01-01

Objective: To describe the status of dental caries in a sample of Iranian adolescents aged 14 to 18 years in Qazvin, and to identify caries-related factors affecting this group. Study design: Qazvin was divided into three zones according to socio-economic status. The sampling procedure used...... was a stratified cluster sampling technique; incorporating 3 stratified zones, for each of which a cluster of school children were recruited from randomly selected high schools. The adolescents agreed to participate in the study and to complete a questionnaire. Dental caries status was assessed in terms of decayed...... their teeth on a regular basis. Although the incidence of caries was found to be moderate, it was influenced by demographic factors such as age and gender in addition to socio-behavioral variables such as family income, the level of education attained by parents, the frequency of dental brushing and flossing...

A comparative study of additive and subtractive manufacturing for dental restorations.

Science.gov (United States)

Bae, Eun-Jeong; Jeong, Il-Do; Kim, Woong-Chul; Kim, Ji-Hwan

2017-08-01

Digital systems have recently found widespread application in the fabrication of dental restorations. For the clinical assessment of dental restorations fabricated digitally, it is necessary to evaluate their accuracy. However, studies of the accuracy of inlay restorations fabricated with additive manufacturing are lacking. The purpose of this in vitro study was to evaluate and compare the accuracy of inlay restorations fabricated by using recently introduced additive manufacturing with the accuracy of subtractive methods. The inlay (distal occlusal cavity) shape was fabricated using 3-dimensional image (reference data) software. Specimens were fabricated using 4 different methods (each n=10, total N=40), including 2 additive manufacturing methods, stereolithography apparatus and selective laser sintering; and 2 subtractive methods, wax and zirconia milling. Fabricated specimens were scanned using a dental scanner and then compared by overlapping reference data. The results were statistically analyzed using a 1-way analysis of variance (α=.05). Additionally, the surface morphology of 1 randomly (the first of each specimen) selected specimen from each group was evaluated using a digital microscope. The results of the overlap analysis of the dental restorations indicated that the root mean square (RMS) deviation observed in the restorations fabricated using the additive manufacturing methods were significantly different from those fabricated using the subtractive methods (Padditive manufacturing methods (P=.466). Similarly, no significant differences were found between wax and zirconia, the subtractive methods (P=.986). The observed RMS values were 106 μm for stereolithography apparatus, 113 μm for selective laser sintering, 116 μm for wax, and 119 μm for zirconia. Microscopic evaluation of the surface revealed a fine linear gap between the layers of restorations fabricated using stereolithography apparatus and a grooved hole with inconsistent weak scratches

Wax deposition in crude oil pipelines

Energy Technology Data Exchange (ETDEWEB)

Assuncao, Pablo Morelato; Rodrigues, Lorennzo Marrochi Nolding [Universidade Federal do Espirito Santo, Sao Mateus, ES (Brazil). Centro Universitario Norte do Espirito Santo. Engenharia de Petroleo; Romero, Mao Ilich [University of Wyoming, Laramie, WY (United States). Enhanced Oil Recovery Institute], e-mail: mromerov@uwyo.edu

2010-07-01

Crude oil is a complex mixture of hydrocarbons which consists of aromatics, paraffins, naphthenics, resins asphaltenes, etc. When the temperature of crude oil is reduced, the heavy components, like paraffin, will precipitate and deposit on the pipe internal wall in the form of a wax-oil gel. The gel deposit consists of wax crystals that trap some amount of oil. As the temperature gets cooler, more wax will precipitate and the thickness of the wax gel will increase, causing gradual solidification of the crude and eventually the oil stop moving inside the offshore pipeline. Crude oil may not be able to be re-mobilized during re-startup. The effective diameter will be reduced with wax deposition, resulting in several problems, for example, higher pressure drop which means additional pumping energy costs, poor oil quality, use of chemical components like precipitation inhibitors or flowing facilitators, equipment failure, risk of leakage, clogging of the ducts and process equipment. Wax deposition problems can become so sever that the whole pipeline can be completely blocked. It would cost millions of dollars to remediate an offshore pipeline that is blocked by wax. Wax solubility decreases drastically with decreasing temperature. At low temperatures, as encountered in deep water production, is easy to wax precipitate. The highest temperature below which the paraffins begins to precipitate as wax crystals is defined as wax appearance temperature (WAT). Deposition process is a complex free surface problem involving thermodynamics, fluid dynamics, mass and heat transfer. In this work, a numerical analysis of wax deposition by molecular diffusion and shear dispersion mechanisms in crude oil pipeline is studied. Diffusion flux of wax toward the wall is estimated by Fick's law of diffusion, in similar way the shear dispersion; wax concentration gradient at the solid-liquid interface is obtained by the volume fraction conservation equation; and since the wax deposition

Effects of air pollutants on epicuticular wax structure

International Nuclear Information System (INIS)

Huttunen, S.

1994-01-01

In xerophytes, like conifers, the epicuticular wax is well developed. Especially in and around stomatal entrances, a thick wax coating is present. Epicuticular waxes are modified by changes in plant growth conditions such as temperature, relative humidity, irradiance, and wind, or acid rain. The fine structure of epicuticular waxes, their chemistry, and ecophysiological function are modified, especially in evergreen, long-lived conifer needles with characteristic crystalline wax structures. During needle flushing and development, wax structure is easily modified. Acid rain-treated Scots pine needles had 50% less epicuticular waxes in early August. Pollution-induced delayed development, destruction, and disturbances have been identified in many plant species. The structural changes in wax crystals are known. Acid rain or polluted air can destroy the crystalloid epicuticular waxes in a few weeks. In Pinus sylvestris, the first sign of pollution effect is the fusion of wax tubes. In Picea abies and P. sitchensis, modifications of crystalloid wax structure are known. In Californian pine trees phenomena of recrystallization of wax tubes on second-year needles were observed after delayed epicuticular wax development in Pinus ponderosa and P. coulteri. Thus, the effects of air pollutants are modified by climate. Accelerated senescence of leaves and needles have been associated with natural and anthropogenic stresses. The accelerated erosion rate of epicuticular waxes has been measured under air pollution conditions. Many short-term air pollution experiments have failed to show any structural changes in epicuticular wax structures. The quantity and quality of needle waxes grown in open-top chambers, glass houses, or polluted air before treatment, differ from field conditions and make it difficult to detect effects of any treatment. (orig.)

Going to the Dentist

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español Going to the Dentist KidsHealth / For Kids / Going to ... your teeth at home. Flossing involves using a piece of waxy string called dental floss to get ...

Refining of wax-containing oil by distillation

Energy Technology Data Exchange (ETDEWEB)

1930-04-28

A continuous method is disclosed for producing low cold test oil from wax-containing mineral oil, which comprises continuously heating the oil in a tubular heater with avoidance of cracking, and fractionating the resulting liquid and vapor in a fractionating tower with reflux to produce a wax-containing fraction having therein substantially all of the amorphous wax and being sufficiently free of crystalline wax so as to be waxable by a method suitable for the removal of amorphous wax.

21 CFR 172.888 - Synthetic petroleum wax.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Synthetic petroleum wax. 172.888 Section 172.888... CONSUMPTION Multipurpose Additives § 172.888 Synthetic petroleum wax. Synthetic petroleum wax may be safely used in or on foods in accordance with the following conditions: (a) Synthetic petroleum wax is a...

Bluetooth technology for prevention of dental caries.

Science.gov (United States)

Kolahi, Jafar; Fazilati, Mohamad

2009-12-01

Caries is caused when the pH at the tooth surface drops below 5.5. A miniaturized and autonomous pH monitoring nodes can be attached to the tooth surface, like a tooth jewel. This intelligent sensor includes three components: (a) digital micro pH meter, (b) power supply, (c) wireless communicating device. The micro pH meter facilitates long term tooth surface pH monitoring and providing real time feedback to the patients and dental experts. Power supply of this system will be microfabricated biocatalytic fuel cell (enzymatic micro-battery) using organic compounds (e.g. formate or glucose) as the fuel to generate electricity. When micro pH meter detects the pH lower than 5.5, wireless Bluetooth device sends a caution (e.g. "you are at risk of dental caries") to external monitoring equipment such as mobile phone or a hands-free heads. After reception of the caution, subjects should use routine brushing and flossing procedure or use a medicated chewing gum (e.g. chlorhexidine containing chewing gum) or rinse with a mouthwash.

Dental anatomy grading: comparison between conventional visual and a novel digital assessment technique.

Science.gov (United States)

Kwon, So Ran; Restrepo-Kennedy, Natalia; Dawson, Deborah V; Hernandez, Marcela; Denehy, Gerald; Blanchette, Derek; Gratton, David G; Aquilino, Steven A; Armstrong, Steven R

2014-12-01

Conventional grading of dental students' projects in preclinical courses has mainly relied on visual evaluation by experienced instructors. The purpose of this study was to compare conventional visual grading in a dental anatomy course at one U.S. dental school to a novel digital assessment technique. A total of sixty samples comprised of two sets of faculty wax-ups (n=30), student wax-ups (n=15), and dentoform teeth of tooth #14 (n=15) were used for this study. Two additional faculty members visually graded the samples according to a checklist and then repeated the grading after one week. The sample wax-up with the highest score based on the visual grading was selected as the master model for the digital grading, which was also performed twice with an interim period of one week. Descriptive statistics and signed rank tests for systematic bias were used for intra- and interrater comparisons. The intraclass correlation (ICC) was used as a measure of intra- and interrater reliability. None of the faculty members achieved the minimum acceptable intrarater agreement of 0.8. Interrater agreement was substantially less than intrarater agreement for the visual grading, whereas all measures of intrarater agreement were greater than 0.9 and considered excellent for the digital assessment technique. These results suggest that visual grading is limited by modest intrarater reliability and low interrater agreement. Digital grading is a promising evaluation method showing excellent intrarater reliability and correlation. Correlation for visual and digital grading was consistently modest, partly supporting the potential use of digital technology in dental anatomy grading.

21 CFR 582.1978 - Carnauba wax.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Carnauba wax. 582.1978 Section 582.1978 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1978 Carnauba wax. (a) Product. Carnauba wax. (b) Conditions of use. This substance is generally...

21 CFR 186.1555 - Japan wax.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Japan wax. 186.1555 Section 186.1555 Food and Drugs... Substances Affirmed as GRAS § 186.1555 Japan wax. (a) Japan wax (CAS Reg. No. 8001-39-6), also known as Japan... fruits of the oriental sumac, Rhus succedanea (Japan, Taiwan, and Indo-China), R. vernicifera (Japan...

Structure and Biosynthesis of Branched Wax Compounds on Wild Type and Wax Biosynthesis Mutants of Arabidopsis thaliana.

Science.gov (United States)

Busta, Lucas; Jetter, Reinhard

2017-06-01

The cuticle is a waxy composite that protects the aerial organs of land plans from non-stomatal water loss. The chemical make-up of the cuticular wax mixture plays a central role in defining the water barrier, but structure-function relationships have not been established so far, in part due to gaps in our understanding of wax structures and biosynthesis. While wax compounds with saturated, linear hydrocarbon tails have been investigated in detail, very little is known about compounds with modified aliphatic tails, which comprise substantial portions of some plant wax mixtures. This study aimed to investigate the structures, abundances and biosynthesis of branched compounds on the species for which wax biosynthesis is best understood: Arabidopsis thaliana. Microscale derivatization, mass spectral interpretation and organic synthesis identified homologous series of iso-alkanes and iso-alcohols on flowers and leaves, respectively. These comprised approximately 10-15% of wild type wax mixtures. The abundances of both branched wax constituents and accompanying unbranched compounds were reduced on the cer6, cer3 and cer1 mutants but not cer4, indicating that branched compounds are in part synthesized by the same machinery as unbranched compounds. In contrast, the abundances of unbranched, but not branched, wax constituents were reduced on the cer2 and cer26 mutants, suggesting that the pathways to both types of compounds deviate in later steps of chain elongation. Finally, the abundances of branched, but not unbranched, wax compounds were reduced on the cer16 mutant, and the (uncharacterized) CER16 protein may therefore be controlling the relative abundances of iso-alkanes and iso-alcohols on Arabidopsis surfaces. © The Author 2017. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Sintering of wax for controlling release from pellets.

Science.gov (United States)

Singh, Reena; Poddar, S S; Chivate, Amit

2007-09-14

The purpose of the present study was to investigate incorporation of hydrophobic (ie, waxy) material into pellets using a thermal sintering technique and to evaluate the pellets in vitro for controlled release. Pellets prepared by extrusion-spheronization technology were formulated with a water-soluble drug, microcrystalline cellulose, and carnauba wax. Powdered carnauba wax (4%-20%) prepared by grinding or by emulsification was studied with an attempt to retard the drug release. The inclusion of ground or emulsified carnauba wax did not sustain the release of theophylline for more than 3 hours. Matrix pellets of theophylline prepared with various concentrations of carnauba wax were sintered thermally at various times and temperatures. In vitro drug release profiles indicated an increase in drug release retardation with increasing carnauba wax concentration. Pellets prepared with ground wax showed a higher standard deviation than did those prepared with emulsified wax. There was incomplete release at the end of 12 hours for pellets prepared with 20% ground or emulsified wax. The sintering temperature and duration were optimized to allow for a sustained release lasting at least 12 hours. The optimized temperature and duration were found to be 100 degrees C and 140 seconds, respectively. The sintered pellets had a higher hydrophobicity than did the unsintered pellets. Scanning electron micrographs indicated that the carnauba wax moved internally, thereby increasing the surface area of wax within the pellets.

Impact of digital prosthodontic planning on dental esthetics: Biometric analysis of esthetic parameters.

Science.gov (United States)

Abduo, Jaafar; Bennamoun, Mohammed; Tennant, Marc; McGeachie, John

2016-01-01

Improving dental esthetics is a main objective of prosthodontic treatment. Recently, digital diagnostic waxing has been proposed as an alternative to conventional diagnostic waxing; however, the impact on esthetics has not been evaluated. The purpose of this study was to evaluate the impact of diagnostic waxing on biometric esthetic variables and to compare the esthetic outcome achieved by digital waxing with conventional waxing. Three biometric variables were evaluated: perceived frontal proportion (PFP), width/height (W:H) ratio, and symmetry. Maxillary casts of 13 patients were collected. All of them had maxillary anterior teeth that required prosthodontic treatment. Two forms of diagnostic waxing were executed: conventional and digital waxing. Measurements of the esthetic variables were conducted digitally. For the PFP, a frontal image was made and the width of each tooth was measured. Subsequently, the PFP values of the lateral incisor to central incisor and of the canine to central incisor were calculated. In addition, the height and width of each tooth was measured to calculate the W:H ratio. Using the previous measurements, the symmetry between the right and left sides was determined. No consistent or recurrent PFP was detected for any cast. The diagnostic waxing did not alter the PFP of the pretreatment casts. The diagnostic waxing had restored the W:H ratio to what is assumed to be a natural ratio. An improvement in symmetry was detected after the diagnostic waxing and was more prominent after the digital waxing. However, no significant difference was found between the 2 diagnostic waxing methods. The 2 diagnostic waxing methods influenced the esthetic variables of the anterior maxillary teeth and yielded similar outcomes. Digital waxing appears to be a reasonable alternative, but further investigations are needed to ensure its practicality. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights

Effect of solvent extraction on Tunisian esparto wax composition

Directory of Open Access Journals (Sweden)

Saâd Inès

2016-08-01

Full Text Available The increase of needs for renewable and vegetable based materials will help to drive the market growth of vegetable waxes. Because of their highly variable composition and physicochemical properties, plant waxes have found numerous applications in the: food, cosmetic, candle, coating, polish etc... The aim of this project is to determine the effect of solvent extraction (petroleum ether and ethanol on Tunisian esparto wax composition. The GC-MS was applied in order to determine the waxes compositions. Then, physicochemical parameters of these two samples of waxes: acid value, saponification value, iodine value and melting point were measured in order to deduct their properties and possible fields of uses. Results showed that esparto wax composition depended on the solvent extraction and that major components of the two samples of waxes were: alkanes, esters of fatty acids and phenols. Furthermore, esparto waxes were characterized by an antioxidant and antibacterial activities but the potential of these activities depended on the solvent of wax extraction.

Motivating and Inhibiting Factors to Oral-Dental Health Behavior in Adolescents: a Cross-Sectional Study

Directory of Open Access Journals (Sweden)

Zahra Hosseini

2016-11-01

Full Text Available Background Oral-dental diseases, especially tooth decay, are among the most common diseases in the world which usually begin in adolescence. Oral health during this period of life has a huge impact on the reduction of dental problems. This study aimed to determine motivating and inhibiting factors to oral-dental health behavior in adolescents. Materials and Methods This cross-sectional which had a descriptive and analytical design was conducted on 10-12th grade students in Kashan city, Iran. Using multi-stage sampling method and based on sampling size formula, a total of 290 of the students were randomly selected from the schools and were enrolled into the study. Then they received a research-made questionnaire containing questions about the knowledge and motivating and inhibiting factors to oral-dental health behavior. The collected data were analyzed using SPSS V.20 by independent t-test, ANOVA, and Pearson correlation coefficient. Results Of all, 62.8% of students brushed their teeth at least once a day. Moreover, 11.7% used dental floss once a day and 6.6% visited a dentist every six months. Oral-dental health behavior had a significant relationship with gender (P0.05. Conclusion When designing educational plans and interventions for improving oral-dental health behavior in students, it is necessary to adopt measures to enhance motivating factors and eliminate inhibiting factors.

Take Care of Your Teeth and Gums

Science.gov (United States)

... don’t have dental insurance, you can get dental care. Find a health center near you to learn more . Get tips for finding low-cost dental care . Next section Healthy Habits Previous section Flossing Tips ...

Natural oils and waxes: studies on stick bases.

Science.gov (United States)

Budai, Lívia; Antal, István; Klebovich, Imre; Budai, Marianna

2012-01-01

The objective of the present article was to examine the role of origin and quantity of selected natural oils and waxes in the determination of the thermal properties and hardness of stick bases. The natural oils and waxes selected for the study were sunflower, castor, jojoba, and coconut oils. The selected waxes were yellow beeswax, candelilla wax, and carnauba wax. The hardness of the formulations is a critical parameter from the aspect of their application. Hardness was characterized by the measurement of compression strength along with the softening point, the drop point, and differential scanning calorimetry (DSC). It can be concluded that coconut oil, jojoba oil, and carnauba wax have the greatest influence on the thermal parameters of stick bases.

Increased production of wax esters in transgenic tobacco plants by expression of a fatty acid reductase:wax synthase gene fusion.

Science.gov (United States)

Aslan, Selcuk; Hofvander, Per; Dutta, Paresh; Sun, Chuanxin; Sitbon, Folke

2015-12-01

Wax esters are hydrophobic lipids consisting of a fatty acid moiety linked to a fatty alcohol with an ester bond. Plant-derived wax esters are today of particular concern for their potential as cost-effective and sustainable sources of lubricants. However, this aspect is hampered by the fact that the level of wax esters in plants generally is too low to allow commercial exploitation. To investigate whether wax ester biosynthesis can be increased in plants using transgenic approaches, we have here exploited a fusion between two bacterial genes together encoding a single wax ester-forming enzyme, and targeted the resulting protein to chloroplasts in stably transformed tobacco (Nicotiana benthamiana) plants. Compared to wild-type controls, transgenic plants showed both in leaves and stems a significant increase in the total level of wax esters, being eight-fold at the whole plant level. The profiles of fatty acid methyl ester and fatty alcohol in wax esters were related, and C16 and C18 molecules constituted predominant forms. Strong transformants displayed certain developmental aberrations, such as stunted growth and chlorotic leaves and stems. These negative effects were associated with an accumulation of fatty alcohols, suggesting that an adequate balance between formation and esterification of fatty alcohols is crucial for a high wax ester production. The results show that wax ester engineering in transgenic plants is feasible, and suggest that higher yields may become achieved in the near future.

Wax-bonding 3D microfluidic chips

KAUST Repository

Gong, Xiuqing; Yi, Xin; Xiao, Kang; Li, Shunbo; Kodzius, Rimantas; Qin, Jianhua; Wen, Weijia

2013-01-01

We report a simple, low-cost and detachable microfluidic chip incorporating easily accessible paper, glass slides or other polymer films as the chip materials along with adhesive wax as the recycling bonding material. We use a laser to cut through the paper or film to form patterns and then sandwich the paper and film between glass sheets or polymer membranes . The hot-melt adhesive wax can realize bridge bonding between various materials, for example, paper, polymethylmethacrylate (PMMA) film, glass sheets, or metal plate. The bonding process is reversible and the wax is reusable through a melting and cooling process. With this process, a three-dimensional (3D) microfluidic chip is achievable by vacuating and venting the chip in a hot-water bath. To study the biocompatibility and applicability of the wax-based microfluidic chip, we tested the PCR compatibility with the chip materials first. Then we applied the wax-paper based microfluidic chip to HeLa cell electroporation (EP ). Subsequently, a prototype of a 5-layer 3D chip was fabricated by multilayer wax bonding. To check the sealing ability and the durability of the chip, green fluorescence protein (GFP) recombinant Escherichia coli (E. coli) bacteria were cultured, with which the chemotaxis of E. coli was studied in order to determine the influence of antibiotic ciprofloxacin concentration on the E. coli migration.

Wax-bonding 3D microfluidic chips

KAUST Repository

Gong, Xiuqing

2013-10-10

We report a simple, low-cost and detachable microfluidic chip incorporating easily accessible paper, glass slides or other polymer films as the chip materials along with adhesive wax as the recycling bonding material. We use a laser to cut through the paper or film to form patterns and then sandwich the paper and film between glass sheets or polymer membranes . The hot-melt adhesive wax can realize bridge bonding between various materials, for example, paper, polymethylmethacrylate (PMMA) film, glass sheets, or metal plate. The bonding process is reversible and the wax is reusable through a melting and cooling process. With this process, a three-dimensional (3D) microfluidic chip is achievable by vacuating and venting the chip in a hot-water bath. To study the biocompatibility and applicability of the wax-based microfluidic chip, we tested the PCR compatibility with the chip materials first. Then we applied the wax-paper based microfluidic chip to HeLa cell electroporation (EP ). Subsequently, a prototype of a 5-layer 3D chip was fabricated by multilayer wax bonding. To check the sealing ability and the durability of the chip, green fluorescence protein (GFP) recombinant Escherichia coli (E. coli) bacteria were cultured, with which the chemotaxis of E. coli was studied in order to determine the influence of antibiotic ciprofloxacin concentration on the E. coli migration.

Chemical composition of raw and deresinated peat waxes

Energy Technology Data Exchange (ETDEWEB)

Bel' kevich, P I; Ivanova, L A; Piskunova, T A; Tserlyukevich, Ya V; Yurkevich, E A

1980-01-01

Research was conducted using absorption chromatography and spectroscopy to study the changes in the chemical composition of raw peat wax taking place in the deresination process. Characteristics of the raw, deresinated waxes and resins removed are given. The fractions obtained showed that both raw and deresinated wax contain the same basic compound classes: hydrocarbons, alcohols, complex ether and acids; but their proportions in the waxes are different. After deresination most of the dark-colored polyfunctional compounds, a portion of the soluble unsaturated hydrocarbons and alcohols, and all the sterenes transfer into the resin. This causes the light color and specific physical properties of deresinated wax. (13 refs.) (In Russian)

DENTAL CARIES AND TREATMENT NECESSITY IN INSTITUTIONALIZED DRUG USERS

Directory of Open Access Journals (Sweden)

Marina Ferraz Neves Oliveira

2016-11-01

Full Text Available Dependence on drugs is a complex disease, incurable and that its use persists in the face of extremely negative consequences. Objective: was to evaluate the prevalence and severity of caries in users of legal drugs. Methods:It is an epidemiological, cross-sectional, descriptive study, held with adults, users of legal and illegal drugs, institutionalized in rehabilitation centers of municipalities in the southwestern region of the state of Bahia. We used a form with sociodemographic questions about the use of licit and illicit drugs. To assess tooth decay, we used the decayed, missing and filled teeth index (DMFT, and the dental units were assessed with a World Health Organization (WHO Model probe and a dental mirror. Data were tabulated and analyzed in Excel. Results: 73 individuals were evaluated, aged between 18 and 64, mean age 35.5 (SD ± 10.7. It was found that 71.4% are single, 73,7% with low level of education, 74.6% do not use dental floss. Caries prevalence was 98.6%, DMF-T average 15.6. In 18-34 years old individuals, the DMF-T average was 12.1 and from 35 to 64 years old it was 19.8. Regarding dentition, 52.6% of the teeth were affected by the disease. Among the affected teeth, 39.9% were decayed, 44.1% lost and 16% filled. Conclusion: We conclude that there is a high prevalence of caries in this population. Among the dental needs, the restoration of the dental element has to be highlighted.

Substance Use, Dental Hygiene, and Physical Activity in Adult Patients with Single Ventricle Physiology

DEFF Research Database (Denmark)

Schrader, Anne-Marie Voss

2013-01-01

% are not flossing their teeth (32% in controls; OR = 1.32; P = 0.239); and 39% are not physically active (24% in controls; OR = 1.63; P = 0.069). CONCLUSIONS: While in general there was no significant differences in overall health behaviors between SVP patients and controls, SVP patients are less physically active......Substance Use, Dental Hygiene, and Physical Activity in Adult Patients with Single Ventricle Physiology. Overgaard D, Schrader AM, Lisby KH, King C, Christensen RF, Jensen HF, Moons P. Author information OBJECTIVES: The study aims to describe substance use, dental hygiene, and physical activity...... in adult survivors with single ventricle physiology (SVP) and to compare the behaviors with matched controls, while the patients are particularly at risk for general health problems. DESIGN: The present study is part of a larger research project on long-term outcomes in adult patients with SVP. A cross...

Effects of air pollutants on epicuticular wax chemical composition

International Nuclear Information System (INIS)

Percy, K.E.; McQuattie, C.J.; Rebbeck, J.A.

1994-01-01

There are numerous reports in the literature of modifications to epicuticular wax structure as a consequence of exposure to air pollutants. Most authors have used scanning electron microscopy (SEM) to describe changes in wax crystallite morphology or distribution. ''Erosion'' or ''weathering'' of crystalline structure into an amorphous state is the most common observation, particularly in the case of conifer needles having the characteristic tube crystallites comprised of nonacosan-10-ol. Wax structure is largely determined by its chemical composition. Therefore, many of the reported changes in wax structure due to air pollutants probably arise from direct interactions between pollutants such as ozone and wax biosynthesis. The literature describing changes in wax composition due to pollutants is briefly reviewed. New evidence is introduced in support of the hypothesis for a direct interaction between air pollutants and epicuticular wax Biosynthesis. (orig.)

75 FR 63200 - Petroleum Wax Candles From China

Science.gov (United States)

2010-10-14

... INTERNATIONAL TRADE COMMISSION [Investigation No. 731-TA-282 (Third Review)] Petroleum Wax Candles... five-year review concerning the antidumping duty order on petroleum wax candles from China. SUMMARY... antidumping duty order on petroleum wax candles from China would be likely to lead to continuation or...

Periodontal health of dental clients in a community health setting.

Science.gov (United States)

Darby, I; Phan, L; Post, M

2012-12-01

The aim of this study was to investigate the prevalence and severity of periodontal disease and possible risk factors in clients attending the Plenty Valley Community Health (PVCH) dental clinic. After ethics approval and calibration of examiners, all consenting patients attending PVCH were examined for periodontal status using the Community Periodontal Index (CPI) system and a World Health Organization (WHO) probe. A total of 2861 patients were screened, of which 1751 were female. The majority of patients were Australian born followed by Mediterranean birth. Just under 50% brushed their teeth twice a day and only 20% flossed regularly. It was found that 28.4% had CPI scores of 3 and 4 with only 3.1% recording 0 and a widespread presence of calculus. The severity of periodontal status increased with age, male gender, decreased frequency of brushing, lower level of education, diabetes and reflected country of birth. PVCH has a higher prevalence of periodontal disease than the most recent national survey which reflects the population studied. © 2012 Australian Dental Association.

75 FR 80843 - Petroleum Wax Candles From China

Science.gov (United States)

2010-12-23

... INTERNATIONAL TRADE COMMISSION [Investigation No. 731-TA-282 (Third Review)] Petroleum Wax Candles... Tariff Act of 1930 (19 U.S.C. 1675(c)), that revocation of the antidumping duty order on petroleum wax... contained in USITC Publication 4207 (December 2010), entitled Petroleum Wax Candles from China...

Line Laser as an Assistance for Facial and Dental Midlines Evaluation in Single-Splint Orthognathic Surgery.

Science.gov (United States)

Yu, Chung-Chih; Chen, Yu-Ray; Lin, James Cheng-Yi

2017-10-01

Coincidence of facial and dental midlines is one of the important goals in orthognathic-orthodontic treatment to achieve optimum facial aesthetics and good occlusal functions. Tools assisting diagnosis of facial midline are usually ruler or dental floss. These tools are usually hand held and hinder the global sight required in facial evaluation. Line laser device projects a steady narrow laser line and is commonly used in construction and carpentry to replace traditional chalk line tool. The authors take the advantages of line laser and incorporate it into facial evaluation in the authors' practice of single-splint orthognathic surgery.During June 2013 to May 2015, the authors used line laser device to evaluate facial and dental midlines in 28 patients of facial asymmetry requiring orthognathic surgery during consultation in office and intraoperative evaluation. The details of integrating this device to practice are described. All the patients showed improved facial symmetry and coincidence of facial and dental midlines after operation. Postoperative orthodontics were finished smoothly.Line laser is available from general utility stores and is safe to use according to laser safety regulation. From the authors' experiences, it is burden free to apply in facial and dental midlines evaluation and improves the practice.

Fulfillment of GMP standard, halal standard, and applying HACCP for production process of beef floss (Case study: Ksatria enterprise)

Science.gov (United States)

A'diat, Arkan Addien Al; Liquiddanu, Eko; Laksono, Pringgo Widyo; Sutopo, Wahyudi; Suletra, I. Wayan

2018-02-01

Along with the increasing number of the modern retail business in Indonesia, give an opportunity to small and medium enterprise (SME) to sell its products through the modern retailer. There are some obstacles faced by the SMEs, one of them is about product standard. Product standard that must be owned by SMEs are GMP standard and halal standard. This research was conducted to know the fulfillment by the beef floss enterprise in jagalan in fulfilling the GMP standard and halal. In addition, Hazard Analysis and Critical Control Points (HACCP) system was applied to analyze the process. HACCP which used in this research was based on the seven principles in SNI (Indonesian National Standard) 01-4852-1998. The seven principles included hazard analysis, critical control point (CCP) determination, critical limit establishment, CCP monitor system establishment, corrective action establishment, verification, and also documentation establishment that must be applied in preparing HACCP plan. Based on this case study, it is concluded that there were 5 CCPs : the boiling process, roasting process, frying process, the beef floss draining process, and the packaging process.

Genuine halitosis in patients with dental and laryngological etiologies of mouth odor: severity and role of oral hygiene behaviors.

Science.gov (United States)

Herman, Sabina; Lisowska, Grażyna; Herman, Joanna; Wojtyna, Ewa; Misiołek, Maciej

2018-04-01

The aims of the study were to determine the severity of halitosis and the association between oral hygiene practices and the severity of malodor in patients with dental and laryngological etiologies of genuine halitosis. Thirty-five laryngological and 40 dental patients with halitosis completed a structured interview and underwent laryngological and dental examinations. Halitosis was assessed using organoleptic and halimeter tests. Greater halitosis severity in laryngological patients was associated with worse clinical status of the palatine tonsils, less frequent toothbrushing, less frequent use of tongue cleaners, fewer daily meals, and increased use of mouthrinses. Among dental patients, more severe halitosis was associated with worse clinical status of the periodontium, more tongue coating, less saliva secretion, and less frequent use of dental floss, interdental toothbrushes, and tongue cleaners. Oral hygiene was found to be a key moderator of the relationship between status of the periodontium or tonsils and severity of halitosis. The severity of halitosis in laryngological patients and dental patients is essentially similar; however, oral hygiene routines are associated with different effects in each group. Consequently, individual recommendations for patients with halitosis should be adjusted for the underlying disease and emphasize the role of effective specific hygiene behaviors. © 2018 Eur J Oral Sci.

In vivo evaluation of insect wax for hair growth potential

Science.gov (United States)

Ma, Jinju

2018-01-01

Insect wax is secreted by Ericerus pela Chavanness. It has been traditionally used to treat hair loss in China, but few reports have been published on the hair growth-promoting effect of insect wax. In this work, we examined the hair growth-promoting effects of insect wax on model animals. Different concentrations of insect wax were topically applied to the denuded backs of mice, and 5% minoxidil was applied topically as a positive control. We found that insect wax significantly promoted hair growth in a dose-dependent manner, 45% and 30% insect wax both induced hair to regrow, while less visible hair growth was observed in blank controls on the 16th day. The experimental areas treated with 45% and 30% insect wax exhibited significant differences in hair scores compared to blank controls, and hair lengths in the 45% and 30% insect wax group was significantly longer than in blank controls on the 16th and 20th days. There were no new hair follicles forming in the treated areas, and the hair follicles were prematurely converted to the anagen phase from the telogen phase in experimental areas treated with 45% and 30% insect wax. Both 45% and 30% insect wax upregulated vascular endothelial growth factor expression. The results indicated that 45% and 30% insect wax showed hair growth-promoting potential approximately as potent as 5% minoxidil by inducing the premature conversion of telogen-to-anagen and by prolonging the mature anagen phase rather than increasing the number of hair follicles, which was likely related to the upregulation of VEGF expression. The dissociative policosanol in insect wax was considered the key ingredient most likely responsible for the hair growth promoting potential. PMID:29438422

In vivo evaluation of insect wax for hair growth potential.

Directory of Open Access Journals (Sweden)

Jinju Ma

Full Text Available Insect wax is secreted by Ericerus pela Chavanness. It has been traditionally used to treat hair loss in China, but few reports have been published on the hair growth-promoting effect of insect wax. In this work, we examined the hair growth-promoting effects of insect wax on model animals. Different concentrations of insect wax were topically applied to the denuded backs of mice, and 5% minoxidil was applied topically as a positive control. We found that insect wax significantly promoted hair growth in a dose-dependent manner, 45% and 30% insect wax both induced hair to regrow, while less visible hair growth was observed in blank controls on the 16th day. The experimental areas treated with 45% and 30% insect wax exhibited significant differences in hair scores compared to blank controls, and hair lengths in the 45% and 30% insect wax group was significantly longer than in blank controls on the 16th and 20th days. There were no new hair follicles forming in the treated areas, and the hair follicles were prematurely converted to the anagen phase from the telogen phase in experimental areas treated with 45% and 30% insect wax. Both 45% and 30% insect wax upregulated vascular endothelial growth factor expression. The results indicated that 45% and 30% insect wax showed hair growth-promoting potential approximately as potent as 5% minoxidil by inducing the premature conversion of telogen-to-anagen and by prolonging the mature anagen phase rather than increasing the number of hair follicles, which was likely related to the upregulation of VEGF expression. The dissociative policosanol in insect wax was considered the key ingredient most likely responsible for the hair growth promoting potential.

Statistical Optimization of Sustained Release Venlafaxine HCI Wax Matrix Tablet.

Science.gov (United States)

Bhalekar, M R; Madgulkar, A R; Sheladiya, D D; Kshirsagar, S J; Wable, N D; Desale, S S

2008-01-01

The purpose of this research was to prepare a sustained release drug delivery system of venlafaxine hydrochloride by using a wax matrix system. The effects of bees wax and carnauba wax on drug release profile was investigated. A 3(2) full factorial design was applied to systemically optimize the drug release profile. Amounts of carnauba wax (X(1)) and bees wax (X(2)) were selected as independent variables and release after 12 h and time required for 50% (t(50)) drug release were selected as dependent variables. A mathematical model was generated for each response parameter. Both waxes retarded release after 12 h and increases the t(50) but bees wax showed significant influence. The drug release pattern for all the formulation combinations was found to be approaching Peppas kinetic model. Suitable combination of two waxes provided fairly good regulated release profile. The response surfaces and contour plots for each response parameter are presented for further interpretation of the results. The optimum formulations were chosen and their predicted results found to be in close agreement with experimental findings.

Keeping Your Child's Teeth Healthy

Science.gov (United States)

... common childhood oral disease — dental cavities (also called dental caries). How Can We Prevent Cavities? Cavities happen when ... replacement for good brushing and regular flossing. What Dental Problems Can Happen? If you are prone to tooth decay or gum disease, your kids might be at ...

Effects of UV-B radiation on wax biosynthesis

International Nuclear Information System (INIS)

Barnes, J.; Paul, N.; Percy, K.; Broadbent, P.; McLaughlin, C.; Mullineaux, P.; Creissen, G.; Wellburn, A.

1994-01-01

Two genotypes of tobacco (Nicotiana tabacum L.) were exposed in controlled environment chambers to three levels of biologically effective ultraviolet-B radiation (UV-B BE ; 280-320nm): 0, 4.54 (ambient) and 5.66 (∼ 25% enhancement) kJ m -2 d -1 . After 28 days, the quantity of wax deposited on leaf surfaces was determined gravimetrically; epicuticular wax chemical composition was determined by capillary gas chromatography with homologue assignments confirmed by gas chromatography-mass spectrometry. Leaf wettability was assessed by measuring the contact angle of water droplets placed on leaf surfaces. Tobacco wax consisted of three major hydrocarbon classes: Straight-chain alkanes (C 27 -C 33 ) which comprised ∼ 59% of the hydrocarbon fraction, containing a predominance of odd-chain alkanes with C 31 as the most abundant homologue; branched-chain alkanes (C 25 -C 32 ) which comprised ∼38% of the hydrocarbon fraction with anteiso 3-methyltriacontane (C 30 ) as the predominant homologue; and fatty acids (C 14 -C 18 ) which comprised ∼ 3% of the wax. Exposure to enhanced UV-B radiation reduced the quantity of wax on the adaxial surface of the transgenic mutant, and resulted in marked changes in the chemical composition of the wax on the exposed leaf surface. Enhanced UV-B decreased the quantity of straight-chain alkanes, increased the quantity of branched-chain alkanes and fatty acids, and resulted in shifts toward shorter straight-chain lengths. Furthermore, UV-B-induced changes in wax composition were associated with increased wettability of tobacco leaf surfaces. Overall, the data are consistent with the view that UV-B radiation has a direct and fundamental effect on wax biosynthesis. Relationships between the physico-chemical nature of the leaf surface and sensitivity to UV-B radiation are discussed. (orig.)

Knowledge, Attitude and Practice of Oral and Dental Healthcare in Pregnant Women

Directory of Open Access Journals (Sweden)

Sunita Bamanikar

2013-07-01

Full Text Available Objectives: Pregnant women are more susceptible to periodontal disease like gingivitis. Periodontal disease may be associated with adverse pregnancy outcomes. There is no published literature on dental health in pregnant women in Brunei, Darussalam. The objective of this study was to assess women’s knowledge and attitude towards oral and dental health during pregnancy and to examine their self-care practices in relation to oral and dental health. This study was carried out at the maternal child health clinic, Jubli Perak Sengkurong Health Centre, Brunei, Darussalam.Methods: This was a cross-sectional descriptive and analytical study conducted at the maternal child health center in Brunei, Darussalam. The study group was comprised of 95 pregnant women attending the MCH clinic, Jubli Perak Sengkurong Health Centre, September 2010, using convenience sampling method. A self-administered questionnaire was used, after it was pre-tested and validated. Statistical analysis was done using SPSS version16.Results: Of the total study group, 97.9% responded to the questionnaire and participated in the study. All the women brushed at least twice daily. However, only 40.9% flossed daily, 31.2% brushed after meals and 26.9% had a dental check-up at least twice a year. The knowledge related to dental care was also poor among the pregnant women. Though the majority of them (96.8% agreed that women should have a dental check-up during pregnancy, only 55.9% actually practiced this. This raises serious concern since pregnant women may need extra oral and dental care due to susceptibility to gum diseases during pregnancy, which may contribute to low birth weight babies and premature births.Conclusion: This study highlights important gaps in dental knowledge and practices related to oral and dental healthcare among pregnant women in Brunei, Darussalam. More intense dental health education, including oral health promotion in maternal child health centers can lead to

Diversity of cuticular wax among Salix species and Populus species hybrids.

Science.gov (United States)

Cameron, Kimberly D; Teece, Mark A; Bevilacqua, Eddie; Smart, Lawrence B

2002-08-01

The leaf cuticular waxes of three Salix species and two Populus species hybrids, selected for their ability to produce high amounts of biomass, were characterized. Samples were extracted in CH(2)Cl(2) three times over the growing season. Low kV SEM was utilized to observe differences in the ultrastructure of leaf surfaces from each clone. Homologous series of wax components were classified into organic groups, and the variation in wax components due to clone, sample time, and their interaction was identified. All Salix species and Populus species hybrids showed differences in total wax load at each sampling period, whereas the pattern of wax deposition over time differed only between the Salix species. A strong positive relationship was identified between the entire homologous series of alcohols and total wax load in all clones. Similarly strong relationships were observed between fatty acids and total wax load as well as fatty acids and alcohols in two Salix species and one Populus species hybrid. One Salix species, S. dasyclados, also displayed a strong positive relationship between alcohols and alkanes. These data indicate that species grown under the same environmental conditions produce measurably different cuticular waxes and that regulation of wax production appears to be different in each species. The important roles cuticular waxes play in drought tolerance, pest, and pathogen resistance, as well as the ease of wax extraction and analysis, strongly suggest that the characteristics of the cuticular wax may prove to be useful selectable traits in a breeding program.

Microencapsulation of flavors in carnauba wax.

Science.gov (United States)

Milanovic, Jelena; Manojlovic, Verica; Levic, Steva; Rajic, Nevenka; Nedovic, Viktor; Bugarski, Branko

2010-01-01

The subject of this study is the development of flavor wax formulations aimed for food and feed products. The melt dispersion technique was applied for the encapsulation of ethyl vanillin in wax microcapsules. The surface morphology of microparticles was investigated using scanning electron microscope (SEM), while the loading content was determined by HPLC measurements. This study shows that the decomposition process under heating proceeds in several steps: vanilla evaporation occurs at around 200 °C, while matrix degradation starts at 250 °C and progresses with maxima at around 360, 440 and 520 °C. The results indicate that carnauba wax is an attractive material for use as a matrix for encapsulation of flavours in order to improve their functionality and stability in products.

Microencapsulation of Flavors in Carnauba Wax

Directory of Open Access Journals (Sweden)

Branko Bugarski

2010-01-01

Full Text Available The subject of this study is the development of flavor wax formulations aimed for food and feed products. The melt dispersion technique was applied for the encapsulation of ethyl vanillin in wax microcapsules. The surface morphology of microparticles was investigated using scanning electron microscope (SEM, while the loading content was determined by HPLC measurements. This study shows that the decomposition process under heating proceeds in several steps: vanilla evaporation occurs at around 200 °C, while matrix degradation starts at 250 °C and progresses with maxima at around 360, 440 and 520 °C. The results indicate that carnauba wax is an attractive material for use as a matrix for encapsulation of flavours in order to improve their functionality and stability in products.

Is the Periodontal Status a Risk Factor for the Development of ...

African Journals Online (AJOL)

2017-05-16

May 16, 2017 ... A positive correlation between the severities of psoriasis and dental disease was determined, but this ... The habit of using dental floss and usage of denture .... levels and accordingly more mobile teeth and tooth loss in.

Phototransformation of the herbicide sulcotrione on maize cuticular wax.

Science.gov (United States)

Ter Halle, Alexandra; Drncova, Daniela; Richard, Claire

2006-05-01

Vegetation plays a key role in environmental cycling and the fate of many organic pollutants. This is especially the case for pesticides because plant leaves are their first reaction environment after application. It is commonly accepted that photochemical reactions of pollutants on plants predominantly take place in the cuticular wax coating of the leaves. Thus, we used films made of either cuticular wax extracted from maize or carnauba gray wax as a model support. Under simulated sunlight irradiation, sulcotrione (a new class of triketone herbicides) sorbed on cuticular wax films was photolyzed and mainly underwent an intramolecular cyclization. The photoproduct is a chromone derivative which was isolated and fully characterized. It is reported for the first time as a sulcotrione degradation product. The photoreactivity of formulated sulcotrione at the surface of cuticular waxes was investigated too. It photodegraded more rapidly than nonformulated sulcotrione. This study also shows that the rate of sulcotrione photolysis was much faster than the rate of penetration into the wax; photolysis should be, thus, a relevant process in real conditions.

The use of a neodymium-iron-boron magnet device for positioning a multi-stranded wire retainer in lingual retention--a pilot study in humans.

Science.gov (United States)

Hahn, Wolfram; Fricke, Julia; Fricke-Zech, Susanne; Zapf, Antonia; Gruber, Rudolf; Sadat-Khonsari, Reza

2008-10-01

The aim of this study was to evaluate the time requirement of a newly developed device made of neodymium-iron-boron (NdFeB) magnets for positioning a multi-stranded, canine-to-canine retainer during bonding compared with dental floss and a transfer tray. Forty-five patients aged between 12 and 33 years (26 male, 19 female) previously treated with fixed appliances were enrolled in the study. The patients were randomly allocated to three groups (15 per group). For each group a mandibular canine-to-canine retainer of 0.018 inch Dentaflex multi-stranded wire (Dentaurum) was prefabricated for each patient on a cast. The bonding procedure was identical, except for the method of positioning the wire during adhesive fixation: group A dental floss, group B a small prefabricated transfer tray of dental resin and group C the NdFeB magnet device. For each group, the time required for the complete bonding process was measured. Kruskal-Wallis and Wilcoxon-Mann-Whitney tests were used for group and pairwise comparisons, respectively. The three methods required statistically significant different times (P NdFeB magnet device is a timesaving appliance for positioning a multi-stranded, canine-to-canine retainer during bonding when compared with dental floss and an individually prefabricated transfer tray.

Infant motivation in dental health: Attitude without constant reinforcement

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Fabiana Bucholdz Teixeira Alves

2014-01-01

Full Text Available Introduction: Social factors determine the child′s behavior and motivation is an important task in the teaching-learning process. This longitudinal and cross-sectional study aimed to analyze the effectiveness of a motivational activity program for oral hygiene habits formation after motivation and without constant reinforcement. Materials and Methods: The sample was constituted of 26 children (mean 6 years old from a Public Kindergarten School in Ponta Grossa, PR, Brazil. Data were collected applying a test-chart, with figures reporting the process of dental health/illness. Some figures were considered positive to dental health (dentist/Cod 1, toothbrush/Cod 3, dentifrice/dental floss/Cod 6, fruits/vegetables/Cod 7 and tooth without caries lesion/Cod 8 and negative on dental health (sweets/Cod 2, bacteria/Cod 4, tooth with caries lesion/Cod 5. The figures presentation occurred in three different stages: First stage - figures were presented to children without previous knowledge; second stage - following the motivational presentation, and third stage - 30 days after the first contact. Results: On the first stage, most children select good for the figures considered harmful to their teeth (Cod 2-88%; Cod 4-77% and Cod 5-65%. On the second stage, there was a lower percentage: 23% (P < 0.0001, 8% (P < 0.0001, and 23% (P = 0.0068 related to the Cod 2, 4, and 5. On the third stage, the results showed again an association with the good choice to these figures considered harmful (Cod 2-85%, Cod 4-65% and Cod 5-54% similar the results obtained on the first stage. Conclusion: The motivational programs performed without constant reinforcement does not have a positive influence in changing the child′s behavior related to a better dental care.

Preliminary evaluation of an aqueous wax emulsion for controlled-release coating.

Science.gov (United States)

Walia, P S; Stout, P J; Turton, R

1998-02-01

The purpose of this work was to evaluate the use of an aqueous carnauba wax emulsion (Primafresh HS, Johnson Wax) in a spray-coating process. This involved assessing the effectiveness of the wax in sustaining the release of the drug, theophylline. Second, the process by which the drug was released from the wax-coated pellets was modeled. Finally, a method to determine the optimum blend of pellets with different wax thicknesses, in order to yield a zero-order release profile of the drug, was addressed. Nonpareil pellets were loaded with theophylline using a novel powder coating technique. These drug-loaded pellets were then coated with different levels of carnauba wax in a 6-in. diameter Plexiglas fluid bed with a 3.5-in. diameter Wurster partition. Drug release was measured using a spin-filter dissolution device. The study resulted in continuous carnauba wax coatings which showed sustained drug release profile characteristics typical of a barrier-type, diffusion-controlled system. The effect of varying wax thickness on the release profiles was investigated. It was observed that very high wax loadings would be required to achieve long sustained-release times. The diffusion model, developed to predict the release of the drug, showed good agreement with the experimental data. However, the data exhibited an initial lag-time for drug release which could not be predicted a priori based on the wax coating thickness. A method of mixing pellets with different wax thicknesses was proposed as a way to approximate zero-order release.

Structural-mechanical model of wax crystal networks—a mesoscale cellular solid approach

International Nuclear Information System (INIS)

Miyazaki, Yukihiro; Marangoni, Alejandro G

2014-01-01

Mineral waxes are widely used materials in industrial applications; however, the relationship between structure and mechanical properties is poorly understood. In this work, mineral wax-oil networks were characterized as closed-cell cellular solids, and differences in their mechanical response predicted from structural data. The systems studied included straight-chain paraffin wax (SW)-oil mixtures and polyethylene wax (PW)-oil mixtures. Analysis of cryogenic-SEM images of wax-oil networks allowed for the determination of the length (l) and thickness (t) of the wax cell walls as a function of wax mass fraction (Φ). A linear relationship between t/l and Φ (t/l ∼ Φ 0.89 ) suggested that wax-oil networks were cellular solids of the closed-cell type. However, the scaling behavior of the elastic modulus with the volume fraction of solids did not agree with theoretical predictions, yielding the same scaling exponent, μ = 0.84, for both waxes. This scaling exponent obtained from mechanical measurements could be predicted from the scaling behavior of the effective wax cell size as a function of wax mass fraction in oil obtained by cryogenic scanning electron microscopy. Microscopy studies allowed us to propose that wax-oil networks are structured as an ensemble of close-packed spherical cells filled with oil, and that it is the links between cells that yield under simple uniaxial compression. Thus, the Young’s moduli for the links between cells in SW and PW wax systems could be estimated as E L (SW) = 2.76 × 10 9 Pa and E L (PW) = 1.64 × 10 9 Pa, respectively. The structural parameter responsible for the observed differences in the mechanical strength between the two wax-oil systems is the size of the cells. Polyethylene wax has much smaller cell sizes than the straight chain wax and thus displays a higher Young’s modulus and yield stress. (papers)

Plant surface wax affects parasitoid's response to host footprints

Science.gov (United States)

Rostás, Michael; Ruf, Daniel; Zabka, Vanessa; Hildebrandt, Ulrich

2008-10-01

The plant surface is the substrate upon which herbivorous insects and natural enemies meet and thus represents the stage for interactions between the three trophic levels. Plant surfaces are covered by an epicuticular wax layer which is highly variable depending on species, cultivar or plant part. Differences in wax chemistry may modulate ecological interactions. We explored whether caterpillars of Spodoptera frugiperda, when walking over a plant surface, leave a chemical trail (kairomones) that can be detected by the parasitoid Cotesia marginiventris. Chemistry and micromorphology of cuticular waxes of two barley eceriferum wax mutants ( cer-za.126, cer-yp.949) and wild-type cv. Bonus (wt) were assessed. The plants were then used to investigate potential surface effects on the detectability of caterpillar kairomones. Here we provide evidence that C. marginiventris responds to chemical footprints of its host. Parasitoids were able to detect the kairomone on wild-type plants and on both cer mutants but the response to cer-yp.949 (reduced wax, high aldehyde fraction) was less pronounced. Experiments with caterpillar-treated wt and mutant leaves offered simultaneously, confirmed this observation: no difference in wasp response was found when wt was tested against cer-za.126 (reduced wax, wt-like chemical composition) but wt was significantly more attractive than cer-yp.949. This demonstrates for the first time that the wax layer can modulate the detectability of host kairomones.

Process for separating liquid hydrocarbons from waxes

Energy Technology Data Exchange (ETDEWEB)

Sowa, F J

1948-03-08

A process is described for the separation of liquid hydrocarbons from waxes comprising adding to a mixture of liquid hydrocarbons and waxes a sufficient quantity of an organo-silicon compound to cause the separation of the hydrocarbon and wax. The organo-silicon compounds are selected from the class of organic silicanes and their hydrolysis products and polymers. The silicanes have the formula R/sub y/SiX/sub z/, in which R is a saturated or unsaturated hydrocarbon radical, X is a halogen or another hydrocarbon radical or an -OR group, y has a value 1, 2, or 3 and z has a value 1, 2, or 3.

21 CFR 155.120 - Canned green beans and canned wax beans.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Canned green beans and canned wax beans. 155.120... Vegetables § 155.120 Canned green beans and canned wax beans. (a) Identity—(1) Definition. Canned green beans and canned wax beans are the foods prepared from succulent pods of fresh green bean or wax bean plants...

Gluconeogenesis from storage wax in the cotyledons of jojoba seedlings.

Science.gov (United States)

Moreau, R A; Huang, A H

1977-08-01

The cotyledons of jojoba (Simmondsia chinensis) seeds contained 50 to 60% of their weight as intracellular wax esters. During germination there was a gradual decrease in the wax content with a concomitant rise in soluble carbohydrates, suggesting that the wax played the role of a food reserve. Thin layer chromatography revealed that both the fatty alcohol and fatty acid were metabolized. The disappearance of wax was matched with an increase of catalase, a marker enzyme of the gluconeogenic process in other fatty seedlings. Subcellular organelles were isolated by sucrose gradient centrifugation from the cotyledons at the peak stage of germination. The enzymes of the beta oxidation of fatty acid and of the glyoxylate cycle were localized in the glyoxysomes but not in the mitochondria. The glyoxysomes had specific activities of individual enzymes similar to those of the castor bean glyoxysomes. An active alkaline lipase was detected in the wax bodies at the peak stage of germination but not in the ungerminated seeds. No lipase was detected in glyoxysomes or mitochondria. After the wax in the wax bodies had been extracted with diethyl ether, the organelle membrane was isolated and it still retained the alkaline lipase. The gluconeogenesis from wax in the jojoba seedling appears to be similar, but with modification, to that from triglyceride in other fatty seedlings.

Wax ester profiling of seed oil by nano-electrospray ionization tandem mass spectrometry

Science.gov (United States)

2013-01-01

Background Wax esters are highly hydrophobic neutral lipids that are major constituents of the cutin and suberin layer. Moreover they have favorable properties as a commodity for industrial applications. Through transgenic expression of wax ester biosynthetic genes in oilseed crops, it is possible to achieve high level accumulation of defined wax ester compositions within the seed oil to provide a sustainable source for such high value lipids. The fatty alcohol moiety of the wax esters is formed from plant-endogenous acyl-CoAs by the action of fatty acyl reductases (FAR). In a second step the fatty alcohol is condensed with acyl-CoA by a wax synthase (WS) to form a wax ester. In order to evaluate the specificity of wax ester biosynthesis, analytical methods are needed that provide detailed wax ester profiles from complex lipid extracts. Results We present a direct infusion ESI-tandem MS method that allows the semi-quantitative determination of wax ester compositions from complex lipid mixtures covering 784 even chain molecular species. The definition of calibration prototype groups that combine wax esters according to their fragmentation behavior enables fast quantitative analysis by applying multiple reaction monitoring. This provides a tool to analyze wax layer composition or determine whether seeds accumulate a desired wax ester profile. Besides the profiling method, we provide general information on wax ester analysis by the systematic definition of wax ester prototypes according to their collision-induced dissociation spectra. We applied the developed method for wax ester profiling of the well characterized jojoba seed oil and compared the profile with wax ester-accumulating Arabidopsis thaliana expressing the wax ester biosynthetic genes MaFAR and ScWS. Conclusions We developed a fast profiling method for wax ester analysis on the molecular species level. This method is suitable to screen large numbers of transgenic plants as well as other wax ester samples

Wax-incorporated emulsion gel beads of calcium pectinate for intragastric floating drug delivery.

Science.gov (United States)

Sriamornsak, Pornsak; Asavapichayont, Panida; Nunthanid, Jurairat; Luangtana-Anan, Manee; Limmatvapirat, Sontaya; Piriyaprasarth, Suchada

2008-01-01

The purpose of this study was to prepare wax-incorporated pectin-based emulsion gel beads using a modified emulsion-gelation method. The waxes in pectin-olive oil mixtures containing a model drug, metronidazole, were hot-melted, homogenized and then extruded into calcium chloride solution. The beads formed were separated, washed with distilled water and dried for 12 h. The influence of various types and amounts of wax on floating and drug release behavior of emulsion gel beads of calcium pectinate was investigated. The drug-loaded gel beads were found to float on simulated gastric fluid if the sufficient amount of oil was used. Incorporation of wax into the emulsion gel beads affected the drug release. Water-soluble wax (i.e. polyethylene glycol) increased the drug release while other water-insoluble waxes (i.e. glyceryl monostearate, stearyl alcohol, carnauba wax, spermaceti wax and white wax) significantly retarded the drug release. Different waxes had a slight effect on the drug release. However, the increased amount of incorporated wax in the formulations significantly sustained the drug release while the beads remained floating. The results suggest that wax-incorporated emulsion gel beads could be used as a carrier for intragastric floating drug delivery.

The Validity of Subjects in Korean Dental Technicians' Licensing Examination

Directory of Open Access Journals (Sweden)

Woong-chul Kim

2005-06-01

Full Text Available This study prepared a basic framework for the development and improvement of Korean Dental Technicians' Licensing Examination, based on actual test questions. A peer review was conducted to ensure relevance to current practices in dental technology. For the statistical analysis, 1000 dental laboratory technicians were selected; specialists in dental laboratory technology (laboratory owners, educators, etc. were involved in creating valid and reliable questions. Results indicated that examination subjects should be divided into three categories: basic dental laboratory theory, dental laboratory specialties, and a practical examination. To ensure relevance to current practice, there should be less emphasis on basic dental laboratory theory, including health-related laws, and more emphasis on dental laboratory specialties. Introduction to dental anatomy should be separated from oral anatomy and tooth morphology; and fixed prosthodontics should be separated from crown and bridge technology and dental ceramics technology. Removable orthodontic appliance technology should be renamed 'orthodontic laboratory technology'. There should be less questions related to health related law, oral anatomy, dental hygiene, dental materials science and inlay, while the distribution ratio of questions related to tooth morphology should be maintained. There should be a decrease in the distribution ratio of questions related to crown and bridge technology, dental ceramics technology, complete dentures and removable partial dentures technology, and orthodontic laboratory technology. In the practical examination, the current multiple choice test should be replaced with tooth carving using wax or plaster. In dental laboratory specialties, subjects related to contemporary dental laboratory technology should be included in the test items.

Microencapsulation of Flavors in Carnauba Wax

OpenAIRE

Milanovic, Jelena; Manojlovic, Verica; Levic, Steva; Rajic, Nevenka; Nedovic, Viktor; Bugarski, Branko

2010-01-01

The subject of this study is the development of flavor wax formulations aimed for food and feed products. The melt dispersion technique was applied for the encapsulation of ethyl vanillin in wax microcapsules. The surface morphology of microparticles was investigated using scanning electron microscope (SEM), while the loading content was determined by HPLC measurements. This study shows that the decomposition process under heating proceeds in several steps: vanilla evaporation occurs at aroun...

Geometric accuracy of wax bade models manufactured in silicon moulds

Directory of Open Access Journals (Sweden)

G. Budzik

2010-01-01

Full Text Available The article presents the test results of the geometric accuracy of wax blade models manufactured in silicon moulds in the Rapid Tooling process, with the application of the Vacuum Casting technology. In batch production casting waxes are designed for the manufacture of models and components of model sets through injection into a metal die. The objective of the tests was to determine the possibility of using traditional wax for the production of casting models in the rapid prototyping process. Blade models made of five types of casting wax were measured. The definition of the geometric accuracy of wax blade models makes it possible to introduce individual modifications aimed at improving their shape in order to increase the dimensional accuracy of blade models manufactured in the rapid prototyping process.

Phase Change Insulation for Energy Efficiency Based on Wax-Halloysite Composites

International Nuclear Information System (INIS)

Zhao, Yafei; Thapa, Suvhashis; Weiss, Leland; Lvov, Yuri

2014-01-01

Phase change materials (PCMs) have gained extensive attention in thermal energy storage. Wax can be used as a PCM in solar storage but it has low thermal conductivity. Introducing 10% halloysite admixed into wax yields a novel composite (wax-halloysite) which has a thermal conductivity of 0.5 W/mK. To increase the base conductivity, graphite and carbon nanotubes were added into the PCM composite improving its thermal energy storage. Thermal conductivity of wax-halloysite-graphite (45/45/10%) composite showed increased conductivity of 1.4 W/mK (3 times higher than the base wax-halloysite composite). Wax- halloysite-graphite-carbon nanotubes (45/45/5/5%) composite showed conductivity of 0.85 W/mK while maintaining the original shape perfectly until 91 °C (above the original wax melting point). Thermal conductivity can be further increased with higher doping of carbon nanotubes. This new composites are promising heat storage material due to good thermal stability, high thermal/electricity conductivity and ability to preserve its shape during phase transitions

Dental attendance, perceptions of cost and self-care of school year 12 and 13 students: A focus on Southland, New Zealand.

Science.gov (United States)

Murray, Colleen; Densie, Ian Kenneth; Morgan, Christian

2015-12-01

Adolescents and emerging adults can provide dentists with many challenges. Little information is available on their perceptions of dental costs once they turn 18 and dentistry is no longer State-funded. The aim of this study was to explore the use of dental care by Southland students in years 12 and 13, their perceptions of the cost of four common dental procedures, self-related oral health and dental self-care habits, time off school related to dental problems, and knowledge and views regarding fluoride. After ethical approval, a 26-question survey was conducted of all Southland students in years 12 and 13. Data were statistically analysed in SPSS version 20 with the alpha value set at 0.05. The participation rate was 49.6%. Regular attendance for examinations was reported by 77.5% with non-attendance mainly related to attitudes around lack of importance or necessity. Reported dental attendance varied according to gender, ethnicity and decile rating of school attended. Although some were accurate in their estimations of dental costs, the standard deviation for all procedures was large. The majority thought that costs put people off going to the dentist. While 74.8% brushed their teeth at least twice daily, only 26.6% flossed regularly. Knowledge regarding fluoride was lacking. It may be advantageous to include education regarding costs of dental care with patients of this age. This may motivate them to improve their self-care and ensure that their oral health is of a high standard before their dental needs are no longer State-funded.

Surfactants and Desensitizing Wax Substitutes for TNT-Based Systems.

Science.gov (United States)

1994-10-01

greatly with the source of crude oil. Some crudes contain little wax. The U.S. crudes from Pennsylvania and the midcontinent areas contain high...years ago in Egypt for many different purposes. The term wax comes to us from the Anglo-Saxon "weax," the name given to material from the bee ...usually produced in the wild and not by large scale cultivation. Although plants produce small amounts of waxes in their tissues, seeds and pollen

Absorption and distribution of orally administered jojoba wax in mice.

Science.gov (United States)

Yaron, A; Samoiloff, V; Benzioni, A

1982-03-01

The liquid wax obtained from the seeds of the arid-land shrub jojoba (Simmondsia chinensis) is finding increasing use in skin treatment preparations. The fate of this wax upon reaching the digestive tract was studied. 14C-Labeled wax was administered intragastrically to mice, and the distribution of the label in the body was determined as a function of time. Most of the wax was excreted, but a small amount was absorbed, as was indicated by the distribution of label in the internal organs and the epididymal fat. The label was incorporated into the body lipids and was found to diminish with time.

Simple Synthesis Hydrogenated Castor Oil Fatty Amide Wax and Its Coating Characterization.

Science.gov (United States)

Yu, Xiuzhu; Wang, Ning; Zhang, Rui; Zhao, Zhong

2017-07-01

A simple method for incorporating amine groups in hydrogenated castor oil (HCO) to produce wax for beeswax or carnauba wax substitution in packaging and coating was developed. From the conversion rate of the products, HCO was reacted with ethanolamine at 150°C for 5 h, and the molar ratio of HCO and ethanolamine was 1:4. The hardness of the final product was seven times higher than that of beeswax, the cohesiveness of the final product was 1.3 times higher than that of beeswax and approximately one half of that of carnauba wax, and the melting point of the final product is 98°C. The Fourier transform Infrared spectroscopy showed that the amide groups were incorporated to form the amide products. In coating application, the results showed that the force of the final product coating cardboard was higher than that of beeswax and paraffin wax and less than that of carnauba wax. After 24 h soaking, the compression forces were decreased. HCO fatty acid wax can be an alternative wax for carnauba wax and beeswax in coating applications.

ASPHALT-RESIN-WAX DEPOSITS ANALYSIS WITH PETROLEUM REFINERY EQUIPMENT USAGE

Directory of Open Access Journals (Sweden)

Nadejda Bondar

2013-12-01

Full Text Available The methodology and analysis of wax deposits formed in-water-cooling tower, cistern and tank from wax petroleum were developed. It was shown, that deposits consist of organic (>90% and inorganic components – the first one was enriched by high molecular wax hydrocarbons, the second one – by mechanical impurities. The methods of deposits utilization were proposed

Computerized axial tomography : the tool in osseointegrated dental implants

International Nuclear Information System (INIS)

Fernandez-Lopez, Otton

2002-01-01

Failure rates in rehabilitations with osseointegrated implants are handled through appropriate radiographic preoperative planning. The appropriate length of the implant without running the risk of a perforation of vital structures, has been determined by a radiographic diagnosis. Computerized and conventional axial tomography have proved to be invaluable elements for pre-surgical evaluation. A radiologic guidance is elaborated to perform a computerized axial tomography (CT) of maxillary bones in totally edentulous patients. Surgical guides are constructed from a wax-up emanated from the information of the CT. The CT has proven to be an radiographic indispensable element to achieve the surgical-prosthetic success in osseointegrated dental implants. The CT has allowed the realization of a precise wax-up for making of surgical guide and a precise temporary prostheses in positioning of osseointegrated implants, with the consequent saving time and money for the rehabilitator and patient [es

Gluconeogenesis from Storage Wax in the Cotyledons of Jojoba Seedlings 1

Science.gov (United States)

Moreau, Robert A.; Huang, Anthony H. C.

1977-01-01

The cotyledons of jojoba (Simmondsia chinensis) seeds contained 50 to 60% of their weight as intracellular wax esters. During germination there was a gradual decrease in the wax content with a concomitant rise in soluble carbohydrates, suggesting that the wax played the role of a food reserve. Thin layer chromatography revealed that both the fatty alcohol and fatty acid were metabolized. The disappearance of wax was matched with an increase of catalase, a marker enzyme of the gluconeogenic process in other fatty seedlings. Subcellular organelles were isolated by sucrose gradient centrifugation from the cotyledons at the peak stage of germination. The enzymes of the β oxidation of fatty acid and of the glyoxylate cycle were localized in the glyoxysomes but not in the mitochondria. The glyoxysomes had specific activities of individual enzymes similar to those of the castor bean glyoxysomes. An active alkaline lipase was detected in the wax bodies at the peak stage of germination but not in the ungerminated seeds. No lipase was detected in glyoxysomes or mitochondria. After the wax in the wax bodies had been extracted with diethyl ether, the organelle membrane was isolated and it still retained the alkaline lipase. The gluconeogenesis from wax in the jojoba seedling appears to be similar, but with modification, to that from triglyceride in other fatty seedlings. Images PMID:16660087

Wax combs mediate nestmate recognition by guard honeybees

DEFF Research Database (Denmark)

D'Ettorre, Patrizia; Wenseleers, Tom; Dawson, Jenny

2006-01-01

Research has shown that the wax combs are important in the acquisition of colony odour in the honeybee, Apis mellifera. However, many of these studies were conducted in the laboratory or under artificial conditions. We investigated the role of the wax combs in nestmate recognition in the natural...

Wax Point Determinations Using Acoustic Resonance Spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Bostick, D.T.; Jubin, R.T.; Schmidt, T.W.

2001-06-01

The thermodynamic characterization of the wax point of a given crude is essential in order to maintain flow conditions that prevent plugging of undersea pipelines. This report summarizes the efforts made towards applying an Acoustic Cavity Resonance Spectrometer (ACRS) to the determination of pressures and temperatures at which wax precipitates from crude. Phillips Petroleum Company, Inc., the CRADA participant, supplied the ACRS. The instrumentation was shipped to Dr. Thomas Schmidt of ORNL, the CRADA contractor, in May 2000 after preliminary software development performed under the guidance of Dr. Samuel Colgate and Dr. Evan House of the University of Florida, Gainesville, Fl. Upon receipt it became apparent that a number of modifications still needed to be made before the ACRS could be precisely and safely used for wax point measurements. This report reviews the sequence of alterations made to the ACRS, as well as defines the possible applications of the instrumentation once the modifications have been completed. The purpose of this Cooperative Research and Development Agreement (CRADA) between Phillips Petroleum Company, Inc. (Participant) and Lockheed Martin Energy Research Corporation (Contractor) was the measurement of the formation of solids in crude oils and petroleum products that are commonly transported through pipelines. This information is essential in the proper design, operation and maintenance of the petroleum pipeline system in the United States. Recently, new petroleum discoveries in the Gulf of Mexico have shown that there is a potential for plugging of undersea pipeline because of the precipitation of wax. It is important that the wax points of the expected crude oils be well characterized so that the production facilities for these new wells are capable of properly transporting the expected production. The goal of this work is to perform measurements of solids formation in crude oils and petroleum products supplied by the Participant. It is

wax matrix tablets and its implication on dissolution prof

African Journals Online (AJOL)

acetaminophen-wax matrix tablet and hence its implication on dissolution profile. Acetaminophen-wax ... inertness, cost effectiveness, non- toxicity and more importantly their ... Liver Poole, England) at constant load (30 arbitrary units on the ...

Nest wax triggers worker reproduction in the bumblebee Bombus terrestris.

Science.gov (United States)

Rottler-Hoermann, Ann-Marie; Schulz, Stefan; Ayasse, Manfred

2016-01-01

Social insects are well known for their high level of cooperation. Workers of the primitively eusocial bumblebee Bombus terrestris are able to produce male offspring in the presence of a queen. Nonetheless, they only compete for reproduction, in the so-called competition phase, when the workforce is large enough to support the rearing of reproductives. So far, little is known about the proximate mechanisms underlying the shift between altruism and selfish behaviour in bumblebee workers. In this study, we have examined the influence of chemical cues from the nest wax on the onset of worker reproduction. Chemical analyses of wax extracts have revealed that the patterns and amounts of cuticular lipids change considerably during colony development. These changes in wax scent mirror worker abundance and the presence of fertile workers. In bioassays with queen-right worker groups, wax affects the dominance behaviour and ovarian development of workers. When exposed to wax from a colony in competition phase, workers start to compete for reproduction. We suggest that wax scent enables workers to time their reproduction by providing essential information concerning the social condition of the colony.

Characterization and chemical composition of epicuticular wax from banana leaves grown in Northern Thailand

Directory of Open Access Journals (Sweden)

Suporn Charumanee

2017-08-01

Full Text Available This study aimed to investigate the physicochemical properties and chemical composition of epicuticular wax extracted from leaves of Kluai Namwa, a banana cultivar which is widely grown in Northern Thailand. Its genotype was identified by a botanist. The wax was extracted using solvent extraction. The fatty acid profiles and physicochemical properties of the wax namely melting point, congealing point, crystal structures and polymorphism, hardness, color, and solubility were examined and compared to those of beeswax, carnauba wax and paraffin wax. The results showed that the genotype of Kluai Namwa was Musa acuminata X M. balbisiana (ABB group cv. Pisang Awak. The highest amount of wax extracted was 274 μg/cm2 surface area. The fatty acid composition and the physicochemical properties of the wax were similar to those of carnauba wax. It could be suggested that the banana wax could be used as a replacement for carnauba wax in various utilizing areas.

Oral Hygiene Practices among Saudi Arabian Children and Its Relation to Their Dental Caries Status

Directory of Open Access Journals (Sweden)

M. F. A. Quadri

2018-01-01

Full Text Available Dental caries is one of the most common preventable diseases occurring among children. The aim here is to survey the oral hygiene practices that are commonly followed by Arab children and to see its relationship with their dental caries status. A cross-sectional study with multistage random sampling technique was conducted. Sociodemographic data and information on oral hygiene practices like use of toothbrush, dental floss, siwak, frequency of brushing along with number of snack between meals per day, and consumption of sugar per day was obtained. Presence of plaque on tooth surfaces was reported using plaque index, which was followed by DMFT index to determine the dental caries status. Among the sample of 500 school children, the mean plaque score in male (mean = 0.69; SD = 0.50 was slightly higher than the female (mean = 0.66; SD = 0.46. Increased frequency of snacks (P=0.05; ß=0.08; CI = −0.00, 0.09 and sugar consumption (P=0.01; ß=0.16; CI = 0.04, 0.27 per day significantly showed higher values of DMFT. Also, the odds of dental caries among the school children who were irregular in brushing their teeth was higher in contrast to the children brushing once (P=0.03; OR = 0.89; CI = 0.70, 1.12 or twice (P=0.03; OR = 0.80; CI = 0.64, 0.93 per day. It is recommended that the dental public health practitioners here should consider the effect of oral hygiene practices on oral health status in order to design the future health promotion interventions.

Development of a Parafin Wax deposition Unit for Fused Deposition Modelling (FDM)

DEFF Research Database (Denmark)

D'Angelo, Greta; Hansen, Hans Nørgaard; Pedersen, David Bue

2014-01-01

. This project illustrates the redesign of an extrusion unit for the deposition of paraffin wax in Fused Deposition Modelling (FDM) instead of the conventional polymeric materials. Among the benefits and brought by the use of paraffin wax in such system are: the possibility to make highly complex and precise...... parts to subsequently use in a Lost Wax Casting process, multi-material Additive Manufacturing and the use of wax as support material during the production of complicated parts. Moreover it is believed that including waxes among the materials usable in FDM would promote new ways of using and exploring...

Investigation of liquid wax components of Egyptian jojoba seeds.

Science.gov (United States)

El-Mallah, Mohammed Hassan; El-Shami, Safinaz Mohammed

2009-01-01

Egyptian jojoba seeds newly cultivated in Ismailia desert in Egypt promoted us to determine its lipid components. Fatty alcohols, fatty acids, wax esters and sterols patterns were determined by capillary GLC whereas, tocopherols profile, isopropenoid alcohols and sterylglycosides were determined by HPLC. The Egyptian seeds are rich in wax esters (55 %) with fatty alcohols C20:1 and C22:1 as major components and amounted to 43.0 % and 45.6 % respectively followed by C24:1 and C18:1(9.6 % and 1.3 % respectively). The fatty acids profile showed that C20:1 is the major constituent (60 %) followed by C18:1 and C22:1 (14.5 and 11.8 % respectively) whereas C24:1 was present at low concentration amounted to 1.6 %. In addition, the Egyptian jojoba wax contained C18:2 fatty acid at a level of 8.7 %. Wax esters composition showed that the local wax had C42 and C40 esters as major components amounted to 51.1 and 30.1 % respectively. Also, it had C44 and C38 at reasonable amounts (10.0 and 6.3 % respectively). Whereas C36 and C46 were present at lower concentrations amounted to 1.4 and 1.1 respectively. The sterols analysis showed the presence of campe-, stigma-, beta-sito-, and isofuco- sterol amounting to 18.4 %, 6.9 %, 68.7 %, and 6.0 % respectively. The tocopherols pattern revealed that the local seed wax contained gamma-tocopherol as major constituent (79.2 %) followed by alpha-tocopherol (20.3 %). beta-tocopherol as well as delta-tocopherol were found as minor constituents. The isopropenoid alcohols and the sterylglycosides (free and acylated) were not detected. The wax is proposed to be used in oleo chemistry and cosmetics.

Policosanol fabrication from insect wax and optimization by response surface methodology.

Science.gov (United States)

Ma, Jinju; Ma, Liyi; Zhang, Hong; Zhang, Zhongquan; Wang, Youqiong; Li, Kai; Chen, Xiaoming

2018-01-01

Insect wax is a famous biological resource for the role in economic production in China. Insect wax is a good source of policosanol, which may is a candidate supplement in foodstuff and pharmaceuticals that has important physiological activities. Therefore, this work aims to investigate a high-yield and rapid method for policosanol fabrication from insect wax. The conditions for policosanol fabrication were optimized as follows: an oil bath temperature of 112.7°C and reductant dosage of 0.97 g (used for the reduction of 10.00 g of insect wax). The yield of policosanol reached 83.20%, which was 4 times greater than that of existing methods, such as saponification. The total content of policosanol obtained under the optimal conditions reached 87%. In other words, a high yield of policosanol was obtained from insect wax (723.84 mg/g), that was 55 times higher than that generated from beeswax-brown via saponification. The concentrations of metal residues in policosanol were within the limits of the European Union regulations and EFSA stipulation. The LD50 values for oral doses of insect wax and policosanol were both > 5 g/kg. Policosanol was fabricated via solvent-free reduction from insect wax using LiAlH4 at a high yield. The fabrication conditions were optimized. Policosanol and insect wax showed high security, which made them potential candidates as supplements in foods, pharmaceuticals and cosmetics. The rapid and high-yield method has great potential for commercial manufacturing of policosanol.

Content of Wax during Dewaxing Process: Adopting a DOE Method

Directory of Open Access Journals (Sweden)

Mohammad Hosein Eghbali

2013-01-01

Full Text Available The oil content of the wax produced in a dewaxing process is the key economic parameter that should be reduced as much as possible. Some factors such as the type of solvents, cooling rate, temperature, and solvent to oil ratio influence the dewaxing process. Due to the fact that crude oil differs from place to place and since the operational conditions for wax extraction vary for different types of crude oil, the objective of this work is to study the operational conditions for wax production from an Iranian raffinate sample used in Sepahan Oil Company. All the experiments are conducted based on a design of experiment (DOE technique for minimizing the oil content of the wax produced. The effects of five factors have been determined quantitatively and appropriate levels are suggested for reducing the oil content. The results show that the solvent ratio, solvent composition, and cooling rate play the most important role in minimizing the oil content of the produced wax.

Pickering emulsions stabilized by paraffin wax and Laponite clay particles.

Science.gov (United States)

Li, Caifu; Liu, Qian; Mei, Zhen; Wang, Jun; Xu, Jian; Sun, Dejun

2009-08-01

Emulsions containing wax in dispersed droplets stabilized by disc-like Laponite clay particles are prepared. Properties of the emulsions prepared at different temperatures are examined using stability, microscopy and droplet-size analysis. At low temperature, the wax crystals in the oil droplets can protrude through the interface, leading to droplet coalescence. But at higher temperatures, the droplet size decreases with wax concentration. Considering the viscosity of the oil phase and the interfacial tension, we conclude that the wax is liquid-like during the high temperature emulsification process, but during cooling wax crystals appear around the oil/water interface and stabilize the droplets. The oil/water ratio has minimal effect on the emulsions between ratios of 3:7 and 7:3. The Laponite is believed to stabilize the emulsions by increasing the viscosity of the continuous phase and also by adsorbing at the oil/water interface, thus providing a physical barrier to coalescence.

Evaluation of Wax Deposition and Its Control During Production of Alaska North Slope Oils

Energy Technology Data Exchange (ETDEWEB)

Tao Zhu; Jack A. Walker; J. Liang

2008-12-31

Due to increasing oil demand, oil companies are moving into arctic environments and deep-water areas for oil production. In these regions of lower temperatures, wax deposits begin to form when the temperature in the wellbore falls below wax appearance temperature (WAT). This condition leads to reduced production rates and larger pressure drops. Wax problems in production wells are very costly due to production down time for removal of wax. Therefore, it is necessary to develop a solution to wax deposition. In order to develop a solution to wax deposition, it is essential to characterize the crude oil and study phase behavior properties. The main objective of this project was to characterize Alaskan North Slope crude oil and study the phase behavior, which was further used to develop a dynamic wax deposition model. This report summarizes the results of the various experimental studies. The subtasks completed during this study include measurement of density, molecular weight, viscosity, pour point, wax appearance temperature, wax content, rate of wax deposition using cold finger, compositional characterization of crude oil and wax obtained from wax content, gas-oil ratio, and phase behavior experiments including constant composition expansion and differential liberation. Also, included in this report is the development of a thermodynamic model to predict wax precipitation. From the experimental study of wax appearance temperature, it was found that wax can start to precipitate at temperatures as high as 40.6 C. The WAT obtained from cross-polar microscopy and viscometry was compared, and it was discovered that WAT from viscometry is overestimated. From the pour point experiment it was found that crude oil can cease to flow at a temperature of 12 C. From the experimental results of wax content, it is evident that the wax content in Alaskan North Slope crude oil can be as high as 28.57%. The highest gas-oil ratio for a live oil sample was observed to be 619.26 SCF

WAX ActiveLibrary: a tool to manage information overload.

Science.gov (United States)

Hanka, R; O'Brien, C; Heathfield, H; Buchan, I E

1999-11-01

WAX Active-Library (Cambridge Centre for Clinical Informatics) is a knowledge management system that seeks to support doctors' decision making through the provision of electronic books containing a wide range of clinical knowledge and locally based information. WAX has been piloted in several regions in the United Kingdom and formally evaluated in 17 GP surgeries based in Cambridgeshire. The evaluation has provided evidence that WAX Active-Library significantly improves GPs' access to relevant information sources and by increasing appropriate patient management and referrals this might also lead to an improvement in clinical outcomes.

Reproduction and subchronic feeding study of carnauba wax in rats.

Science.gov (United States)

Parent, R A; Re, T A; Babish, J G; Cox, G E; Voss, K A; Becci, P J

1983-02-01

The reproductive performance of Wistar rats fed carnauba wax at levels of 0.1, 0.3 or 1% in the diet and the effects of subchronic administration of carnauba wax at these dose levels on the resultant progeny were studied. Reproductive indices, body-weight gain, food consumption, haematological and clinical chemical data, ophthalmic, gross and histopathological examinations were used to study the possible toxic or pathological effects. Serum free fatty acid levels were found to be decreased in male and female rats fed carnauba wax at dietary levels of 0.3 and 1.0%. No other effects of feeding carnauba wax at levels up to 1.0% of the diet were observed.

Molecular and Evolutionary Mechanisms of Cuticular Wax for Plant Drought Tolerance

Directory of Open Access Journals (Sweden)

Dawei Xue

2017-04-01

Full Text Available Cuticular wax, the first protective layer of above ground tissues of many plant species, is a key evolutionary innovation in plants. Cuticular wax safeguards the evolution from certain green algae to flowering plants and the diversification of plant taxa during the eras of dry and adverse terrestrial living conditions and global climate changes. Cuticular wax plays significant roles in plant abiotic and biotic stress tolerance and has been implicated in defense mechanisms against excessive ultraviolet radiation, high temperature, bacterial and fungal pathogens, insects, high salinity, and low temperature. Drought, a major type of abiotic stress, poses huge threats to global food security and health of terrestrial ecosystem by limiting plant growth and crop productivity. The composition, biochemistry, structure, biosynthesis, and transport of plant cuticular wax have been reviewed extensively. However, the molecular and evolutionary mechanisms of cuticular wax in plants in response to drought stress are still lacking. In this review, we focus on potential mechanisms, from evolutionary, molecular, and physiological aspects, that control cuticular wax and its roles in plant drought tolerance. We also raise key research questions and propose important directions to be resolved in the future, leading to potential applications of cuticular wax for water use efficiency in agricultural and environmental sustainability.

Uncovered secret of a Vasseur-Tramond wax model.

Science.gov (United States)

Pastor, J F; Gutiérrez, B; Montes, J M; Ballestriero, R

2016-01-01

The technique of anatomical wax modelling reached its heyday in Italy during the 18th century, through a fruitful collaboration between sculptors and anatomists. It soon spread to other countries, and prestigious schools were created in England, France, Spain and Austria. Paris subsequently replaced Italy as the major centre of manufacture, and anatomical waxes were created there from the mid-19th century in workshops such as that of Vasseur-Tramond. This workshop began to sell waxes to European Faculties of Medicine and Schools of Surgery around 1880. Little is known of the technique employed in the creation of such artefacts as this was deemed a professional secret. To gain some insight into the methods of construction, we have studied a Vasseur-Tramond wax model in the Valladolid University Anatomy Museum, Spain, by means of multi-slice computerised tomography and X-ray analysis by means of environmental scanning electron microscopy. Scanning electron microscopy was used to examine the hair. These results have revealed some of the methods used to make these anatomical models and the materials employed. © 2015 Anatomical Society.

Wax encapsulation of water-soluble compounds for application in foods.

Science.gov (United States)

Mellema, M; Van Benthum, W A J; Boer, B; Von Harras, J; Visser, A

2006-11-01

Water-soluble ingredients have been successfully encapsulated in wax using two preparation techniques. The first technique ('solid preparation') leads to relatively large wax particles. The second technique ('liquid preparation') leads to relatively small wax particles immersed in vegetable oil. On the first technique: stable encapsulation of water-soluble colourants (dissolved at low concentration in water) has been achieved making use of beeswax and PGPR. The leakage from the capsules, for instance of size 2 mm, is about 30% after 16 weeks storage in water at room temperature. To form such capsules a minimum wax mass of 40% relative to the total mass is needed. High amounts of salt or acids at the inside water phase causes more leaking, probably because of the osmotic pressure difference. Osmotic matching of inner and outer phase can lead to a dramatic reduction in leakage. Fat capsules are less suitable to incorporate water soluble colourants. The reason for this could be a difference in crystal structure (fat is less ductile and more brittle). On the second technique: stable encapsulation of water-soluble colourants (encapsulated in solid wax particles) has been achieved making use of carnauba wax. The leakage from the capsules, for instance of size 250 mm, is about 40% after 1 weeks storage in water at room temperature.

Content and goals of preclinical prosthodontic programs at german-language dental schools.

Science.gov (United States)

Hey, Jeremias; Stimmelmayr, Michael; Hirsch, Christian; Beuer, Florian

2014-04-01

The Association for Dental Education in Europe (ADEE) makes recommendations regarding the skills graduates of European dental schools need to achieve and advises dental schools regarding necessary changes to be made to the curriculum. In 2010 to 2011, a survey was conducted in German-language dental schools to validate the curricula and goals of preclinical prosthodontic programs with regard to laboratory work. The survey was mailed to the course instructors of the preclinical programs at 37 dental schools. Of these, 35 schools returned the completed survey, resulting in a response rate of 95%. Bent wire, wax-up exercises, metal-ceramic single crowns, fixed dental prostheses, cast metal single crowns, temporary removable dental prostheses, and full dentures were part of the dental laboratory work at most schools; however, most instructors considered laboratory work as less important, and there were few similarities among the programs in this area. According to the instructors responsible for preclinical education, honing of fine motor skills, realistic self-assessment, and the ability to work independently were the main goals of the programs. The results of this survey show that with regard to laboratory work, there were more differences than similarities among preclinical prosthodontic programs at German-language dental schools, contrary to the recommendations of the ADEE. These findings should be taken into account when program reforms are planned. © 2013 by the American College of Prosthodontists.

Comparison the Marginal and Internal Fit of Metal Copings Cast from Wax Patterns Fabricated by CAD/CAM and Conventional Wax up Techniques

Science.gov (United States)

Vojdani, M; Torabi, K; Farjood, E; Khaledi, AAR

2013-01-01

Statement of Problem: Metal-ceramic crowns are most commonly used as the complete coverage restorations in clinical daily use. Disadvantages of conventional hand-made wax-patterns introduce some alternative ways by means of CAD/CAM technologies. Purpose: This study compares the marginal and internal fit of copings cast from CAD/CAM and conventional fabricated wax-patterns. Materials and Method: Twenty-four standardized brass dies were prepared and randomly divided into 2 groups according to the wax-patterns fabrication method (CAD/CAM technique and conventional method) (n=12). All the wax-patterns were fabricated in a standard fashion by means of contour, thickness and internal relief (M1-M12: representative of CAD/CAM group, C1-C12: representative of conventional group). CAD/CAM milling machine (Cori TEC 340i; imes-icore GmbH, Eiterfeld, Germany) was used to fabricate the CAD/CAM group wax-patterns. The copings cast from 24 wax-patterns were cemented to the corresponding dies. For all the coping-die assemblies cross-sectional technique was used to evaluate the marginal and internal fit at 15 points. The Student’s t- test was used for statistical analysis (α=0.05). Results: The overall mean (SD) for absolute marginal discrepancy (AMD) was 254.46 (25.10) um for CAD/CAM group and 88.08(10.67) um for conventional group (control). The overall mean of internal gap total (IGT) was 110.77(5.92) um for CAD/CAM group and 76.90 (10.17) um for conventional group. The Student’s t-test revealed significant differences between 2 groups. Marginal and internal gaps were found to be significantly higher at all measured areas in CAD/CAM group than conventional group (pmarginal and internal fit than CAD/CAM (machine-milled) technique. All the factors for 2 groups were standardized except wax pattern fabrication technique, therefore, only the conventional group results in copings with clinically acceptable margins of less than 120um. PMID:24724133

Studies on Hydrotreating Process of Microcrystalline Wax Produced from Marine Belayim Crude Oil

International Nuclear Information System (INIS)

EI Karashi, S.; Marawan, H.

2004-01-01

Abstract Microcrystalline wax was produced from solvent dewaxing process of vacuum residue raffinate produced from Marine Belayim origin. The untreated microcrystalline wax contains trace amounts of sulfur, oxygen, nitrogen and organometallic compounds as well as heavy aromatics which affect the properties of wax applications in pharmaceutical and technical fields . Microcrystalline wax hydrotreating process was studied using digital controlled unit and Ni O-MoO 3 / Al 2 O 3 catalyst, where operating parameters that controlled the efficiency of the hydrotreated wax were studied separately at different values including reactor temperature, reactor pressure, liquid hourly space velocity and hydrogen to hydrocarbon ratio . Hydrotreated microcrystalline wax at operating conditions (temperature 300 degree C, pressure 73 kg/cm 2 , LHS V 0.52 h-l and H 2 /HC ratio 266.6 Nm 3 /m 3 ) has the best quality to be used as food grade wax

Maggie's Struggle in Placing Her Existence at the Patriarchal Society in the Mill on the Floss by George Elliot

OpenAIRE

INDRIANI, FRISCA ARUM

2013-01-01

Novel The Mill on the Floss is one of George Elliot's novels that describing the situation and condition of the English society and also representing human life in 1837-1901 century which is called Victorian Era. At the moment, women were dominated by men and considered inferior. The condition is portrayed in this novel because the novel tells about the life of women, especially the life of the main female character, Maggie Tulliver, who is the victim of the standard beauty in her family. It ...

Oils; lubricants; paraffin-wax compositions; hydrocarbon condensation products

Energy Technology Data Exchange (ETDEWEB)

1934-04-04

Petroleum hydrocarbons such as gasoline, kerosene, Diesel fuel oil, lubricating-oil, and paraffin wax, and like hydrocarbons such as are obtainable from shale oil and by the hydrogenation of carbonaceous materials, are improved by addition of products obtained by condensing a cyclic hydrocarbon with a saturated dihalogen derivative of an aliphatic hydrocarbon containing less than five carbon atoms. The addition of the condensation products increases the viscosity of the hydrocarbon oils specified, and is particularly useful in the case of lubricating-oils; addition of the condensation products to paraffin wax increases the transparency and adherent properties of the wax, and is useful in the manufacture of moulded articles such as candles; the products may also be used in solid lubricating-compositions.

Epicuticular wax on cherry laurel (Prunus laurocerasus) leaves does not constitute the cuticular transpiration barrier.

Science.gov (United States)

Zeisler, Viktoria; Schreiber, Lukas

2016-01-01

Epicuticular wax of cherry laurel does not contribute to the formation of the cuticular transpiration barrier, which must be established by intracuticular wax. Barrier properties of cuticles are established by cuticular wax deposited on the outer surface of the cuticle (epicuticular wax) and in the cutin polymer (intracuticular wax). It is still an open question to what extent epi- and/or intracuticular waxes contribute to the formation of the transpiration barrier. Epicuticular wax was mechanically removed from the surfaces of isolated cuticles and intact leaf disks of cherry laurel (Prunus laurocerasus L.) by stripping with different polymers (collodion, cellulose acetate and gum arabic). Scanning electron microscopy showed that two consecutive treatments with all three polymers were sufficient to completely remove epicuticular wax since wax platelets disappeared and cuticle surfaces appeared smooth. Waxes in consecutive polymer strips and wax remaining in the cuticle after treatment with the polymers were determined by gas chromatography. This confirmed that two treatments of the polymers were sufficient for selectively removing epicuticular wax. Water permeability of isolated cuticles and cuticles covering intact leaf disks was measured using (3)H-labelled water before and after selectively removing epicuticular wax. Cellulose acetate and its solvent acetone led to a significant increase of cuticular permeability, indicating that the organic solvent acetone affected the cuticular transpiration barrier. However, permeability did not change after two subsequent treatments with collodion and gum arabic or after treatment with the corresponding solvents (diethyl ether:ethanol or water). Thus, in the case of P. laurocerasus the epicuticular wax does not significantly contribute to the formation of the cuticular transpiration barrier, which evidently must be established by the intracuticular wax.

Development and Performance Evaluation of Image-Based Robotic Waxing System for Detailing Automobiles.

Science.gov (United States)

Lin, Chi-Ying; Hsu, Bing-Cheng

2018-05-14

Waxing is an important aspect of automobile detailing, aimed at protecting the finish of the car and preventing rust. At present, this delicate work is conducted manually due to the need for iterative adjustments to achieve acceptable quality. This paper presents a robotic waxing system in which surface images are used to evaluate the quality of the finish. An RGB-D camera is used to build a point cloud that details the sheet metal components to enable path planning for a robot manipulator. The robot is equipped with a multi-axis force sensor to measure and control the forces involved in the application and buffing of wax. Images of sheet metal components that were waxed by experienced car detailers were analyzed using image processing algorithms. A Gaussian distribution function and its parameterized values were obtained from the images for use as a performance criterion in evaluating the quality of surfaces prepared by the robotic waxing system. Waxing force and dwell time were optimized using a mathematical model based on the image-based criterion used to measure waxing performance. Experimental results demonstrate the feasibility of the proposed robotic waxing system and image-based performance evaluation scheme.

Electrically conductive carbon nanofiber/paraffin wax composites for electric thermal storage

International Nuclear Information System (INIS)

Zhang Kun; Han Baoguo; Yu Xun

2012-01-01

Highlights: ► Carbon nanofiber (CNF)/paraffin wax composite is found to be a promising electric thermal storage material. ► The thermal storage capacity of CNF/paraffin wax composite is five times of traditional electric thermal storage material. ► CNF is shown to be an effective conductive filler for the composite. - Abstract: The research of electric thermal storage (ETS) has attracted a lot of attention recently, which converts off-peak electrical energy into thermal energy and release it later at peak hours. In this study, new electric thermal storage composites are developed by employing paraffin wax as thermal storage media and carbon nanofiber (CNF) as conductive fillers. Electric heating and thermal energy release performances of the CNF/paraffin wax composites are experimentally investigated. Experimental results show that, when the composites are heated to about 70 °C, the developed electrically conductive CNF/paraffin wax composites present a thermal storage capacity of about 280 kJ/kg, which is five times of that of traditional thermal storage medium such as ceramic bricks (54 kJ/kg). The CNF/paraffin wax composites can also effectively store the thermal energy and release the thermal energy in later hours.

Marginal adaptation of four inlay casting waxes on stone, titanium, and zirconia dies.

Science.gov (United States)

Michalakis, Konstantinos X; Kapsampeli, Vassiliki; Kitsou, Aikaterini; Kirmanidou, Yvone; Fotiou, Anna; Pissiotis, Argirios L; Calvani, Pasquale Lino; Hirayama, Hiroshi; Kudara, Yukio

2014-07-01

Different inlay casting waxes do not produce copings with satisfactory marginal accuracy when used on different die materials. The purpose of this study was to evaluate the marginal accuracy of 4 inlay casting waxes on stone dies and titanium and zirconia abutments and to correlate the findings with the degree of wetting between the die specimens and the inlay casting waxes. The inlay casting waxes tested were Starwax (Dentaurum), Unterziehwachs (Bredent), SU Esthetic wax (Schuler), and Sculpturing wax (Renfert). The marginal opening of the waxes was measured with a stereomicroscope on high-strength stone dies and on titanium and zirconia abutments. Photographic images were obtained, and the mean marginal opening for each specimen was calculated. A total of 1440 measurements were made. Wetting between die materials and waxes was determined after fabricating stone, titanium, and zirconia rectangular specimens. A calibrated pipette was used to place a drop of molten wax onto each specimen. The contact angle was calculated with software after an image of each specimen had been made with a digital camera. Collected data were subjected to a 2-way analysis of variance (α=.05). Any association between marginal accuracy and wetting of different materials was found by using the Pearson correlation. The wax factor had a statistically significant effect both on the marginal discrepancy (F=158.31, P<.001) and contact angle values (F=68.09, P<.001). A statistically significant effect of the die material factor both on the marginal adaptation (F=503.47, P<.001) and contact angle values (F=585.02, P<.001) was detected. A significant correlation between the marginal accuracy and the contact angle values (Pearson=0.881, P=.01) was also found. Stone dies provided wax copings with the best marginal integrity, followed by titanium and zirconia abutments. Unterziehwachs (Bredent), wax produced the best marginal adaptation on different die materials. A significant correlation was found

Tectonic microplates in a wax model of sea-floor spreading

International Nuclear Information System (INIS)

Katz, Richard F; Ragnarsson, Rolf; Bodenschatz, Eberhard

2005-01-01

Rotating, growing microplates are observed in a wax analogue model of sea-floor spreading. Wax microplates are kinematically similar to sea-floor tectonic microplates in terms of spreading rate and growth rate. Furthermore, their spiral pseudofault geometry is quantitatively consistent with Schouten's oceanic microplate model. These results suggest that Schouten's edge-driven microplate model captures the kinematics of tectonic microplate evolution on Earth. Based on the wax observations, a theory for the nucleation of overlapping spreading centres, the precursors of tectonic microplates, is developed

Epicuticular wax on stomata of damaged silver fir trees (Abies alba Mili.

Directory of Open Access Journals (Sweden)

Tomislav Bačić

2011-01-01

Full Text Available Condition of epistomatal wax on the abaxial surface of the current and previous-year needles of damaged silver fir trees (Abies alba Mill., both from the polluted Risnjak and "clean" Donja Dobra sites in Gorski Kotar region, both influenced by pollutants coming from Europe, during two years, three times a year, were examined with Scanning Electron Microscope. In the course of time the wax tubules on the epistomatal rims of stomata in polluted, but also in "clean" needles surface, become fused and agglomerated rapidly to various extents of morphologically different types of amorphous wax crusts, primarily compact and particulate ones. This process begins very early, especially in polluted Risnjak site, and may be interpreted as a possible result of air pollution. However, the recrystalization, or production of new tubules, also appears relatively quickly in mostly cases. Quantitative estimations indicate a very large total amount of amorphous wax crusts in the current-year needles, and a very high percentage of the same wax in previous-year needles. Amorphous wax crusts cover stomatal pores, as well as the rims, disturbing the normal gas exchange. Statistically there is a signicant tendency of increase in wax degradation in the needles of the polluted site in comparison with those of the unpolluted one, but there is an insignificant wax degradation among the needles of damaged trees within each site. These results confirmed most of the research done in our preliminary report.

Biochemical response of sweet potato to bemul-wax coating ...

African Journals Online (AJOL)

Sweet potato (Ipomoea batatas Linn) tuber is a very nutritious but highly perishable crop that is subject to high wastages due to non-availability of appropriate storage techniques. This work assessed the effectiveness of treating the tubers with calcium chloride dip (CCD), bemul-wax (B-wax) and their combinations ...

Unheimlich. From Wax Figures to the Uncanny Valley

Directory of Open Access Journals (Sweden)

Pietro Conte

2012-01-01

Full Text Available In his pioneering History of Portraiture in Wax, Julius von Schlosser traced back the age-old history of a material which at that time seemed to be already antiquated, if not obsolete. Wax sculptures were rejected and ousted from art history because of their excessive similarity and adherence to models. One hundred years later, however, hyperrealism got its revenge with Maurizio Cattelan’s celebrated hanging children. Moving from that controversial artwork and focusing on the heated polemics over it, my paper will address the question of the well-known Unheimlichkeit of wax figures, investigated by Ernst Jentsch and Sigmund Freud in the early Twentieth Century and nowadays becoming increasingly topical thanks to the recent debate about the existence and nature of the so called Uncanny Valley.

Effects of cuticular wax on the postharvest quality of blueberry fruit.

Science.gov (United States)

Chu, Wenjing; Gao, Haiyan; Chen, Hangjun; Fang, Xiangjun; Zheng, Yonghua

2018-01-15

The blueberry fruit has a light-blue appearance because its blue-black skin is covered with a waxy bloom. This layer is easily damaged or removed during fruit harvesting and postharvest handling. We investigated the effects of wax removal on the postharvest quality of blueberry fruit and their possible mechanisms. The removal of natural wax on the fruit was found to accelerate the postharvest water loss and decay, reduce the sensory and nutritional qualities, and shorten the shelf-life. Wax removal decreased the activities of antioxidant enzymes and contents of antioxidants, and accelerated accumulation of ROS and lipid peroxidation, especially at the later period of storage. Moreover, the organellar membrane structure was disrupted in fruit with wax removed. These results indicate that cuticular wax plays an important role in maintaining the postharvest quality and delaying fruit senescence. The results should improve our understanding for better preservation of postharvest quality of blueberry fruit. Copyright © 2017 Elsevier Ltd. All rights reserved.

Composition and morphology of cuticular wax in blueberry (Vaccinium spp.) fruits.

Science.gov (United States)

Chu, Wenjing; Gao, Haiyan; Cao, Shifeng; Fang, Xiangjun; Chen, Hangjun; Xiao, Shangyue

2017-03-15

The chemical composition and morphology of cuticular wax in mature fruit of nine blueberry cultivars were investigated using gas chromatography-mass spectrometry (GC-MS) and scanning electron microscope (SEM). Triterpenoids and β-diketones were the most prominent compounds, accounting for on average 64.2% and 16.4% of the total wax, respectively. Ursolic or oleanolic acid was identified as the most abundant triterpenoids differing in cultivars. Two β-diketones, hentriacontan-10,12-dione and tritriacontan-12,14-dione, were detected in cuticular wax of blueberry fruits for the first time. Notably, hentriacontan-10,12-dione and tritriacontan-12,14-dione were only detected in highbush (V. corymbosum) and rabbiteye (V. ashei) blueberries, respectively. The results of SEM showed that a large amount of tubular wax deposited on the surface of blueberry fruits. There was no apparent difference in wax morphology among the nine cultivars. Copyright © 2016 Elsevier Ltd. All rights reserved.

Characterization of a plant leaf cuticle model wax, phase behaviour of model wax–water systems

International Nuclear Information System (INIS)

Fagerström, Anton; Kocherbitov, Vitaly; Westbye, Peter; Bergström, Karin; Mamontova, Varvara; Engblom, Johan

2013-01-01

Highlights: • Four individual crystalline phases were discovered in the model wax–water system. • Eutectic melting occurred in both dry and hydrated model wax. • The total transition enthalpy is smaller for the cuticle wax than for the model wax. • Water has a large plasticizing effect on cuticle wax. • The thermotropic transitions of model wax fit in the window of extracted leaf waxes. - Abstract: We investigated the thermotropic phase behaviour of plant leaf intracuticular wax and two representatives of its main components, 1-docosanol (C 22 H 45 OH) and dotriacontane (C 32 H 66 ), in dry and hydrated state. One objective was to obtain a model wax, which can be used to estimate formulations effects on cuticle diffusivity in vitro. The two wax components were chosen based on results from Gas Chromatography coupled to Mass Spectrometry analysis of cuticular wax. The wax was extracted from Clivia Miniata Regel leaves and contained 68% primary alcohols (C 16 –C 32 ) and 16% n-alkanes (C 21 –C 33 ). Differential Scanning Calorimetry, Polarized Light Microscopy and Small- and Wide Angle X-ray Diffraction were used to characterize the cuticular extract and the phase behaviour of the C 22 H 45 OH/C 32 H 66 /H 2 O model system. Four individual crystalline phases were discovered in the model wax–water system and eutectic melting occurred in both dry and hydrated state. The thermotropic transitions of the model wax occur within the broader transition region of the extracted leaf wax

Methods for separating boron from borated paraffin wax and its determination by ion chromatography

International Nuclear Information System (INIS)

Jeyakumar, S.

2015-01-01

Boron compounds are found to be useful in shielding against high-energy neutrons. In radiotherapy treatments, in order to protect occupational workers and patients from the undesirable neutron and gamma doses, paraffin wax containing B 4 C/boric acid is used. Low-level borate wastes generated from the nuclear power plants have been immobilized with paraffin wax using a concentrate waste drying system (CWDS). Borated paraffin waxes are prepared by mixing calculated amounts of either boric acid or boron carbide with the molten wax. This necessitates the determination of boron at different locations in order to check the homogeneous distribution of B over the borated wax. The determination of boron in nuclear materials is inevitable due to its high neutron absorption cross section. For the determination of boron in borated waxes, not many methods have been reported. A method based on the pyrohydrolysis extraction of boron and its quantification with ion chromatography was proposed for paraffin waxes borated with H 3 BO 3 and B 4 C. The B 4 C optimum pyrohydrolysis conditions were identified. Wax samples were mixed with U 3 O 8 , which prevents the sample from flare up, and also accelerates the extraction of boron. Pyrohydrolysis was carried out with moist O 2 at 950℃ for 60 and 90 min for wax with H 3 BO 3 and wax with B 4 C, respectively. Two simple methods of separation based on alkali extraction and melting wax in alkali were also developed exclusively for wax with H 3 BO 3 . In all the separations, the recovery of B was above 98%. During IC separation, B was separated as boron-mannitol anion complex. Linear calibration was obtained between 0.1 and 50 ppm of B, and LOD was calculated as 5 ppb (S/N=3). The reproducibility was better than 5% (RSD)

Problems in interpreting effects of air pollutants on spruce epicuticular waxes

International Nuclear Information System (INIS)

Bermadinger-Stabentheiner, E.

1994-01-01

Spruce needles are covered with rod-like crystals, which also fill the antechambers of the stomata with a dense meshwork. The scanning electron microscope (SEM) is very useful for studying epicuticular wax structure; with no intricate or laborious preparation, it is possible to obtain valuable information about the needle surface. Because the epicuticular wax layer forms a barrier between the plant and its environment, all influences that reach the surface from outside impact on this layer and, therefore, changes in epicuticular wax structure serve as diagnostic criteria for damage caused by air pollutants. This pollution influence begins as fusion of wax rods at the tips and results finally in total loss of the crystalline structure. Despite the simplicity of SEM investigations, alterations (artefacts) can occur to wax structures that may be confused with alterations caused by air pollutants (i.e., a too dense layer of twigs and needles, or careless handling with tweezers, results in mechanical damage that often influences the entire surface). Overheating occurring during transport or preparation and/or incorrect storage also produce artefacts. If the occurrence of such artefacts is taken into consideration, several contradictory interpretations of effects of air pollutants on epicuticular waxes can be explained. (orig.)

Influence of Different Waxes on the Physical Properties of Linear ...

African Journals Online (AJOL)

NJD

2005-12-22

Dec 22, 2005 ... viscosity of a polymer melt. In many instances it ... amounts of different waxes on the viscosity (melt flow) of ..... Since the MFI is a direct measure of the viscosity .... melt flow index increasing with increasing wax content. There.

Wax Impaction in Nigerian School Children. | Eziyi | East and ...

African Journals Online (AJOL)

Background: Impacted wax has been classified as an ear disease. It can cause pain, itching, tinnitus hearing loss or otitis externa. The prevalence of cerumen impaction varies. The aim of this study was to determine the prevalence of impacted ear wax in primary school children and to determine, if there is any association ...

Oil-structuring characterization of natural waxes in canola oil oleogels: Rheological, thermal, and oxidative properties

Science.gov (United States)

Natural waxes (candelilla wax, carnauba wax, and beeswax) were utilized as canola oil structurants to produce oleogels and their physicochemical properties were evaluated from rheological, thermal, and oxidative points of view. The oleogels with candelilla wax exhibited the highest hardness, followe...

Characterization of a plant leaf cuticle model wax, phase behaviour of model wax–water systems

Energy Technology Data Exchange (ETDEWEB)

Fagerström, Anton, E-mail: anton.fagerstrom@mah.se [Biomedical Science, Faculty of Health and Society, Malmö University, Malmö (Sweden); Kocherbitov, Vitaly [Biomedical Science, Faculty of Health and Society, Malmö University, Malmö (Sweden); Westbye, Peter; Bergström, Karin [Agro Applications Europe, AkzoNobel Surface Chemistry AB, Stenungsund (Sweden); Mamontova, Varvara [Ecological and Chemical Research, St. Petersburg Scientific Research Center for Ecological Safety, Russian Academy of Sciences, St. Petersburg (Russian Federation); Engblom, Johan [Biomedical Science, Faculty of Health and Society, Malmö University, Malmö (Sweden)

2013-11-10

Highlights: • Four individual crystalline phases were discovered in the model wax–water system. • Eutectic melting occurred in both dry and hydrated model wax. • The total transition enthalpy is smaller for the cuticle wax than for the model wax. • Water has a large plasticizing effect on cuticle wax. • The thermotropic transitions of model wax fit in the window of extracted leaf waxes. - Abstract: We investigated the thermotropic phase behaviour of plant leaf intracuticular wax and two representatives of its main components, 1-docosanol (C{sub 22}H{sub 45}OH) and dotriacontane (C{sub 32}H{sub 66}), in dry and hydrated state. One objective was to obtain a model wax, which can be used to estimate formulations effects on cuticle diffusivity in vitro. The two wax components were chosen based on results from Gas Chromatography coupled to Mass Spectrometry analysis of cuticular wax. The wax was extracted from Clivia Miniata Regel leaves and contained 68% primary alcohols (C{sub 16}–C{sub 32}) and 16% n-alkanes (C{sub 21}–C{sub 33}). Differential Scanning Calorimetry, Polarized Light Microscopy and Small- and Wide Angle X-ray Diffraction were used to characterize the cuticular extract and the phase behaviour of the C{sub 22}H{sub 45}OH/C{sub 32}H{sub 66}/H{sub 2}O model system. Four individual crystalline phases were discovered in the model wax–water system and eutectic melting occurred in both dry and hydrated state. The thermotropic transitions of the model wax occur within the broader transition region of the extracted leaf wax.

Anatomical models and wax Venuses: art masterpieces or scientific craft works?

Science.gov (United States)

Ballestriero, R

2010-02-01

The art of wax modelling has an ancient origin but rose to prominence in 14th century Italy with the cult of votive artefacts. With the advent of Neoclassicism this art, now deemed repulsive, continued to survive in a scientific environment, where it flourished in the study of normal and pathological anatomy, obstetrics, zoology and botany. The achievement of having originated the creation of anatomical models in coloured wax must be ascribed to a joint effort undertaken by the Sicilian wax modeller Gaetano Giulio Zumbo and the French surgeon Guillaume Desnoues in the late 17th century. Interest in anatomical wax models spread throughout Europe during the 18th century, first in Bologna with Ercole Lelli, Giovanni Manzolini and Anna Morandi, and then in Florence with Felice Fontana and Clemente Susini. In England, the art of anatomical ceroplastics was brought to London from Florence by the sculptor Joseph Towne. Throughout the centuries many anatomical artists preferred this material due to the remarkable mimetic likeness obtained, far surpassing any other material. Independent of the material used, whether wood, wax or clay, anatomical models were always considered merely craft works confined to hospitals or faculties of medicine and have survived to this day only because of their scientific interest. Italian and English waxes are stylistically different but the remarkable results obtained by Susini and Towne, and the fact that some contemporary artists are again representing anatomical wax bodies in their works, makes the border that formerly separated art and craft indistinguishable.

Sintering of wax for controlling release from pellets

OpenAIRE

Singh, Reena; Poddar, S. S.; Chivate, Amit

2007-01-01

The purpose of the present study was to investigate incorporation of hydrophobic (ie, waxy) material into pellets using a thermal sintering technique and to evaluate the pellets in vitro for controlled release. Pellets prepared by extrusion-spheronization technology were formulated with a water-soluble drug, microcrystalline cellulose, and carnauba wax. Powdered carnauba wax (4%–20%) prepared by grinding or by emulsification was studied with an attempt to retard the drug release. The inclusio...

Development of formulations and processes to incorporate wax oleogels in ice cream.

Science.gov (United States)

Zulim Botega, Daniele C; Marangoni, Alejandro G; Smith, Alexandra K; Goff, H Douglas

2013-12-01

The objective of this study was to investigate the influence of emulsifiers, waxes, fat concentration, and processing conditions on the application of wax oleogel to replace solid fat content and create optimal fat structure in ice cream. Ice creams with 10% or 15% fat were formulated with rice bran wax (RBW), candelilla wax (CDW), or carnauba wax (CBW) oleogels, containing 10% wax and 90% high-oleic sunflower oil. The ice creams were produced using batch or continuous freezing processes. Transmission electron microscopy (TEM) and cryo-scanning electron microscopy were used to evaluate the microstructure of ice cream and the ultrastructure of oleogel droplets in ice cream mixes. Among the wax oleogels, RBW oleogel had the ability to form and sustain structure in 15% fat ice creams when glycerol monooleate (GMO) was used as the emulsifier. TEM images revealed that the high degree of fat structuring observed in GMO samples was associated with the RBW crystal morphology within the fat droplet, which was characterized by the growth of crystals at the outer edge of the droplet. Continuous freezing improved fat structuring compared to batch freezing. RBW oleogels established better structure compared to CDW or CBW oleogels. These results demonstrate that RBW oleogel has the potential to develop fat structure in ice cream in the presence of GMO and sufficiently high concentrations of oleogel. © 2013 Institute of Food Technologists®

Bad Breath

Science.gov (United States)

... cabbage. And of course smoking causes its own bad smell. Some diseases and medicines can cause a specific breath odor. Having good dental habits, like brushing and flossing regularly, help fight bad ...

Physico-chemical properties and efficacy of silk fibroin fabric coated with different waxes as wound dressing.

Science.gov (United States)

Kanokpanont, Sorada; Damrongsakkul, Siriporn; Ratanavaraporn, Juthamas; Aramwit, Pornanong

2013-04-01

Silk fibroin (SF) has been widely used as a wound dressing material due to its suitable physical and biological characteristics. In this study, a non-adhesive wound dressing which applies to cover the wound surface as an absorbent pad that would absorb wound fluid while accelerate wound healing was developed. The modification of SF fabrics by wax coating was purposed to prepare the non-adhesive wound dressing that is required in order to minimize pain and risk of repeated injury. SF woven fabrics were coated with different types of waxes including shellac wax, beeswax, or carnauba wax. Physical and mechanical properties of the wax-coated SF fabrics were characterized. It was clearly observed that all waxes could be successfully coated on the SF fabrics, possibly due to the hydrophobic interactions between hydrophobic domains of SF and waxes. The wax coating improved tensile modulus and percentage of elongation of the SF fabrics due to the denser structure and the thicker fibers coated. The in vitro degradation study demonstrated that all wax-coated SF fabrics remained up to 90% of their original weights after 7 weeks of incubation in lysozyme solution under physiological conditions. The wax coating did not affect the degradation behavior of the SF fabrics. A peel test of the wax-coated SF fabrics was carried out in the partial- and full-thickness wounds of porcine skin in comparison to that of the commercial wound dressing. Any wax-coated SF fabrics were less adhesive than the control, as confirmed by less number of cells attached and less adhesive force. This might be that the wax-coated SF fabrics showed the hydrophobic property, allowing the loosely adherence to the hydrophilic wound surface. In addition, the in vivo biocompatibility test of the wax-coated SF fabrics was performed in Sprague-Dawley rats with subcutaneous model. The irritation scores indicated that the carnauba wax-coated SF fabric was not irritant while the shellac wax or beeswax-coated SF

Marginal Integrity of Glass Ionomer and All Ceramic Restorations

Science.gov (United States)

2016-06-01

that would be expected with daily food and beverage intake. And no toothbrush or flossing abrasion occurred. Future studies could incorporate... management of dental caries. Quintessence International, 33(6), 427-432. 65. Frencken J.E., Peters M.C., Manton D.J., Leal S.C., Gordan V.V., Eden E...2012). Minimal intervention dentistry for managing dental caries - a review: Report of a FDI task group. International Dental Journal, 62(5), 223

Synthesis of oleyl oleate wax esters in Arabidopsis thaliana and Camelina sativa seed oil.

Science.gov (United States)

Iven, Tim; Hornung, Ellen; Heilmann, Mareike; Feussner, Ivo

2016-01-01

Seed oil composed of wax esters with long-chain monoenoic acyl moieties represents a high-value commodity for industry. Such plant-derived sperm oil-like liquid wax esters are biodegradable and can have excellent properties for lubrication. In addition, wax ester oil may represent a superior substrate for biodiesel production. In this study, we demonstrate that the low-input oil seed crop Camelina sativa can serve as a biotechnological platform for environmentally benign wax ester production. Two biosynthetic steps catalysed by a fatty alcohol-forming acyl-CoA reductase (FAR) and a wax ester synthase (WS) are sufficient to achieve wax ester accumulation from acyl-CoA substrates. To produce plant-derived sperm oil-like liquid wax esters, the WS from Mus musculus (MmWS) or Simmondsia chinensis (ScWS) were expressed in combination with the FAR from Mus musculus (MmFAR1) or Marinobacter aquaeolei (MaFAR) in seeds of Arabidopsis thaliana and Camelina sativa. The three analysed enzyme combinations Oleo3:mCherry:MmFAR1∆c/Oleo3:EYFP:MmWS, Oleo3:mCherry:MmFAR1∆c/ScWS and MaFAR/ScWS showed differences in the wax ester molecular species profiles and overall biosynthetic performance. By expressing MaFAR/ScWS in Arabidopsis or Camelina up to 59% or 21% of the seed oil TAGs were replaced by wax esters, respectively. This combination also yielded wax ester molecular species with highest content of monounsaturated acyl moieties. Expression of the enzyme combinations in the Arabidopsis fae1 fad2 mutant background high in oleic acid resulted in wax ester accumulation enriched in oleyl oleate (18:1/18:1 > 60%), suggesting that similar values may be obtained with a Camelina high oleic acid line. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

QUALITATIVE ANALYSIS METHOD OF DETECTION OF WAX CONTENT IN GORENGAN USING SMARTPHONE

Directory of Open Access Journals (Sweden)

Yulia Yulia

2018-05-01

Full Text Available Wax is one of the compounds that can be misused to be added to Gorengan, Indonesian fritter, to keep them crispy. Gorengan containing wax is difficult to identify visually, so a quick and easy method of detecting wax content is required. The purpose of this research is to develop and evaluate the analytical performance of detecting wax content in gorengan using smartphone. Gorengan sample was dissolved with hexane and then added reagent that will give discoloration followed by analysis using smartphone. Some analysis performance parameters were evaluated in terms of linearity and detection limit, qualitative analysis capability, precision, and selectivity test. The developed method was also applied in some gorengan samples. The result shows that the detection of wax content in gorengan can be conducted by using reagent consisting of NaOH, Schift, and curcumin (1 : 2 : 2. Performance analysis shows that the linearity measurement at concentration between 10% and 25% has correlation coefficient (r of 0.9537 with detection limit at concentration of 2% and precision (%RSD less than 3%. The developed method can be applied for the detection of wax content in gorengan in the market.

An Empirical Verification of a-priori Learning Models on Mailing Archives in the Context of Online Learning Activities of Participants in Free\\Libre Open Source Software (FLOSS) Communities

Science.gov (United States)

Mukala, Patrick; Cerone, Antonio; Turini, Franco

2017-01-01

Free\\Libre Open Source Software (FLOSS) environments are increasingly dubbed as learning environments where practical software engineering skills can be acquired. Numerous studies have extensively investigated how knowledge is acquired in these environments through a collaborative learning model that define a learning process. Such a learning…

Purification of a jojoba embryo wax synthase, cloning of its cDNA, and production of high levels of wax in seeds of transgenic arabidopsis.

Science.gov (United States)

Lardizabal, K D; Metz, J G; Sakamoto, T; Hutton, W C; Pollard, M R; Lassner, M W

2000-03-01

Wax synthase (WS, fatty acyl-coenzyme A [coA]: fatty alcohol acyltransferase) catalyzes the final step in the synthesis of linear esters (waxes) that accumulate in seeds of jojoba (Simmondsia chinensis). We have characterized and partially purified this enzyme from developing jojoba embryos. A protein whose presence correlated with WS activity during chromatographic fractionation was identified and a cDNA encoding that protein was cloned. Seed-specific expression of the cDNA in transgenic Arabidopsis conferred high levels of WS activity on developing embryos from those plants. The WS sequence has significant homology with several Arabidopsis open reading frames of unknown function. Wax production in jojoba requires, in addition to WS, a fatty acyl-CoA reductase (FAR) and an efficient fatty acid elongase system that forms the substrates preferred by the FAR. We have expressed the jojoba WS cDNA in Arabidopsis in combination with cDNAs encoding the jojoba FAR and a beta-ketoacyl-CoA synthase (a component of fatty acid elongase) from Lunaria annua. (13)C-Nuclear magnetic resonance analysis of pooled whole seeds from transgenic plants indicated that as many as 49% of the oil molecules in the seeds were waxes. Gas chromatography analysis of transmethylated oil from individual seeds suggested that wax levels may represent up to 70% (by weight) of the oil present in those seeds.

The MIEL1 E3 Ubiquitin Ligase Negatively Regulates Cuticular Wax Biosynthesis in Arabidopsis Stems.

Science.gov (United States)

Lee, Hong Gil; Kim, Juyoung; Suh, Mi Chung; Seo, Pil Joon

2017-07-01

Cuticular wax is an important hydrophobic layer that covers the plant aerial surface. Cuticular wax biosynthesis is shaped by multiple layers of regulation. In particular, a pair of R2R3-type MYB transcription factors, MYB96 and MYB30, are known to be the main participants in cuticular wax accumulation. Here, we report that the MYB30-INTERACTING E3 LIGASE 1 (MIEL1) E3 ubiquitin ligase controls the protein stability of the two MYB transcription factors and thereby wax biosynthesis in Arabidopsis. MIEL1-deficient miel1 mutants exhibit increased wax accumulation in stems, with up-regulation of wax biosynthetic genes targeted by MYB96 and MYB30. Genetic analysis reveals that wax accumulation of the miel1 mutant is compromised by myb96 or myb30 mutation, but MYB96 is mainly epistatic to MIEL1, playing a predominant role in cuticular wax deposition. These observations indicate that the MIEL1-MYB96 module is important for balanced cuticular wax biosynthesis in developing inflorescence stems. © The Author 2017. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Inverse gradients in leaf wax δD and δ13C values along grass blades of Miscanthus sinensis: implications for leaf wax reproduction and plant physiology.

Science.gov (United States)

Gao, Li; Huang, Yongsong

2013-06-01

Compound specific hydrogen and carbon isotopic ratios of higher plant leaf waxes have been extensively used in paleoclimate and paleoenvironmental reconstructions. However, studies so far have focused on the comparison of leaf wax isotopic differences in bulk leaf samples between different plant species. We sampled three different varieties of tall grasses (Miscanthus sinensis) in six segments from base to tip and determined hydrogen and carbon isotopic ratios of leaf waxes, as well as hydrogen and oxygen isotopic ratios of leaf water samples. We found an increasing, base-to-tip hydrogen isotopic gradient along the grass blades that can probably be attributed to active leaf wax regeneration over the growth season. Carbon isotopic ratios, on the other hand, show opposite trends to hydrogen isotopic ratios along the grass blades, which may reflect different photosynthetic efficiencies at different blade locales.

with gingivitis and periodontitis referring Resalat Dental Clinic, Chaleshtor in 2015

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MS Khafari ghosheh

2017-05-01

Full Text Available Abstract   Background & aim: Entamoeba gingivalis and Trichomonas tenax are oral protozoa that could cause periodontitis and gingivitis. The present study was done to determine the prevalence of these two protozoa in people over 14 years with periodontitis and gingivitis.   Methods: In this descriptive, cross-sectional study, 540 patients referring Resalat Dental Clinic, Shahrekord were enrolled and assigned in two groups of 270 patients with periodontitis and gingivitis and270 healthy individuals. The prepared specimens were examined by extensive wet procedures, Gimsa staining and Trichorom staining. Data were analyzed by chi-square, Fisher’s exact test, and logistic regression in SPSSv.20.   Results: No E. gingivalis- and T. tenax-positive cases were seen in the healthy group. The prevalence of E. gingivalis and T. tenax was obtained 3% by extensive wet procedure, 1.9% by Trichoderma staining, and 0.7% by Giemsa staining respectively. By logistic regression model, none of variables of age, gender, place of residence, smoking, tooth brushing, flossing, and oral PH were associated protozoan infection of E. gingivalis and T. tenax (P>0.05. Conclusion: In patients with periodontitis and gingivitis referred to the dental clinic, parasitic infections were attenuated to gingivialis and trichomoniasis vaginalis, and possibly other non-parasitic agents, including bacteria or other microorganisms, may play a role.    

Analysis of the constituents in jojoba wax used as a food additive by LC/MS/MS.

Science.gov (United States)

Tada, Atsuko; Jin, Zhe-Long; Sugimoto, Naoki; Sato, Kyoko; Yamazaki, Takeshi; Tanamoto, Kenichi

2005-10-01

Jojoba wax is a natural gum base used as a food additive in Japan, and is obtained from jojoba oil with a characteristically high melting point. Although the constituents of jojoba oil have been reported, the quality of jojoba wax used as a food additive has not yet been clarified. In order to evaluate its quality as a food additive and to obtain basic information useful for setting official standards, we investigated the constituents and their concentrations in jojoba wax. LC/MS analysis of the jojoba wax showed six peaks with [M+H]+ ions in the range from m/z 533.6 to 673.7 at intervals of m/z 28. After isolation of the components of the four main peaks by preparative LC/MS, the fatty acid and long chain alcohol moieties of the wax esters were analyzed by methanolysis and hydrolysis, followed by GC/MS. The results indicated that the main constituents in jojoba wax were various kinds of wax esters, namely eicosenyl octadecenoate (C20:1-C18:1) (1), eicosenyl eicosenoate (C20:1-C20:1) (II), docosenyl eicosenoate (C22:1-C20:1) (III), eicosenyl docosenoate (C20:1-C22:1) (IV) and tetracosenyl eiosenoate (C24:1-C20:1) (V). To confirm and quantify the wax esters in jojoba wax directly, LC/MS/MS analysis was performed. The product ions corresponding to the fatty acid moieties of the wax esters were observed, and by using the product ions derived from the protonated molecular ions of wax esters the fatty acid moieties were identified by MRM analysis. The concentrations of the wax esters I, II and III, in jojoba wax were 5.5, 21.4 and 37.8%, respectively. In summary, we clarified the main constituents of jojoba wax and quantified the molecular species of the wax esters without hydrolysis by monitoring their product ions, using a LC/MS/MS system.

SEPARATION OF FISCHER-TROPSCH WAX PRODUCTS FROM ULTRAFINE IRON CATALYST PARTICLES

Energy Technology Data Exchange (ETDEWEB)

James K. Neathery; Gary Jacobs; Burtron H. Davis

2004-03-31

In this reporting period, a fundamental filtration study was started to investigate the separation of Fischer-Tropsch Synthesis (FTS) liquids from iron-based catalyst particles. Slurry-phase FTS in slurry bubble column reactor systems is the preferred mode of production since the reaction is highly exothermic. Consequently, heavy wax products must be separated from catalyst particles before being removed from the reactor system. Achieving an efficient wax product separation from iron-based catalysts is one of the most challenging technical problems associated with slurry-phase FTS. The separation problem is further compounded by catalyst particle attrition and the formation of ultra-fine iron carbide and/or carbon particles. Existing pilot-scale equipment was modified to include a filtration test apparatus. After undergoing an extensive plant shakedown period, filtration tests with cross-flow filter modules using simulant FTS wax slurry were conducted. The focus of these early tests was to find adequate mixtures of polyethylene wax to simulate FTS wax. Catalyst particle size analysis techniques were also developed. Initial analyses of the slurry and filter permeate particles will be used by the research team to design improved filter media and cleaning strategies.

Prediction of wax buildup in 24 inch cold, deep sea oil loading line

Energy Technology Data Exchange (ETDEWEB)

Asperger, R.G.; Sattler, R.E.; Tolonen, W.J.; Pitchford, A.C.

1981-10-01

When designing pipelines for cold environments, it is important to know how to predict potential problems due to wax deposition on the pipeline's inner surface. The goal of this work was to determine the rate of wax buildup and the maximum, equlibrium wax thickness for a North Sea field loading line. The experimental techniques and results used to evaluate the waxing potential of the crude oil (B) are described. Also, the theoretic model which was used for predicting the maximum wax deposit thickness in the crude oil (B) loading pipeline at controlled temperatures of 40 F (4.4 C) and 100 F (38 C), is illustrated. Included is a recommendation of a procedure for using hot oil at the end of a tanker loading period in order to dewax the crude oil (B) line. This technique would give maximum heating of the pipeline and should be followed by shutting the hot oil into the pipeline at the end of the loading cycle which will provide a hot oil soaking to help soften existing wax. 14 references.

Bad Breath

Science.gov (United States)

... garlic, onions, cheese, orange juice, and soda poor dental hygiene (say: HI-jeen), meaning not brushing and flossing regularly smoking and other tobacco use Poor oral hygiene leads to bad breath because when food particles ...

Laboratory Deposition Apparatus to Study the Effects of Wax Deposition on Pipe Magnetic Field Leakage Signals

Directory of Open Access Journals (Sweden)

Karim Mohd Fauzi Abd

2014-07-01

Full Text Available Accurate technique for wax deposition detection and severity measurement on cold pipe wall is important for pipeline cleaning program. Usually these techniques are validated by conventional techniques on laboratory scale wax deposition flow loop. However conventional techniques inherent limitations and it is difficult to reproduce a predetermine wax deposit profile and hardness at designated location in flow loop. An alternative wax deposition system which integrates modified pour casting method and cold finger method is presented. This system is suitable to reproduce high volume of medium hard wax deposit in pipe with better control of wax deposit profile and hardness.

Effect of waste wax and chain structure on the mechanical and physical properties of polyethylene

Directory of Open Access Journals (Sweden)

M.A. AlMaadeed

2015-05-01

The wax dispersion in the matrix strongly depends on the percentage of wax added to the polymer and the molecular structure of the polymer. It was found that increasing the wax content enhances the phase separation. LDPE undergoes less phase separation due to its highly branched structure composed of a network of short and long chain branches. The wax has no pronounced plasticising effect on the polymer. This is clearly manifested in LDPE as no change in the melting temperature occurred. LLDPE and HDPE were slightly affected by a high concentration of wax (30% and 40%. This is due to the non-uniform distribution of short chain branching along the LLDPE and HDPE main chains, which can interact with the wax structure.

Rheological profiling of organogels prepared at critical gelling concentrations of natural waxes in a triacylglycerol solvent.

Science.gov (United States)

Patel, Ashok R; Babaahmadi, Mehrnoosh; Lesaffer, Ans; Dewettinck, Koen

2015-05-20

The aim of this study was to use a detailed rheological characterization to gain new insights into the gelation behavior of natural waxes. To make a comprehensive case, six natural waxes (differing in the relative proportion of chemical components: hydrocarbons, fatty alcohols, fatty acids, and wax esters) were selected as organogelators to gel high-oleic sunflower oil. Flow and dynamic rheological properties of organogels prepared at critical gelling concentrations (Cg) of waxes were studied and compared using drag (stress ramp and steady flow) and oscillatory shear (stress and frequency sweeps) tests. Although, none of the organogels satisfied the rheological definition of a "strong gel" (G″/G' (ω) ≤ 0.1), on comparing the samples, the strongest gel (highest critical stress and dynamic, apparent, and static yield stresses) was obtained not with wax containing the highest proportion of wax esters alone (sunflower wax, SFW) but with wax containing wax esters along with a higher proportion of fatty alcohols (carnauba wax, CRW) although at a comparatively higher Cg (4%wt for latter compared to 0.5%wt for former). As expected, gel formation by waxes containing a high proportion of lower melting fatty acids (berry, BW, and fruit wax, FW) required a comparatively higher Cg (6 and 7%wt, respectively), and in addition, these gels showed the lowest values for plateau elastic modulus (G'LVR) and a prominent crossover point at higher frequency. The gelation temperatures (TG'=G″) for all the studied gels were lower than room temperature, except for SFW and CRW. The yielding-type behavior of gels was evident, with most gels showing strong shear sensitivity and a weak thixotropic recovery. The rheological behavior was combined with the results of thermal analysis and microstructure studies (optical, polarized, and cryo-scanning electron microscopy) to explain the gelation properties of these waxes.

Subchronic feeding study of carnauba wax in beagle dogs.

Science.gov (United States)

Parent, R A; Cox, G E; Babish, J G; Gallo, M A; Hess, F G; Becci, P J

1983-02-01

Carnauba wax fed at levels of 0.1, 0.3 and 1% in the diet to beagle dogs for 28 wk did not produce evidence of toxicity or pathological effects. Body weight gain, food consumption, clinical chemical, haematological, and urine analysis data, and organ weights of animals fed carnauba wax were comparable with those of control animals. Ophthalmic, gross and histopathological examinations revealed no significant treatment-related findings.

Electrochemical behaviors of wax-coated Li powder/Li 4Ti 5O 12 cells

Science.gov (United States)

Park, Han Eol; Seong, Il Won; Yoon, Woo Young

The wax-coated Li powder specimen was effectively synthesized using the drop emulsion technique (DET). The wax layer on the powder was verified by SEM, Focused Ion Beam (FIB), EDX and XPS. The porosity of a sintered wax-coated Li electrode was measured by linear sweep voltammetry (LSV) and compared with that of a bare, i.e., un-coated Li electrode. The electrochemical behavior of the wax-coated Li powder anode cell was examined by the impedance analysis and cyclic testing methods. The cyclic behavior of the wax-coated Li powder anode with the Li 4Ti 5O 12 (LTO) cathode cell was examined at a constant current density of 0.35 mA cm -2 with the cut-off voltages of 1.2-2.0 V at 25 °C. Over 90% of the initial capacity of the cell remained even after the 300th cycle. The wax-coated Li powder was confirmed to be a stable anode material.

Crystallography of waxes - an electron diffraction study of refined and natural products

Science.gov (United States)

Dorset, Douglas L.

1997-02-01

The crystal structure of four waxes has been investigated by electron crystallography. Two of these waxes, including a refined petroleum product (Gulfwax) and a material from lignite (montan wax), form well ordered crystals and their structure could be solved quantitatively from the observed 0022-3727/30/3/018/img1 diffraction patterns. As also found previously for simpler binary n-paraffin solid solutions, the average structure resembles that of a pure paraffin (e.g. n-0022-3727/30/3/018/img2) but with a Gaussian distribution of atomic occupancies near the chain ends to account for the statistical distribution of chain lengths within a lamella. Two other waxes from living organisms, South African bee honeycomb and the leaves of the Brazilian carnauba palm, are much less ordered, even though they share the same methylene subcell packing of the most crystalline parts of the previous materials. It appears that these waxes cannot fully separate into distinct lamellae, perhaps due to the presence of very long `tie' molecules, and are therefore `frustrated' crystal structures.

Wax Precipitation Modeled with Many Mixed Solid Phases

DEFF Research Database (Denmark)

Heidemann, Robert A.; Madsen, Jesper; Stenby, Erling Halfdan

2005-01-01

The behavior of the Coutinho UNIQUAC model for solid wax phases has been examined. The model can produce as many mixed solid phases as the number of waxy components. In binary mixtures, the solid rich in the lighter component contains little of the heavier component but the second phase shows sub......-temperature and low-temperature forms, are pure. Model calculations compare well with the data of Pauly et al. for C18 to C30 waxes precipitating from n-decane solutions. (C) 2004 American Institute of Chemical Engineers....

Accuracy of ringless casting and accelerated wax-elimination technique: a comparative in vitro study.

Science.gov (United States)

Prasad, Rahul; Al-Keraif, Abdulaziz Abdullah; Kathuria, Nidhi; Gandhi, P V; Bhide, S V

2014-02-01

The purpose of this study was to determine whether the ringless casting and accelerated wax-elimination techniques can be combined to offer a cost-effective, clinically acceptable, and time-saving alternative for fabricating single unit castings in fixed prosthodontics. Sixty standardized wax copings were fabricated on a type IV stone replica of a stainless steel die. The wax patterns were divided into four groups. The first group was cast using the ringless investment technique and conventional wax-elimination method; the second group was cast using the ringless investment technique and accelerated wax-elimination method; the third group was cast using the conventional metal ring investment technique and conventional wax-elimination method; the fourth group was cast using the metal ring investment technique and accelerated wax-elimination method. The vertical marginal gap was measured at four sites per specimen, using a digital optical microscope at 100× magnification. The results were analyzed using two-way ANOVA to determine statistical significance. The vertical marginal gaps of castings fabricated using the ringless technique (76.98 ± 7.59 μm) were significantly less (p castings fabricated using the conventional metal ring technique (138.44 ± 28.59 μm); however, the vertical marginal gaps of the conventional (102.63 ± 36.12 μm) and accelerated wax-elimination (112.79 ± 38.34 μm) castings were not statistically significant (p > 0.05). The ringless investment technique can produce castings with higher accuracy and can be favorably combined with the accelerated wax-elimination method as a vital alternative to the time-consuming conventional technique of casting restorations in fixed prosthodontics. © 2013 by the American College of Prosthodontists.

Modeling the hydration process of bean grains coated with carnauba wax

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Aline Almeida da Paixão

2017-08-01

Full Text Available Edible waxes are widely used to maintain foodstuff until they are consumed. However, some products may be subjected to industrial procedures, such as hydration, prior to their consumption. Hydration of a material is a complex process, which aims to reconstitute the original characteristics of a product when in contact with a liquid phase. An important agricultural product that requires this procedure is beans. Thus, the purpose of this work is to study the hydration process of beans (cultivar BRSMG Majestoso in different temperatures and concentrations of carnauba wax, which is applied on the product surface. Beans with initial moisture content of 0.2015, 0.1972 and 0.1745 (d.b. corresponding to treatments 0 (witness, 1 (wax diluted in water in the ratio 1:1, and 2 (carnauba wax, without dilution were used. Later, these samples were imbibed in distilled water at temperatures of 20, 30 and 40 ºC, for 15 h. The temperature and the carnauba wax influenced the water absorption rate. The Peleg model described satisfactory experimental data and the Mitscherlich model presented biased residual distribution. The constants C1 and C2 of the Peleg model exhibited opposite behaviors with increasing temperatures in the hydration process.

Caffeine and theobromine in epicuticular wax of Ilex paraguariensis A. St.-Hil.

Science.gov (United States)

Athayde, M L; Coelho, G C; Schenkel, E P

2000-12-01

Caffeine and theobromine were identified and quantified in leaf epicuticular waxes of Ilex paraguariensis A. St.-Hil. (Aquifoliaceae). The total epicuticular leaf wax content was ca. 0.5% on average of dry leaf weight. Epicuticular caffeine and theobromine contents varied from 0.16 to 127.6 microg/mg and from 0 to 9.5 microg/mg of wax, respectively. For some selected samples, the intracellular methylxanthine concentration was also determined. A positive correlation was found between inner and epicuticular caffeine contents.

Changes in Cuticular Wax Composition of Two Blueberry Cultivars during Fruit Ripening and Postharvest Cold Storage.

Science.gov (United States)

Chu, Wenjing; Gao, Haiyan; Chen, Hangjun; Wu, Weijie; Fang, Xiangjun

2018-03-21

Cuticular wax plays an important role for the quality of blueberry fruits. In this study, the cuticular wax composition of two blueberry cultivars, 'Legacy' ( Vaccinium corymbosum) and 'Brightwell' ( Vaccinium ashei), was examined during fruit ripening and postharvest cold storage. The results showed that wax was gradually deposited on the epidermis of blueberry fruits and the content of major wax compounds, except that for diketones, increased significantly during fruit ripening. The total wax content was 2-fold greater in 'Brightwell' blueberries than that in 'Legacy' blueberries during fruit ripening. The total wax content of both cultivars decreased during 30 days of storage at 4 °C, and the variation of cuticular wax composition was cultivar-dependent. The content of diketones decreased significantly in 'Legacy' blueberries, while the content of triterpenoids and aliphatic compounds showed different fold changes in 'Brightwell' blueberries after 30 days of storage at 4 °C. Overall, our study provided a quantitative and qualitative overview of cuticular wax compounds of blueberry fruits during ripening and postharvest cold storage.

Study of phase transition in hard microcrystalline waxes and wax blends by differential scanning calorimetry

Czech Academy of Sciences Publication Activity Database

Kumar, S.; Agrawal, K. M.; Khan, H. U.; Sikora, Antonín

2004-01-01

Roč. 22, 3 & 4 (2004), s. 337-345 ISSN 1091-6466 R&D Projects: GA AV ČR KSK4050111 Institutional research plan: CEZ:AV0Z4050913 Keywords : phase transition * hard microscrystalline waxes * differential scanning calorimetry Subject RIV: CD - Macromolecular Chemistry Impact factor: 0.312, year: 2004

Effects of sunflower wax coating on physicochemical changes of mangifera indica L. in storage life

International Nuclear Information System (INIS)

Soomro, R.K.; Sherazi, S.T.H.

2013-01-01

Mango (Mangifera indica L.) fruit has a relatively short storage life due to perishable nature. In order to increases the storage life of langra mangoes, fruits were coated with sunflower wax. Mangoes were stored at room and refrigerated temperature. Sunflower wax coating protects the mangoes in greater proportion to change their color, weight loss, moisture loss, pH and total soluble solids content. The sensorial panel also favors the grander role of sunflower wax coating. Application of sunflower wax coatings had no effect on vitamin C content of mangoes variety and could increases mango storage time around 30 days under regular storage conditions. Sunflower wax coating also inhibited the growth of micro-organisms. The data reveal that by applying a sunflower wax coating effectively prolongs the quality which attributes and extends the shelf life of mango. (author)

GC-MS Metabolomics to Evaluate the Composition of Plant Cuticular Waxes for Four Triticum aestivum Cultivars

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Florent D. Lavergne

2018-01-01

Full Text Available Wheat (Triticum aestivum L. is an important food crop, and biotic and abiotic stresses significantly impact grain yield. Wheat leaf and stem surface waxes are associated with traits of biological importance, including stress resistance. Past studies have characterized the composition of wheat cuticular waxes, however protocols can be relatively low-throughput and narrow in the range of metabolites detected. Here, gas chromatography-mass spectrometry (GC-MS metabolomics methods were utilized to provide a comprehensive characterization of the chemical composition of cuticular waxes in wheat leaves and stems. Further, waxes from four wheat cultivars were assayed to evaluate the potential for GC-MS metabolomics to describe wax composition attributed to differences in wheat genotype. A total of 263 putative compounds were detected and included 58 wax compounds that can be classified (e.g., alkanes and fatty acids. Many of the detected wax metabolites have known associations to important biological functions. Principal component analysis and ANOVA were used to evaluate metabolite distribution, which was attributed to both tissue type (leaf, stem and cultivar differences. Leaves contained more primary alcohols than stems such as 6-methylheptacosan-1-ol and octacosan-1-ol. The metabolite data were validated using scanning electron microscopy of epicuticular wax crystals which detected wax tubules and platelets. Conan was the only cultivar to display alcohol-associated platelet-shaped crystals on its abaxial leaf surface. Taken together, application of GC-MS metabolomics enabled the characterization of cuticular wax content in wheat tissues and provided relative quantitative comparisons among sample types, thus contributing to the understanding of wax composition associated with important phenotypic traits in a major crop.

Waxes and plastic film in relation to the shelf life of yellow passion fruit

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Mota Wagner Ferreira da

2003-01-01

Full Text Available The high perishability of the yellow passion fruit (Passiflora edulis f. flavicarpa reduces its postharvest conservation and availability, mainly for in natura consumption. These losses of quality and commercial value occur due to the high respiration and loss of water. This work aimed to evaluate the influence of a modified atmosphere - wax emulsions and plastic film - on the shelf life of the yellow passion fruit. Plastic film (Cryovac D-955, 15 mum thickness reduced fresh weight loss and fruit wilting, kept higher fruit and rind weight and higher pulp osmotic potential over the storage period. However, it was not efficient in the control of rottenness. Sparcitrus wax (22-23% polyethylene/maleyc resin caused injury to the fruit, high fruit weight losses and wilting and resulted in lower pulp osmotic potential; this wax lead to a higher concentration of acid and a lower relation of soluble solids/acidity. Among the tested waxes, Fruit Wax (18-21% carnauba wax was the best, promoting reduced weight loss, wilting and rottenness.

Anatomically realistic ultrasound phantoms using gel wax with 3D printed moulds

Science.gov (United States)

Maneas, Efthymios; Xia, Wenfeng; Nikitichev, Daniil I.; Daher, Batol; Manimaran, Maniragav; Wong, Rui Yen J.; Chang, Chia-Wei; Rahmani, Benyamin; Capelli, Claudio; Schievano, Silvia; Burriesci, Gaetano; Ourselin, Sebastien; David, Anna L.; Finlay, Malcolm C.; West, Simeon J.; Vercauteren, Tom; Desjardins, Adrien E.

2018-01-01

Here we describe methods for creating tissue-mimicking ultrasound phantoms based on patient anatomy using a soft material called gel wax. To recreate acoustically realistic tissue properties, two additives to gel wax were considered: paraffin wax to increase acoustic attenuation, and solid glass spheres to increase backscattering. The frequency dependence of ultrasound attenuation was well described with a power law over the measured range of 3-10 MHz. With the addition of paraffin wax in concentrations of 0 to 8 w/w%, attenuation varied from 0.72 to 2.91 dB cm-1 at 3 MHz and from 6.84 to 26.63 dB cm-1 at 10 MHz. With solid glass sphere concentrations in the range of 0.025-0.9 w/w%, acoustic backscattering consistent with a wide range of ultrasonic appearances was achieved. Native gel wax maintained its integrity during compressive deformations up to 60%; its Young’s modulus was 17.4  ±  1.4 kPa. The gel wax with additives was shaped by melting and pouring it into 3D printed moulds. Three different phantoms were constructed: a nerve and vessel phantom for peripheral nerve blocks, a heart atrium phantom, and a placental phantom for minimally-invasive fetal interventions. In the first, nerves and vessels were represented as hyperechoic and hypoechoic tubular structures, respectively, in a homogeneous background. The second phantom comprised atria derived from an MRI scan of a patient with an intervening septum and adjoining vena cavae. The third comprised the chorionic surface of a placenta with superficial fetal vessels derived from an image of a post-partum human placenta. Gel wax is a material with widely tuneable ultrasound properties and mechanical characteristics that are well suited for creating patient-specific ultrasound phantoms in several clinical disciplines.

A comparative evaluation of the marginal adaptation of a thermoplastic resin, a light cured wax and an inlay casting wax on stone dies: An in vitro study.

Science.gov (United States)

Gopalan, Reji P; Nair, Vivek V; Harshakumar, K; Ravichandran, R; Lylajam, S; Viswambaran, Prasanth

2018-01-01

Different pattern materials do not produce copings with satisfactory, marginal accuracy when used on stone dies at varying time intervals. The purpose of this study was to evaluate and compare the vertical marginal accuracy of patterns formed from three materials, namely, thermoplastic resin, light cured wax and inlay casting wax at three-time intervals of 1, 12, and 24 h. A master die (zirconia abutment mimicking a prepared permanent maxillary central incisor) and metal sleeve (direct metal laser sintering crown #11) were fabricated. A total of 30 stone dies were obtained from the master die. Ten patterns were made each from the three materials and stored off the die at room temperature. The vertical marginal gaps were measured using digital microscope at 1, 12, and 24 h after reseating with gentle finger pressure. The results revealed a significant statistical difference in the marginal adaptation of three materials at all the three-time intervals. Light cured wax was found to be most accurate at all time intervals, followed by thermoplastic resin and inlay casting wax. Furthermore, there was a significant difference between all pairs of materials. The change in vertical marginal gap from 1 to 24 h between thermoplastic resin and light cured wax was not statistically significant. The marginal adaptation of all the three materials used, was well within the acceptable range of 25-70 μm. The resin pattern materials studied revealed significantly less dimensional change than inlay casting wax on storage at 1, 12, and 24 h time intervals. They may be employed in situations where high precision and delayed investing is expected.

Three-dimensional wax patterning of paper fluidic devices.

Science.gov (United States)

Renault, Christophe; Koehne, Jessica; Ricco, Antonio J; Crooks, Richard M

2014-06-17

In this paper we describe a method for three-dimensional wax patterning of microfluidic paper-based analytical devices (μPADs). The method is rooted in the fundamental details of wax transport in paper and provides a simple way to fabricate complex channel architectures such as hemichannels and fully enclosed channels. We show that three-dimensional μPADs can be fabricated with half as much paper by using hemichannels rather than ordinary open channels. We also provide evidence that fully enclosed channels are efficiently isolated from the exterior environment, decreasing contamination risks, simplifying the handling of the device, and slowing evaporation of solvents.

Influence of sleep disturbance, fatigue, vitality on oral health and academic performance in indian dental students.

Science.gov (United States)

Asawa, Kailash; Sen, Nandini; Bhat, Nagesh; Tak, Mridula; Sultane, Pratibha; Mandal, Aritra

2017-01-01

Oral health and academic performance are important contributing factors for a student's professional life. Countless factors affect both, among which sleep, vitality and fatigue are less explored areas that also have a strong impact. The objective of the study was to assess the association of sleep disturbances, fatigue and vitality with self reported oral health status, oral hygiene habits and academic performance of dental students of Udaipur. A descriptive cross-sectional study was conducted among undergraduate and postgraduate dental students of Udaipur. Self-administered structured questionnaire was used to assess the psychological factors, vitality, sleep quality, fatigue, self reported oral health status, habits and academic performance. Analysis of variance and stepwise multiple linear regression were utilized for statistical analysis with 95% confidence level and 5% level of significance. Of the 230 participants, 180 (78.3%) were undergraduates and 50 (21.7%) were postgraduates. Among them, females showed higher scores in disturbed sleep index (2.69±2.14) as compared to males (2.45±1.91). Respondents who had "Poor" dental health, scored more in disturbed sleep index (3.15±1.64) and fatigue scale (20.00±4.88). Subjects who flossed "everyday", were found to have good sleep and more energy (p=0.01) and those who assessed themselves as excellent students scored more in the Vitality Scale (p=0.01) and less in the Sleep index (p=0.01). The present study confirms that disturbed sleep, aliveness and fatigue, all are interlinked with each other and are imperative factors having the potential to alter the oral health status, habits and academics of dental students.

Applications of micro-SAXS/WAXS to study polymer fibers

International Nuclear Information System (INIS)

Riekel, C.

2003-01-01

Instrumentation and selected applications for X-ray microdiffraction experiments on polymer and biopolymer fibers at the European Synchrotron Radiation Facility (ESRF) microfocus beamline are reviewed. Combined SAXS/WAXS experiments can be performed on single fibers with a beam size down to about 5 μm. WAXS experiments can be performed down to about 2 μm and in exceptional cases down to 0.1 μm beam size. The instrumental possibilities are demonstrated for the production line of spider silk

Applications of micro-SAXS/WAXS to study polymer fibers

Energy Technology Data Exchange (ETDEWEB)

Riekel, C. E-mail: riekel@esrf.fr

2003-01-01

Instrumentation and selected applications for X-ray microdiffraction experiments on polymer and biopolymer fibers at the European Synchrotron Radiation Facility (ESRF) microfocus beamline are reviewed. Combined SAXS/WAXS experiments can be performed on single fibers with a beam size down to about 5 {mu}m. WAXS experiments can be performed down to about 2 {mu}m and in exceptional cases down to 0.1 {mu}m beam size. The instrumental possibilities are demonstrated for the production line of spider silk.

Applications of micro-SAXS/WAXS to study polymer fibers

Science.gov (United States)

Riekel, C.

2003-01-01

Instrumentation and selected applications for X-ray microdiffraction experiments on polymer and biopolymer fibers at the European Synchrotron Radiation Facility (ESRF) microfocus beamline are reviewed. Combined SAXS/WAXS experiments can be performed on single fibers with a beam size down to about 5 μm. WAXS experiments can be performed down to about 2 μm and in exceptional cases down to 0.1 μm beam size. The instrumental possibilities are demonstrated for the production line of spider silk.

Cuticular waxes in alpine meadow plants: climate effect inferred from latitude gradient in Qinghai-Tibetan Plateau.

Science.gov (United States)

Guo, Yanjun; Guo, Na; He, Yuji; Gao, Jianhua

2015-09-01

Alpine meadow ecosystems are susceptible to climate changes. Still, climate impact on cuticular wax in alpine meadow plants is poorly understood. Assessing the variations of cuticular wax in alpine meadow plants across different latitudes might be useful for predicting how they may respond to climate change. We studied nine alpine meadows in a climate gradient in the east side of Qinghai-Tibetan Plateau, with mean annual temperature ranging from -7.7 to 3.2°C. In total, 42 plant species were analyzed for cuticular wax, averaged 16 plant species in each meadow. Only four plant species could be observed in all sampling meadows, including Kobresia humilis,Potentilla nivea,Anaphalis lacteal, and Leontopodium nanum. The amounts of wax compositions and total cuticular wax in the four plant species varied among sampling meadows, but no significant correlation could be observed between them and temperature, precipitation, and aridity index based on plant species level. To analyze the variations of cuticular wax on community level, we averaged the amounts of n-alkanes, aliphatic acids, primary alcohols, and total cuticular wax across all investigated plant species in each sampling site. The mean annual temperature, mean temperature in July, and aridity index were significantly correlated with the averaged amounts of wax compositions and total cuticular wax. The average chain length of n-alkanes in both plant and soil linearly increased with increased temperature, whereas reduced with increased aridity index. No significant correlation could be observed between mean annual precipitation and mean precipitation from June to August and the cuticular wax amounts and average chain length. Our results suggest that the survival of some alpine plants in specific environments might be depended on their abilities in adjusting wax deposition on plant leaves, and the alpine meadow plants as a whole respond to climate change, benefiting the stability of alpine meadow ecosystem.

Surface and elemental alterations of dental alloys induced by electro discharge machining (EDM).

Science.gov (United States)

Zinelis, Spiros

2007-05-01

To evaluate the surface and elemental alterations induced by electro discharge machining (EDM) on the surface of dental cast alloys used for the fabrication of implant retained meso- and super-structures. A completed cast model of an arch that received dental implants was used for the preparation of six wax patterns which were divided into three groups (Au, Co and Ti). The wax patterns of the Au and Co groups were invested with conventional phosphate-bonded silica-based investment material and the Ti group with magnesia-based investment material. The investment rings of the Au and Co groups were cast with an Au-Ag alloy (Stabilor G) and a Co-Cr base alloy (Okta C), respectively, while the investment rings of group Ti were cast with cp Ti (Biotan). One casting of each group was subjected to electro discharge machining (EDM); the other was conventionally ground and polished. The surface morphology and the elemental compositions of conventionally and EDM-finished surfaces were studied by SEM/X-ray EDS analysis. Six spectra were collected from each surface employing the area scan mode and the mean value of each element between conventionally and EDM-finished surfaces was statistically analyzed by t-test (a=0.05). Then the specimens of each group were cut perpendicular to their longitudinal axis and after metallographic grinding and polishing the cross-sections studied under the SEM. The EDM surfaces showed a significant increase in C due to the decomposition of the dielectric fluid during spark erosion. Moreover, a significant Cu uptake was noted on these surfaces from the decomposition of the Cu electrodes used for EDM. Cross-sectional analysis showed that all alloys developed a superficial zone (recast layer) varying from 2 microm for Au-Ag to 10 microm for Co-Cr alloy. The elemental composition of dental alloy surfaces is significantly altered after EDM treatment.

Composition of the epicuticular and intracuticular wax layers on Kalanchoe daigremontiana (Hamet et Perr. de la Bathie) leaves.

Science.gov (United States)

van Maarseveen, Clare; Jetter, Reinhard

2009-05-01

Epicuticular and intracuticular waxes from both adaxial and abaxial surfaces of the leaves of Kalanchoe daigremontiana were analyzed. All wax mixtures were found to contain approximately equal amounts of triterpenoids and very long chain fatty acid (VLCFA) derivatives. The triterpenoid fraction consisted of glutinol (8-19% of the total wax) and friedelin (4-9%), together with smaller amounts of glutanol, glutinol acetate, epifriedelanol, germanicol and beta-amyrin. The VLCFA derivatives comprised C27-C35 alkanes (19-37% of the total wax), C32-C34 aldehydes (3-7%), C32 and C34 fatty acids (0.2-3%), C26-C36 primary alcohols (4-8%), and C42-C52 alkyl esters (2-9%). The wax layers were found to differ in triterpenoid amounts, with the intracuticular wax containing higher percentages of most triterpenoids than the epicuticular wax. Friedelin, the only triterpenoid ketone present, showed the opposite distribution with higher proportions in the epicuticular wax. VLCFA derivatives also accumulated to higher percentages in the epicuticular than in the intracuticular wax layer. Epicuticular wax crystals were observed on both the adaxial and abaxial leaf surfaces.

The deformation of wax patterns and castings in investment casting technology

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A. Herman

2012-01-01

Full Text Available The dimensional accuracy of the final casting of Inconel alloy 738 LC is affected by many aspects. One of them is the choice of method and time of cooling wax model for precision investment casting. The main objective was to study the initial deformation of the complex shape of the casting of the rotor blades. Various approaches have been tested for cooling wax pattern. When wax models are cooling on the air, without clamping in jig for cooling, deviations from the ideal shape of the casting are very noticeable (up to 8 mm and most are in extreme positions of the model. When blade is cooled in fixing jig in water environment, the resulting deviations compared with cooling in air are significantly larger, sometimes up to 10 mm. This itself does not mean that the final shape of the casting is dimensionally more accurate with usage of wax models, which have deviations from the ideal position smaller. Another deformation occurs when shell mould is produced around wax pattern and furthermore deformations emerge while casting of blade is cooling. This paper demonstrates first steps in describing complex process of deformations of Inconel alloy blades produced with investment casting technology by comparing results from thermal imagery, simulations in foundry simulation software ProCAST 2010 and measurements from CNC scanning system Carl Zeiss MC 850. Conclusions are so far not groundbreaking, but it seems deformations of wax pattern and deformations of castings do in some cases cancel each other by having opposite directions. Describing entirely whole process of deformations will help increase precision of blade castings so that models at the beginning and blades in the end are the same.

CARNAUBA WAX USED AS AN HYDROPHOBIC AGENT FOR EXPANDED VERMICULITE

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M.A.F. Melo

1998-03-01

Full Text Available This work deals with the use of carnauba wax as an expansion and hydrophobicity agent for vermiculite, to be utilized in the sorption process of oil in water. Evaluation of the system (oil-water-hydrophobic vermiculite submersion percentage was considered in assessing the performance of vermiculite in comparison to a Mexican turf. Carnauba wax seems to be more efficient in both fresh and salt waters.

Effects of Wax Coating on the Moisture Loss of Cucumbers at Different Storage Temperatures

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Jian Li

2018-01-01

Full Text Available The effects of wax coating on moisture loss of cucumbers (Cucumis sativus L., cv. Jinglv were investigated at different temperatures. Cucumbers were treated with 10% (volume : volume wax and then stored at 15, 20, 25, or 30°C and 55% relative humidity. The changes in the mass of samples were recorded every 6 h. Results showed that wax coating along with low temperature was very effective in preventing moisture loss of cucumbers during simulated distribution. After 48 h storage, moisture loss in wax treated cucumbers at 15°C was 45% lower than the control at 30°C. Furthermore, a kinetic model was developed to study the influence of temperature on moisture loss based on the Arrhenius law. The model successfully described changes in cucumber moisture loss at different temperatures during storage. The shelf life of cucumber was also predicted using the kinetic model. A synergistic effect was found between wax coating and storage temperature on cucumber shelf life. Wax coating combined with low storage temperature was an effective method to extend the shelf life of cucumber fruit.

Co-metabolism of DDT by the newly isolated bacterium, Pseudoxanthomonas sp. wax

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Guangli Wang

2010-06-01

Full Text Available Microbial degradation of 1,1,1-trichloro-2,2-bis(p-chlorophenylethane (DDT is the most promising way to clean up DDT residues found in the environment. In this paper, a bacterium designated as wax, which was capable of co-metabolizing DDT with other carbon sources, was isolated from a long-term DDT-contaminated soil sample by an enrichment culture technique. The new isolate was identified as a member of the Pseudoxanthomonas sp., based on its morphological, physiological and biochemical properties, as well as by 16S rRNA gene analysis. In the presence of 100 mg l-1 glucose, the wax strain could degrade over 95% of the total DDT, at a concentration of 20 mg l-1, in 72 hours, and could degrade over 60% of the total DDT, at a concentration of 100 mg l-1, in 144 hours. The wax strain had the highest degradation efficiency among all of the documented DDT-degrading bacteria. The wax strain could efficiently degrade DDT at temperatures ranging from 20 to 37ºC, and with initial pH values ranging from 7 to 9. The bacterium could also simultaneously co-metabolize 1,1-dichloro-2,2-bis(p-chlorophenylethane (DDD, 2,2-bis(p-chlorophenyl-1,1-dichlorethylene (DDE, and other organochlorine compounds. The wax strain could also completely remove 20 mg kg-1 of DDT from both sterile and non-sterile soils in 20 days. This study demonstrates the significant potential use of Pseudoxanthomonas sp. wax for the bioremediation of DDT in the environment.

Numerical performance study of paraffin wax dispersed with alumina in a concentric pipe latent heat storage system

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Valan Arasu Amirtham

2013-01-01

Full Text Available Latent heat energy storage systems using paraffin wax could have lower heat transfer rates during melting/freezing processes due to its inherent low thermal conductivity. The thermal conductivity of paraffin wax can be enhanced by employing high conductivity materials such as alumina (Al2O3. A numerical analysis has been carried out to study the performance enhancement of paraffin wax with nanoalumina (Al2O3 particles in comparison with simple paraffin wax in a concentric double pipe heat exchanger. Numerical analysis indicates that the charge-discharge rates of thermal energy can be greatly enhanced using paraffin wax with alumina as compared with a simple paraffin wax as PCM.

Epicuticular waxes from caatinga and cerrado species and their efficiency against water loss

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Oliveira Antonio F. M.

2003-01-01

Full Text Available The effects of the contents and chemical composition of the foliar epicuticular waxes of species from the caatinga (Aspidosperma pyrifolium, Capparis yco, Maytenus rigida and Ziziphus joazeiro and cerrado (Aristolochia esperanzae, Didymopanax vinosum, Strychnos pseudoquina and Tocoyena formosa were evaluated as to the resistance to water loss by means of an experimental device constructed for this purpose. In general, the waxes of the caatinga species investigated were more efficient against water loss than cerrado species. Increase of the thickness of the waxy deposits from 40 to 90m g.cm-2 had no significant effect on the resistance to water loss. The chemistry of the wax constituents was shown to be an important factor to determine the degree of resistance to evaporation. n-Alkanes and alcoholic triterpenes were the most efficient barriers, while hentriacontan-16-one (a ketone and ursolic acid (an acid triterpene revealed lowefficiency. The higher efficiency of the waxes of the leaves from caatinga species (mainly those of C. yco and Z. joazeiro is probably accounted for the predominance of n-alkanes in their composition. The lower efficiency of the waxes of A. pyrifolium (caatinga, T. formosa and A. esperanzae (both species from the cerrado is probably a consequence of the predominance of triterpenoids in the waxes of the two former species and hentriacontan-16-one in the latter.

Wax inhibitor based on ethylene vinyl acetate with methyl methacrylate and diethanolamine for crude oil pipeline

Science.gov (United States)

Anisuzzaman, S. M.; Abang, S.; Bono, A.; Krishnaiah, D.; Karali, R.; Safuan, M. K.

2017-06-01

Wax precipitation and deposition is one of the most significant flow assurance challenges in the production system of the crude oil. Wax inhibitors are developed as a preventive strategy to avoid an absolute wax deposition. Wax inhibitors are polymers which can be known as pour point depressants as they impede the wax crystals formation, growth, and deposition. In this study three formulations of wax inhibitors were prepared, ethylene vinyl acetate, ethylene vinyl acetate co-methyl methacrylate (EVA co-MMA) and ethylene vinyl acetate co-diethanolamine (EVA co-DEA) and the comparison of their efficiencies in terms of cloud point¸ pour point, performance inhibition efficiency (%PIE) and viscosity were evaluated. The cloud point and pour point for both EVA and EVA co-MMA were similar, 15°C and 10-5°C, respectively. Whereas, the cloud point and pour point for EVA co-DEA were better, 10°C and 10-5°C respectively. In conclusion, EVA co-DEA had shown the best % PIE (28.42%) which indicates highest percentage reduction of wax deposit as compared to the other two inhibitors.

Role of needle surface waxes in dynamic exchange of mono- and sesquiterpenes

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J. Joensuu

2016-06-01

Full Text Available Biogenic volatile organic compounds (BVOCs produced by plants have a major role in atmospheric chemistry. The different physicochemical properties of BVOCs affect their transport within and out of the plant as well as their reactions along the way. Some of these compounds may accumulate in or on the waxy surface layer of conifer needles and participate in chemical reactions on or near the foliage surface. The aim of this work was to determine whether terpenes, a key category of BVOCs produced by trees, can be found on the epicuticles of Scots pine (Pinus sylvestris L. and, if so, how they compare with the terpenes found in shoot emissions of the same tree. We measured shoot-level emissions of pine seedlings at a remote outdoor location in central Finland and subsequently analysed the needle surface waxes for the same compounds. Both emissions and wax extracts were clearly dominated by monoterpenes, but the proportion of sesquiterpenes was higher in the wax extracts. There were also differences in the terpene spectra of the emissions and the wax extracts. The results, therefore, support the existence of BVOC associated to the epicuticular waxes. We briefly discuss the different pathways for terpenes to reach the needle surfaces and the implications for air chemistry.

Characterization and chemical composition of epicuticular wax from banana leaves grown in Northern Thailand

OpenAIRE

Suporn Charumanee; Songwut Yotsawimonwat; Panee Sirisa-ard; Kiatisak Pholsongkram

2017-01-01

This study aimed to investigate the physicochemical properties and chemical composition of epicuticular wax extracted from leaves of Kluai Namwa, a banana cultivar which is widely grown in Northern Thailand. Its genotype was identified by a botanist. The wax was extracted using solvent extraction. The fatty acid profiles and physicochemical properties of the wax namely melting point, congealing point, crystal structures and polymorphism, hardness, color, and solubility were examin...

Procedures for extraction and purification of leaf wax biomarkers from peats

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J.E. Nichols

2011-12-01

Full Text Available Palaeoecological and palaeoclimate reconstruction, using leaf wax biomarkers, is a relatively new sub-discipline of peatland science. The ability to process large numbers of samples rapidly for biomarkers makes this type of analysis particularly appealing. This review is a guide to the preparation of leaf waxes for analysis by gas chromatography. The main phases of preparation are extraction of soluble organic compounds from sediment, separation of the total extract into fractions of differing polarity, and the derivatisation of polar functional groups. The procedures described here are not meant be exhaustive of all organic geochemical possibilities in peatlands, but a distillation of methods for the preparation of leaf waxes that are commonly and increasingly being used in palaeoecological and palaeoclimatological studies.

Radiotherapic Valuation of Paraffin Wax for Patients with Oral Cancer

Energy Technology Data Exchange (ETDEWEB)

Na, Kyung Su; Seo, Seuk Jin; Lee, Je Hee; Yoo, Sook Heun [Dept. of Radiation Oncology, Seoul National University Hosdital, Seoul (Korea, Republic of)

2011-03-15

This study is designed to investigate radiotherapic valuation of Paraffin Wax, which is newly formed for this study and generally utilized in dentistry, and Mouth Piece and Putty impression, which are commonly used in radiotherapy, for oral cavity as a compensator. Each compensator was formed by 10 x 10 x 1 cm and measured radiation dose attenuation ratio with reference of water phantom which is made of tissue-equivalent materials. Two patients with oral cancer underwent DRR (Digitally Reconstructed Radiogrph) of Offline Review Program of Aria System and Portal vision for 5 times for each material to evaluate reproducibility by each filling materials. Moreover, MU (monitor unit) changes by dose absorption were considered in the case of inevitable implication of an filling materials in the range for radiotherapy. Radiation dose attenuation ratios were shown -0.7{approx}+3.7% for Mouth Piece, +0.21{approx}+0.39% for Paraffin Wax and -2.71{approx}-1.76% for Putty impression. Error ranges of reproducibility of positions were measured {+-}3 mm for Mouth Piece, {+-}2 mm for Paraffin Wax and {+-}2 mm for Putty impression. Difference of prescription MU from dose absorption with an filling material increased +7.8% (250 MU) in Putty impression and -0.9% (230 MU) in Paraffin Wax as converted into a percentage from the standard phantom, Water 232 MU. Dose reduction of boundary between cavity and tissue was observed for Mouth Piece. Mouth Piece also had low reproducibility of positions as it had no reflection of anatomy of oral cavity even though it was a proper material to separate Maxilla and Mandible during therapy. On the other hand, Putty impression was a suitable material to correctly re-position oral cavity as before. However, it risked normal tissues getting unnecessary over irradiation and it caused radiation dose decrease by -2.5% for 1cm volume in comparison of it of water phantom. Dose reduction in Paraffin Wax, Fat Tissue-Equivalent Material, was smaller than other

[Comparative adaptation of crowns of selective laser melting and wax-lost-casting method].

Science.gov (United States)

Li, Guo-qiang; Shen, Qing-yi; Gao, Jian-hua; Wu, Xue-ying; Chen, Li; Dai, Wen-an

2012-07-01

To investigate the marginal adaptation of crowns fabricated by selective laser melting (SLM) and wax-lost-casting method, so as to provide an experimental basis for clinic. Co-Cr alloy full crown were fabricated by SLM and wax-lost-casting for 24 samples in each group. All crowns were cemented with zinc phosphate cement and cut along longitudinal axis by line cutting machine. The gap between crown tissue surface and die was measured by 6-point measuring method with scanning electron microscope (SEM). The marginal adaptation of crowns fabricated by SLM and wax-lost-casting were compared statistically. The gap between SLM crowns were (36.51 ± 2.94), (49.36 ± 3.31), (56.48 ± 3.35), (42.20 ± 3.60) µm, and wax-lost-casting crowns were (68.86 ± 5.41), (58.86 ± 6.10), (70.62 ± 5.79), (69.90 ± 6.00) µm. There were significant difference between two groups (P casting method and SLM method provide acceptable marginal adaptation in clinic, and the marginal adaptation of SLM is better than that of wax-lost-casting method.

Effect of soil moisture management on the quality of wax apple | Lin ...

African Journals Online (AJOL)

Wax apple (Syzygium samarngense Merr.et Perry) was one of the economically planted fruits in Taiwan. This research was conducted to evaluate the effects of different soil moisture management on increasing wax apple quality. It was preceded at two different soil properties (shallow soil and alluvial soil) in Pingtung, ...

ETHNOECOLOGY AND ETHNOBOTANY OF THE PALM CARNAUBA WAX IN BRAZILIAN SEMI-ARID

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Rodrigo Ferreira de Sousa

2015-12-01

Full Text Available The aim of this study was to investigate aspects of ethnoecological and ethnobotanical of carnauba wax (Copernicia prunifera (Miller H. E. Moore, Arecaceae in an extractive community of municipality of Ipanguaçu, Rio Grande do Norte state. We interviewed key informants, using the technique of inducing nonspecific, guided tour and direct observation to confirm the data. According to most residents of Pedro Ezequiel Araújo community, the area of carnauba wax in the region is natural. In the research ethnoecological, 73% of informants reported the occurrence of “a different kind of carnauba”, known as “white carnauba” phenotypically distinct from the “common carnauba wax” by presenting clear stipe, smaller fruits and absence of spines on the petiole, and is rare at the study site. Much of the informants observed phenological phases of carnauba wax, being consistent in stating that the species has fruits dispersed by bats. In ethnobotany, powder wax was cited by all as the most important product extracted from leaves of carnauba and the most used, followed by fruit, stem and root. Were still reported the division of work in the extraction of powder wax from the carnauba. The results of this research will contribute to knowledge of ethnobotanical and ethnoecological carnauba, supporting strategies for management and conservation of natural populations.

Isolation and recrystallization of epicuticular waxes from Sorbus and Cotoneaster leaves

OpenAIRE

Ganeva Tsveta; Stefanova Miroslava; Koleva Dimitrina; Ruiz Segundo Ríos

2015-01-01

Wax morphology and chemical composition are widely accepted to be important for the protective properties of the leaf’s surface and also valuable characteristics in plant systematics. The leaves of Sorbus domestica L. and Cotoneaster granatensis Boiss., species of two large genera with intricate taxonomy referred to subtribe Pyrinae, Rosaceae (formerly subfamily Maloideae), were studied by scanning electron microscope (SEM) and performing different methods of wax isola...

Investigation of wax precipitation in crude oil: Experimental and modeling

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Taraneh Jafari Behbahani

2015-09-01

Full Text Available In this work, a series of experiments were carried to investigation of rheological behavior of crude oil using waxy crude oil sample in the absence/presence of flow improver such as ethylene-vinyl acetate copolymer. The rheological data covered the temperature range of 5–30 °C. The results indicated that the performance of flow improver was dependent on its molecular weight. Addition of small quantities of flow improver, can improve viscosity and pour point of crude oil. Also, an Artificial Neural Network (ANN model using Multi-Layer Perceptron (MLP topology has been developed to account wax appearance temperature and the amount of precipitated wax and the model was verified using experimental data given in this work and reported in the literature. In order to compare the performance of the proposed model based on Artificial Neural Network, the wax precipitation experimental data at different temperatures were predicted using solid solution model and multi-solid phase model. The results showed that the developed model based on Artificial Neural Network can predict more accurately the wax precipitation experimental data in comparison to the previous models such as solid solution and multi-solid phase model with AADs less than 0.5%. Furthermore, the number of parameters required for the Artificial Neural Network (ANN model is less than the studied thermodynamic models.

Wax solidification of drying agents containing tritiated water

International Nuclear Information System (INIS)

Mishikawa, M.; Kido, H.

1984-01-01

It is necessary to immobilize the tritium not to give any impact on the environmental biosphere because tritium may give profound effects in the metabolic pathway. One of the most probable methods of immobilizing tritium would be incorporation of tritiated water in solid forms. Any drying or dehydration technique would be effective in a tritium cleanup system for off-gas streams containing tritium or tritiated water. Commonly used drying agents such as activated alumina, silica gel, molecular sieves and calcium sulfate are of value for removal of water vapour from air or other gases. For long term tritium storage, however, these adsorptive materials should be enveloped to prevent contact with water or water vapour because the rate of leaching, evaporation or diffusion of tritium from these porous materials is so large. The beeswax solidification method of the packed bed of drying agents adsorbing tritiated water is developed in this study, where the wax solidification procedure is performed by pouring the melt of wax into the void space of the packed bed of the drying agents and successive gradual cooling. The observed values of diffusivity or permeability of tritium in the wax solidified materials are about one-thousandth of those obtained for the cement block. Effect of coating on the rate of leaching is also discussed

Radiological properties of a wax-gypsum compensator material

International Nuclear Information System (INIS)

Plessis, F.C.P. du; Willemse, C.A.

2005-01-01

In this paper the radiological properties of a compensator material consisting of wax and gypsum is presented. Effective attenuation coefficients (EACs) have been determined from transmission measurements with an ion chamber in a Perspex phantom. Measurements were made at 80 and 100 cm source-to-skin distance (SSD) for beam energies of 6, 8, and 15 MV, for field sizes ranging from narrow beam geometries up to 40x40 cm 2 , and at measurement depths of maximum dose build-up, 5 and 10 cm. A parametrization equation could be constructed to predict the EAC values within 4% uncertainty as a function of field size and depth of measurement. The EAC dependence on off-axis position was also quantified at each beam energy and SSD. It was found that the compensator material reduced the required thickness for compensation by 26% at 8 MV when compared to pure paraffin wax for a 10x10 cm 2 field. Relative surface ionization (RSI) measurements have been made to quantify the effect of scattered electrons from the wax-gypsum compensator. Results indicated that for 80 cm SSD the RSI would exceed 50% for fields larger than 15x15 cm 2 . At 100 cm SSD the RSI values were below 50% for all field sizes used

The use of paraffin wax in a new solar cooker with inner and outer reflectors

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Arabacigil Bihter

2015-01-01

Full Text Available In this paper, the potential use and effectiveness of paraffin wax in a new solar cooker was experimentally investigated during daylight and late evening hours. For these experiments, a cooker having an inner reflecting surface was designed, constructed by filling paraffin wax and metal shavings. The side- and sub-surface temperatures of the paraffin wax in the cooker are measured in the summer months of June and July. The thermal efficiency of the cooker was tested on different conditions. The results show that the optimum angle of the outer reflector is 30°. Here, the peak temperature of the paraffin wax in the solar cooker was 83.4 °C. The average solar radiation reflected makes a contribution of 9.26% to the temperature of paraffin wax with the outer reflector. The solar cooker with the outer reflector angle of 30° receives also reflected radiation from the inner reflectors. Besides, the heating time is decreased to approximately 1 hour. The designed solar cooker can be effectively used with 30.3% daily thermal efficiency and paraffin wax due to the amount of energy stored.

Effect of spatial distribution of wax and PEG-isocyanate on the morphology and hydrophobicity of starch films.

Science.gov (United States)

Muscat, Delina; Adhikari, Raju; Tobin, Mark J; McKnight, Stafford; Wakeling, Lara; Adhikari, Benu

2014-10-13

This study proposes a novel method for improving surface hydrophobicity of glycerol plasticized high amylose (HAG) films. We used polyethylene glycol isocyanate (PEG-iso) crosslinker to link HAG and three natural waxes (beeswax, candelilla wax and carnauba wax) to produce HAG+wax+PEG-iso films. The spatial distributions of wax and PEG-iso across the thickness of these films were determined using Synchrotron-based Fourier transform infrared spectroscopy. The hydrophobicity and surface morphology of the films were determined using contact angle (CA) and scanning electron microscopic measurements, respectively. The distribution patterns of wax and the PEG-iso across the thickness of the film, and the nature of crystalline patterns formed on the surface of these films were found to be the key factors affecting surface hydrophobicity. The highest hydrophobicity (CA >90°) was created when the PEG-iso was primarily distributed in the interior of the films and a hierarchical circular pinnacle structure of solidified wax was formed on the surface. Copyright © 2014 Elsevier Ltd. All rights reserved.

Cuticular wax accumulation is associated with drought tolerance in wheat near-isogenic lines

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Jianmin Song

2016-11-01

Full Text Available Previous studies have shown that wheat grain yield is seriously affected by drought stress, and leaf cuticular wax is reportedly associated with drought tolerance. However, most studies have focused on cuticular wax biosynthesis and model species. The effects of cuticular wax on wheat drought tolerance have rarely been studied. The aims of the current study were to study the effects of leaf cuticular wax on wheat grain yield under drought stress using the above-mentioned wheat NILs and to discuss the possible physiological mechanism of cuticular wax on high grain yield under drought stress. Compared to water-irrigated (WI conditions, the cuticular wax content (CWC in glaucous and non-glaucous NILs under drought-stress (DS conditions both increased; mean increase values were 151.1% and 114.4%, respectively, which was corroborated by scanning electronic microscopy images of large wax particles loaded on the surfaces of flag leaves. The average yield of glaucous NILs was higher than that of non-glaucous NILs under DS conditions in 2014 and 2015; mean values were 7368.37 kg·ha-1 and 7103.51 kg·ha-1. This suggested that glaucous NILs were more drought-tolerant than non-glaucous NILs (P = 0.05, which was supported by the findings of drought tolerance indices TOL and SSI in both years, the relatively high water potential and relative water content, and the low ELWL. Furthermore, the photosynthesis rate (Pn of glaucous and non-glaucous wheat NILs under DS conditions decreased by 7.5% and 9.8%, respectively; however, glaucous NILs still had higher mean values of Pn than those of non-glaucous NILs, which perhaps resulted in the higher yield of glaucous NILs. This could be explained by the fact that glaucous NILs had a smaller Fv/Fm reduction, a smaller PI reduction and a greater ABS/RC increase than non-glaucous NILs under DS conditions. This is the first report to show that wheat cuticular wax accumulation is associated with drought tolerance. Moreover

EFFECT OF OIL TEMPERATURE ON THE WAX DEPOSITION OF CRUDE OIL WITH COMPOSITION ANALYSIS

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Qing Quan

Full Text Available Abstract Wax deposition behavior was investigated in a set of one-inch experiment flow loops, using a local crude oil with high wax content. The temperature of the oil phase is chosen as a variable parameter while the temperature of the coolant media is maintained constant. Detailed composition of the deposit is characterized using High Temperature Gas Chromatography. It was found that the magnitude of the diffusion of the heavier waxy components (C35-C50 decreases when the oil temperature decreases, but the magnitude of the diffusion of the lighter waxy components increases. This result means that the diffusion of wax molecules shifts towards lower carbon number, which further proves the concept of molecular diffusion. Meanwhile, a meaningful phenomenon is that the mass of the deposit increases with the oil temperature decrease, which definitely proves the influence of wax solubility on deposition, while the formation of an incipient gel layer reflects the fact that an increase in the mass of the deposit does not mean a larger wax percentage fraction at lower oil temperature.

Competing With Ronald McDonald, Cap'n Crunch and the Pepsi Generation.

Science.gov (United States)

Kamholtz, J. Dennis; Wood, Bill

1982-01-01

A new approach to elementary health education involves the use of a series of health-related games. The games address a variety of issues including nutrition, substance abuse, and dental health education. The story "Floss is the Boss" is used as an example. (JN)

Gum Disease by the Numbers | NIH MedlinePlus the Magazine

Science.gov (United States)

... us Gum Disease by the Numbers Gum (or periodontal) disease is one of the leading threats to dental health. It's typically caused by poor brushing and flossing habits that allow plaque—a sticky film of bacteria—to build up on teeth and harden. In ...

Review of the Factors that Influence the Condition of Wax Deposition in Subsea Pipelines

Directory of Open Access Journals (Sweden)

Koh Junyi

2018-03-01

Full Text Available When crude oil is transported via sub-sea pipeline, the temperature of the pipeline decreases at a deep depth which causes a difference in temperature with the crude oil inside. This causes the crude oil to dissipate its heat to the surrounding until thermal equilibrium is achieved. This is also known as the cloud point where wax begins to precipitate and solidifies at the walls of the pipeline which obstruct the flow of fluid. The main objective of this review is to quantify the factors that influence wax deposition such as temperature difference between the wall of the pipeline and the fluid flowing within, the flow rate of the fluid in the pipeline and residence time of the fluid in the pipeline. It is found the main factor that causes wax deposition in the pipeline is the difference in temperature between the petroleum pipeline and the fluid flowing within. Most Literature deduces that decreasing temperature difference results in lower wax content deposited on the wall of the pipeline. The wax content increases with rising flow rate. As for the residence time, the amount of deposited wax initially increases when residence time increases until it reaches a peak value and gradually decreases. Flow-loop system and cold finger apparatus were used in literature investigations to determine the trends above. Three new models are generated through a regression analysis based on the results from other authors. These new models form a relationship between temperature difference, flow rate, residence time and Reynolds number with wax deposition. These models have high values of R-square and adjusted R-square which demonstrate the reliability of these models.

The effect of the environment on the structure, quantity and composition of spruce needle wax

International Nuclear Information System (INIS)

Guenthardt-Goerg, M.S.

1994-01-01

The tubular structure (10-nonacosanol), as formed in spring on the wax surface of new spruce needles (Picea abies (L.)Karst.), or as regenerated on previous-year needles, becomes gradually fused and flattened in relation to needle exposure, particularly wind and rain. Structural flattening does not necessarily imply changes in wax quantity, composition or lead to changes in needle transpiration or photosynthesis, and was approximately reproduced by bathing excised twigs in water (with pH having little effect). In 4-year-old plants of one clone planted out at a Swiss plateau and alpine sites, changes in wax structure were similar to those found in mature trees. No such changes were found in plants with O 3 , SO 2 , ambient air, charcoal-filtered air, or in plants grown outside the chambers but shielded from rain. Area-related needle wax quantity in mature trees differed between the two sites, but did not differ in young plants under different treatments (fumigation or planted out at the sites). Minor differences in wax composition, however, were found to be related to the ozone dose of the fumigation or the ambient ozone dose at the sites. In each needle wax sample, 68 compounds grouped into 12 constituent classes were quantified. The quantity of the individual substituent classes varied among wax samples from genetically different mature trees at the two sites in a tree-specific way. Variation of these quantities was not larger than among young cloned plants after different treatments. (orig.)

21 CFR 172.886 - Petroleum wax.

Science.gov (United States)

2010-04-01

... availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register... it is very hygroscopic and will react with some metal containers in the presence of air. Phosphoric... high enough to keep the wax melted. (Note: In preheating the sulfoxide-acid mixture, remove the stopper...

Wax co-cracking synergism of high density polyethylene to alternative fuels

Directory of Open Access Journals (Sweden)

Magdy Motawie

2015-09-01

Full Text Available Attempts have been made to understand the thermal degradation of high density polyethylene (HDPE and their combined co-cracking using different ratios of HDPE and petroleum wax under nitrogen atmosphere. We have conducted the experiments using HDPE as the raw material and petroleum wax as co-feed by at 400 and 450 °C reaction temperatures. The product distribution was noted along with reaction time of 0.5–3 h for the degradation. Thermal gravimetric analysis (TGA technique was used to measure the weight change of the feedstock as a function of temperature and time. Differential scanning calorimetry (DSC was used to determine the degradation temperature. Products were characterized using gas chromatography (GC and infrared spectroscopy (FTIR, some other standard physical methods were used to determine the main properties of the liquid products. Results show that the mixed plastic-wax samples could be converted into gases, gasoline, and middle distillate depending upon the composition of feed polymer/wax ratio. It was found that the products mostly consisted of paraffin and olefin compounds, with carbon numbers of C1–C4, C5–C9 and C10–C19 in the case of gases, gasoline and middle distillate respectively.

Real-time monitoring and measurement of wax deposition in pipelines via non-invasive electrical capacitance tomography

Science.gov (United States)

Lock Sow Mei, Irene; Ismail, Idris; Shafquet, Areeba; Abdullah, Bawadi

2016-02-01

Tomographic analysis of the behavior of waxy crude oil in pipelines is important to permit appropriate corrective actions to be taken to remediate the wax deposit layer before pipelines are entirely plugged. In this study, a non-invasive/non-intrusive electrical capacitance tomography (ECT) system has been applied to provide real-time visualization of the formation of paraffin waxes and to measure the amount of wax fraction from the Malay Basin waxy crude oil sample under the static condition. Analogous expressions to estimate the wax fraction of the waxy crude oil across the temperatures range of 30-50 °C was obtained by using Otsu’s and Kuo’s threshold algorithms. Otsu’s method suggested that the wax fraction can be estimated by the correlation coefficient β =0.0459{{T}3}-5.3535{{T}2}+200.36T-2353.7 while Kuo’s method provides a similar correlation with β =0.0741{{T}3}-8.4915{{T}2}+314.96T-3721.2 . These correlations show good agreements with the results which are obtained from the conventional weighting method. This study suggested that Kuo’s threshold algorithm is more promising when integrated into the ECT system compared to Otsu’s algorithm because the former provides higher accuracy wax fraction measurement results below the wax appearance temperature for waxy crude oil. This study is significant because it serves as a preliminary investigation for the application of ECT in the oil and gas industry for online measurement and detection of wax fraction without causing disturbance to the process flow.

Modeling of asphaltene and wax precipitation

Energy Technology Data Exchange (ETDEWEB)

Chung, F.; Sarathi, P.; Jones, R.

1991-01-01

This research project was designed to focus on the development of a predictive technique for organic deposition during gas injection for petroleum EOR. A thermodynamic model has been developed to describe the effects of temperature, pressure, and composition on asphaltene precipitation. The proposed model combines regular solution theory with Flory-Huggins polymer solutions theory to predict maximum volume fractions of asphaltene dissolved in oil. The model requires evaluation of vapor-liquid equilibria, first using an equation of state followed by calculations of asphaltene solubility in the liquid-phase. A state-of-the-art technique for C{sub 7+} fraction characterization was employed in developing this model. The preliminary model developed in this work was able to predict qualitatively the trends of the effects of temperature, pressure, and composition. Since the mechanism of paraffinic wax deposition is different from that of asphaltene deposition, another thermodynamic model based on the solid-liquid solution theory was developed to predict the wax formation. This model is simple and can predict the wax appearance temperature with reasonable accuracy. Accompanying the modeling work, experimental studies were conducted to investigate the solubility of asphaltene in oil land solvents and to examine the effects of oil composition, CO{sub 2}, and solvent on asphaltene precipitation and its properties. This research focused on the solubility reversibility of asphaltene in oil and the precipitation caused by CO{sub 2} injection at simulated reservoir temperature and pressure conditions. These experiments have provided many observations about the properties of asphaltenes for further improvement of the model, but more detailed information about the properties of asphaltenes in solution is needed for the development of more reliable asphaltene characterization techniques. 50 refs., 8 figs., 7 tabs.

Radiotherapic Valuation of Paraffin Wax for Patients with Oral Cancer

International Nuclear Information System (INIS)

Na, Kyung Su; Seo, Seuk Jin; Lee, Je Hee; Yoo, Sook Heun

2011-01-01

This study is designed to investigate radiotherapic valuation of Paraffin Wax, which is newly formed for this study and generally utilized in dentistry, and Mouth Piece and Putty impression, which are commonly used in radiotherapy, for oral cavity as a compensator. Each compensator was formed by 10 x 10 x 1 cm and measured radiation dose attenuation ratio with reference of water phantom which is made of tissue-equivalent materials. Two patients with oral cancer underwent DRR (Digitally Reconstructed Radiogrph) of Offline Review Program of Aria System and Portal vision for 5 times for each material to evaluate reproducibility by each filling materials. Moreover, MU (monitor unit) changes by dose absorption were considered in the case of inevitable implication of an filling materials in the range for radiotherapy. Radiation dose attenuation ratios were shown -0.7∼+3.7% for Mouth Piece, +0.21∼+0.39% for Paraffin Wax and -2.71∼-1.76% for Putty impression. Error ranges of reproducibility of positions were measured ±3 mm for Mouth Piece, ±2 mm for Paraffin Wax and ±2 mm for Putty impression. Difference of prescription MU from dose absorption with an filling material increased +7.8% (250 MU) in Putty impression and -0.9% (230 MU) in Paraffin Wax as converted into a percentage from the standard phantom, Water 232 MU. Dose reduction of boundary between cavity and tissue was observed for Mouth Piece. Mouth Piece also had low reproducibility of positions as it had no reflection of anatomy of oral cavity even though it was a proper material to separate Maxilla and Mandible during therapy. On the other hand, Putty impression was a suitable material to correctly re-position oral cavity as before. However, it risked normal tissues getting unnecessary over irradiation and it caused radiation dose decrease by -2.5% for 1cm volume in comparison of it of water phantom. Dose reduction in Paraffin Wax, Fat Tissue-Equivalent Material, was smaller than other impressions and

Combined hydrogen and carbon isotopes of plant waxes as an indicator of drought impacts on ancient Maya agriculture

Science.gov (United States)

Douglas, P. M.; Pagani, M.; Eglinton, T. I.; Brenner, M.; Hodell, D. A.; Curtis, J. H.

2012-12-01

There is increasing evidence suggesting that a series of droughts in the Yucatan Peninsula coincided with the Terminal Classic decline of the Classic Maya civilization (ca. 1250 to 1000 years BP). However, there is little evidence directly linking climatic change and changes in human activities in this region. In this study we combine plant-wax δD, δ13C, and Δ14C analyses in two lake sediment cores from southeastern Mexico and northern Guatemala to develop coupled records of hydroclimate variability and human-driven vegetation change. Plant-wax specific Δ14C ages indicate a large input of pre-aged plant waxes into lake sediment. Comparison of plant-wax δD records with other regional hydroclimate proxy records suggest that plant-wax ages are evenly distributed around plant-wax radiocarbon ages, and that applying an age model based on plant-wax radiocarbon ages is appropriate for these lake sediments. We evaluate how differences in plant-wax age distributions influence stable isotope records to assess the age uncertainty associated with records of climate and vegetation change derived from plant-wax stable isotopes. In this low-elevation tropical environment plant-wax δ13C is largely controlled by the relative abundance of C3 and C4 plants. The ancient Maya practiced widespread maize (C4) agriculture and strongly influenced regional C3-C4 vegetation dynamics. Under natural conditions C4 plant coverage and plant-wax δ13C would tend to co-vary positively since C4 plants are well adapted for dry conditions. Under ancient Maya land-use, however, this relationship is likely to be decoupled, since drought would have disrupted C4 agriculture. Combined analysis of plant-wax δD and δ13C from both lakes indicates increasingly divergent trends following ca. 3500 years BP, around the onset of widespread ancient Maya agriculture. After this time high plant-wax δD values tend to correspond with low plant-wax δ13C values and vice versa. This pattern is consistent with

An Evaluation of the Gap Sizes of 3-Unit Fixed Dental Prostheses Milled from Sintering Metal Blocks

OpenAIRE

Jung, Jae-Kwan

2017-01-01

This study assessed the clinical acceptability of sintering metal-fabricated 3-unit fixed dental prostheses (FDPs) based on gap sizes. Ten specimens were prepared on research models by milling sintering metal blocks or by the lost-wax technique (LWC group). Gap sizes were assessed at 12 points per abutment (premolar and molar), 24 points per specimen (480 points in a total in 20 specimens). The measured points were categorized as marginal, axial wall, and occlusal for assessment in a silicone...

Cannabis-induced psychosis associated with high potency "wax dabs".

Science.gov (United States)

Pierre, Joseph M; Gandal, Michael; Son, Maya

2016-04-01

With mounting evidence that the risk of cannabis-induced psychosis may be related to both dose and potency of tetrahydrocannbinol (THC), increasing reports of psychosis associated with cannabinoids containing greater amounts of THC are anticipated. We report two cases of emergent psychosis after using a concentrated THC extract known as cannabis "wax," "oil," or "dabs" raising serious concerns about its psychotic liability. Although "dabbing" with cannabis wax is becoming increasingly popular in the US for both recreational and "medicinal" intentions, our cases raise serious concerns about its psychotic liability and highlight the importance of understanding this risk by physicians recommending cannabinoids for purported medicinal purposes. Published by Elsevier B.V.

Development and properties of a wax ester hydrolase in the cotyledons of jojoba seedlings.

Science.gov (United States)

Huang, A H; Moreau, R A; Liu, K D

1978-03-01

The activity of a wax ester hydrolase in the cotyledons of jojoba (Simmondsia chinensis) seedlings increased drastically during germination, parallel to the development of the gluconeogenic process. The enzyme at its peak of development was obtained in association with the wax body membrane, and its properties were studied. It had an optimal activity at alkaline pH (8.5-9). The apparent K(m) value for N-methylindoxylmyristate was 93 muM. It was stable at 40 C for 30 min but was inactivated at higher temperature. Various divalent cations and ethylenediaminetetraacetate had little effect on the activity. p-Chloromercuribenzoate was a strong inhibitor of the enzyme activity, and its effect was reversed by subsequent addition of dithiothreitol. It had a broad substrate specificity with highest activities on monoglycerides, wax esters, and the native substrate (jojoba wax).

76 FR 773 - Petroleum Wax Candles From the People's Republic of China: Continuation of Antidumping Duty Order

Science.gov (United States)

2011-01-06

... DEPARTMENT OF COMMERCE International Trade Administration [A-570-504] Petroleum Wax Candles From... Trade Commission (``ITC'') that revocation of the antidumping duty order on petroleum wax candles from... order on petroleum wax candles from the PRC pursuant to section 751(c)(2) of the Tariff Act of 1930, as...

Development of lamellar structures in natural waxes - an electron diffraction investigation

Science.gov (United States)

Dorset, Douglas L.

1999-06-01

When they are recrystallized from the melt, natural plant or insect waxes tend to form solid phases with a nematic-like structure (i.e. a parallel array of polymethylene chains with little or no aggregation of the molecules into distinct layers). An electron diffraction study of carnauba wax and two types of beeswax has shown that the degree of molecular organization into lamellar structures can be enhanced by annealing in the presence of benzoic acid, which also acts as an epitaxial substrate. Nevertheless, the resultant layer structure in the annealed solid is not the same as that found for paraffin wax fractions refined from petroleum. Probably because of a small but significant fraction of a very long chain ingredient, the lamellar separation is incomplete, incorporating a number of `bridging molecules' that span the nascent lamellar interface.The same phenomenon has been described recently for a low molecular weight polyethylene.

INVESTIGATION THE FITTING ACCURACY OF CAST AND SLM CO-CR DENTAL BRIDGES USING CAD SOFTWARE

Directory of Open Access Journals (Sweden)

Tsanka Dikova

2017-09-01

Full Text Available The aim of the present paper is to investigate the fitting accuracy of Co-Cr dental bridges, manufactured by three technologies, with the newly developed method using CAD software. The four-part dental bridges of Co-Cr alloys were produced by conventional casting of wax models, casting with 3D printed patterns and selective laser melting. The marginal and internal fit of dental bridges was studied out by two methods – silicone replica test and CAD software. As the silicone replica test characterizes with comparatively low accuracy, a new methodology for investigating the fitting accuracy of dental bridges was developed based on the SolidWorks CAD software. The newly developed method allows the study of the marginal and internal adaptation in unlimited directions and high accuracy. Investigation the marginal fit and internal adaptation of Co-Cr four-part dental bridges by the two methods show that the technological process strongly influences the fitting accuracy of dental restorations. The fitting accuracy of the bridges, cast with 3D printed patterns, is the highest, followed by the SLM and conventionally cast bridges. The marginal fit of the three groups of bridges is in the clinically acceptable range. The internal gap values vary in different regions – it is highest on the occlusal surfaces, followed by that in the marginal and axial areas. The higher fitting accuracy of the bridges, manufactured by casting with 3D printed patterns and SLM, compared to the conventionally cast bridges is a good precondition for their successful implementation in the dental offices and laboratories.

Compound-Specific Radiocarbon Dating Reveals the Age Distribution of Plant-Wax Biomarkers Exported to the Bengal Fan

Science.gov (United States)

Galy, V.; French, K. L.; Hein, C. J.; Haghipour, N.; Wacker, L.; Kudrass, H.; Eglinton, T. I.

2017-12-01

The stable isotope composition of leaf-wax compounds preserved in lacustrine and marine sediments has been widely used to reconstruct terrestrial paleo-environments. However, the timescales of plant-wax storage in continental reservoirs before riverine export are not well known, representing a key uncertainty in paleo-environment studies. We couple numerical models with bulk and leaf-wax fatty acid organic 13C and 14C signatures hosted in a high-deposition-rate sediment core from the Bengal shelf canyon in order to estimate storage timescales within the Ganges-Brahmaputra catchment area. The fatty acid 14C record reveals a muted nuclear weapons bomb spike, requiring that the Ganges-Brahmaputra river system exports a mixture of young and old (pre-aged) leaf-wax compounds. According to numerical simulations, 79-83% of the leaf-wax fatty acids in this core are sourced from continental reservoirs that store organic carbon on an average of 1000-1200 calendar years, while the remainder has an average age of 15 years. These results demonstrate that a majority of the leaf-wax compounds produced in the Ganges-Brahmaputra river basin was stored in soils, floodplains, and wetlands prior to its export to the Bengal Fan. We will discuss the implications of these findings for plant-wax based paleoenvironmental records.

Perceived control and intrinsic vs. extrinsic motivation for oral self-care: a full factorial experimental test of theory-based persuasive messages.

Science.gov (United States)

Staunton, Liam; Gellert, Paul; Knittle, Keegan; Sniehotta, Falko F

2015-04-01

Correlational evidence suggests that perceived control (PC) and intrinsic motivation (IM), key constructs in social cognitive and self-determination theories, may interact to reinforce behavior change. This proof-of-principle study examines the independent and synergistic effects of interventions to increase PC and IM upon dental flossing frequency. University students (n = 185) were randomized in a 2 × 2 full factorial design to receive two computer-based interventions: one to either increase or decrease PC and another to increase either IM or extrinsic motivation. These constructs were measured immediately post-intervention; flossing behavior was measured 1 week later. The interventions to increase PC and PC/IM had main and interaction effects on flossing, respectively. The PC/IM interaction effect was mediated by increases in PC and IM. Combining interventions to increase PC and IM seems to be a promising avenue of research, which has implications for both theory and intervention development.

Clustering of comb and propolis waxes based on the distribution of aliphatic constituents

Directory of Open Access Journals (Sweden)

Custodio Angela R.

2003-01-01

Full Text Available Chemical composition data for 41 samples of propolis waxes and 9 samples of comb waxes of Apis mellifera collected mainly in Brazil were treated using Principal Component Analysis (PCA and Hierarchical Cluster Analysis (HCA. For chemometrical analysis, the distribution of hydrocarbons and residues of alcohols and carboxylic acids of monoesters were considered. The clustering obtained revealed chemical affinities and differences not previously grasped by simple eye-inspection of the data. No consistent differences were detected between comb and propolis waxes. These and previous results suggest that hydrocarbons, carboxylic acids, aliphatic alcohols and esters from both comb and propolis waxes are bee-produced compounds and, hence, the differences detected between one and another region are dependent on genetic factors related to the insects rather than the local flora. The samples analyzed were split into two main clusters, one of them comprising exclusively material collected in the State of São Paulo. The results are discussed with respect to the africanization of honeybees that first took place in that State and therefrom irradiated to other parts of Brazil.

Production of wax esters via microbial oil synthesis from food industry waste and by-product streams.

Science.gov (United States)

Papadaki, Aikaterini; Mallouchos, Athanasios; Efthymiou, Maria-Nefeli; Gardeli, Chryssavgi; Kopsahelis, Nikolaos; Aguieiras, Erika C G; Freire, Denise M G; Papanikolaou, Seraphim; Koutinas, Apostolis A

2017-12-01

The production of wax esters using microbial oils was demonstrated in this study. Microbial oils produced from food waste and by-product streams by three oleaginous yeasts were converted into wax esters via enzymatic catalysis. Palm oil was initially used to evaluate the influence of temperature and enzyme activity on wax ester synthesis catalysed by Novozyme 435 and Lipozyme lipases using cetyl, oleyl and behenyl alcohols. The highest conversion yields (up to 79.6%) were achieved using 4U/g of Novozyme 435 at 70°C. Transesterification of microbial oils to behenyl and cetyl esters was achieved at conversion yields up to 87.3% and 69.1%, respectively. Novozyme 435 was efficiently reused for six and three cycles during palm esters and microbial esters synthesis, respectively. The physicochemical properties of microbial oil derived behenyl esters were comparable to natural waxes. Wax esters from microbial oils have potential applications in cosmetics, chemical and food industries. Copyright © 2017 Elsevier Ltd. All rights reserved.

Biodegradation of paraffin wax by crude Aspergillus enzyme preparations for potential use in removing paraffin deposits.

Science.gov (United States)

Zhang, Junhui; Xue, Quanhong; Gao, Hui; Wang, Ping

2015-11-01

Paraffin deposition problems have plagued the oil industry. Whist mechanical and chemical methods are problematic, microbiological method of paraffin removal is considered an alternative. However, studies have mainly investigated the use of bacteria, with little attention to the potential of fungi. The performance of six Aspergillus isolates to degrade paraffin wax was evaluated under laboratory conditions using solid enzyme preparations. The results showed that all the six enzyme preparations efficiently improved the solubility of paraffin wax in n-hexane and degraded n-alkanes in paraffin wax. The degradation process was accompanied by dynamic production of gases (CO2 and H2 ) and organic acids (oxalate and propionate). The shape of wax crystals markedly changed after enzymatic degradation, with a rough surface and a loose structure. This study indicates that extracellular enzymes from Aspergillus spp. can efficiently degrade paraffin wax. These enzyme preparations have the potential for use in oil wells with paraffin deposition problems. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Retained bone wax on CT at one year after dacryocystorhinostomy: A case report

International Nuclear Information System (INIS)

Kim, Seung Hyun; Park, Dong Woo; Jeong, Jin Yeok; Lee, Jong Ah; Lee, Young Jun

2015-01-01

A 71-year-old man with chronic rhinosinusitis presented with a purulent, foul-smelling nasal discharge and obstruction. One year earlier he had been treated with a dacryocystorhinostomy for nasolacrimal duct obstruction. During the procedure, bone wax had been used to control bleeding in the anterior upper nasal cavity. On computed tomographic imaging, a fat-density lesion was seen in the anterior upper sinonasal cavity and was found to be hypointense or signal-void on all magnetic resonance imaging sequences. The lesion, which proved to consist of bone wax, was surgically removed. Here, we present the imaging features of retained bone wax in a patient with clinically diagnosed chronic rhinosinusitis after dacryocystorhinostomy

Retained bone wax on CT at one year after dacryocystorhinostomy: A case report

Energy Technology Data Exchange (ETDEWEB)

Kim, Seung Hyun; Park, Dong Woo; Jeong, Jin Yeok [Guri Hospital, Hanyang University College of Medicine, Guri (Korea, Republic of); Lee, Jong Ah; Lee, Young Jun [Dept. of Radiology, Seoul Hospital, Hanyang University College of Medicine, Seoul (Korea, Republic of)

2015-09-15

A 71-year-old man with chronic rhinosinusitis presented with a purulent, foul-smelling nasal discharge and obstruction. One year earlier he had been treated with a dacryocystorhinostomy for nasolacrimal duct obstruction. During the procedure, bone wax had been used to control bleeding in the anterior upper nasal cavity. On computed tomographic imaging, a fat-density lesion was seen in the anterior upper sinonasal cavity and was found to be hypointense or signal-void on all magnetic resonance imaging sequences. The lesion, which proved to consist of bone wax, was surgically removed. Here, we present the imaging features of retained bone wax in a patient with clinically diagnosed chronic rhinosinusitis after dacryocystorhinostomy.

Hábitos de higiene bucal e utilização de serviços odontológicos em escolares de uma cidade da Região Sul do Brasil Oral hygiene habits and use of dental services among teenage students in a city in southern Brazil

Directory of Open Access Journals (Sweden)

Silvia Letícia Freddo

2008-09-01

Full Text Available Estudo transversal investigando associação entre hábitos de higiene bucal e utilização dos serviços odontológicos, fatores sócio-demográficos e relacionados ao estilo de vida em amostra representativa de 1.170 escolares de 7ª série do ensino municipal de Gravataí, Rio Grande do Sul, Brasil. A associação entre os desfechos e sexo; cor da pele; inserção sócio-econômica; estilo de vida sedentário; uso de álcool e tabaco; e consumo de balas, refrigerantes e chocolates foi investigada com regressão de Cox univariada. Entre os jovens estudados, 77,8% escovavam os dentes > 3 vezes/dia, 31,9% utilizavam fio dental, 68,9% visitavam o dentista anualmente e 50% consultaram por motivo curativo. As meninas apresentaram maior freqüência de escovação do que os meninos. Os jovens com baixa inserção sócio-econômica, os com estilo de vida sedentário e os que experimentaram tabaco apresentaram menor uso diário de fio dental e consultas odontológicas anuais, e mais consultas curativas. O consumo de balas associou-se à menor utilização de serviços odontológicos e o de refrigerantes à maior freqüência de consultas curativas. O estilo de vida saudável associou-se com melhores hábitos de higiene bucal e utilização de serviços odontológicos.This study evaluated oral hygiene habits and use of dental services among teenage students, and analyzed their association with sociodemographic factors and life styles. This cross-sectional study included a representative sample of 1,170 seventh-graders from municipal public schools of Gravataí, Rio Grande do Sul State, Brazil. The Cox regression model for univariate analysis, modified for cross-sectional studies, was used to analyze the association between variables. Of the adolescents included in the study, 77.8% brushed their teeth three or more times a day, 31.9% flossed daily, 68.9% visited the dentist regularly, and 50% visited the dentist for dental treatment. Tooth brushing was

A review of the performance and structural considerations of paraffin wax hybrid rocket fuels with additives

Science.gov (United States)

Veale, Kirsty; Adali, Sarp; Pitot, Jean; Brooks, Michael

2017-12-01

Paraffin wax as a hybrid rocket fuel has not been comprehensively characterised, especially regarding the structural feasibility of the material in launch applications. Preliminary structural testing has shown paraffin wax to be a brittle, low strength material, and at risk of failure under launch loading conditions. Structural enhancing additives have been identified, but their effect on motor performance has not always been considered, nor has any standard method of testing been identified between research institutes. A review of existing regression rate measurement techniques on paraffin wax based fuels and the results obtained with various additives are collated and discussed in this paper. The review includes 2D slab motors that enable visualisation of liquefying fuel droplet entrainment and the effect of an increased viscosity on the droplet entrainment mechanism, which can occur with the addition of structural enhancing polymers. An increased viscosity has been shown to reduce the regression rate of liquefying fuels. Viscosity increasing additives that have been tested include EVA and LDPE. Both these additives increase the structural properties of paraffin wax, where the elongation and UTS are improved. Other additives, such as metal hydrides, aluminium and boron generally offer improvements on the regression rate. However, very little consideration has been given to the structural effects these additives have on the wax grain. A 40% aluminised grain, for example, offers a slight increase in the UTS but reduces the elongation of paraffin wax. Geometrically accurate lab-scale motors have also been used to determine the regression rate properties of various additives in paraffin wax. A concise review of all available regression rate testing techniques and results on paraffin wax based hybrid propellants, as well as existing structural testing data, is presented in this paper.

Understanding nucleic acid structural changes by comparing wide-angle x-ray scattering (WAXS) experiments to molecular dynamics simulations

Energy Technology Data Exchange (ETDEWEB)

Pabit, Suzette A.; Katz, Andrea M.; Pollack, Lois [School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853 (United States); Tolokh, Igor S. [Department of Computer Science, Virginia Tech, Blacksburg, Virginia 24061 (United States); Drozdetski, Aleksander [Department of Physics, Virginia Tech, Blacksburg, Virginia 24061 (United States); Baker, Nathan [Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Onufriev, Alexey V. [Department of Computer Science, Virginia Tech, Blacksburg, Virginia 24061 (United States); Department of Physics, Virginia Tech, Blacksburg, Virginia 24061 (United States)

2016-05-28

Wide-angle x-ray scattering (WAXS) is emerging as a powerful tool for increasing the resolution of solution structure measurements of biomolecules. Compared to its better known complement, small angle x-ray scattering (SAXS), WAXS targets higher scattering angles and can enhance structural studies of molecules by accessing finer details of solution structures. Although the extension from SAXS to WAXS is easy to implement experimentally, the computational tools required to fully harness the power of WAXS are still under development. Currently, WAXS is employed to study structural changes and ligand binding in proteins; however, the methods are not as fully developed for nucleic acids. Here, we show how WAXS can qualitatively characterize nucleic acid structures as well as the small but significant structural changes driven by the addition of multivalent ions. We show the potential of WAXS to test all-atom molecular dynamics (MD) simulations and to provide insight into understanding how the trivalent ion cobalt(III) hexammine (CoHex) affects the structure of RNA and DNA helices. We find that MD simulations capture the RNA structural change that occurs due to addition of CoHex.

Modified paraffin wax for improvement of histological analysis efficiency.

Science.gov (United States)

Lim, Jin Ik; Lim, Kook-Jin; Choi, Jin-Young; Lee, Yong-Keun

2010-08-01

Paraffin wax is usually used as an embedding medium for histological analysis of natural tissue. However, it is not easy to obtain enough numbers of satisfactory sectioned slices because of the difference in mechanical properties between the paraffin and embedded tissue. We describe a modified paraffin wax that can improve the histological analysis efficiency of natural tissue, composed of paraffin and ethylene vinyl acetate (EVA) resin (0, 3, 5, and 10 wt %). Softening temperature of the paraffin/EVA media was similar to that of paraffin (50-60 degrees C). The paraffin/EVA media dissolved completely in xylene after 30 min at 50 degrees C. Physical properties such as the amount of load under the same compressive displacement, elastic recovery, and crystal intensity increased with increased EVA content. EVA medium (5 wt %) was regarded as an optimal composition, based on the sectioning efficiency measured by the numbers of unimpaired sectioned slices, amount of load under the same compressive displacement, and elastic recovery test. Based on the staining test of sectioned slices embedded in a 5 wt % EVA medium by hematoxylin and eosin (H&E), Masson trichrome (MT), and other staining tests, it was concluded that the modified paraffin wax can improve the histological analysis efficiency with various natural tissues. (c) 2010 Wiley-Liss, Inc.

Development of lamellar structures in natural waxes - an electron diffraction investigation

Energy Technology Data Exchange (ETDEWEB)

Dorset, Douglas L. [Electron Diffraction Department, Hauptman-Woodward Medical Research Institute, Inc., Buffalo, NY (United States)

1999-06-07

When they are recrystallized from the melt, natural plant or insect waxes tend to form solid phases with a nematic-like structure (i.e. a parallel array of polymethylene chains with little or no aggregation of the molecules into distinct layers). An electron diffraction study of carnauba wax and two types of beeswax has shown that the degree of molecular organization into lamellar structures can be enhanced by annealing in the presence of benzoic acid, which also acts as an epitaxial substrate. Nevertheless, the resultant layer structure in the annealed solid is not the same as that found for paraffin wax fractions refined from petroleum. Probably because of a small but significant fraction of a very long chain ingredient, the lamellar separation is incomplete, incorporating a number of 'bridging molecules' that span the nascent lamellar interface.The same phenomenon has been described recently for a low molecular weight polyethylene. (author)

Increased accumulation of cuticular wax and expression of lipid transfer protein in response to periodic drying events in leaves of tree tobacco.

Science.gov (United States)

Cameron, Kimberly D; Teece, Mark A; Smart, Lawrence B

2006-01-01

Cuticular wax deposition and composition affects drought tolerance and yield in plants. We examined the relationship between wax and dehydration stress by characterizing the leaf cuticular wax of tree tobacco (Nicotiana glauca L. Graham) grown under periodic dehydration stress. Total leaf cuticular wax load increased after each of three periods of dehydration stress using a CH2Cl2 extraction process. Overall, total wax load increased 1.5- to 2.5-fold, but composition of the wax was not altered. Homologous series of wax components were classified into organic groups; n-hentriacontane was the largest component (>75%) with alcohols and fatty acids representing drying event. Leaves excised from plants subjected to multiple drying events were more resistant to water loss compared to leaves excised from well-watered plants, indicating that there is a negative relationship between total wax load and epidermal conductance. Lipid transfer proteins (LTPs) are thought to be involved in the transfer of lipids through the extracellular matrix for the formation of cuticular wax. Using northern analysis, a 6-fold increase of tree tobacco LTP gene transcripts was observed after three drying events, providing further evidence that LTP is involved in cuticle deposition. The simplicity of wax composition and the dramatic wax bloom displayed by tree tobacco make this an excellent species in which to study the relationship between leaf wax deposition and drought tolerance.

Preparation and Characterization of Sugar Cane Wax Microspheres ...

African Journals Online (AJOL)

... and characterize indomethacin (IM) microspheres prepared with sugar cane wax microsperes. Methods: Microspheres were prepared by melt-emulsified dispersion and cooling-induced solidification method. The microspheres were characterized by scanning electron microscopy (SEM) and differntial scanning calorimetry ...

A review on wax printed microfluidic paper-based devices for international health.

Science.gov (United States)

Altundemir, S; Uguz, A K; Ulgen, K

2017-07-01

Paper-based microfluidics has attracted attention for the last ten years due to its advantages such as low sample volume requirement, ease of use, portability, high sensitivity, and no necessity to well-equipped laboratory equipment and well-trained manpower. These characteristics have made paper platforms a promising alternative for a variety of applications such as clinical diagnosis and quantitative analysis of chemical and biological substances. Among the wide range of fabrication methods for microfluidic paper-based analytical devices ( μ PADs), the wax printing method is suitable for high throughput production and requires only a commercial printer and a heating source to fabricate complex two or three-dimensional structures for multipurpose systems. μ PADs can be used by anyone for in situ diagnosis and analysis; therefore, wax printed μ PADs are promising especially in resource limited environments where people cannot get sensitive and fast diagnosis of their serious health problems and where food, water, and related products are not able to be screened for toxic elements. This review paper is focused on the applications of paper-based microfluidic devices fabricated by the wax printing technique and used for international health. Besides presenting the current limitations and advantages, the future directions of this technology including the commercial aspects are discussed. As a conclusion, the wax printing technology continues to overcome the current limitations and to be one of the promising fabrication techniques. In the near future, with the increase of the current interest of the industrial companies on the paper-based technology, the wax-printed paper-based platforms are expected to take place especially in the healthcare industry.

Simulation of temperature-pressure profiles and wax deposition in gas-lift wells

Directory of Open Access Journals (Sweden)

Sevic Snezana

2017-01-01

Full Text Available Gas-lift is an artificial lift method in which gas is injected down the tubing- -casing annulus and enters the production tubing through the gas-lift valves to reduce the hydrostatic pressure of the formation fluid column. The gas changes pressure, temperature and fluid composition profiles throughout the production tubing string. Temperature and pressure drop along with the fluid composition changes throughout the tubing string can lead to wax, asphaltenes and inorganic salts deposition, increased emulsion stability and hydrate formation. This paper presents a new model that can sucesfully simulate temperature and pressure profiles and fluid composition changes in oil well that operates by means of gas-lift. This new model includes a pipe-in-pipe segment (production tubing inside production casing, countercurrent flow of gas-lift gas and producing fluid, heat exchange between gas-lift gas and the surrounding ambient – ground; and gas-lift gas with the fluid in the tubing. The model enables a better understanding of the multiphase fluid flow up the production tubing. Model was used to get insight into severity and locations of wax deposition. The obtained information on wax deposition can be used to plan the frequency and depth of wax removing operations. Model was developed using Aspen HYSYS software.

Catalytic cracking of slack wax with molten mixtures containing aluminum chloride and bromide. [Wax obtained in the process of dewaxing lubricating oils

Energy Technology Data Exchange (ETDEWEB)

Ohtsuka, Y; Oizumi, K; Tamai, Y

1983-09-01

The catalytic cracking of slack wax with molten mixtures of AlCl/sub 3/ (aluminum chloride) and AlBr/sub 3/ (aluminum bromide) was investigated in an atmospheric semi-batch reactor at low temperatures of 100 to 160/sup 0/C. The cracking rate was proportional to the amount of unreacted wax. The conversion at 135/sup 0/C reached 25 wt % under typical reaction conditions. About 95 wt % of the cracking products consisted of isobutane, 2-methylbutane, and methylpentanes, ca. 50% of these isoparaffins being isobutane. The difference in cracking activity between this catalyst and a solid acid catalyst is discussed based on the product distribution. Hardly any reaction took place without HCl, which shows that the presence of HCl is essential for this cracking. The cracking rate increased sharply with an increase in the amount of the catalyst. The rate did not depend on the composition of the AlCl/sub 3//sup -/ AlBr/sub 3/ catalyst, but the product distribution did depend on it and the content of the gasoline fraction in the products increased with an increase in the concentration of AlBr/sub 3/. The cracking residue was characterized by IR and NMR spectroscopy. The results show that the cracking reaction probably occurs heterogeneously at the interface between the liquid wax and the molten catalyst. 3 figures, 4 tables.

Development and Properties of a Wax Ester Hydrolase in the Cotyledons of Jojoba Seedlings 1

Science.gov (United States)

Huang, Anthony H. C.; Moreau, Robert A.; Liu, Kitty D. F.

1978-01-01

The activity of a wax ester hydrolase in the cotyledons of jojoba (Simmondsia chinensis) seedlings increased drastically during germination, parallel to the development of the gluconeogenic process. The enzyme at its peak of development was obtained in association with the wax body membrane, and its properties were studied. It had an optimal activity at alkaline pH (8.5-9). The apparent Km value for N-methylindoxylmyristate was 93 μM. It was stable at 40 C for 30 min but was inactivated at higher temperature. Various divalent cations and ethylenediaminetetraacetate had little effect on the activity. p-Chloromercuribenzoate was a strong inhibitor of the enzyme activity, and its effect was reversed by subsequent addition of dithiothreitol. It had a broad substrate specificity with highest activities on monoglycerides, wax esters, and the native substrate (jojoba wax). PMID:16660288

Printed wax masks for 254 nm deep-UV pattering of PMMA-based microfluidics

International Nuclear Information System (INIS)

Fan, Yiqiang; Liu, Yang; Li, Huawei; Foulds, Ian G

2012-01-01

This paper reports a new technique for masking deep-UV exposure of poly(methyl methacrylate) (PMMA) using a printed wax mask. This technique provides an inexpensive and bulk fabrication method for PMMA structures. The technique involves the direct printing of the mask onto a polymer sheet using a commercial wax printer. The wax layer was then transferred to a PMMA substrate using a thermal laminator, exposed using deep-UV (with a wavelength of 254 nm), developed in an IPA:water solution, and completed by bonding on a PMMA cap layer. A sample microfluidic device fabricated with this method is also presented, with the microchannel as narrow as 50 µm. The whole process is easy to perform without the requirement for any microfabrication facilities. (technical note)

Particulate pollutants are capable to 'degrade' epicuticular waxes and to decrease the drought tolerance of Scots pine (Pinus sylvestris L.).

Science.gov (United States)

Burkhardt, Juergen; Pariyar, Shyam

2014-01-01

Air pollution causes the amorphous appearance of epicuticular waxes in conifers, usually called wax 'degradation' or 'erosion', which is often correlated with tree damage symptoms, e.g., winter desiccation. Previous investigations concentrated on wax chemistry, with little success. Here, we address the hypothesis that both 'wax degradation' and decreasing drought tolerance of trees may result from physical factors following the deposition of salt particles onto the needles. Pine seedlings were sprayed with dry aerosols or 50 mM solutions of different salts. The needles underwent humidity changes within an environmental scanning electron microscope, causing salt expansion on the surface and into the epistomatal chambers. The development of amorphous wax appearance by deliquescent salts covering tubular wax fibrils was demonstrated. The minimum epidermal conductance of the sprayed pine seedlings increased. Aerosol deposition potentially 'degrades' waxes and decreases tree drought tolerance. These effects have not been adequately considered thus far in air pollution research. Copyright © 2013 Elsevier Ltd. All rights reserved.

Online estimation of wax deposition thickness in single-phase sub-sea pipelines based on acoustic chemometrics: A feasibility study

OpenAIRE

Halstensen, Maths; Arvoh, Benjamin Kaku; Amundsen, Lene; Hoffmann, Rainer

2012-01-01

Wax deposition in sub-sea oil producing pipelines is a concern to the oil producing companies. The deposition of wax in pipelines can cause serious economic implications if not monitored and controlled. Several researchers have developed models and investigated the deposition of wax in crude oil pipelines. As of today, there is no off the shelf instrument available for reliable online estimation of the wax depo- sition thickness in sub-sea pipelines. Acoustic chemometrics was applied to inves...

Flow and linear coefficient of thermal expansion of four types of Base Plate waxes compared with ADA standard

Directory of Open Access Journals (Sweden)

Monzavi A

2002-07-01

Full Text Available Waxes have a lot of applications in dentistry. Such materials are of thermoplastic type that undergoes deformation in different temperatures. Two important properties of base plate waxes are flow and their coefficient of linear thermal expansion. Recently, different institutions, inside the country, produce dentistry waxes, while they have not been standardized. Consequently, consumers' dissatisfaction are observed. In this research, the two above- mentioned factors were compared between three kinds of Iranian waxes with Cavex that is foreign production, based on test number 24 of ADA. To measure the flow rate in the temperatures of 23, 37 and 45°c, Wilcoxon statistical analysis was used. The results showed that in 23°c, the flow rate of Cavex and Azardent waxes met ADA standards; however, it was not true for two others types. In 37°c, the flow of none of the waxes was standardized and in 45°c their flow was acceptable, moreover, thermal expansion coefficient, for Cavex and Azardent types, was based on ADA standard.

Evaluation of methods for wax determination in crude oil; Avaliacao de metodos de determinacao de parafinas em petroleo

Energy Technology Data Exchange (ETDEWEB)

Dias, Julio Cesar M.; Silva, Maria do Socorro A.J. da; Vasconcellos, Rosa C.U. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas; Tamanqueira, Juliana B. [Fundacao Gorceix, Ouro Preto, MG (Brazil)

2008-07-01

Determining the wax content of crude oil is of great importance for petroleum industry, especially for production, storage and transportation of crude oils. Many different methodologies of wax determining are available in the technical literature. However, the selection of the most suitable method must be in accordance with the aim of the analysis and observing the specificities of each technique. The purpose of this work was to determine the performance of different techniques of wax determining applied to characterization of precipitation properties of waxy compounds in crude oils. Twelve samples of crude oils proceeding from the main Brazilian oil producing sedimentary basins were selected for this study. These samples were analyzed by three important analytical techniques of wax determining: precipitation by cooled solvent; liquid chromatography with precipitation by cooled solvent; and liquid chromatography followed by gas chromatography. Differential scanning calorimetry data related to the wax crystallization in these oils were used as parameters of validation. The results obtained in this study indicate that the liquid chromatography followed by gas chromatography method has the best performance for wax determining in crude oils. (author)

Effect of asphaltenes on crude oil wax crystallization

DEFF Research Database (Denmark)

Kriz, Pavel; Andersen, Simon Ivar

2005-01-01

The paper summarizes the experimental work done on asphaltene influenced wax crystallization. Three different asphaltenes (from stable oil, instable oil, and deposit) were mixed at several concentrations or dispersions into the waxy crude oil. These blends were evaluated by viscometry and yield s...

Metabolism of dietary fatty alcohol, fatty acid, and wax ester in carp

International Nuclear Information System (INIS)

Mankura, Mitsumasa; Kayama, Mitsu; Iijima, Noriaki.

1987-01-01

Lipids in various tissues of the carp, Cyprinus carpio were analyzed. The fates of force-fed [1- 14 C]palmitic acids, [1- 14 C]cetyl alcohol, and oleyl[1- 14 C]linoleate, were compared with those given in vitro experiments. Major lipid classes in all except adipose tissue were found to be polar lipids (phospholipids) and triacylglycerols. The major fatty acids in nearly all the tissues were 16 : 0, 18 : 1, 18 : 2, and 22 : 6. Although the radioactivity incorporation into wax esters from [1- 14 C]palmitic acid and [1- 14 C]cetyl alcohol for various tissue homogenates was quite high, in vivo incorporation of these labelled compounds into wax esters was very low and radioactivity was distributed mainly in the lipids of muscle, skin, hepatopancreas, intestine, and gill. Almost all the radioactivity in various tissues was present in phospatidylcholine and triacylglycerols. Most of the oleyl[1- 14 C]linoleate was easily hydrolyzed by various tissue homogenates. Force-fed oleyl[1- 14 C]linoleate was hydrolyzed in the intestine and then transported to other tissues, such as muscle, kin, gill, and hepatopancreas. Moreover, released radioactivity from oleyl[1- 14 C]linoleate was present in mainly phosphatidylcholine and triacylglycerols. Radioactivity was also detected in wax esters in plasma. Certain amounts for fatty acids released from [1- 14 C]triolein in the hepatopancreas homogenates were incorporated into wax esters; this was stimulated by the addition of oleyl alcohol. The present results indicate extensive hydrolysis of wax ester to possibly occur in the intestine and certain portions of the fatty alcohol moiety to be resterfied. The portions may be oxidized to fatty acids and which subsequently behave as dietary fatty acids. (author) 50 ref

Influence of putrescine and carnauba wax on functional and sensory quality of pomegranate (Punica granatum L.) fruits during storage.

Science.gov (United States)

Barman, Kalyan; Asrey, Ram; Pal, R K; Kaur, Charanjit; Jha, S K

2014-01-01

Functional properties (anthocyanins, antioxidant, ascorbic acid and tannin) and sensory score were determined in pomegranate fruits at two storage temperatures (3 and 5 °C) after treatment with 2 mM putrescine and 1 : 10 carnauba wax (carnauba wax : water). The treatments (putrescine and carnauba wax) were given by immersion method followed by storage up to 60 days. Both treatments retained significantly higher anthocyanins, antioxidant, ascorbic acid, tannin and sensory qualities as compared with control fruits under both the storage conditions. Combined application of putrescine + carnauba wax showed better response in retaining functional properties than putrescine treated or nontreated fruits. The impacts of putrescine and carnauba wax treatments were found more pronounced after 30 days at 3-5 °C storage temperature in retaining functional and sensory qualities. After 60 days of storage, putrescine + carnauba wax retained about 25% higher antioxidant activity both at 3 and 5 °C storage temperatures.

Printed wax masks for 254 nm deep-UV pattering of PMMA-based microfluidics

KAUST Repository

Fan, Yiqiang

2012-01-13

This paper reports a new technique for masking deep-UV exposure of poly(methyl methacrylate) (PMMA) using a printed wax mask. This technique provides an inexpensive and bulk fabrication method for PMMA structures. The technique involves the direct printing of the mask onto a polymer sheet using a commercial wax printer. The wax layer was then transferred to a PMMA substrate using a thermal laminator, exposed using deep-UV (with a wavelength of 254 nm), developed in an IPA:water solution, and completed by bonding on a PMMA cap layer. A sample microfluidic device fabricated with this method is also presented, with the microchannel as narrow as 50 μm. The whole process is easy to perform without the requirement for any microfabrication facilities. © 2012 IOP Publishing Ltd.

Analyzing radiation absorption difference of dental substance by using Dual CT

Science.gov (United States)

Yu, H.; Lee, H. K.; Cho, J. H.; Yang, H. J.; Ju, Y. S.

2015-07-01

The purpose of this study was to evaluate the changes of noise and computer tomography (CT) number in each dental substance, by using the metal artefact reduction algorithm; we used dual CT for this study. For the study, we produced resin, titanium, gypsum, and wax that are widely used by dentists. In addition, we made nickel to increase the artefact. While making the study materials, we made sure that there is no difficulty when inserting the substances inside phantom. In order to study, we scanned before and after using the metal artefact reduction algorithm. We conducted an average analysis of CT number and noise, before and after using the metal artefact reduction algorithm. As a result, there was no difference in CT number and noise before and after using the metal artefact reduction algorithm. However, when it comes to the noise value in each substance, wax's noise value was the lowest whereas titanium's noise value was the highest, after applying the metal artefact reduction algorithm. In nickel, CT number and noise value from artefact area showed a decreased noise value when applying the metal artefact reduction algorithm. In conclusion, we assumed that we could increase the effectiveness of CT examination by applying dual energy's metal artefact reduction algorithm.

Effects of irradiation in combination with waxing on the essential oils in orange peel

International Nuclear Information System (INIS)

Moussaid, M.; Lacroix, M.; Nketsia-Tabiri, J.; Boubekri, C.

2000-01-01

The study evaluated the effects of waxing and irradiation dose on the essential oils in orange peel. Mature oranges (Maroc late) waxed or unwaxed were treated with 0-2 kGy radiation. Volatiles in the peel were extracted and analyzed by G.C. D-limonene was significantly lower (P≤0.05) in waxed oranges; levels in samples treated with 2 kGy were higher than those treated with 0 or 1 kGy. Linalool, methyl anthranilate and 3.7-dimethyl-2.6-octadienal decreased as the dose increased. The analysis of variance indicates that only linalool was influenced by post-irradiation storage time. The level of this compound increased with storage time. (author)

Development of the cuticular wax during growth of Kalanchoe daigremontiana (Hamet et Perr. de la Bathie) leaves.

Science.gov (United States)

Van Maarseveen, Clare; Han, Hong; Jetter, Reinhard

2009-01-01

The goal of the present study was to monitor cuticular wax accumulation during leaf development of Kalanchoe daigremontiana. Leaves expanded linearly until they were 40-60 d old. Wax coverages of leaves on the third node increased steadily during initial leaf development, from 6.5 microg x cm(-2) on day 22 to 15.3 microg x cm(-2) on day 53, and then levelled off. Triterpenoids dominated the wax mixture throughout leaf development, but decreased from 74 to 40-45% in mature leaves, while very long-chain fatty acid (VLCFA) derivatives increased from 19 to 39-44%. The major VLCFA derivatives were alkanes, accompanied by fatty acids, primary alcohols, aldehydes and alkyl esters. In all compound classes, either C(34) or C(33) homologs predominated during leaf development. Eight different triterpenoids were identified, with glutinol constituting 70% of the fraction, and friedelin (20%) and germanicol (10%) as further major components of the young leaf wax. The glutinol percentage decreased, while the relative amounts of epifriedelanol and glutanol increased during development. Various leaf pairs upwards from the third node showed similar growth patterns and developmental time courses of cuticular wax amounts and composition. Based on these surface chemical analyses, the relative activities of biosynthetic pathways leading to various wax components can be assessed.

ETHNOECOLOGY AND ETHNOBOTANY OF THE PALM CARNAUBA WAX IN BRAZILIAN SEMI-ARID

OpenAIRE

Rodrigo Ferreira de Sousa; Richeliel Albert Rodrigues Silva; Talita Geovanna Fernandes Rocha; José Augusto da Silva Santana; Fábio de Almeida Vieira

2015-01-01

The aim of this study was to investigate aspects of ethnoecological and ethnobotanical of carnauba wax (Copernicia prunifera (Miller) H. E. Moore, Arecaceae) in an extractive community of municipality of Ipanguaçu, Rio Grande do Norte state. We interviewed key informants, using the technique of inducing nonspecific, guided tour and direct observation to confirm the data. According to most residents of Pedro Ezequiel Araújo community, the area of carnauba wax in the region is natural. In the r...

Epicuticular wax on stomata of damaged silver fir trees (Abies alba Mili.)

OpenAIRE

Tomislav Bačić; Ljiljana Krstin; Jadranka Roša; Željko Popović

2011-01-01

Condition of epistomatal wax on the abaxial surface of the current and previous-year needles of damaged silver fir trees (Abies alba Mill.), both from the polluted Risnjak and "clean" Donja Dobra sites in Gorski Kotar region, both influenced by pollutants coming from Europe, during two years, three times a year, were examined with Scanning Electron Microscope. In the course of time the wax tubules on the epistomatal rims of stomata in polluted, but also in "clean" needles surface, become fuse...

Flipping a Dental Anatomy Course: A Retrospective Study Over Four Years

Directory of Open Access Journals (Sweden)

Mahmoud M. Bakr

2016-01-01

Full Text Available Flipped classrooms have been successfully used to increase student engagement and support student learning in a range of educational fields, including health education. These advantages for student learning supported implementation of the flipped classroom in introductory sciences and preclinical courses in dental education. We report on a 4-year retrospective study which compared two methods of delivery of a first-year dental anatomy course. The first method used the traditional method, consisting of face to face contact teaching hours, which was compared to a partial flipped classroom, where lecture contact was maintained but practical classes were flipped. A series of online videos demonstrating different practical tasks such as wax carving and tooth identification. An online digital library and online quizzes for self-reflected learning were developed and trialled. Students’ Evaluations of Course (SEC and students’ overall performance in practical and theoretical assessments were used to evaluate the impact on student engagement and success, respectively, after implementation of the modified course offerings. This study evidences the success of the transition to a partially flipped course design. Careful design and consideration of implementation of the flipped classroom method in dental education are recommended to ensure that there is reliable availability of online resources and dedicated teaching staff for construction of resources and delivery of relevant in-class activities.

De novo assembly and characterization of the transcriptome, and development of SSR markers in wax gourd (Benicasa hispida.

Directory of Open Access Journals (Sweden)

Biao Jiang

Full Text Available BACKGROUND: Wax gourd is a widely used vegetable of Cucuribtaceae, and also has important medicinal and health values. However, the genomic resources of wax gourd were scarcity, and only a few nucleotide sequences could be obtained in public databases. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we examined transcriptome in wax gourd. More than 44 million of high quality reads were generated from five different tissues of wax gourd using Illumina paired-end sequencing technology. Approximately 4 Gbp data were generated, and de novo assembled into 65,059 unigenes, with an N50 of 1,132 bp. Based on sequence similarity search with known protein database, 36,070 (55.4% showed significant similarity to known proteins in Nr database, and 24,969 (38.4% had BLAST hits in Swiss-Prot database. Among the annotated unigenes, 14,994 of wax gourd unigenes were assigned to GO term annotation, and 23,977 were found to have COG classifications. In addition, a total of 18,713 unigenes were assigned to 281 KEGG pathways. Furthermore, 6,242 microsatellites (simple sequence repeats were detected as potential molecular markers in wax gourd. Two hundred primer pairs for SSRs were designed for validation of the amplification and polymorphism. The result showed that 170 of the 200 primer pairs were successfully amplified and 49 (28.8% of them exhibited polymorphisms. CONCLUSION/SIGNIFICANCE: Our study enriches the genomic resources of wax gourd and provides powerful information for future studies. The availability of this ample amount of information about the transcriptome and SSRs in wax gourd could serve as valuable basis for studies on the physiology, biochemistry, molecular genetics and molecular breeding of this important vegetable crop.

Gourds: Bitter, Bottle, Wax, Snake, Sponge and Ridge

Science.gov (United States)

Minor cucurbits include bitter gourd, bottle gourd, wax gourd, snake gourd, and sponge and ridge gourd, which are significant dietary sources of nutrients such as vitamin A and C, iron and calcium. These cucurbits are cultivated and marketed by smallholder farmers and remain important components of ...

Effect of new type of synthetic waxes on reduced production and compaction temperature of asphalt mixture with reclaimed asphalt

Science.gov (United States)

Valentová, Tereza; Benešová, Lucie; Mastný, Jan; Valentin, Jan

2017-09-01

Lower mixing and paving temperatures of asphalt mixtures, which are an important issue in recent years, with respect to increased energy demand of civil engineering structures during their processing, allow reduction of this demand and result in minimized greenhouse gas production. In present time, there are many possibilities how to achieve reduction of production temperature during the mixing and paving of an asphalt mixture. The existing solutions distinguish in target operating temperature behaviour which has to be achieved in terms of good workability. This paper is focused on technical solutions based on use of new types of selected synthetic and bio-based waxes. In case of bio-based additive sugar cane wax was used, which is free of paraffins and is reclaimed as waste product during processing of sugar cane. The used waxes are added to bituminous binder in form of free-flowing granules or fine-grained powder. Synthetic waxes are represented by new series of Fischer-Tropsch wax in form of fine granules as well as by polyethylene waxes in form of fine-grained powder or granules. Those waxes were used to modify a standard paving grade bitumen dosed into asphalt mixture of ACsurf type containing up to 30 % of reclaimed asphalt (RA).

Effect of high dose SO2 and ethylene exposure on the structure of epicuticular wax of picea pungens

International Nuclear Information System (INIS)

Patrie, J.; Berg, V.

1994-01-01

Conifers in polluted air generally exhibit accelerated degradation of epicuticular wax, but it is not clear whether the change is due to direct exposure to the pollutant or some other mechanism. Needles from blue spruce (Picea pungens) were exposed to sulfur dioxide or ethylene gas at 0 to 10,000 microliters per liter for 2 to 196 h; samples were examined by scanning electron microscopy. Neither gas caused changes in the wax crystals, although late in the growing season a fungal infestation was associated with degradation of wax structures. This supports hypotheses explaining accelerated epicuticular wax degradation by indirect effects of exposure to air pollutants. (orig.)

Testing a Novel 3D Printed Radiographic Imaging Device for Use in Forensic Odontology.

Science.gov (United States)

Newcomb, Tara L; Bruhn, Ann M; Giles, Bridget; Garcia, Hector M; Diawara, Norou

2017-01-01

There are specific challenges related to forensic dental radiology and difficulties in aligning X-ray equipment to teeth of interest. Researchers used 3D printing to create a new device, the combined holding and aiming device (CHAD), to address the positioning limitations of current dental X-ray devices. Participants (N = 24) used the CHAD, soft dental wax, and a modified external aiming device (MEAD) to determine device preference, radiographer's efficiency, and technique errors. Each participant exposed six X-rays per device for a total of 432 X-rays scored. A significant difference was found at the 0.05 level between the three devices (p = 0.0015), with the MEAD having the least amount of total errors and soft dental wax taking the least amount of time. Total errors were highest when participants used soft dental wax-both the MEAD and the CHAD performed best overall. Further research in forensic dental radiology and use of holding devices is needed. © 2016 American Academy of Forensic Sciences.

Surfactant-free carnauba wax dispersion and its use for layer-by-layer assembled protective surface coatings on wood

International Nuclear Information System (INIS)

Lozhechnikova, Alina; Bellanger, Hervé; Michen, Benjamin; Burgert, Ingo; Österberg, Monika

2017-01-01

Highlights: • A facile sonication route to produce aqueous wax dispersions is developed. • The wax dispersion is naturally stable and free of surfactants or stabilizers. • Wax and ZnO particles are coated onto wood using layer-by-layer assembly. • The coating brings superhydrophobicity while preserving moisture buffering. • ZnO improves the color stability of wood to UV light. - Abstract: Protection from liquid water and UV radiation are equally important, and a sophisticated approach is needed when developing surface coatings that preserve the natural and well-appreciated aesthetic appearance of wood. In order to prevent degradation and prolong the service life of timber, a protective coating was assembled using carnauba wax particles and zinc oxide nanoparticles via layer-by-layer deposition in water. For this purpose, a facile sonication route was developed to produce aqueous wax dispersion without any surfactants or stabilizers. The suspension was stable above pH 4 due to the electrostatic repulsion between the negatively charged wax particles. The particle size could be controlled by the initial wax concentration with average particle sizes ranging from 260 to 360 nm for 1 and 10 g/L, respectively. The deposition of wax particles onto the surface of spruce wood introduced additional roughness to the wood surface at micron level, while zinc oxide provided nano roughness and UV-absorbing properties. In addition to making wood superhydrophobic, this novel multilayer coating enhanced the natural moisture buffering capability of spruce. Moreover, wood surfaces prepared in this fashion showed a significant reduction in color change after exposure to UV light. A degradation of the wax through photocatalytic activity of the ZnO particles was measured by FTIR, indicating that further studies are required to achieve long-term stability. Nevertheless, the developed coating showed a unique combination of superhydrophobicity and excellent moisture buffering

Surfactant-free carnauba wax dispersion and its use for layer-by-layer assembled protective surface coatings on wood

Energy Technology Data Exchange (ETDEWEB)

Lozhechnikova, Alina [Department of Forest Products Technology, School of Chemical Technology, Aalto University, P.O. Box 16300, FI-00076, Aalto (Finland); Bellanger, Hervé; Michen, Benjamin; Burgert, Ingo [Institute for Building Materials (IfB), Wood Materials Science, ETH Zürich, Stefano-Franscini-Platz 3, 8093 Zürich (Switzerland); Applied Wood Materials Laboratory, Empa − Swiss Federal Laboratories for Material Testing and Research, 8600 Dübendorf (Switzerland); Österberg, Monika, E-mail: monika.osterberg@aalto.fi [Department of Forest Products Technology, School of Chemical Technology, Aalto University, P.O. Box 16300, FI-00076, Aalto (Finland)

2017-02-28

Highlights: • A facile sonication route to produce aqueous wax dispersions is developed. • The wax dispersion is naturally stable and free of surfactants or stabilizers. • Wax and ZnO particles are coated onto wood using layer-by-layer assembly. • The coating brings superhydrophobicity while preserving moisture buffering. • ZnO improves the color stability of wood to UV light. - Abstract: Protection from liquid water and UV radiation are equally important, and a sophisticated approach is needed when developing surface coatings that preserve the natural and well-appreciated aesthetic appearance of wood. In order to prevent degradation and prolong the service life of timber, a protective coating was assembled using carnauba wax particles and zinc oxide nanoparticles via layer-by-layer deposition in water. For this purpose, a facile sonication route was developed to produce aqueous wax dispersion without any surfactants or stabilizers. The suspension was stable above pH 4 due to the electrostatic repulsion between the negatively charged wax particles. The particle size could be controlled by the initial wax concentration with average particle sizes ranging from 260 to 360 nm for 1 and 10 g/L, respectively. The deposition of wax particles onto the surface of spruce wood introduced additional roughness to the wood surface at micron level, while zinc oxide provided nano roughness and UV-absorbing properties. In addition to making wood superhydrophobic, this novel multilayer coating enhanced the natural moisture buffering capability of spruce. Moreover, wood surfaces prepared in this fashion showed a significant reduction in color change after exposure to UV light. A degradation of the wax through photocatalytic activity of the ZnO particles was measured by FTIR, indicating that further studies are required to achieve long-term stability. Nevertheless, the developed coating showed a unique combination of superhydrophobicity and excellent moisture buffering

The analysis of the wax foundry models fabrication process for the CPX3000 device

Directory of Open Access Journals (Sweden)

G. Budzik

2011-04-01

Full Text Available The paper presents possibilities of creating wax founding models by means of CPX3000 device. The device is used for Rapid Prototypingof models made of foundry wax in an incremental process. The paper also presents problems connected with choosing technologicalparameters for incremental shaping which influence the accuracy of created models. Issues connected with post-processing are alsodescribed. This process is of great importance for obtaining geometrically correct models. The analysis of parameters of cleaning models from supporting material is also presented. At present CPX3000 printer is the first used in Poland device by 3D Systems firm for creating wax models. The printer is at The Faculty of Mechanical Engineering at Rzeszów University of Technology.

Morphology and accumulation of epicuticular wax on needles of Douglas-fir (Pseudotsuga menziesii var. menziesii)

Science.gov (United States)

Constance A. Harrington; William C. Carlson

2015-01-01

Past studies have documented differences in epicuticular wax among several tree species but little attention has been paid to changes in accumulation of foliar wax that can occur during the year. We sampled current-year needles from the terminal shoots of Douglas-fir (Pseudotsuga menziesii var. menziesii) in late June/early...

Identification of In-Chain-Functionalized Compounds and Methyl-Branched Alkanes in Cuticular Waxes of Triticum aestivum cv. Bethlehem.

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Radu C Racovita

Full Text Available In this work, cuticular waxes from flag leaf blades and peduncles of Triticum aestivum cv. Bethlehem were investigated in search for novel wax compounds. Seven wax compound classes were detected that had previously not been reported, and their structures were elucidated using gas chromatography-mass spectrometry of various derivatives. Six of the classes were identified as series of homologs differing by two methylene units, while the seventh was a homologous series with homologs with single methylene unit differences. In the waxes of flag leaf blades, secondary alcohols (predominantly C27 and C33, primary/secondary diols (predominantly C28 and esters of primary/secondary diols (predominantly C50, combining C28 diol with C22 acid were found, all sharing similar secondary hydroxyl group positions at and around C-12 or ω-12. 7- and 8-hydroxy-2-alkanol esters (predominantly C35, 7- and 8-oxo-2-alkanol esters (predominantly C35, and 4-alkylbutan-4-olides (predominantly C28 were found both in flag leaf and peduncle wax mixtures. Finally, a series of even- and odd-numbered alkane homologs was identified in both leaf and peduncle waxes, with an internal methyl branch preferentially on C-11 and C-13 of homologs with even total carbon number and on C-12 of odd-numbered homologs. Biosynthetic pathways are suggested for all compounds, based on common structural features and matching chain length profiles with other wheat wax compound classes.

EPICUTICULAR WAX COMPOSITION OF SOME EUROPEAN SEDUM SPECIES

NARCIS (Netherlands)

STEVENS, JF; THART, H; BOLCK, A; ZWAVING, JH; MALINGRE, TM

Epicuticular waxes from 30 species of Sedum and 2 species of Sempervivoideae, i.e. Aeonium spathulatum and Sempervivum nevadense, have been analysed by GC and GC-MS. The Sedum taxa examined were S. acre, S. album, S. series Alpestria (13 species), S. anglicum, S. brevifolium, S. litoreum, S. lydium,

Self-Reported Halitosis in relation to Oral Hygiene Practices, Oral Health Status, General Health Problems, and Multifactorial Characteristics among Workers in Ilala and Temeke Municipals, Tanzania

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C. M. Kayombo

2017-01-01

Full Text Available Aim. To assess self-reported halitosis, oral hygiene practices, oral health conditions, general health problems, sociodemographic factors, and behavioural and psychological characteristics among workers in Ilala and Temeke municipals. Materials and Methods. This was a cross-sectional descriptive study. Four hundred workers were recruited using a self-administered structured questionnaire. Results. Self-reported tooth brushing practice was 100%, tongue cleaning 58.5%, dental flossing 4.3%, gum bleeding on tooth brushing 79.3%, presence of hard deposits on teeth 32%, mobile teeth 15.3%, and self-reported halitosis (SRH 48.5%. Tea users were 95%, coffee users 75.8%, smokers 21%, and alcohol consumers 47%. The SRH was significantly associated with bleeding gums, hard deposits, and mobile and malaligned teeth. Tongue cleaning and regular change of toothbrush were associated with low prevalence of SRH (P<0.001. Higher occurrence of SRH was significantly related to low education and smoking. Conclusion. Self-reported halitosis was prevalent among workers and was significantly associated with bleeding gums, hard dental deposits, mobile teeth, and smoking. All participants brushed their teeth and cleaned the tongue regularly but use of dental floss was extremely low. Oral health education and health promotion are recommended.

19 (No. 1)

African Journals Online (AJOL)

Hamoonga A, Anthony S.A., Siziya S. Knowledge, Attitudes and Practices on Oral hygiene among 12 years old ... teeth twice or more in a day and while (0.3%) reported to use dental floss as tooth cleaning gadget. ... state their parents' role on oral health of the child .... companies and in media advertisements hence.

The role of health behavior in preventing dental caries in resource-poor adults: a pilot intervention.

Science.gov (United States)

Wu, Andrew; Switzer-Nadasdi, Rhonda

2014-01-01

Dental caries is a highly prevalent, yet preventable disease that is commonly overlooked in the adult population. It is strongly related to health-related behaviors and knowledge, and therefore, is potentially receptive to a behavioral health intervention. However, prevention strategies that target health behaviors in adults are fundamentally different from those in children, whom most current intervention strategies for dental caries target. This study attempts to pilot design, implement, and assess health behavior intervention tools for adults, in order to improve their oral health. To increase knowledge about dental caries by 80% and increase positive self-reported oral hygiene behaviors by 80% in low-income adult participants at Interfaith Dental Clinic by piloting novel interventional and educational tools based on the Transtheoretical Model of Health Behavior. A convenience sample of newly registered participants to the Interfaith Dental Clinic between August 2011 and May 2013, were interviewed on each participant's first appointment, exposed to the interventional tools, and subsequently interviewed at their next appointment. A control group, comprised of participants who had completed their caries care as deemed by the clinic and had not been exposed to the interventional tools, were also interviewed on their last appointment before graduating the clinic's program. A total of 112 participants were exposed to the intervention, and forty-two participants comprised the control group. Follow-up for the intervention group was 20.5% (n = 23). Knowledge about the cause of caries increased by 29.9%, and positive self-reported oral hygiene behaviors increased by 25.4%. A Wilcoxon rank sum test showed no significance between the interview scores of the post-intervention group and that of the control group (p = 0.18 for knowledge, p = 0.284 for behaviors). Qualitative results show the vast majority of participants blamed diet for cause of caries, that this participant

Psychological, behavioral, and clinical effects of intra-oral camera: a randomized control trial on adults with gingivitis.

Science.gov (United States)

Araújo, Mário-Rui; Alvarez, Maria-João; Godinho, Cristina A; Pereira, Cícero

2016-12-01

To evaluate the effects of using an intra-oral camera (IOC) during supportive periodontal therapy (SPT), on the psychological, behavioral, and clinical parameters of patients with gingivitis, outlined by evidence and a theory-based framework. A group of 78 adult patients with gingivitis receiving an SPT was randomized into two groups: IOC and control. Bleeding on Marginal Probing (BOMP), self-reported dental hygiene behaviors, and psychological determinants of behavior change (outcome expectancies, self-efficacy, and planning) and IOC opinion were evaluated 1 week before or during the appointment and 4 months later. Repeated-measures anova was used to compare groups over time. Almost all the patients brushed their teeth daily, while 78% either never or hardly ever used dental floss. The IOC group showed significant improvements in BOMP index (P < 0.001), self-reported flossing (P < 0.05), and self-efficacy (P < 0.05) compared to the control group. The use of IOC significantly improves clinical, behavioral, and psychological determinants of periodontal health 4 months after treatment. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Bee waxes: a model of characterization for using as base simulator tissue in teletherapy with photons

International Nuclear Information System (INIS)

Silva, Rogerio Matias Vidal da; Souza, Divanizia do Nascimento

2011-01-01

This paper presents a model of characterization and selection of bee waxes which makes possible to certify the usage viability of that base simulator tissue in the manufacture of appropriated objects for external radiotherapy with mega volt photon beams. The work was divide into three stages, where was evaluated physical and chemical properties besides the aspects related to the capacity of beam attenuation. All the process was carefully accompanied related to the wax origin such as the bee specimen and the flora surrounding the beehives. The chemical composition of the waxes is similar to others simulators usually used in radiotherapy. The behavior of mass attenuation coefficient in the radiotherapeutic energy range is comparable to other simulators, and consequently to the soft tissue. The proposed model is efficient and allows the affirmative that the usage of determined bee wax as base simulator tissue is convenient

Particulate pollutants are capable to ‘degrade’ epicuticular waxes and to decrease the drought tolerance of Scots pine (Pinus sylvestris L.)

International Nuclear Information System (INIS)

Burkhardt, Juergen; Pariyar, Shyam

2014-01-01

Air pollution causes the amorphous appearance of epicuticular waxes in conifers, usually called wax ‘degradation’ or ‘erosion’, which is often correlated with tree damage symptoms, e.g., winter desiccation. Previous investigations concentrated on wax chemistry, with little success. Here, we address the hypothesis that both ‘wax degradation’ and decreasing drought tolerance of trees may result from physical factors following the deposition of salt particles onto the needles. Pine seedlings were sprayed with dry aerosols or 50 mM solutions of different salts. The needles underwent humidity changes within an environmental scanning electron microscope, causing salt expansion on the surface and into the epistomatal chambers. The development of amorphous wax appearance by deliquescent salts covering tubular wax fibrils was demonstrated. The minimum epidermal conductance of the sprayed pine seedlings increased. Aerosol deposition potentially ‘degrades’ waxes and decreases tree drought tolerance. These effects have not been adequately considered thus far in air pollution research. Highlights: • Demonstrated capability of particles to produce ‘wax degradation’. • Dynamics of particles on pine needles, shown by videos. • Salt particles sprayed on pine needles increased minimum epidermal conductance g min . • Results strongly suggest direct link between air pollution and drought tolerance. • Linkage between different types of forest decline is suggested. -- ‘Wax degradation’ on pine needles and increased minimum epidermal conductance (i.e. uncontrollable water loss) were created by particles, suggesting a link between air pollution and tree drought tolerance

Evaluation of experimental data for wax and diamondoids solubility in gaseous systems

DEFF Research Database (Denmark)

Mohammadi, Amir H.; Gharagheizi, Farhad; Eslamimanesh, Ali

2012-01-01

The Leverage statistical approach is herein applied for evaluation of experimental data of the paraffin waxes/diamondoids solubility in gaseous systems. The calculation steps of this algorithm consist of determination of the statistical Hat matrix, sketching the Williams Plot, and calculation......-Santiago and Teja correlations are used to calculate/estimate the solubility of paraffin waxes (including n-C24H50 to n-C33H68) and diamondoids (adamantane and diamantane) in carbon dioxide/ethane gases, respectively. It can be interpreted from the obtained results that the applied equations for calculation...

Biochemical characterization and substrate specificity of jojoba fatty acyl-CoA reductase and jojoba wax synthase.

Science.gov (United States)

Miklaszewska, Magdalena; Banaś, Antoni

2016-08-01

Wax esters are used in industry for production of lubricants, pharmaceuticals and cosmetics. The only natural source of wax esters is jojoba oil. A much wider variety of industrial wax esters-containing oils can be generated through genetic engineering. Biotechnological production of tailor-made wax esters requires, however, a detailed substrate specificity of fatty acyl-CoA reductases (FAR) and wax synthases (WS), the two enzymes involved in wax esters synthesis. In this study we have successfully characterized the substrate specificity of jojoba FAR and jojoba WS. The genes encoding both enzymes were expressed heterologously in Saccharomyces cerevisiae and the activity of tested enzymes was confirmed by in vivo studies and in vitro assays using microsomal preparations from transgenic yeast. Jojoba FAR exhibited the highest in vitro activity toward 18:0-CoA followed by 20:1-CoA and 22:1-CoA. The activity toward other 11 tested acyl-CoAs was low or undetectable as with 18:2-CoA and 18:3-CoA. In assays characterizing jojoba WS combinations of 17 fatty alcohols with 14 acyl-CoAs were tested. The enzyme displayed the highest activity toward 14:0-CoA and 16:0-CoA in combination with C16-C20 alcohols as well as toward C18 acyl-CoAs in combination with C12-C16 alcohols. 20:1-CoA was efficiently utilized in combination with most of the tested alcohols. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Review of data on the dermal penetration of mineral oils and waxes used in cosmetic applications.

Science.gov (United States)

Petry, T; Bury, D; Fautz, R; Hauser, M; Huber, B; Markowetz, A; Mishra, S; Rettinger, K; Schuh, W; Teichert, T

2017-10-05

Mineral oils and waxes used in cosmetic products, also referred to as "personal care products" outside the European Union, are mixtures of predominantly saturated hydrocarbons consisting of straight-chain, branched and ring structures with carbon chain lengths greater than C16. They are used in skin and lip care cosmetic products due to their excellent skin tolerance as well as their high protecting and cleansing performance and broad viscosity options. Recently, concerns have been raised regarding potential adverse health effects of mineral oils and waxes from dermal application of cosmetics. In order to be able to assess the risk for the consumer the dermal penetration potential of these ingredients has to be evaluated. The scope and objective of this review are to identify and summarize publicly available literature on the dermal penetration of mineral oils and waxes as used in cosmetic products. For this purpose, a comprehensive literature search was conducted. A total of 13 in vivo (human, animal) and in vitro studies investigating the dermal penetration of mineral oils and waxes has been identified and analysed. The majority of the substances were dermally adsorbed to the stratum corneum and only a minor fraction reached deeper skin layers. Overall, there is no evidence from the various studies that mineral oils and waxes are percutaneously absorbed and become systemically available. Thus, given the absence of dermal uptake, mineral oils and waxes as used in cosmetic products do not present a risk to the health of the consumer. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Variations of Leaf Cuticular Waxes Among C3 and C4 Gramineae Herbs.

Science.gov (United States)

He, Yuji; Gao, Jianhua; Guo, Na; Guo, Yanjun

2016-11-01

Modern C4 plants are commonly distributed in hot and dry environments whereas C3 plants predominate in cool and shade areas. At the outmost of plant surface, the deposition and chemical composition of cuticular waxes vary under different environmental conditions. However, whether such variation of cuticular wax is related to the distribution of C3 and C4 under different environmental conditions is still not clear. In this study, leaves of six C3 Gramineae herbs distributed in spring, Roegneria kamoji, Polypogon fugax, Poa annua, Avena fatua, Alopecurus aequalis, and Oplismenus undulatifolius, and four C4 and one C3 Gramineae herbs distributed in summer, Digitaria sanguinalis, Eleusine indica, Setaria viridis, S. plicata, and O. undulatifolius, were sampled and analyzed for cuticular wax. Plates were the main epicuticular wax morphology in both C3 and C4 plants except S. plicata. The plates melted in C4 plants but not in C3 plants. The total cuticular wax amounts in C4 plants were significantly lower than those in C3 plants, except for O. undulatifolius. Primary alcohols were the most abundant compounds in C3 plants, whereas n-alkanes were relatively the most abundant compounds in C4 plants. C 29 was the most abundant n-alkane in C3 plants except for O. undulatifolius, whereas the most abundant n-alkane was C 31 or C 33 in C4 plants. The average chain length (ACL) of n-alkanes was higher in C4 than in C3 plants, whereas the ACL of n-alkanoic acids was higher in C3 than C4 plants. The cluster analysis based on the distribution of n-alkanes clearly distinguished C3 and C4 plants into two groups, except for O. undulatifolius which was grouped with C4 plants. These results suggest that the variations of cuticular waxes among C3 and C4 Gramineae herbs are related to the distribution of C3 and C4 plants under different environmental conditions. © 2016 Wiley-VHCA AG, Zurich, Switzerland.

Effects of ozone exposures on epicuticular wax of ponderosa pine needles

International Nuclear Information System (INIS)

Bytnerowicz, A.; Turunen, M.

1994-01-01

Two-year-old ponderosa pine (Pinus ponderosa L.) seedlings were exposed during the 1989 and 1990 growing seasons to ozone in open-top chambers placed in a forested location at Shirley Meadow, Greenhorn Mountain Range, Sierra Nevada. The ozone treatments were as follows: charcoal-filtered air (CF); charcoal-filtered air with addition of ambient concentrations of ozone (CF + O 3 ); and charcoal-filtered air with addition of doubled concentrations of ozone (CF + 2 x O 3 ). Ozone effects on ponderosa pine seedlings progressed and accumulated over two seasons of exposure. Throughout the first season, increased visible injury and accelerated senescence of the foliage were noted. Subsequently, during the second season of ozone exposure, various physiological and biochemical changes in the foliage took place. All these changes led to reduced growth and biomass of the seedlings. Epistomatal waxes of needles from the CA + 2 x O 3 treatment had an occluded appearance. This phenomenon may be caused by earlier phenological development of needles from the high-ozone treatments and disturbed development and synthesis of waxes. It may also be caused by chemical degradation of waxes by exposures to high ozone concentrations. (orig.)

Molecular and Biochemical Characterization of Cotton Epicuticular Wax in Defense Against Cotton Leaf Curl Disease.

Science.gov (United States)

Khan, Muhammad Azmat Ullah; Shahid, Ahmad Ali; Rao, Abdul Qayyum; Bajwa, Kamran Shehzad; Samiullah, Tahir Rehman; Muzaffar, Adnan; Nasir, Idrees Ahmad; Husnain, Tayyab

2015-12-01

Gossypium arboreumis resistant to Cotton leaf curl Burewala virus and its cognate Cotton leaf curl Multan beta satellite ( CLCuBuV and CLCuMB ). However, the G. arboreum wax deficient mutant (GaWM3) is susceptible to CLCuV . Therefore, epicuticular wax was characterized both quantitatively and qualitatively for its role as physical barrier against whitefly mediated viral transmission and co-related with the titer of each viral component (DNA-A, alphasatellite and betasatellite) in plants. The hypothesis was the CLCuV titer in cotton is dependent on the amount of wax laid down on plant surface and the wax composition. Analysis of the presence of viral genes, namely alphasatellite, betasatellite and DNA-A, via real-time PCR in cotton species indicated that these genes are detectable in G. hirsutum , G. harknessii and GaWM3, whereas no particle was detected in G. arboreum . Quantitative wax analysis revealed that G. arboreum contained 183 μg.cm -2 as compared to GaWM3 with only 95 μg.cm -2 . G. hirsutum and G. harknessii had 130 μg.cm -2 and 146 μg.cm -2 , respectively. The GCMS results depicted that Lanceol, cis was 45% in G. harknessii . Heptadecanoic acid was dominant in G. arboreum with 25.6%. GaWM3 had 18% 1,2,-Benenedicarboxylic acid. G. hirsutum contained 25% diisooctyl ester. The whitefly feeding assay with Nile Blue dye showed no color in whiteflies gut fed on G. arboreum . In contrast, color was observed in the rest of whiteflies. From results, it was concluded that reduced quantity as well as absence of (1) 3-trifluoroacetoxytetradecane, (2) 2-piperidinone,n-|4-bromo-n-butyl|, (3) 4-heptafluorobutyroxypentadecane, (4) Silane, trichlorodocosyl-, (5) 6- Octadecenoic acid, methyl ester, and (6) Heptadecanoicacid,16-methyl-,methyl ester in wax could make plants susceptible to CLCuV , infested by whiteflies.

The effects of surgicel and bone wax hemostatic agents on bone healing: An experimental study

Directory of Open Access Journals (Sweden)

Nasser Nooh

2014-01-01

Full Text Available Background: The biological effects of hemostatic agends on the physiological healing process need to be tested. The aim of this study was to assess the effects of oxidized cellulose (surgicel and bone wax on bone healing in goats′ feet. Materials and Methods: Three congruent circular bone defects were created on the lateral aspects of the right and left metacarpal bones of ten goats. One defect was left unfilled and acted as a control; the remaining two defects were filled with bone wax and surgicel respectively. The 10 animals were divided into two groups of 5 animals each, to be sacrificed at the 3rd and 5th week postoperatively. Histological analysis assessing quality of bone formed and micro-computed tomography (MCT measuring the quantities of bone volume (BV and bone density (BD were performed. The results of MCT analysis pertaining to BV and BD were statistically analyzed using two-way analysis of variance (ANOVA and posthoc least significant difference tests. Results: Histological analysis at 3 weeks showed granulation tissue with new bone formation in the control defects, active bone formation only at the borders for surgicel filled defects and fibrous encapsulation with foreign body reaction in the bone wax filled defects. At 5 weeks, the control and surgicel filled defects showed greater bone formation; however the control defects had the greatest amount of new bone. Bone wax filled defects showed very little bone formation. The two-way ANOVA for MCT results showed significant differences for BV and BD between the different hemostatic agents during the two examination periods. Conclusion: Surgicel has superiority over bone wax in terms of osseous healing. Bone wax significantly hinders osteogenesis and induces inflammation.

Rapid atmospheric transport and large-scale deposition of recently synthesized plant waxes

Science.gov (United States)

Nelson, Daniel B.; Ladd, S. Nemiah; Schubert, Carsten J.; Kahmen, Ansgar

2018-02-01

Sedimentary plant wax 2H/1H ratios are important tools for understanding hydroclimate and environmental changes, but large spatial and temporal uncertainties exist about transport mechanisms from ecosystem to sediments. To assess atmospheric pathways, we collected aerosol samples for two years at four locations within a ∼60 km radius in northern Switzerland. We measured n-alkane distributions and 2H/1H ratios in these samples, and from local plants, leaf litter, and soil, as well as surface sediment from six nearby lakes. Increased concentrations and 2H depletion of long odd chain n-alkanes in early summer aerosols indicate that most wax aerosol production occurred shortly after leaf unfolding, when plants synthesize waxes in large quantities. During autumn and winter, aerosols were characterized by degraded n-alkanes lacking chain length preferences diagnostic of recent biosynthesis, and 2H/1H values that were in some cases more than 100‰ higher than growing season values. Despite these seasonal shifts, modeled deposition-weighted average 2H/1H values of long odd chain n-alkanes primarily reflected summer values. This was corroborated by n-alkane 2H/1H values in lake sediments, which were similar to deposition-weighted aerosol values at five of six sites. Atmospheric deposition rates for plant n-alkanes on land were ∼20% of accumulation rates in lakes, suggesting a role for direct deposition to lakes or coastal oceans near similar production sources, and likely a larger role for deposition on land and transport in river systems. This mechanism allows mobilization and transport of large quantities of recently produced waxes as fine-grained material to low energy sedimentation sites over short timescales, even in areas with limited topography. Widespread atmospheric transfer well before leaf senescence also highlights the importance of the isotopic composition of early season source water used to synthesize waxes for the geologic record.

Thermal characterizations of the paraffin wax/low density polyethylene blends as a solid fuel

Energy Technology Data Exchange (ETDEWEB)

Kim, Soojong; Moon, Heejang; Kim, Jinkon, E-mail: jkkim@kau.ac.kr

2015-08-10

Highlights: • Regression rate of blends fuel is higher than polymer fuel. • LDPE is an effective mixing ingredient for the combustion efficiency. • Blends fuel is a uniform mixture with two degradation steps. • LDPE plays a positive role for the low sensitivity to the thermal deformation • Blends with low LDPE content can be an effective fuel for hybrid rocket application. - Abstract: Thermal characterizations of a novel solid fuel for hybrid rocket application, based on the paraffin wax blends with low density polyethylene (LDPE) concentration of 5% (SF-5) and 10% (SF-10) were conducted. Both the increased regression rate in comparison with the polymeric fuel, and the improved combustion efficiency in comparison with the pure paraffin fuel reveal that the blend fuels achieve higher combustion performance. The morphology of the shape stabilized paraffin wax/LDPE blends was characterized by the scanning electron microscopy (SEM). Although the SEM observation indicated the blends have uniform mixtures, they showed two degradation steps confirming the immiscibility of components in the crystalline phase from thermogravimetric analysis (TGA). The differential scanning calorimeter (DSC) results showed that the melting temperature of LDPE in the blends decreased with an increase of paraffin wax content. The decreasing total specific melting enthalpy of blended fuels with decreasing paraffin wax content is in fairly good agreement with the additive rule. In thermomechanical analysis (TMA), the linear coefficient of thermal expansion (LCTE) seems to decrease with an increase of LDPE loading, however, the loaded LDPE do merely affect the LCTE in case of the blends with low LDPE concentration. It was found that a blend of low concentration of LDPE with a relatively high concentration of paraffin wax can lead to a potential novel fuel for rocket application, a contrary case with respect to the field of phase change materials (PCM) where a blend of high concentration

Thermal characterizations of the paraffin wax/low density polyethylene blends as a solid fuel

International Nuclear Information System (INIS)

Kim, Soojong; Moon, Heejang; Kim, Jinkon

2015-01-01

Highlights: • Regression rate of blends fuel is higher than polymer fuel. • LDPE is an effective mixing ingredient for the combustion efficiency. • Blends fuel is a uniform mixture with two degradation steps. • LDPE plays a positive role for the low sensitivity to the thermal deformation • Blends with low LDPE content can be an effective fuel for hybrid rocket application. - Abstract: Thermal characterizations of a novel solid fuel for hybrid rocket application, based on the paraffin wax blends with low density polyethylene (LDPE) concentration of 5% (SF-5) and 10% (SF-10) were conducted. Both the increased regression rate in comparison with the polymeric fuel, and the improved combustion efficiency in comparison with the pure paraffin fuel reveal that the blend fuels achieve higher combustion performance. The morphology of the shape stabilized paraffin wax/LDPE blends was characterized by the scanning electron microscopy (SEM). Although the SEM observation indicated the blends have uniform mixtures, they showed two degradation steps confirming the immiscibility of components in the crystalline phase from thermogravimetric analysis (TGA). The differential scanning calorimeter (DSC) results showed that the melting temperature of LDPE in the blends decreased with an increase of paraffin wax content. The decreasing total specific melting enthalpy of blended fuels with decreasing paraffin wax content is in fairly good agreement with the additive rule. In thermomechanical analysis (TMA), the linear coefficient of thermal expansion (LCTE) seems to decrease with an increase of LDPE loading, however, the loaded LDPE do merely affect the LCTE in case of the blends with low LDPE concentration. It was found that a blend of low concentration of LDPE with a relatively high concentration of paraffin wax can lead to a potential novel fuel for rocket application, a contrary case with respect to the field of phase change materials (PCM) where a blend of high concentration

The Preparation and Performances of Self-Dispersed Nanomicron Emulsified Wax Solid Lubricant Ewax for Drilling Fluids

Directory of Open Access Journals (Sweden)

Feng-shan Zhou

2014-01-01

Full Text Available An oil-in-water nanomicron wax emulsion with oil phase content 45 wt% was prepared by using the emulsifying method of surfactant-in-oil. The optimum prepared condition is 85°C, 20 min, and 5 wt% complex emulsifiers. Then the abovementioned nanomicron emulsifying wax was immersed into a special water-soluble polymer in a certain percentage by the semidry technology. At last, a solidified self-dispersed nanomicron emulsified wax named as Ewax, a kind of solid lubricant for water based drilling fluid, was obtained after dried in the special soluble polymer containing emulsifying wax in low temperature. It is shown that the adhesion coefficient reduced rate (ΔKf is 73.5% and the extreme pressure (E-P friction coefficient reduced rate (Δf is 77.6% when the produced Ewax sample was added to fresh water based drilling fluid at dosage 1.0 wt%. In comparison with other normal similar liquid products, Ewax not only has better performances of lubrication, filtration loss control property, heat resistance, and tolerance to salt and is environmentally friendly, but also can solve the problems of freezing in the winter and poor storage stability of liquid wax emulsion in oilfield applications.

Dental Caries and Related Factors among 7-12 Year-old School Children in Yasuj, Iran, in 2014

Directory of Open Access Journals (Sweden)

M Yousofi

2015-12-01

Full Text Available Introduction and objective: Tooth caries is the most prevalent infectious disease in children. The purpose of this study was to assess carries experience indexes and related factors among 7-12 year-old school children in Yasuj, Iran, in 2014. Materials and methods: In the present Cross-sectional and analytical study, using a two-stage random sampling, 460 students from primary schools of Yasuj city and surrounding villages were selected. The children were clinically examined at their school by a professional calibrated dentistry team. Their demographic and socioeconomic status, mouth health behaviors and teeth carries status and consumed nutritional materials were gathered by a questioner and a dental chart. The data were analyzed using inferential statistical methods. The SPSS software version 22 was used to extract the outputs and &alpha=0.05 was considered as the significant level. Results: The dental caries prevalence of deciduous, permanent and total of  two type of dents were  75.2, 41.1 and  89.8 percent, respectively and the dmft, DMFT and dmft+DMFT indexes were 3.57, 0.87, and 4.44, respectively.. The caries prevalence of permanent teeth and DMFT in girls were significantly higher than boys (p=0.046, but the caries prevalence in total of dents in boys was significantly higher than girls ( p=0.32. Furthermore, the dental caries prevalence in permanent teeth and DMFT in children resident in rural areas were significantly higher than those in urban areas (p0.1.  Conclusions: Prevalence and severity score of dental caries among 7 - 12 year-old Yasuj students were higher than the WHO standards. The tooth caries experiences were more prevalent in boys and in children resident in rural areas, increased with age and decreased with BMI and less prevalent in children with higher family socioeconomic status. Tooth brushing and flossing and consuming dairy foods were protective agents in occurring tooth caries in primary school children in

Neutral Lipid Biosynthesis in Engineered Escherichia coli: Jojoba Oil-Like Wax Esters and Fatty Acid Butyl Esters

OpenAIRE

Kalscheuer, Rainer; Stöveken, Tim; Luftmann, Heinrich; Malkus, Ursula; Reichelt, Rudolf; Steinbüchel, Alexander

2006-01-01

Wax esters are esters of long-chain fatty acids and long-chain fatty alcohols which are of considerable commercial importance and are produced on a scale of 3 million tons per year. The oil from the jojoba plant (Simmondsia chinensis) is the main biological source of wax esters. Although it has a multitude of potential applications, the use of jojoba oil is restricted, due to its high price. In this study, we describe the establishment of heterologous wax ester biosynthesis in a recombinant E...

Design and evaluation of a heat exchanger that uses paraffin wax and recycled materials as solar energy accumulator

International Nuclear Information System (INIS)

Reyes, Alejandro; Negrete, Daniela; Mahn, Andrea; Sepúlveda, Francisco

2014-01-01

Highlights: • Thermal conductivity of paraffin wax was improved with aluminum wool. • Aluminum wool surrounding the cans favored the energy recuperation from the wax. • The heat exchanger accumulated 3000 kJ energy. • The accumulated energy can be easily increased with larger units. • COMSOL simulated adequately the energy removal process from the cans. - Abstract: Soft drink cans filled with paraffin wax mixed with 5% w/w aluminum wool, obtained from disposable cans, doubled the thermal conductivity of cans filled only with paraffin wax. Thermal conductivity of the systems was determined by two ways: directly using a thermal conductivimeter, and indirectly based on temperature profiles and on the analytical solution of a cylinder. We designed, built and evaluated a heat exchanger for solar energy accumulation, composed by 48 disposable soft drink cans filled with a total of 9.5 kg of paraffin wax mixed with 5% w/w aluminum wool. In sunny days, the wax melted completely in 3 h. The accumulated energy of 3000 kJ, allowed increasing the temperature of 3.5 m 3 /h air flow rate from 20 to 40 °C during a period of 2 h. This application will allow extending the use of solar energy in drying processes or could be used as household calefaction system. The progress of the phase change front in time during the energy discharge period was simulated with COMSOL, whereas the effect of the number of cans and thermal conductivity of the paraffin wax on the air temperature increase was simulated with MATLAB

New hybrid nanofluid containing encapsulated paraffin wax and sand nanoparticles in propylene glycol-water mixture: Potential heat transfer fluid for energy management

International Nuclear Information System (INIS)

Manikandan, S.; Rajan, K.S.

2017-01-01

Highlights: • Hybrid nanofluid containing sand nanoparticles & encapsulated paraffin wax prepared. • Specific heat of hybrid nanofluid 9% greater than that of PG-water mixture. • Specific heat & thermal conductivity enhanced at optimum paraffin wax concentration. • Hybrid nanofluid with 1 wt.% paraffin wax & 1 vol% sand nanoparticles best suited. - Abstract: The reduction in specific heat commonly encountered due to the addition of nanoparticles to a heat transfer fluid such as propylene glycol-water mixture, can be overcome by co-dispersing surfactant-encapsulated paraffin wax, leading to formation of a hybrid nanofluid. Experimental investigations have been carried out on the preparation and evaluation of thermophysical properties of a hybrid nanofluid containing pluronic P-123 encapsulated paraffin wax (70–120 nm diameter, 1–5 wt.%) and sand nanoparticles (1 vol%) in propylene glycol-water mixture. The comparison of results of differential scanning calorimetry of pure paraffin wax and encapsulated paraffin wax revealed encapsulation efficiency of 84.4%. The specific heat of hybrid nanofluids monotonously increased with paraffin wax concentration, with 9.1% enhancement in specific heat for hybrid nanofluid containing 5 wt.% paraffin wax, in comparison to propylene glycol-water mixture. There exists an optimum paraffin wax concentration (1 wt.%) for the hybrid nanofluid at which the combination of various thermophysical properties such as specific heat, thermal conductivity and viscosity are favorable for use as heat transfer fluid. Such a hybrid nanofluid can be used as a substitute for propylene glycol-water mixture in solar thermal systems.

In search of low cost biological analysis: Wax or acrylic glue bonded paper microfluidic devices

KAUST Repository

Kodzius, Rimantas; Gong, Xiuqing; Li, Shunbo; Qin, Jianhua; Wen, Weijia; Wu, Jinbo; Xiao, Kang; Yi, Xin

2011-01-01

We report a simple, low-cost and detachable microfluidic chip incorporating easily accessible paper, glass slides or other polymer films as the chip materials along with adhesive wax or cyanoacrylate-based resin as the recycling bonding material. We use a laser to cut through the paper or film to form patterns and then sandwich the paper and film between glass sheets or polymer membranes. The hot-melt adhesive wax or simple cyanoacrylate-based resin can realize bridge bonding between various materials, for example, paper, polymethylmethacrylate film, glass sheets, or metal plate. The wax bonding process is reversible and the wax is reusable through a melting and cooling process. With this process, a three-dimensional (3D) microfluidic chip is achievable by evacuating the channels of adhesive material in a hot-water. We applied the wax-paper based microfluidic chip to HeLa cell electroporation. Subsequently, a prototype of a 5-layer 3D chip was fabricated by multilayer wax bonding. To check the sealing ability and the durability of the chip, green fluorescence protein recombinant E. coli bacteria were cultured, with which the chemotaxis of E. coli was studied in order to determine the influence of antibiotic ciprofloxacin concentration on the E. coli migration. The chip bonded with cyanoacrylate-based resin was tested by measuring protein concentration and carrying out DNA capillary electrophoresis. To study the biocompatibility and applicability of our microfluidic chip fabrication technology, we tested the PCR compatibility of our chip materials along with various other common materials employed in the fabrication of microfluidic chips including: silicon, several kinds of silicon oxide, glasses, plastics, wax, and adhesives, etc. Two-temperature PCR was performed with these materials to determine their PCR-inhibitory effect. In most of the cases, addition of bovine serum albumin effectively improved the reaction yield. We also studied the individual PCR components

Thermodynamics Prediction of Wax Precipitation in Black Oil Using Regular Solution Model and Plus Fraction Characterization

Directory of Open Access Journals (Sweden)

Wei Wang

2013-01-01

Full Text Available The precipitation of wax/solid paraffin during production, transportation, and processing of crude oil is a serious problem. It is essential to have a reliable model to predict the wax appearance temperature and the amount of solid precipitated at different conditions. This paper presents a work to predict the solid precipitation based on solid-liquid equilibrium with regular solution-molecular thermodynamic theory and characterization of the crude oil plus fraction. Due to the differences of solubility characteristics between solid and liquid phase, the solubility parameters of liquid and solid phase are calculated by a modified model. The heat capacity change between solid and liquid phase is considered and estimated in the thermodynamic model. An activity coefficient based thermodynamic method combined with two characteristic methods to calculate wax precipitation in crude oil, especially heavy oil, has been tested with experimental data. The results show that the wax appearance temperature and the amount of weight precipitated can be predicted well with the experimental data.

The moss Funaria hygrometrica has cuticular wax similar to vascular plants, with distinct composition on leafy gametophyte, calyptra and sporophyte capsule surfaces.

Science.gov (United States)

Busta, Lucas; Budke, Jessica M; Jetter, Reinhard

2016-09-01

Aerial surfaces of land plants are covered with a waxy cuticle to protect against water loss. The amount and composition of cuticular waxes on moss surfaces had rarely been investigated. Accordingly, the degree of similarity between moss and vascular plant waxes, and between maternal and offspring moss structure waxes is unknown. To resolve these issues, this study aimed at providing a comprehensive analysis of the waxes on the leafy gametophyte, gametophyte calyptra and sporophyte capsule of the moss Funaria hygrometrica Waxes were extracted from the surfaces of leafy gametophytes, gametophyte calyptrae and sporophyte capsules, separated by gas chromatography, identified qualitatively with mass spectrometry, and quantified with flame ionization detection. Diagnostic mass spectral peaks were used to determine the isomer composition of wax esters. The surfaces of the leafy gametophyte, calyptra and sporophyte capsule of F. hygrometrica were covered with 0·94, 2·0 and 0·44 μg cm(-2) wax, respectively. While each wax mixture was composed of mainly fatty acid alkyl esters, the waxes from maternal and offspring structures had unique compositional markers. β-Hydroxy fatty acid alkyl esters were limited to the leafy gametophyte and calyptra, while alkanes, aldehydes and diol esters were restricted to the sporophyte capsule. Ubiquitous fatty acids, alcohols, fatty acid alkyl esters, aldehydes and alkanes were all found on at least one surface. This is the first study to determine wax coverage (μg cm(-2)) on a moss surface, enabling direct comparisons with vascular plants, which were shown to have an equal amount or more wax than F. hygrometrica Wax ester biosynthesis is of particular importance in this species, and the ester-forming enzyme(s) in different parts of the moss may have different substrate preferences. Furthermore, the alkane-forming wax biosynthesis pathway, found widely in vascular plants, is active in the sporophyte capsule, but not in the leafy

In search of low cost biological analysis: Wax or acrylic glue bonded paper microfluidic devices

KAUST Repository

Kodzius, Rimantas

2011-01-22

In this body of work we have been developing and characterizing paper based microfluidic fabrication technologies to produce low cost biological analysis. Specifically we investigated the performance of paper microfluidics that had been bonded using wax or acrylic glue, and characterized the affect of these and other microfluidic materials on the polymerase chain reaction (PCR). We report a simple, low-cost and detachable microfluidic chip incorporating easily accessible paper, glass slides or other polymer films as the chip materials along with adhesive wax or cyanoacrylate-based resin as the recycling bonding material. We use a laser to cut through the paper or film to form patterns and then sandwich the paper and film between glass sheets or polymer membranes. The hot-melt adhesive wax or simple cyanoacrylate-based resin can realize bridge bonding between various materials, for example, paper, polymethylmethacrylate film, glass sheets, or metal plate. The wax bonding process is reversible and the wax is reusable through a melting and cooling process. With this process, a three-dimensional (3D) microfluidic chip is achievable by evacuating the channels of adhesive material in a hot-water. We applied the wax-paper based microfluidic chip to HeLa cell electroporation. Subsequently, a prototype of a 5-layer 3D chip was fabricated by multilayer wax bonding. To check the sealing ability and the durability of the chip, green fluorescence protein recombinant E. coli bacteria were cultured, with which the chemotaxis of E. coli was studied in order to determine the influence of antibiotic ciprofloxacin concentration on the E. coli migration. The chip bonded with cyanoacrylate-based resin was tested by measuring protein concentration and carrying out DNA capillary electrophoresis. To study the biocompatibility and applicability of our microfluidic chip fabrication technology, we tested the PCR compatibility of our chip materials along with various other common materials

Molecular analysis of intact preen waxes of Calidris canutus (Aves : Scolopacidae) by gas chromatography/mass spectrometry

NARCIS (Netherlands)

Dekker, MHA; Piersma, T; Damste, JSS; Dekker, Marlèn H.A.; Sinninghe Damsté, Jaap S.

The intact preen wax esters of the red knot Calidris canutus were studied with gas chromatography/mass spectrometry (GC/MS) and GC/MS/MS. In this latter technique, transitions from the molecular ion to fragment ions representing the fatty acid moiety of the wax esters were measured, providing

A new experimental method to prevent paraffin - wax formation on the crude oil wells: A field case study in Libya

Directory of Open Access Journals (Sweden)

Elhaddad Elnori E.

2015-01-01

Full Text Available Wax formation and deposition is one of the most common problems in oil producing wells. This problem occurs as a result of the reduction of the produced fluid temperature below the wax appearance temperature (range between 46°C and 50°C and the pour point temperature (range between 42°C and 44°C. In this study, two new methods for preventing wax formation were implemented on three oil wells in Libya, where the surface temperature is, normally, 29°C. In the first method, the gas was injected at a pressure of 83.3 bar and a temperature of 65°C (greater than the pour point temperature during the gas-lift operation. In the second method, wax inhibitors (Trichloroethylene-xylene (TEX, Ethylene copolymers, and Comb polymers were injected down the casings together with the gas. Field observations confirmed that by applying these techniques, the production string was kept clean and no wax was formed. The obtained results show that the wax formation could be prevented by both methods.

Effect of gamma radiation and entomopathogenic nematodes on greater wax moth, Galleria mellonella (Linnaeus) [Lep., Pyralidae

International Nuclear Information System (INIS)

Ali, R.M.S.

2008-01-01

The greater wax moth, Galleria mellonella (L.), is a lepidoptera insect; its larval stage, feeds on wax and pollen stored in combs of active honey bee colonies (Milam, 1970). It does not attack adult bees but destructs combs of a weak colony by chewing the comb; spinning silk-lined tunnels through the cell wall and over the face of the comb, which prevent the bees to emerge by their abdomen from their cell, so they die by starvation as they unable to escape from their cell. They also eat out a place to spin their cocoons in the soft wood of the bee hive. Galleria mellonella can also destroy stored honey combs. Therefore, it is considered a major pest of the honeybee. Damage will vary with the level of infestation and the time that has elapsed since the infestation first began. In time, stored combs may be completely destroyed and the frames and combs become filled with a mass of tough, silky web. In ideal conditions for wax moth development, a box (super) of combs may be rendered useless in about a week. Damage occurs mainly in the warm and hot months of the year when wax moths are most active. However, considerable damage can still occur during the cool part of late autumn and early spring as greater wax moth can produce a large amount of metabolic heat which can raise the immediate temperature around them by up to 25 degree C above the normal environment temperature. At the time of storage, combs that are apparently free of wax moth may contain eggs that will hatch later. They should be monitored

Preparing paraffin wax, etc

Energy Technology Data Exchange (ETDEWEB)

1935-12-27

A process is described for preparing paraffin wax by separation from substances containing bitumen, consisting of treating the raw material at an elevated temperature under such moderate conditions and by means of such organic solvents that the bitumen present in the raw material or formed in the process dissolves as well as the asphaltic and phenolic substances and the humic acids which may be said to be neither extracts nor decomposed materials, and then submitting the products and extracts to a treatment with hydrogen gas, which is effected below 300/sup 0/C, and passing the material over fixed hydrogenation catalysts above 300/sup 0/C by means of hydrogenation catalysts finely dispersed in carbonaceous materials all avoiding decomposition with the formation of volatile products.

The effects of magnetic fields on carnauba wax electret formation

Science.gov (United States)

Clator, Irvin G.

1987-08-01

The results of thermally stimulated depolarization current and effective surface charge-density measurements indicate that magnetic fields do not produce carnauba wax electrets and that previously reported data can be attributed to nonmagnetic effects.

Education About Dental Hygienists' Roles in Public Dental Prevention Programs: Dental and Dental Hygiene Students' and Faculty Members' and Dental Hygienists' Perspectives.

Science.gov (United States)

Pervez, Anushey; Kinney, Janet S; Gwozdek, Anne; Farrell, Christine M; Inglehart, Marita R

2016-09-01

In 2005, Public Act No. 161 (PA 161) was passed in Michigan, allowing dental hygienists to practice in approved public dental prevention programs to provide services for underserved populations while utilizing a collaborative agreement with a supervising dentist. The aims of this study were to assess how well dental and dental hygiene students and faculty members and practicing dental hygienists have been educated about PA 161, what attitudes and knowledge about the act they have, and how interested they are in additional education about it. University of Michigan dental and dental hygiene students and faculty members, students in other Michigan dental hygiene programs, and dental hygienists in the state were surveyed. Respondents (response rate) were 160 dental students (50%), 63 dental hygiene students (82%), 30 dental faculty members (26%), and 12 dental hygiene faculty members (52%) at the University of Michigan; 143 dental hygiene students in other programs (20%); and 95 members of the Michigan Dental Hygienists' Association (10%). The results showed that the dental students were less educated about PA 161 than the dental hygiene students, and the dental faculty members were less informed than the dental hygiene faculty members and dental hygienists. Responding dental hygiene faculty members and dental hygienists had more positive attitudes about PA 161 than did the students and dental faculty members. Most of the dental hygiene faculty members and dental hygienists knew a person providing services in a PA 161 program. Most dental hygiene students, faculty members, and dental hygienists wanted more education about PA 161. Overall, the better educated about the program the respondents were, the more positive their attitudes, and the more interested they were in learning more.

Synchrotron WAXS and XANES studies of silica (SiO2) powders synthesized from Indonesian natural sands

International Nuclear Information System (INIS)

Muchlis, Khairanissa; Fauziyah, Nur Aini; Pratapa, Suminar; Soontaranon, Siriwat; Limpirat, Wanwisa

2017-01-01

In this study, we have investigated polymorphic silica (SiO 2 ) powders using, Wide Angle X-ray Scattering (WAXS) and X-Ray Absorption Near Edge Spectroscopy (XANES), laboratory X-Ray Diffraction (XRD) instruments. The WAXS and XANES spectra were collected using synchrotron radiation at Synchrotron Light Research Institute (SLRI), Nakhon Ratchasima, Thailand. The silica powders were obtained by processing silica sand from Tanah Laut, South Kalimantan, Indonesia. Purification process of silica sand was done by magnetic separation and immersion with HCl. The purification step was needed to reduce impurity or undesirable non Si elements. Three polymorphs of silica were produced, i.e. amorphous phase (A), quartz (B), and cristobalite (C). WAXS profile for each phase was presented in terms of intensity vs. 2θ prior to analyses. Both XRD (λ CuKα =1.54056 Å) and WAXS (λ=1.09 Å) patttern show that (1) A sample contains no crystallites, (2) B sample is monophasic, contains only quartz, and (3) C sample contains cristobalite and trydimite. XRD quantitative analysis using Rietica gave 98,8 wt% cristobalite, while the associated WAXS data provided 98.7 wt% cristobalite. Si K-edge XANES spectra were measured at energy range 1840 to 1920 eV. Qualitatively, the pre-edge and edge features for all phases are similar, but their main peaks in the post-edge region are different. (paper)

Heat transfer enhancement in energy storage in spherical capsules filled with paraffin wax and metal beads

International Nuclear Information System (INIS)

Ettouney, Hisham; Alatiqi, Imad; Al-Sahali, Mohammad; Al-Hajirie, Khalida

2006-01-01

Energy storage is an attractive option to conserve limited energy resources, where more than 50% of the generated industrial energy is discarded in cooling water and stack gases. This study focuses on the evaluation of heat transfer enhancement in phase change energy storage units. The experiments are performed using spherical capsules filled with paraffin wax and metal beads. The experiments are conducted by inserting a single spherical capsule filled with wax and metal beads in a stream of hot/cold air. Experimental measurements include the temperature field within the spherical capsule and in the air stream. To determine the enhancement effects of the metal beads, the measured data is correlated against those for a spherical capsule filled with pure wax. Data analysis shows a reduction of 15% in the melting and solidification times upon increasing the number and diameter of the metal beads. This reduction is caused by a similar decrease in the thermal load of the sphere due to replacement of the wax by metal beads. The small size of the spherical capsule limits the enhancement effects; this is evident upon comparison of the heat transfer in a larger size, double pipe energy storage unit, where 2% of the wax volume is replaced with metal inserts, result in a three fold reduction in the melting/solidification time and a similar enhancement in the heat transfer rate

Ex vivo imaging of early dental caries within the interproximal space

Science.gov (United States)

Choo-Smith, Lin-P'ing; Hewko, Mark D.; Dufour, Marc L.; Fulton, Crystal; Qiu, Pingli; Gauthier, Bruno; Padioleau, Christian; Bisaillon, Charles-Etienne; Dong, Cecilia; Cleghorn, Blaine M.; Lamouche, Guy; Sowa, Michael G.

2009-02-01

Optical coherence tomography (OCT) is emerging as a technology that can potentially be used for the detection and monitoring of early dental enamel caries since it can provide high-resolution depth imaging of early lesions. To date, most caries detection optical technologies are well suited for examining caries at facial, lingual, incisal and occlusal surfaces. The approximal surfaces between adjacent teeth are difficult to examine due to lack of visual access and limited space for these new caries detection tools. Using a catheter-style probe developed at the NRC-Industrial Materials Institute, the probe was inserted into the interproximal space to examine the approximal surfaces with OCT imaging at 1310 nm. The probe was rotated continuously and translated axially to generate depth images in a spiral fashion. The probe was used in a mock tooth arch model consisting of extracted human teeth mounted with dental rope wax in their anatomically correct positions. With this ex vivo model, the probe provided images of the approximal surfaces revealing morphological structural details, regions of calculus, and especially regions of early dental caries (white spot lesions). Results were compared with those obtained from OCT imaging of individual samples where the approximal surfaces of extracted teeth are accessible on a lab-bench. Issues regarding access, regions of interest, and factors to be considered in an in vivo setting will be discussed. Future studies are aimed at using the probe in vivo with patient volunteers.

Neutral lipid biosynthesis in engineered Escherichia coli: jojoba oil-like wax esters and fatty acid butyl esters.

Science.gov (United States)

Kalscheuer, Rainer; Stöveken, Tim; Luftmann, Heinrich; Malkus, Ursula; Reichelt, Rudolf; Steinbüchel, Alexander

2006-02-01

Wax esters are esters of long-chain fatty acids and long-chain fatty alcohols which are of considerable commercial importance and are produced on a scale of 3 million tons per year. The oil from the jojoba plant (Simmondsia chinensis) is the main biological source of wax esters. Although it has a multitude of potential applications, the use of jojoba oil is restricted, due to its high price. In this study, we describe the establishment of heterologous wax ester biosynthesis in a recombinant Escherichia coli strain by coexpression of a fatty alcohol-producing bifunctional acyl-coenzyme A reductase from the jojoba plant and a bacterial wax ester synthase from Acinetobacter baylyi strain ADP1, catalyzing the esterification of fatty alcohols and coenzyme A thioesters of fatty acids. In the presence of oleate, jojoba oil-like wax esters such as palmityl oleate, palmityl palmitoleate, and oleyl oleate were produced, amounting to up to ca. 1% of the cellular dry weight. In addition to wax esters, fatty acid butyl esters were unexpectedly observed in the presence of oleate. The latter could be attributed to solvent residues of 1-butanol present in the medium component, Bacto tryptone. Neutral lipids produced in recombinant E. coli were accumulated as intracytoplasmic inclusions, demonstrating that the formation and structural integrity of bacterial lipid bodies do not require specific structural proteins. This is the first report on substantial biosynthesis and accumulation of neutral lipids in E. coli, which might open new perspectives for the biotechnological production of cheap jojoba oil equivalents from inexpensive resources employing recombinant microorganisms.

X-ray scattering evaluation of ultrastructural changes in human dental tissues with thermal treatment.

Science.gov (United States)

Sandholzer, Michael A; Sui, Tan; Korsunsky, Alexander M; Walmsley, Anthony Damien; Lumley, Philip J; Landini, Gabriel

2014-05-01

Micro- and ultrastructural analysis of burned skeletal remains is crucial for obtaining a reliable estimation of cremation temperature. Earlier studies mainly focused on heat-induced changes in bone tissue, while this study extends this research to human dental tissues using a novel quantitative analytical approach. Twelve tooth sections were burned at 400-900°C (30-min exposure, increments of 100°C). Subsequent combined small- and wide-angle X-ray scattering (SAXS/WAXS) experiments were performed at the Diamond Light Source synchrotron facility, where 28 scattering patterns were collected within each tooth section. In comparison with the control sample, an increase in mean crystal thickness was found in burned dentine (2.8-fold) and enamel (1.4-fold), however at a smaller rate than reported earlier for bone tissue (5-10.7-fold). The results provide a structural reference for traditional X-ray scattering methods and emphasize the need to investigate bone and dental tissues separately to obtain a reliable estimation of cremation temperature. © 2014 American Academy of Forensic Sciences.

Effect of emulsifier type and concentration, aqueous phase volume and wax ratio on physical, material and mechanical properties of water in oil lipsticks.

Science.gov (United States)

Beri, A; Norton, J E; Norton, I T

2013-12-01

Water-in-oil emulsions in lipsticks could have the potential to improve moisturizing properties and deliver hydrophilic molecules to the lips. The aims of this work were (i) to investigate the effect of emulsifier type (polymer vs. monomer, and saturated vs. unsaturated chain) and concentration on droplet size and (ii) to investigate the effect of wax ratio (carnauba wax, microcrystalline wax, paraffin wax and performalene) and aqueous phase volume on material properties (Young's modulus, point of fracture, elastic modulus and viscous modulus). Emulsion formation was achieved using a high shear mixer. Results showed that the saturated nature of the emulsifier had very little effect on droplet size, neither did the use of an emulsifier with a larger head group (droplet size ~18-25 μm). Polyglycerol polyricinoleate (PGPR) resulted in emulsions with the smallest droplets (~3-5 μm), as expected from previous studies that show that it produces a thick elastic interface. The results also showed that both Young's modulus and point of fracture increase with increasing percentage of carnauba wax (following a power law dependency of 3), but decrease with increasing percentage of microcrystalline wax, suggesting that the carnauba wax is included in the overall wax network formed by the saturated components, whereas the microcrystalline wax forms irregular crystals that disrupt the overall wax crystal network. Young's modulus, elastic modulus and viscous modulus all decrease with increasing aqueous phase volume in the emulsions, although the slope of the decrease in elastic and viscous moduli is dependent on the addition of solid wax, as a result of strengthening the network. This work suggests the potential use for emulsions in lipstick applications, particularly when PGPR is used as an emulsifier, and with the addition of solid wax, as it increases network strength. © 2013 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Enhanced ethanol production by removal of cutin and epicuticular waxes of wheat straw by plasma assisted pretreatment

DEFF Research Database (Denmark)

Kádár, Zsófia; Schultz-Jensen, Nadja; Jensen, J. S.

2015-01-01

as with Scanning Electron Microscopy (SEM) imaging. Compounds resulting from wax degradation were analyzed in the washing water of PAP wheat straw. The wax removal enhanced enzymatic hydrolysis yield and, consequently, the efficiency of wheat straw conversion into ethanol. In total, PAP increased the conversion...

Thermal Cracking to Improve the Qualification of the Waxes

Science.gov (United States)

He, B.; Agblevor, F. A.; Chen, C. G.; Feng, J.

2018-05-01

Thermal cracking of waxes at mild conditions (430-500°C) has been reconsidered as a possible refining technology for the production of fuels and chemicals. In this study, the more moderate thermal cracking was investigated to process Uinta Basin soft waxes to achieve the required pour point so that they can be pumped to the refineries. The best thermal cracking conditions were set 420°C and 20 minutes. The viscosity and density of the final liquid product were respectively achieved as 2.63 mP•s and 0.784 g/cm3 at 40°C. The result of FT-IR analysis of the liquid product indicated that the unsaturated hydrocarbons were produced after thermal cracking, which was corroborated by the 13C NMR spectrum. The GC analysis of the final gas product indicated that the hydrogen was produced; the dehydrogenation reaction was also proved by the elemental analysis and HHV results. The pour point of the final liquid product met the requirement.

A news magnetic tools designed by ECOPETROL to inhibit wax in the petroleum production systems

Energy Technology Data Exchange (ETDEWEB)

Pelaez U, C.; Medina Z, C. [ECOPETROL, Instituto Colombiano del Petroleo (Colombia); Pena C, A. [INSERPET, Bucaramanga (Colombia)

1996-12-31

The deposition of wax and asphaltenes in production systems cause plugging in the flow lines reducing the oil production and increasing significantly the produced barrels prices. A wax magnetic inhibition technique has been tested with great success. The method has been improved with the use of magnetic tools. This work describes the experience and the results obtained with these tools. 6 figs., 1 tab.

A news magnetic tools designed by ECOPETROL to inhibit wax in the petroleum production systems

Energy Technology Data Exchange (ETDEWEB)

Pelaez U, C; Medina Z, C [ECOPETROL, Instituto Colombiano del Petroleo (Colombia); Pena C, A [INSERPET, Bucaramanga (Colombia)

1997-12-31

The deposition of wax and asphaltenes in production systems cause plugging in the flow lines reducing the oil production and increasing significantly the produced barrels prices. A wax magnetic inhibition technique has been tested with great success. The method has been improved with the use of magnetic tools. This work describes the experience and the results obtained with these tools. 6 figs., 1 tab.

Quality-grade evaluation of petroleum waxes using an electronic nose with a TGS gas sensor array

International Nuclear Information System (INIS)

Wang, Ji; Gao, Daqi; Wang, Zejian

2015-01-01

In this paper, the potential of an improved electronic nose to discriminate the quality of petroleum waxes based on their volatile profile was analyzed. Two datasets at 25 and 50 °C were collected from an experiment in order to compare influence by temperature. More fine-grained levels were further labeled for classification to meet various purposes. As petroleum waxes with lower odor levels are more difficult and important to identify than those with higher odor levels, we focus on the discrimination task for low-level ones. Principal component analysis was used for dimensionality reduction and data visualization. k-nearest neighbors, support vector machine, and multilayer perceptron were employed to classify among different qualities of petroleum waxes. The leave-one-out cross-validation method was employed due to the small sample sizes. Results showed good performance on both datasets, and at a temperature of 50 °C all pattern recognition methods showed improved classification rates. The improved electronic nose can potentially be applied to discriminate the quality of petroleum wax. (paper)

Low-pressure injection molding of alumina ceramics using a carnauba wax binder: preliminary results

Energy Technology Data Exchange (ETDEWEB)

Quevedo Nogueira, R.E.F.; Bezerra, A.C.; Santos, F.C. dos [Dept. de Engenharia Mecanica, Centro de Tecnologia-UFC, Fortaleza, CE (Brazil); Sousa, M.R. de; Acchar, W. [Dept. de Engenharia Mecanica, Univ. Federal do Rio Grande do Norte, UFRN-Campus Univ., Natal, RN (Brazil)

2001-07-01

Carnauba wax, a natural product from Northeastern Brazil, has found application in the processing of ceramics. However, the use of pure carnauba wax is not recommended due to its narrow melting range and poor mechanical properties. In the present work carnauba wax based organic vehicles with the addition of low-density polyethylene and stearic acid were developed for use in the low-pressure injection molding of alumina ceramics. Viscosimetric testing was employed for the determination of optimal composition of the organic vehicle. The optimal content of ceramic powder in the mixture was also determined. All the materials used are easily available in the Brazilian market. A simple ceramic part was injected at low pressures (0.6 MPa) using a semi-automatic injection molding machine. For this purpose a double cavity mold was designed and built. Preliminary results demonstrate the technical viability of the process using the organic vehicle developed. (orig.)

Long-term evaluation of the needle surface wax condition of Pinus sylvestris around different industries in Lithuania

International Nuclear Information System (INIS)

Kupcinskiene, Eugenija; Huttunen, Satu

2005-01-01

The aim of our study was to evaluate the annual dynamics of needle surface wax erosion and wettability in Scots pines exposed to a gradient of industrial pollutants emitted from the main factories of Lithuania: a nitrogen fertilizer factory, an oil refinery and a cement factory. Decreased emissions (in the case of the oil refinery and the cement factory) were reflected in the increased structural surface area (SSA, i.e. area covered by tubular waxes) on the needles. The nearly constant amount of emissions from the nitrogen fertilizer factory within the 1994-2000 period corresponded to negligible annual differences in SSA. Annual changes in the hydrophobicity of needles on the investigated transects were small. Despite the decreased pollution within the 7-year period, industrial emissions are still causing significantly accelerated wax erosion and increased wettability in needles sampled from the stands most heavily affected by pollutants. - Tubular wax on the pine needle surface reflects changes/differences in industrial emissions

Enhanced Thermo-Optical Switching of Paraffin-Wax Composite Spots under Laser Heating.

Science.gov (United States)

Said, Asmaa; Salah, Abeer; Fattah, Gamal Abdel

2017-05-12

Thermo-optical switches are of particular significance in communications networks where increasingly high switching speeds are required. Phase change materials (PCMs), in particular those based on paraffin wax, provide wealth of exciting applications with unusual thermally-induced switching properties, only limited by paraffin's rather low thermal conductivity. In this paper, the use of different carbon fillers as thermal conductivity enhancers for paraffin has been investigated, and a novel structure based on spot of paraffin wax as a thermo-optic switch is presented. Thermo-optical switching parameters are enhanced with the addition of graphite and graphene, due to the extreme thermal conductivity of the carbon fillers. Differential Scanning Calorimetry (DSC) and Scanning electron microscope (SEM) are performed on paraffin wax composites, and specific heat capacities are calculated based on DSC measurements. Thermo-optical switching based on transmission is measured as a function of the host concentration under conventional electric heating and laser heating of paraffin-carbon fillers composites. Further enhancements in thermo-optical switching parameters are studied under Nd:YAG laser heating. This novel structure can be used in future networks with huge bandwidth requirements and electric noise free remote aerial laser switching applications.

Influence of putrescine and carnauba wax on functional and sensory quality of pomegranate (Punica granatum L.) fruits during storage

OpenAIRE

Barman, Kalyan; Asrey, Ram; Pal, R. K.; Kaur, Charanjit; Jha, S. K.

2011-01-01

Functional properties (anthocyanins, antioxidant, ascorbic acid and tannin) and sensory score were determined in pomegranate fruits at two storage temperatures (3 and 5 °C) after treatment with 2 mM putrescine and 1 : 10 carnauba wax (carnauba wax : water). The treatments (putrescine and carnauba wax) were given by immersion method followed by storage up to 60 days. Both treatments retained significantly higher anthocyanins, antioxidant, ascorbic acid, tannin and sensory qualities as compared...

Cross-linking of LDPE/wax blends by using dicumyl peroxide

African Journals Online (AJOL)

Igor Krupa

They are not soluble in many solvents due to their high crystallinity, but they ... macroradical formation via thermal decomposition of organic peroxides.6,7,8 A ... as potential applications of LDPE/wax blends are concerned, lower viscosity of ...

Dental Calculus Arrest of Dental Caries.

Science.gov (United States)

Keyes, Paul H; Rams, Thomas E

An inverse relationship between dental calculus mineralization and dental caries demineralization on teeth has been noted in some studies. Dental calculus may even form superficial layers over existing dental caries and arrest their progression, but this phenomenon has been only rarely documented and infrequently considered in the field of Cariology. To further assess the occurrence of dental calculus arrest of dental caries, this study evaluated a large number of extracted human teeth for the presence and location of dental caries, dental calculus, and dental plaque biofilms. A total of 1,200 teeth were preserved in 10% buffered formal saline, and viewed while moist by a single experienced examiner using a research stereomicroscope at 15-25× magnification. Representative teeth were sectioned and photographed, and their dental plaque biofilms subjected to gram-stain examination with light microscopy at 100× magnification. Dental calculus was observed on 1,140 (95%) of the extracted human teeth, and no dental carious lesions were found underlying dental calculus-covered surfaces on 1,139 of these teeth. However, dental calculus arrest of dental caries was found on one (0.54%) of 187 evaluated teeth that presented with unrestored proximal enamel caries. On the distal surface of a maxillary premolar tooth, dental calculus mineralization filled the outer surface cavitation of an incipient dental caries lesion. The dental calculus-covered carious lesion extended only slightly into enamel, and exhibited a brown pigmentation characteristic of inactive or arrested dental caries. In contrast, the tooth's mesial surface, without a superficial layer of dental calculus, had a large carious lesion going through enamel and deep into dentin. These observations further document the potential protective effects of dental calculus mineralization against dental caries.

Dental Calculus Arrest of Dental Caries

Science.gov (United States)

Keyes, Paul H.; Rams, Thomas E.

2016-01-01

Background An inverse relationship between dental calculus mineralization and dental caries demineralization on teeth has been noted in some studies. Dental calculus may even form superficial layers over existing dental caries and arrest their progression, but this phenomenon has been only rarely documented and infrequently considered in the field of Cariology. To further assess the occurrence of dental calculus arrest of dental caries, this study evaluated a large number of extracted human teeth for the presence and location of dental caries, dental calculus, and dental plaque biofilms. Materials and methods A total of 1,200 teeth were preserved in 10% buffered formal saline, and viewed while moist by a single experienced examiner using a research stereomicroscope at 15-25× magnification. Representative teeth were sectioned and photographed, and their dental plaque biofilms subjected to gram-stain examination with light microscopy at 100× magnification. Results Dental calculus was observed on 1,140 (95%) of the extracted human teeth, and no dental carious lesions were found underlying dental calculus-covered surfaces on 1,139 of these teeth. However, dental calculus arrest of dental caries was found on one (0.54%) of 187 evaluated teeth that presented with unrestored proximal enamel caries. On the distal surface of a maxillary premolar tooth, dental calculus mineralization filled the outer surface cavitation of an incipient dental caries lesion. The dental calculus-covered carious lesion extended only slightly into enamel, and exhibited a brown pigmentation characteristic of inactive or arrested dental caries. In contrast, the tooth's mesial surface, without a superficial layer of dental calculus, had a large carious lesion going through enamel and deep into dentin. Conclusions These observations further document the potential protective effects of dental calculus mineralization against dental caries. PMID:27446993

Mouthwash Use in General Population: Results from Adult Dental Health Survey in Grampian, Scotland

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Kirstin Rhodes

2010-10-01

Full Text Available Objectives: The purpose of this study was to determine the pattern of mouthwash use and to investigate the associated factors in general population.Material and Methods: An Adult Dental Health Survey was conducted on 3,022 residents of Grampian region of Scotland (adjusted participation rate 58.2%. Participants received a questionnaire consisting of questions on oral health and behavioural factors.Results: The majority of participants (38.1% have never used mouthwash, 17.5% used mouthwash less than once a month, 19.4% used mouthwash once every few days and 25.1% used mouthwash daily.Prevalence of use decreased with age (P < 0.001. Woman were more likely to use mouthwash than men (P = 0.004. Mouthwash use decreased with decrease in the level of deprivation (P < 0.001. Never-smokers were less likely to use mouthwash (40.3% compared to smokers (53.1% or those who stopped smoking (46.5% (P < 0.001. Mouthwash was used by smaller proportion of people drinking alcohol on daily basis (36.6%, than by abstainers (42.2% (P = 0.012.There was a positive relationship between flossing or brushing pattern and mouthwash use (P < 0.001. There was statistically significant relationship between mouthwash use and reasons for the last dental visit (P = 0.009.When compared to healthy individuals, mouthwash was used by higher proportion of people reporting that they had gum disease (P = 0.001, ulcers (P = 0.001, oral infections or swelling (P = 0.002 or other problems (P = 0.025.Conclusions: Mouthwash use in general population is associated with socio-demographic, health and behavioural factors.

Leaf waxes in litter and topsoils along a European transect

Czech Academy of Sciences Publication Activity Database

Schäfer, I. K.; Lanny, V.; Franke, J.; Eglinton, T. I.; Zech, M.; Vysloužilová, Barbora; Zech, R.

2016-01-01

Roč. 2, č. 4 (2016), s. 551-564 ISSN 2199-3971 Institutional support: RVO:67985912 Keywords : leaf waxes * soil s Subject RIV: AC - Archeology, Anthropology, Ethnology http://www. soil -journal.net/2/551/2016/ soil -2-551-2016.pdf

Composition of epicuticular wax on Prosopis glandulosa leaves

International Nuclear Information System (INIS)

Mayeux, H.S. Jr.; Wilkinson, R.E.

1990-01-01

Epicuticular wax on leaves of field-grown honey mesquite (Prosopis glandulosa Torr.) trees consisted of 35% esters, 32% alkanes, 25% free fatty alcohols, and 7% free fatty acids. Aldehydes were present in very low concentrations. The number of carbon atoms (C n ) of alkanes ranged from 25 to 31, with a maximum (57%) at 29. Esters consisted of fatty acids with C n of 16, 18, and 20, with most (70%) at 18 and fatty alcohols with C n of 24-32. The C n of free fatty alcohols and free fatty acids also ranged from 24 to 32. Only primary alcohols were present. Immediately after exposure of glasshouse-grown seedlings to 14 CO 2 for 4 h, 60% of the recovered 14 C was incorporated into free fatty acids; the percentage decreased progressively to 18% 8 h after exposure and remained stable thereafter. The proportion of 14 C in free fatty alcohols increased from ca. 12% immediately after exposure to 14 CO 2 to 55% at 8 h. Little 14 C was associated with other wax components over the 24-h period; 3% or less was incorporated into alkanes

Two Predicted Transmembrane Domains Exclude Very Long Chain Fatty acyl-CoAs from the Active Site of Mouse Wax Synthase.

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Steffen Kawelke

Full Text Available Wax esters are used as coatings or storage lipids in all kingdoms of life. They are synthesized from a fatty alcohol and an acyl-CoA by wax synthases. In order to get insights into the structure-function relationships of a wax synthase from Mus musculus, a domain swap experiment between the mouse acyl-CoA:wax alcohol acyltransferase (AWAT2 and the homologous mouse acyl-CoA:diacylglycerol O-acyltransferase 2 (DGAT2 was performed. This showed that the substrate specificity of AWAT2 is partially determined by two predicted transmembrane domains near the amino terminus of AWAT2. Upon exchange of the two domains for the respective part of DGAT2, the resulting chimeric enzyme was capable of incorporating up to 20% of very long acyl chains in the wax esters upon expression in S. cerevisiae strain H1246. The amount of very long acyl chains in wax esters synthesized by wild type AWAT2 was negligible. The effect was narrowed down to a single amino acid position within one of the predicted membrane domains, the AWAT2 N36R variant. Taken together, we provide first evidence that two predicted transmembrane domains in AWAT2 are involved in determining its acyl chain length specificity.

Application of carnauba-based wax maintains postharvest quality of 'Ortanique' tangor

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Francisca Ligia de Castro Machado

2012-06-01

Full Text Available This study aimed at evaluating compositional changes in the quality of 'Ortanique' tangor after coating with the carnauba-based waxes Aruá Tropical® or Star Light®. The storage conditions studied simulated those of local marketing (22 ± 2 °C, 60 ± 5% RH. Non-destructive analysis, mass loss, peel color, and sensory evaluation, were performed upon coating and every three days up to the fifteenth day of storage. Destructive analysis, peel moisture content, chlorophyll of the peel, pulp color, juice content, soluble solids (SS, titratable acidity (TA, pH, and soluble solids to titratable acidity ratio, were performed upon coating and every four days up to the sixteenth day of storage. The assay was conducted using an entirely randomized design, with three replications (destructive analyses or ten replications (non-destructive analyses, in a split plot scheme. Wax-coating, especially Aruá Tropical®, maintained fruit freshness by reducing mass loss and peel dehydration and retaining green color. Peel moisture content, chlorophyll content, and juice content had lower rates in the wax coated fruits. Puncture force, soluble solids, titratable acidity, pH, and soluble solids to titratable acidity ratio varied vary little over the course of storage. Sensory evaluation showed that the application of Aruá Tropical keeps 'Ortanique' tangor fresher for 6 days longer for commercialization.

Pretreatment oral hygiene habits and survival of head and neck squamous cell carcinoma (HNSCC) patients.

Science.gov (United States)

Friemel, Juliane; Foraita, Ronja; Günther, Kathrin; Heibeck, Mathias; Günther, Frauke; Pflueger, Maren; Pohlabeln, Hermann; Behrens, Thomas; Bullerdiek, Jörn; Nimzyk, Rolf; Ahrens, Wolfgang

2016-03-11

The survival time of patients with head and neck squamous cell carcinoma (HNSCC) is related to health behavior, such as tobacco smoking and alcohol consumption. Poor oral health (OH), dental care (DC) and the frequent use of mouthwash have been shown to represent independent risk factors for head and neck cancerogenesis, but their impact on the survival of HNSCC patients has not been systematically investigated. Two hundred seventy-six incident HNSCC cases recruited for the ARCAGE study were followed through a period of 6-10 years. Interview-based information on wearing of dentures, gum bleeding, teeth brushing, use of floss and dentist visits were grouped into weighted composite scores, i.e. oral health (OH) and dental care (DH). Use of mouthwash was assessed as frequency per day. Also obtained were other types of health behavior, such as smoking, alcohol drinking and diet, appreciated as both confounding and study variables. Endpoints were progression-free survival, overall survival and tumor-specific survival. Prognostic values were estimated using Kaplan-Meier analysis and Cox proportional hazards regression models. A good dental care score, summarizing annual dental visits, daily teeth cleaning and use of floss was associated with longer overall survival time (p = .001). The results of the Cox regression models similarly suggested a higher risk of tumor progression and shortened overall survival in patients with poor dental care, but the results lost their statistical significance after other types of health behavior had been controlled for. Frequent use of mouthwash (≥ 2 times/day) significantly increased the risk of tumor-specific death (HR = 2.26; CI = 1.19-4.32). Alcohol consumption and tobacco smoking were dose-dependently associated with tumor progression and shorter overall survival. Frequent mouthwash use of ≥ 2 times/day seems to elevate the risk of tumor-specific death in HNSCC patients. Good dental care scores are associated with longer overall

Heritability of the Structures and 13C Fractionation in Tomato Leaf Wax Alkanes: A Genetic Model System to Inform Paleoenvironmental Reconstructions

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Amanda L. D. Bender

2017-06-01

Full Text Available Leaf wax n-alkanes are broadly used to reconstruct paleoenvironmental information. However, the utility of n-alkanes as a paleoenvironmental proxy may be modulated by the extent to which biological as well as environmental factors influence the structural and isotopic variability of leaf waxes. In paleoclimate applications, there is usually an implicit assumption that most variation of leaf wax traits through a time series can be attributed to environmental change and that biological sources of variability within plant communities are small. For example, changes in hydrology affect the δ2H of waxes via rainwater and the δ13C of leaf waxes by changing plant communities. We measured the degree of genetic control over δ13C variation in leaf waxes within closely related species with an experimental greenhouse growth study. We measured the proportion of variability in structural and isotopic leaf wax traits that is attributable to genetic variation using a set of 76 introgression lines (ILs between two interfertile Solanum (tomato species: S. lycopersicum cv M82 (hereafter cv M82 and S. pennellii. Leaves of S. pennellii, a wild desert tomato relative, produced significantly more iso-alkanes than cv M82, a domesticated tomato cultivar adapted to water-replete conditions. We report a methylation index to summarize the ratio of branched (iso- and anteiso- to total alkanes. Between Solanum pennellii and cv M82, the iso-alkanes were found to be enriched in 13C by 1.2–1.4‰ over n-alkanes. The broad-sense heritability values (H2 of leaf wax traits describe the degree to which genetic variation contributes to variation of these traits. Variation of individual carbon isotopic compositions of alkanes were of low heritability (H2 = 0.13–0.19, suggesting that most variation in δ13C of leaf waxes in this study can be attributed to environmental variance. This supports the interpretation that variation in the δ13C of wax compounds recorded in sediments

Heritability of the structures and 13C fractionation in tomato leaf wax alkanes: a genetic model system to inform paleoenvironmental reconstructions

Science.gov (United States)

Bender, Amanda L. D.; Chitwood, Daniel H.; Bradley, Alexander S.

2017-06-01

Leaf wax n-alkanes are broadly used to reconstruct paleoenvironmental information. However, the utility of n-alkanes as a paleoenvironmental proxy may be modulated by the extent to which biological as well as environmental factors influence the structural and isotopic variability of leaf waxes. In paleoclimate applications, there is usually an implicit assumption that most variation of leaf wax traits through a time series can be attributed to environmental change and that biological sources of variability within plant communities are small. For example, changes in hydrology affect the δ2H of waxes via rainwater and the δ13C of leaf waxes by changing plant communities. We measured the degree of genetic control over δ13C variation in leaf waxes within closely related species with an experimental greenhouse growth study. We measured the proportion of variability in structural and isotopic leaf wax traits that is attributable to genetic variation using a set of 76 introgression lines (ILs) between two interfertile Solanum (tomato) species: S. lycopersicum cv M82 (hereafter cv M82) and S. pennellii. Leaves of S. pennellii, a wild desert tomato relative, produced significantly more iso-alkanes than cv M82, a domesticated tomato cultivar adapted to water-replete conditions. We report a methylation index to summarize the ratio of branched (iso- and anteiso-) to total alkanes. Between S. pennellii and cv M82, the iso-alkanes were found to be enriched in 13C by 1.2-1.4‰ over n-alkanes. The broad-sense heritability values (H2) of leaf wax traits describe the degree to which genetic variation contributes to variation of these traits. Variation of individual carbon isotopic compositions of alkanes were of low heritability (H2 = 0.13-0.19), suggesting that most variation in δ13C of leaf waxes in this study can be attributed to environmental variance. This supports the interpretation that variation in the δ13C of wax compounds recorded in sediments reflects

Surfactants from petroleum paraffin wax

Energy Technology Data Exchange (ETDEWEB)

Kassem, T.M.; Hussein, M.H.; El Sayed, A.S.

Paraffin wax from Egyptian petroleum was purified and then oxidized to fatty acids which were esterified to form their methyl esters, fractionated and then hydrolysed. The obtained fatty acids were converted into the corresponding primary amines which were converted with ethylene oxide to form nonionic surfactants. The prepared primary amines were also converted into tertiary amines and then converted into cationic surfactants through condensation with benzyl chloride or 1-chloromethylnaphthalene. Also, amine oxide surfactants were prepared by oxidation of the tertiary amines with hydrogen peroxide. The surface active properties of all the prepared surfactants were determined, and the effect of their chemical structure on the surfactant properties are discussed in this paper.

A prediction method for the wax deposition rate based on a radial basis function neural network

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Ying Xie

2017-06-01

Full Text Available The radial basis function neural network is a popular supervised learning tool based on machinery learning technology. Its high precision having been proven, the radial basis function neural network has been applied in many areas. The accumulation of deposited materials in the pipeline may lead to the need for increased pumping power, a decreased flow rate or even to the total blockage of the line, with losses of production and capital investment, so research on predicting the wax deposition rate is significant for the safe and economical operation of an oil pipeline. This paper adopts the radial basis function neural network to predict the wax deposition rate by considering four main influencing factors, the pipe wall temperature gradient, pipe wall wax crystal solubility coefficient, pipe wall shear stress and crude oil viscosity, by the gray correlational analysis method. MATLAB software is employed to establish the RBF neural network. Compared with the previous literature, favorable consistency exists between the predicted outcomes and the experimental results, with a relative error of 1.5%. It can be concluded that the prediction method of wax deposition rate based on the RBF neural network is feasible.

Characterization of rice bran wax policosanol and its nanoemulsion formulation

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Ishaka A

2014-05-01

Full Text Available Aminu Ishaka,1,2 Mustapha Umar Imam,1 Rozi Mahamud,3 Abu Bakar Zakaria Zuki,4 Ismail Maznah1 1Laboratory of Molecular Biomedicine, Institute of Bioscience, University Putra Malaysia, Serdang, Selangor, Malaysia; 2Department of Medical Biochemistry, College of Health Sciences, Usmanu Danfodiyo University, Sokoto, Nigeria; 3Faculty of Medicine and Health Sciences, 4Faculty of Veterinary Medicine, University Putra Malaysia, Serdang, Selangor, Malaysia Abstract: Policosanol, a mixture of long-chain alcohols found in animal and plant waxes, has several biological effects; however, it has a bioavailability of less than 10%. Therefore, there is a need to improve its bioavailability, and one of the ways of doing this is by nanoemulsion formulation. Different droplet size distributions are usually achieved when emulsions are formed, which solely depends on the preparation method used. Mostly, emulsions are intended for better delivery with maintenance of the characteristics and properties of the leading components. In this study, policosanol was extracted from rice bran wax, its composition was determined by gas chromatography mass spectrophotometry, nanoemulsion was made, and the physical stability characteristics were determined. The results showed that policosanol nanoemulsion has a nanosize particle distribution below 100 nm (92.56–94.52 nm, with optimum charge distribution (-55.8 to -45.12 mV, pH (6.79–6.92 and refractive index (1.50; these were monitored and found to be stable for 8 weeks. The stability of policosanol nanoemulsion confers the potential to withstand long storage times. Keywords: rice bran wax, policosanol, nanoemulsion, characterization

The effect of waxes, as a complement to hydrothermal immersion, on the quality of papaya fruit (Carica papaya L. Pococí hybrid

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V. Gustavo Corra

2015-06-01

Full Text Available Different waxes were evaluated as a complement to hydrothermal treatment on the overall papaya fruit quality parameters. The fruits were harvested, washed in water, disinfected with sodium hypochlorite and exposed to hydrothermal immersion treatment at 49°C/20 min (HT; then treatments were applied: 1 bees wax +palm oil 5% solution; 2 fatty acids wax mixture 4.7%; 3 chitosan 0.1%; 4 only HT; 5 control (no hydrothermal immersion nor wax. The fruit was stored for 15 days at 12°C, then at 20°C. Significant differences (p≤0.05 were found between fruits receiving HT complemented with 5% bees + palm oil wax, which exhibited lower respiration rate (12.27 ml CO2/kg*h a 8 days after leaving cold storage, as compared with those receiving only HT (16.72 ml CO2/ kg*h or control fruits (17.01 ml CO2/kg*h. The lesser percent of acumulated weight loss was registered whit TH plus bees wax cund palm oil. The color parameters were not affected, except for treatment 2, fatty acids wax mixture, which induced a delay in color development (p≤0.05. No changes were observed in internal or external firmness, nor in degrees brix. HT reduced the incidence of peduncular rot and anthracnose severity (p≤0.05, and extended useful life time. The use of waxes as a complement to HT can contribute to preserving some of the parameters which influence the final papaya fruit quality.

Effect of matrix granulation and wax coating on the dissolution rates ...

African Journals Online (AJOL)

disintegrating) granules consisting of paracetamol (drug) and acrylatemethacrylate copolymer, a matrix forming material. The effect of coating the matrix granules with wax on the drug release profiles was also investigated. The objective was to ...

Water Activated Graphene Oxide Transfer Using Wax Printed Membranes for Fast Patterning of a Touch Sensitive Device.

Science.gov (United States)

Baptista-Pires, Luis; Mayorga-Martínez, Carmen C; Medina-Sánchez, Mariana; Montón, Helena; Merkoçi, Arben

2016-01-26

We demonstrate a graphene oxide printing technology using wax printed membranes for the fast patterning and water activation transfer using pressure based mechanisms. The wax printed membranes have 50 μm resolution, longtime stability and infinite shaping capability. The use of these membranes complemented with the vacuum filtration of graphene oxide provides the control over the thickness. Our demonstration provides a solvent free methodology for printing graphene oxide devices in all shapes and all substrates using the roll-to-roll automatized mechanism present in the wax printing machine. Graphene oxide was transferred over a wide variety of substrates as textile or PET in between others. Finally, we developed a touch switch sensing device integrated in a LED electronic circuit.

Insecticidal Properties of a Highly Potent Wax Isolated from Dolichandra cynanchoides Cham

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Georgina Díaz Napal

2016-08-01

Full Text Available Bioassay-guided fractionation of an ethanolic extract of the aerial parts of Dolichandra cynanchoides Cham. (Bignoniaceae led to the isolation of a natural wax with anti-insect activity against Spodoptera frugiperda (Noctuidae and Epilachna paenulata (Coleptera. The compound was identified spectroscopically as an ester of a C27 fatty acid and a C25 alcohol, pentacosyl heptacosanoate (1. The effective doses of 1 for 50% feeding inhibition (ED50 of S. frugiperda and E. paenulata were 0.82 and 8.53 µg/cm2, respectively, in a choice test, while azadirachtin showed ED50 of 0.10 and 0.59 µg/cm2, respectively. In a no-choice test, both insects refused to feed on leaves treated with 1 at doses of 0.1 µg/cm2 or greater inhibiting larval growth and dramatically reducing survival. The lethal doses 50 (LD50 of 1 were 0.39 and 0.68 µg/cm2 for S. frugiperda and E. paenulata, respectively. These results indicate that 1 has potential for development as botanical insecticides. Similar esters might be obtainable in large quantities as many edible crops produce wax esters that are discarded during food processing. Research on these materials could lead to the detection of similar waxes with insecticidal activity.

High-level accumulation of oleyl oleate in plant seed oil by abundant supply of oleic acid substrates to efficient wax ester synthesis enzymes.

Science.gov (United States)

Yu, Dan; Hornung, Ellen; Iven, Tim; Feussner, Ivo

2018-01-01

Biotechnology enables the production of high-valued industrial feedstocks from plant seed oil. The plant-derived wax esters with long-chain monounsaturated acyl moieties, like oleyl oleate, have favorite properties for lubrication. For biosynthesis of wax esters using acyl-CoA substrates, expressions of a fatty acyl reductase (FAR) and a wax synthase (WS) in seeds are sufficient. For optimization of the enzymatic activity and subcellular localization of wax ester synthesis enzymes, two fusion proteins were created, which showed wax ester-forming activities in Saccharomyces cerevisiae . To promote the formation of oleyl oleate in seed oil, WSs from Acinetobactor baylyi ( Ab WSD1) and Marinobacter aquaeolei ( Ma WS2), as well as the two created fusion proteins were tested in Arabidopsis to evaluate their abilities and substrate preference for wax ester production. The tested seven enzyme combinations resulted in different yields and compositions of wax esters. Expression of a FAR of Marinobacter aquaeolei ( Ma FAR) with Ab WSD1 or Ma WS2 led to a high incorporation of C 18 substrates in wax esters. The Ma FAR/TM Mm AWAT2- Ab WSD1 combination resulted in the incorporation of more C 18:1 alcohol and C 18:0 acyl moieties into wax esters compared with Ma FAR/ Ab WSD1. The fusion protein of a WS from Simmondsia chinensis ( Sc WS) with MaFAR exhibited higher specificity toward C 20:1 substrates in preference to C 18:1 substrates. Expression of Ma FAR/ Ab WSD1 in the Arabidopsis fad2 fae1 double mutant resulted in the accumulation of oleyl oleate (18:1/18:1) in up to 62 mol% of total wax esters in seed oil, which was much higher than the 15 mol% reached by Ma FAR/ Ab WSD1 in Arabidopsis Col-0 background. In order to increase the level of oleyl oleate in seed oil of Camelina , lines expressing Ma FAR/ Sc WS were crossed with a transgenic high oleate line. The resulting plants accumulated up to >40 mg g seed -1 of wax esters, containing 27-34 mol% oleyl oleate. The

In vitro erythemal UV-A protection factors of inorganic sunscreens distributed in aqueous media using carnauba wax-decyl oleate nanoparticles.

Science.gov (United States)

Villalobos-Hernández, J R; Müller-Goymann, C C

2007-01-01

This paper describes the in vitro photoprotection in the UV-A range, i.e. 320-400 nm obtained by the use of carnauba wax-decyl oleate nanoparticles either as encapsulation systems or as accompanying vehicles for inorganic sunscreens such as barium sulfate, strontium carbonate and titanium dioxide. Lipid-free inorganic sunscreen nanosuspensions, inorganic sunscreen-free wax-oil nanoparticle suspensions and wax-oil nanoparticle suspensions containing inorganic sunscreens dispersed either in their oil phase or their aqueous phase were prepared by high pressure homogenization. The in vitro erythemal UV-A protection factors (EUV-A PFs) of the nanosuspensions were calculated by means of a sun protection analyzer. EUV-A PFs being no higher than 4 were obtained by the encapsulation of barium sulfate and strontium carbonate, meanwhile by the distribution of titanium dioxide in presence of wax-oil nanoparticles, the EUV-A PFs varied between 2 and 19. The increase in the EUV-A PFs of the titanium dioxide obtained by the use of wax-oil nanoparticles demonstrated a better performance of the sun protection properties of this pigment in the UV-A region.

Experimental analysis, modeling and simulation of a solar energy accumulator with paraffin wax as PCM

International Nuclear Information System (INIS)

Reyes, A.; Henríquez-Vargas, L.; Aravena, R.; Sepúlveda, F.

2015-01-01

Highlights: • Enhancement of paraffin wax thermal conductivity using soft drink can stripes. • Thermal analysis and simulations results agree well with experimental data. • Increase in accumulator thermal efficiencies through addition of external aluminum stripes. • Proposed accumulator allows up to 13,000 kJ of energy storage. - Abstract: Soft drink cans filled with paraffin wax mixed with 7.5% aluminum stripes, obtained from disposable cans, doubled the thermal conductivity of cans filled only with paraffin wax. Promising results obtained in a prototype heat exchanger encouraged the construction of this unit 6 times bigger. We experimentally evaluated and model a heat exchanger for solar energy accumulation, composed by 300 disposable soft drink cans filled with a total of 59.25 kg of paraffin wax mixed with 7.5% aluminum stripes. The effect of adding 2.75 kg of aluminum fins for enhancing heat transfer from the outer surface of the cans to the circulant air was experimentally analyzed. In sunny days, the wax melted completely in about 4 h. The accumulated energy in form of latent heat (about 13,000 kJ) allowed to increase the temperature of 0.040 kg/s of circulant air in at least 20 °C during a period of 2.5 h. For an air mass rate of 0.018 kg/s the period was extended practically to 5 h. The accumulator thermal analysis was presented and a subsequent numerical simulation with Matlab was performed to compare with the experimental results obtaining good agreement specially for higher air mass flow rates. The low cost accumulator presented is of simple construction and will allow extended use of solar energy for applications such as drying processes or household calefaction system.

Molecular analysis of intact preen waxes of Calidris Canutus (Aves: Scolopacidae) by GC/MS and GC/MS/MS

NARCIS (Netherlands)

Sinninghe Damsté, J.S.; Dekker, M.H.A.; Piersma, T.

2000-01-01

The intact preen wax esters of the red knot Calidris canutus were studied with gas chromatography/mass spectrometry (GC/MS) and GC/MS/MS. In this latter technique, transitions from the molecular ion to fragment ions representing the fatty acid moiety of the wax esters were measured, providing

Development of Wax-Incorporated Emulsion Gel Beads for the Encapsulation and Intragastric Floating Delivery of the Active Antioxidant from Tamarindus indica L.

Science.gov (United States)

Soradech, Sitthiphong; Petchtubtim, Intira; Thongdon-A, Jeerayu; Muangman, Thanchanok

2016-03-22

In this study, tamarind (Tamarindus indica L.) seed extracts with potential antioxidant activity and toxicity to cancer cells were developed as functional foods and nutraceutical ingredients in the form of emulsion gel beads. Three extracts were obtained from ethanol and water: TSCH50, TSCH95 and TSCH. All extracts exhibited high potential for superoxide anion scavenging activity over the IC50 range emulsion gel beads, which were prepared using a modified ionotropic gelation technique. Tamarind seed extract at 1% (w/w) was used as the active ingredient in all formulations. The effect of the types and amounts of wax on the encapsulation efficiency and percentage of the active release of alginate gel beads was also investigated. The results demonstrated that the incorporation of both waxes into the gel beads had an effect on the percentage of encapsulation efficiency (%) and the percentage of the active ingredient release. Furthermore, the addition of water insoluble waxes (carnauba and bee wax) significantly retarded the release of the active ingredient. The addition of both waxes had a slight effect on drug release behavior. Nevertheless, the increase in incorporated waxes in all formulations could sustain the percentage of active ingredient release. In conclusion, wax-incorporated emulsion gel beads using a modified ionotropic gelation technique could be applied for the intragastric floating delivery and controlled release of functional food and nutraceutical products for their antioxidant and anticancer capacity.

Surfactant-free carnauba wax dispersion and its use for layer-by-layer assembled protective surface coatings on wood

Science.gov (United States)

Lozhechnikova, Alina; Bellanger, Hervé; Michen, Benjamin; Burgert, Ingo; Österberg, Monika

2017-02-01

Protection from liquid water and UV radiation are equally important, and a sophisticated approach is needed when developing surface coatings that preserve the natural and well-appreciated aesthetic appearance of wood. In order to prevent degradation and prolong the service life of timber, a protective coating was assembled using carnauba wax particles and zinc oxide nanoparticles via layer-by-layer deposition in water. For this purpose, a facile sonication route was developed to produce aqueous wax dispersion without any surfactants or stabilizers. The suspension was stable above pH 4 due to the electrostatic repulsion between the negatively charged wax particles. The particle size could be controlled by the initial wax concentration with average particle sizes ranging from 260 to 360 nm for 1 and 10 g/L, respectively. The deposition of wax particles onto the surface of spruce wood introduced additional roughness to the wood surface at micron level, while zinc oxide provided nano roughness and UV-absorbing properties. In addition to making wood superhydrophobic, this novel multilayer coating enhanced the natural moisture buffering capability of spruce. Moreover, wood surfaces prepared in this fashion showed a significant reduction in color change after exposure to UV light. A degradation of the wax through photocatalytic activity of the ZnO particles was measured by FTIR, indicating that further studies are required to achieve long-term stability. Nevertheless, the developed coating showed a unique combination of superhydrophobicity and excellent moisture buffering ability and some UV protection, all achieved using an environmentally friendly coating process, which is beneficial to retain the natural appearance of wood and improve indoor air quality and comfort.

SoftWAXS: a computational tool for modeling wide-angle X-ray solution scattering from biomolecules.

Science.gov (United States)

Bardhan, Jaydeep; Park, Sanghyun; Makowski, Lee

2009-10-01

This paper describes a computational approach to estimating wide-angle X-ray solution scattering (WAXS) from proteins, which has been implemented in a computer program called SoftWAXS. The accuracy and efficiency of SoftWAXS are analyzed for analytically solvable model problems as well as for proteins. Key features of the approach include a numerical procedure for performing the required spherical averaging and explicit representation of the solute-solvent boundary and the surface of the hydration layer. These features allow the Fourier transform of the excluded volume and hydration layer to be computed directly and with high accuracy. This approach will allow future investigation of different treatments of the electron density in the hydration shell. Numerical results illustrate the differences between this approach to modeling the excluded volume and a widely used model that treats the excluded-volume function as a sum of Gaussians representing the individual atomic excluded volumes. Comparison of the results obtained here with those from explicit-solvent molecular dynamics clarifies shortcomings inherent to the representation of solvent as a time-averaged electron-density profile. In addition, an assessment is made of how the calculated scattering patterns depend on input parameters such as the solute-atom radii, the width of the hydration shell and the hydration-layer contrast. These results suggest that obtaining predictive calculations of high-resolution WAXS patterns may require sophisticated treatments of solvent.

Comparison of Dental Prostheses Cast and Sintered by SLM from Co-Cr-Mo-W Alloy

Directory of Open Access Journals (Sweden)

Myszka D.

2016-12-01

Full Text Available The article presents the results of a comparative analysis of the metal substructure for dental prosthesis made from a Co-Cr-Mo-W alloy by two techniques, i.e. precision investment casting and selective laser melting (SLM. It was found that the roughness of the raw surface of the SLM sinter is higher than the roughness of the cast surface, which is compensated by the process of blast cleaning during metal preparation for the application of a layer of porcelain. Castings have a dendritic structure, while SLM sinters are characterized by a compact, fine-grain microstructure of the hardness higher by about 100 HV units. High performance and high costs of implementation the SLM technology are the cause to use it for the purpose of many dental manufacturers under outsourcing rules. The result is a reduction in manufacturing costs of the product associated with dental work time necessary to scan, designing and treatment of sinter compared with the time needed to develop a substructure in wax, absorption in the refractory mass, casting, sand blasting and finishing. As a result of market competition and low cost of materials, sinter costs decrease which brings the total costs related to the construction unit making using the traditional method of casting, at far less commitment of time and greater predictability and consistent sinter quality.

Leaf waxes of slow-growing alpine and fast-growing lowland Poa species: inherent differences and responses to UV-B radiation

International Nuclear Information System (INIS)

Pilon, J.J.; Lambers, H.; Baas, W.; Tosserams, M.; Rozema, J.; Atkin, O.K.

1999-01-01

We investigated whether alpine and lowland Poa species exhibit inherent differences in leaf cuticular waxes, leaf UV absorbing compounds and/or growth responses to UV-B treatment. All plants were grown hydroponically in a growth cabinet (constant 20°; 14 hr photoperiod; 520 μmol photons m −2 s −1 PAR). Two alpine (P. fawcettiae and P. costiniana), one sub-alpine (P. alpina) and three temperate lowland species (P. pratensis, P. compressa and P. trivialis) were grown under conditions without UV radiation for 36 days. In a subsequent experiment, four Poa species (P. costiniana, P. alpina, P. compressa and P. trivialis) were also exposed for 21 days to UV-B/(UV-A) radiation ('UV-B treatment') that resulted in daily UV-B radiation of 7.5 kJ m −2 day −1 , with control plants being grown without UV-B ('UV-A control treatment'). All treatments were carried out in the same growth cabinet. There was no altitudinal trend regarding wax concentrations per unit leaf area, when the six species grown under UV-less conditions, were compared at similar developmental stage (20–30 g shoot fresh mass). However, large differences in cuticular wax chemical composition were observed between the alpine and lowland species grown under UV-less conditions. For example, a single primary alcohol was present in the waxes of the lowland and sub-alpine species (C 26 H 53 OH), but was virtually absent in the alpine species. Although alkanes were present in all six species (primarily C 29 H 60 and C 31 H 64 ), the proportion of total wax present as alkanes was highest in the alpine species. Aldehydes were only present in the waxes of the alpine species. Conversely, substantial amounts of triterpenoids were mainly present in the three lowland species (squalene and lupeol were the dominant forms). The proportion of total wax present as long-chain esters (LCE-s) was similar in all six species grown in the absence of UV radiation. Acetates were observed only in the wax of

Evaluation of shrinkage polymerization and temperature of different acrylic resins used to splinting transfer copings in indirect impression technique

Science.gov (United States)

Franco, Ana Paula G. O.; Karam, Leandro Z.; Galvão, José R.; Kalinowski, Hypolito J.

2015-09-01

The aim of the present study was evaluate the shrinkage polymerization and temperature of different acrylic resins used to splinting transfer copings in indirect impression technique. Two implants were placed in an artificial bone, with the two transfer copings joined with dental floss and acrylic resins; two dental resins are used. Measurements of deformation and temperature were performed with Fiber Braggs grating sensor for 17 minutes. The results revealed that one type of resin shows greater values of polymerization shrinkage than the other. Pattern resins did not present lower values of shrinkage, as usually reported by the manufacturer.

Structural characterization of wax esters by electron ionization mass spectrometry

Czech Academy of Sciences Publication Activity Database

Urbanová, Klára; Vrkoslav, Vladimír; Valterová, Irena; Háková, Martina; Cvačka, Josef

2012-01-01

Roč. 53, č. 1 (2012), s. 204-213 ISSN 0022-2275 R&D Projects: GA ČR GA203/09/0139 Institutional research plan: CEZ:AV0Z40550506 Keywords : interpretation * neutral lipids * spectral database * waxes Subject RIV: CC - Organic Chemistry Impact factor: 4.386, year: 2012

Effects of wax treatment on quality and postharvest physiology of ...

African Journals Online (AJOL)

... cell membrane permeability and malondialdehyde content when compared with those in control. This waxing also improved total sugars and the contents of ascorbic acid in pineapple fruits. These results suggested that this treatment might be a useful technique to alleviate chilling injury and maintain fruit quality during ...

Computer-assisted navigational surgery enhances safety in dental implantology.

Science.gov (United States)

Ng, F C; Ho, K H; Wexler, A

2005-06-01

Dental implants are increasingly used to restore missing dentition. These titanium implants are surgically installed in the edentulous alveolar ridge and allowed to osteointegrate with the bone during the healing phase. After osseo-integration, the implant is loaded with a prosthesis to replace the missing tooth. Conventional implant treatment planning uses study models, wax-ups and panoramic x-rays to prefabricate surgical stent to guide the preparation of the implant site. The drilling into the alveolar ridge is invariably a "blind" procedure as the part of the drill in bone is not visible. Stereotactic systems were first introduced into neurosurgery in 1986. Since then, computer-assisted navigational technology has brought major advances to neuro-, midface and orthopaedic surgeries, and more recently, to implant placement. This paper illustrates the use of real-time computer-guided navigational technology in enhancing safety in implant surgical procedures. Real-time computer-guided navigational technology enhances accuracy and precision of the surgical procedure, minimises complications and facilitates surgery in challenging anatomical locations.

Dental Calculus Arrest of Dental Caries

OpenAIRE

Keyes, Paul H.; Rams, Thomas E.

2016-01-01

Background An inverse relationship between dental calculus mineralization and dental caries demineralization on teeth has been noted in some studies. Dental calculus may even form superficial layers over existing dental caries and arrest their progression, but this phenomenon has been only rarely documented and infrequently considered in the field of Cariology. To further assess the occurrence of dental calculus arrest of dental caries, this study evaluated a large number of extracted human t...

Popliteal versus tibial retrograde access for subintimal arterial flossing with antegrade-retrograde intervention (SAFARI) technique.

Science.gov (United States)

Hua, W R; Yi, M Q; Min, T L; Feng, S N; Xuan, L Z; Xing, J

2013-08-01

This study aimed to ascertain differences in benefit and effectiveness of popliteal versus tibial retrograde access in subintimal arterial flossing with the antegrade-retrograde intervention (SAFARI) technique. This was a retrospective study of SAFARI-assisted stenting for long chronic total occlusion (CTO) of TASC C and D superficial femoral lesions. 38 cases had superficial femoral artery lesions (23 TASC C and 15 TASC D). All 38 cases underwent SAFARI-assisted stenting. The ipsilateral popliteal artery was retrogradely punctured in 17 patients. A distal posterior tibial (PT) or dorsalis pedis (DP) artery was retrogradely punctured in 21 patients, and 16 of them were punctured after open surgical exposure. SAFARI technical success was achieved in all cases. There was no significant difference in 1-year primary patency (75% vs. 78.9%, p = .86), secondary patency (81.2% vs. 84.2%, p = .91) and access complications (p = 1.00) between popliteal and tibial retrograde access. There was statistical difference in operation time between popliteal (140.1 ± 28.4 min) and tibial retrograde access with PT/DP punctures after surgical vessel exposure (120.4 ± 23.0 min, p = .04). The SAFARI technique is a safe and feasible option for patients with infrainguinal CTO (TASC II C and D). The PT or DP as the retrograde access after surgical vessel exposure is a good choice when using the SAFARI technique. Copyright © 2013 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

Terahertz pulsed imaging study of dental caries

Science.gov (United States)

Karagoz, Burcu; Altan, Hakan; Kamburoglu, Kıvanç

2015-07-01

Current diagnostic techniques in dentistry rely predominantly on X-rays to monitor dental caries. Terahertz Pulsed Imaging (TPI) has great potential for medical applications since it is a nondestructive imaging method. It does not cause any ionization hazard on biological samples due to low energy of THz radiation. Even though it is strongly absorbed by water which exhibits very unique chemical and physical properties that contribute to strong interaction with THz radiation, teeth can still be investigated in three dimensions. Recent investigations suggest that this method can be used in the early identification of dental diseases and imperfections in the tooth structure without the hazards of using techniques which rely on x-rays. We constructed a continuous wave (CW) and time-domain reflection mode raster scan THz imaging system that enables us to investigate various teeth samples in two or three dimensions. The samples comprised of either slices of individual tooth samples or rows of teeth embedded in wax, and the imaging was done by scanning the sample across the focus of the THz beam. 2D images were generated by acquiring the intensity of the THz radiation at each pixel, while 3D images were generated by collecting the amplitude of the reflected signal at each pixel. After analyzing the measurements in both the spatial and frequency domains, the results suggest that the THz pulse is sensitive to variations in the structure of the samples that suggest that this method can be useful in detecting the presence of caries.

Presence of carotinoids in peat wax

Energy Technology Data Exchange (ETDEWEB)

Yurkevich, E.A.; Dolidovich, E.F.; Bel' kevich, P.I.; Sheremet, L.S.; Drozdovskaya, S.V.

1986-05-01

Discusses biologically active substances present in peat which have various pharmacological properties. Describes separation of fractions rich in carotinoids from extracts of wax tar obtained by benzine treatment of highly decomposed pine-cotton grass peat. Extraction was carried out using hot ethanol. States that although identification of individual carotinoid in the fractions separated is very difficult due to complicity of composition, the tests carried out made it possible to infer that fractions studied contain not only xanthophylls but also fucoxanthains (formed in small amounts in nature) with fairly stable structure. Ultraviolet and infrared spectra of the carotinoid containing fraction in ethanol extracts are given. 6 refs.

Accelerated Thermal Cycling Test of Microencapsulated Paraffin Wax/Polyaniline Made by Simple Preparation Method for Solar Thermal Energy Storage.

Science.gov (United States)

Silakhori, Mahyar; Naghavi, Mohammad Sajad; Metselaar, Hendrik Simon Cornelis; Mahlia, Teuku Meurah Indra; Fauzi, Hadi; Mehrali, Mohammad

2013-04-29

Microencapsulated paraffin wax/polyaniline was prepared using a simple in situ polymerization technique, and its performance characteristics were investigated. Weight losses of samples were determined by Thermal Gravimetry Analysis (TGA). The microencapsulated samples with 23% and 49% paraffin showed less decomposition after 330 °C than with higher percentage of paraffin. These samples were then subjected to a thermal cycling test. Thermal properties of microencapsulated paraffin wax were evaluated by Differential Scanning Calorimeter (DSC). Structure stability and compatibility of core and coating materials were also tested by Fourier transform infrared spectrophotometer (FTIR), and the surface morphology of the samples are shown by Field Emission Scanning Electron Microscopy (FESEM). It has been found that the microencapsulated paraffin waxes show little change in the latent heat of fusion and melting temperature after one thousand thermal recycles. Besides, the chemical characteristics and structural profile remained constant after one thousand thermal cycling tests. Therefore, microencapsulated paraffin wax/polyaniline is a stable material that can be used for thermal energy storage systems.

Development of Wax-Incorporated Emulsion Gel Beads for the Encapsulation and Intragastric Floating Delivery of the Active Antioxidant from Tamarindus indica L.

Directory of Open Access Journals (Sweden)

Sitthiphong Soradech

2016-03-01

Full Text Available In this study, tamarind (Tamarindus indica L. seed extracts with potential antioxidant activity and toxicity to cancer cells were developed as functional foods and nutraceutical ingredients in the form of emulsion gel beads. Three extracts were obtained from ethanol and water: TSCH50, TSCH95 and TSCH. All extracts exhibited high potential for superoxide anion scavenging activity over the IC50 range < 5–11 µg/mL and had no toxic effects on normal cells, however, the water extract (TSCH was the most effective due to its free radical scavenging activity and toxicity in mitochondrial membranes of cancer cells. Next a study was designed to develop a new formulation for encapsulation and intragastric floating delivery of tamarind seed extract (TSCH using wax-incorporated emulsion gel beads, which were prepared using a modified ionotropic gelation technique. Tamarind seed extract at 1% (w/w was used as the active ingredient in all formulations. The effect of the types and amounts of wax on the encapsulation efficiency and percentage of the active release of alginate gel beads was also investigated. The results demonstrated that the incorporation of both waxes into the gel beads had an effect on the percentage of encapsulation efficiency (% and the percentage of the active ingredient release. Furthermore, the addition of water insoluble waxes (carnauba and bee wax significantly retarded the release of the active ingredient. The addition of both waxes had a slight effect on drug release behavior. Nevertheless, the increase in incorporated waxes in all formulations could sustain the percentage of active ingredient release. In conclusion, wax-incorporated emulsion gel beads using a modified ionotropic gelation technique could be applied for the intragastric floating delivery and controlled release of functional food and nutraceutical products for their antioxidant and anticancer capacity.

Comparing a motivational and a self-regulatory intervention to adopt an oral self-care regimen: a two-sequential randomized crossover trial.

Science.gov (United States)

Lhakhang, Pempa; Gholami, Maryam; Knoll, Nina; Schwarzer, Ralf

2015-01-01

A sequential intervention to facilitate the adoption and maintenance of dental flossing was conducted among 205 students in India, aged 18-26 years. Two experimental groups received different treatment sequences and were observed at three assessment points, 34 days apart. One group received first a motivational intervention (intention, outcome expectancies, and risk perception, followed by a self-regulatory intervention (planning, self-efficacy, and action control). The second group received the same intervention in the opposite order. Both intervention sequences yielded gains in terms of flossing, planning, self-efficacy, and action control. However, at Time 2, those who had received the self-regulatory intervention first, were superior to their counterparts who had received the motivational intervention first. At Time 3, differences vanished as everyone had then received both interventions. Thus, findings highlight the benefits of a self-regulatory compared to a mere motivational intervention.

Effect of Zeolite Treatment on the Blooming Behavior of Paraffin Wax in Natural Rubber Composites

Directory of Open Access Journals (Sweden)

Bryan B. Pajarito

2016-06-01

Full Text Available The blooming behavior of paraffin wax in natural rubber (NR composites was studied as function of zeolite treatment. Three types of zeolite treatment were treated as factors: acid activation using hydrochloric acid (HCl solution, ion exchange using tetradecyldimethyl amine (TDA chloride salt, and organic modification using glycerol monostearate (GMS. The zeolite was treated according to a 23 full factorial design of experiment. Attenuated total reflectance – Fourier transform infrared (ATR-FTIR spectroscopy was used to characterize the chemical structure of treated zeolite. Treated zeolite was applied as filler to NR composites deliberately compounded with high amount of paraff in wax. The amount of bloomed wax in surface of NR composite sheets was monitored with time at 50oC. Results show the bloom amount to be linear with the square root of time. NR composites reinforced with untreated, acid-activated, and ion-exchanged zeolite fillers indicate reduction in wax blooming as compared to unfilled NR. The bloom rate (slope and initial bloom (y-intercept were determined from the experimental plots. Analysis of variance (ANOVA shows the bloom rate to be signif icantly increased when zeolite fillers are treated with GMS. Meanwhile, initial bloom was significantly enhanced when zeolite fillers are treated with TDA chloride salt and GMS. The significant increase in bloom rate and initial bloom can be attributed to the softening of the NR matrix at high amounts of TDA chloride salt and GMS.

A comparison of the accuracy of patterns processed from an inlay casting wax, an auto-polymerized resin and a light-cured resin pattern material.

Science.gov (United States)

Rajagopal, Praveen; Chitre, Vidya; Aras, Meena A

2012-01-01

Traditionally, inlay casting waxes have been used to fabricate patterns for castings. Newer resin pattern materials offer greater rigidity and strength, allowing easier laboratory and intraoral adjustment without the fear of pattern damage. They also claim to possess a greater dimensional stability when compared to inlay wax. This study attempted to determine and compare the marginal accuracy of patterns fabricated from an inlay casting wax, an autopolymerized pattern resin and a light polymerized pattern resin on storage off the die for varying time intervals. Ten patterns each were fabricated from an inlay casting wax (GC Corp., Tokyo, Japan), an autopolymerized resin pattern material (Pattern resin, GC Corp, Tokyo, Japan) and a light-cured resin pattern material (Palavit GLC, Hereaus Kulzer GmbH, Germany). The completed patterns were stored off the die at room temperature. Marginal gaps were evaluated by reseating the patterns on their respective dies and observing it under a stereomicroscope at 1, 12, and 24 h intervals after pattern fabrication. The results revealed that the inlay wax showed a significantly greater marginal discrepancy at the 12 and 24 h intervals. The autopolymerized resin showed an initial (at 1 h) marginal discrepancy slightly greater than inlay wax, but showed a significantly less marginal gap (as compared to inlay wax) at the other two time intervals. The light-cured resin proved to be significantly more dimensionally stable, and showed minimal change during the storage period. The resin pattern materials studied, undergo a significantly less dimensional change than the inlay waxes on prolonged storage. They would possibly be a better alternative to inlay wax in situations requiring high precision or when delayed investment (more than 1 h) of patterns can be expected.

Scientific Opinion on the re-evaluation of carnauba wax (E 903) as a food additive

OpenAIRE

EFSA Panel on Food Additives and Nutrient Sources added to Food (ANS)

2012-01-01

The Panel on Food Additives and Nutrient Sources added to Food (ANS) delivers a scientific opinion re-evaluating the safety of carnauba wax (E 903). Carnauba wax (E 903) is authorised in the EU as food additive as glazing agent. It has been evaluated by the Scientific Committee on Food (SCF) and by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) who allocated an Acceptable Daily Intake (ADI) of 7 mg/kg bw/day. The SCF did not establish an ADI but considered the use of ca...

Leaf surface wax is a source of plant methane formation under UV radiation and in the presence of oxygen

DEFF Research Database (Denmark)

Bruhn, Dan; Mikkelsen, Teis Nørgaard; Rolsted, M. M. M.

2014-01-01

to this, we demonstrated that the UV radiation-induced CH4 emission is independent of leaf area index above unity. Further, we observed that the presence of O2 in the atmosphere was necessary for achieving the highest rates of CH4 emission. Methane formation from leaf surface wax is supposedly a two...... investigated the potential of the leaf surface wax itself as a source of UV radiationinduced leaf aerobic CH4 formation. Isolated leaf surface wax emitted CH4 at substantial rates in response to UV radiation. This discovery has implications for how the phenomenon should be scaled to global levels. In relation...

Immobilized Rhizopus oryzae lipase catalyzed synthesis of palm stearin and cetyl alcohol wax esters: Optimization by Response Surface Methodology

Directory of Open Access Journals (Sweden)

Gargouri Youssef

2011-06-01

Full Text Available Abstract Background Waxes are esters of long-chain fatty acids and long-chain alcohols. Their principal natural sources are animals (sperm whale oil and vegetables (jojoba which are expensive and not easily available. Wax esters synthesized by enzymatic transesterification, using palm stearin as raw material, can be considered as an alternative to natural ones. Results Palm stearin is a solid fraction obtained by fractionation of palm oil. Palm stearin was esterified with cetyl alcohol to produce a mixture of wax esters. A non-commercial immobilized lipase from Rhizopus oryzae was used as biocatalyst. Response surface methodology was employed to determine the effects of the temperature (30-50°C, the enzyme concentration (33.34-300 IU/mL, the alcohol/palm stearin molar ratio (3-7 mol/mol and the substrate concentration (0.06-0.34 g/mL on the conversion yield of palm stearin. Under optimal conditions (temperature, 30°C; enzyme concentration, 300 IU/mL; molar ratio 3 and substrate concentration 0.21 g/mL a high conversion yield of 98.52% was reached within a reaction time of 2 h. Conclusions Response surface methodology was successfully applied to determine the optimum operational conditions for synthesis of palm stearin based wax esters. This study may provide useful tools to develop economical and efficient processes for the synthesis of wax esters.

Composition of the epicuticular waxes coating the adaxial side of Phyllostachys aurea leaves: Identification of very-long-chain primary amides.

Science.gov (United States)

Racovita, Radu C; Jetter, Reinhard

2016-10-01

The present study presents comprehensive chemical analyses of cuticular wax mixtures of the bamboo Phyllostachys aurea. The epicuticular and intracuticular waxes were sampled selectively from the adaxial side of leaves on young and old plants and investigated by gas chromatography-mass spectrometry and flame ionization detection. The epi- and intracuticular layers on young and old leaves had wax loads ranging from 1.7 μg/cm(2) to 1.9 μg/cm(2). Typical very-long-chain aliphatic wax constituents were found with characteristic chain length patterns, including alkyl esters (primarily C48), alkanes (primarily C29), fatty acids (primarily C28 and C16), primary alcohols (primarily C28) and aldehydes (primarily C30). Alicyclic wax components were identified as tocopherols and triterpenoids, including substantial amounts of triterpenoid esters. Alkyl esters, alkanes, fatty acids and aldehydes were found in greater amounts in the epicuticular layer, while primary alcohols and most terpenoids accumulated more in the intracuticular wax. Alkyl esters occurred as mixtures of metamers, combining C20 alcohol with various acids into shorter ester homologs (C36C40), and a wide range of alcohols with C22 and C24 acids into longer esters (C42C52). Primary amides were identified, with a characteristic chain length profile peaking at C30. The amides were present exclusively in the epicuticular layer and thus at or near the surface, where they may affect plant-herbivore or plant-pathogen interactions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Ultrastructure of Wax-Producing Structures on the Integument of the Melaleuca Psyllid Boreioglycaspis melaleucae (Hemiptera: Psyllidae), with Honeydew Excretion Behavior in Males and Females

Science.gov (United States)

Ammar, El-Desouky; Hentz, Matthew; Hall, David G.; Shatters, Robert G.

2015-01-01

The melaleuca psyllid, Boreioglycaspis melaleucae (Hemiptera: Psyllidae), was introduced to Florida as a biological control agent against Melaleuca quinquenervia, an invasive evergreen tree that has invaded large areas of Florida Everglades. Colonies of B. melaleucae nymphs are normally covered by white waxy secretions, and nymphs of various instars produce long bundles of white waxy filaments extending laterally and posteriorly from their abdomen. Scanning electron microscopy of ‘naturally waxed’ and ‘dewaxed’ nymphs (cleaned from wax) revealed two types of wax pore plates located dorsally and laterally on the integument of posterior abdominal segments starting with the 4th segment. Type-1 wax pore plates, with raised rim, peripheral groove, slits and pits, produce long ribbons and filaments of waxy secretions that are wound together forming long wax bundles, whereas type-2 wax pore plates, with slits only, produce shorter wax curls. Additionally, in both nymphs and adult females, the circumanal ring contained ornate rows of wax pores that produce wax filaments covering their honeydew excretions. Video recordings with stereomicroscopy showed that adult females produce whitish honeydew balls, powerfully propelled away from their body, probably to get these sticky excretions away from their eggs and newly hatched nymphs. Adult males, however, produce clear droplets of honeydew immediately behind them, simply by bending the posterior end of the abdomen downward. The possible role(s) of waxy secretions by nymphs and adults of B. melaleucae in reducing contamination of their colonies with honeydew, among other possibilities, are discussed. PMID:25793934

In Vitro Implant Impression Accuracy Using a New Photopolymerizing SDR Splinting Material.

Science.gov (United States)

Di Fiore, Adolfo; Meneghello, Roberto; Savio, Gianpaolo; Sivolella, Stefano; Katsoulis, Joannis; Stellini, Edoardo

2015-10-01

The study aims to evaluate three-dimensionally (3D) the accuracy of implant impressions using a new resin splinting material, "Smart Dentin Replacement" (SDR). A titanium model of an edentulous mandible with six implant analogues was used as a master model and its dimensions measured with a coordinate measuring machine. Before the total 60 impressions were taken (open tray, screw-retained abutments, vinyl polysiloxane), they were divided in four groups: A (test): copings pick-up splinted with dental floss and fotopolymerizing SDR; B (test): see A, additionally sectioned and splinted again with SDR; C (control): copings pick-up splinted with dental floss and autopolymerizing Duralay® (Reliance Dental Mfg. Co., Alsip, IL, USA) acrylic resin; and D (control): see C, additionally sectioned and splinted again with Duralay. The impressions were measured directly with an optomechanical coordinate measuring machine and analyzed with a computer-aided design (CAD) geometric modeling software. The Wilcoxon matched-pair signed-rank test was used to compare groups. While there was no difference (p = .430) between the mean 3D deviations of the test groups A (17.5 μm) and B (17.4 μm), they both showed statistically significant differences (p impression techniques for edentulous jaws with multiple implants are highly accurate using the new fotopolymerizing splinting material SDR. Sectioning and rejoining of the SDR splinting had no impact on the impression accuracy. © 2015 Wiley Periodicals, Inc.

Army Guide to Deployment Health: Health Threat Information and Countermeasures

Science.gov (United States)

2012-01-01

cream, and lotion (for relief of athlete’s foot and jock itch). ` Toothbrushes (2) with vented cover, fluoridated toothpaste, dental floss. ` Yeast...some plants have thorns, stinging hairs, or toxic resins that may puncture the skin or cause skin irritation, rashes or infections. ` discourage...Brush twice a day with fluoride toothpaste. In difficult tactical environments brush or wipe teeth with a cloth at least once a day. ` You can brush

Evolutionary Conserved Function of Barley and Arabidopsis 3-KETOACYL-CoA SYNTHASES in Providing Wax Signals for Germination of Powdery Mildew Fungi1[C][W

Science.gov (United States)

Weidenbach, Denise; Jansen, Marcus; Franke, Rochus B.; Hensel, Goetz; Weissgerber, Wiebke; Ulferts, Sylvia; Jansen, Irina; Schreiber, Lukas; Korzun, Viktor; Pontzen, Rolf; Kumlehn, Jochen; Pillen, Klaus; Schaffrath, Ulrich

2014-01-01

For plant pathogenic fungi, such as powdery mildews, that survive only on a limited number of host plant species, it is a matter of vital importance that their spores sense that they landed on the right spot to initiate germination as quickly as possible. We investigated a barley (Hordeum vulgare) mutant with reduced epicuticular leaf waxes on which spores of adapted and nonadapted powdery mildew fungi showed reduced germination. The barley gene responsible for the mutant wax phenotype was cloned in a forward genetic screen and identified to encode a 3-KETOACYL-CoA SYNTHASE (HvKCS6), a protein participating in fatty acid elongation and required for synthesis of epicuticular waxes. Gas chromatography-mass spectrometry analysis revealed that the mutant has significantly fewer aliphatic wax constituents with a chain length above C-24. Complementation of the mutant restored wild-type wax and overcame germination penalty, indicating that wax constituents less present on the mutant are a crucial clue for spore germination. Investigation of Arabidopsis (Arabidopsis thaliana) transgenic plants with sense silencing of Arabidopsis REQUIRED FOR CUTICULAR WAX PRODUCTION1, the HvKCS6 ortholog, revealed the same germination phenotype against adapted and nonadapted powdery mildew fungi. Our findings hint to an evolutionary conserved mechanism for sensing of plant surfaces among distantly related powdery mildews that is based on KCS6-derived wax components. Perception of such a signal must have been evolved before the monocot-dicot split took place approximately 150 million years ago. PMID:25201879

Effect of maleic hydrazide and waxing on quality and shelf life of papaya (carica papaya L.) fruits

International Nuclear Information System (INIS)

Abu-Goukh, A. A.; Shattir, A. E.

2012-01-01

The effect of post harvest treatment of maleic hydrazide (MH) with and with out waxing on the quality and shelf-life of Baladi and Ekostika I papaya fruits at 18 ±1°C and 85%-90% relative humidity was evaluated. Maleic hydrazide at 250 and 500 ppm significantly delayed fruit ripening by two and three days in both papaya cultivars, respectively, compared with untreated fruits. The higher the concentration, the more was the delay in fruit ripening. The results also showed that waxing addition to MH resulted in a delay of two more days in fruit ripening that treatment with MH alone. The effect of MH and waxing treatments in delaying papaya fruits ripening was manifested in retarded respiratory climacteric, reduced weight loss and delayed fruit softening and increase in total soluble solids and ascorbic acid content.(Author)

Fuel Pellets from Wheat Straw: The Effect of Lignin Glass Transition and Surface Waxes on Pelletizing Properties

DEFF Research Database (Denmark)

Stelte, Wolfgang; Clemons, Craig; Holm, Jens K.

2012-01-01

and a high concentration of hydrophobic waxes on its outer surface that may limit the pellet strength. The present work studies the impact of the lignin glass transition on the pelletizing properties of wheat straw. Furthermore, the effect of surface waxes on the pelletizing process and pellet strength...... are investigated by comparing wheat straw before and after organic solvent extraction. The lignin glass transition temperature for wheat straw and extracted wheat straw is determined by dynamic mechanical thermal analysis. At a moisture content of 8%, transitions are identified at 53°C and 63°C, respectively....... Pellets are pressed from wheat straw and straw where the waxes have been extracted from. Two pelletizing temperatures were chosen—one below and one above the glass transition temperature of lignin. The pellets compression strength, density, and fracture surface were compared to each other. Pellets pressed...

Control of the wax moth Galleria mellonella L. (Lepidoptera: Pyralidae by the male sterile technique (MST

Directory of Open Access Journals (Sweden)

Jafari Reza

2010-01-01

Full Text Available In this study we examined the control of wax moth using the male sterile technique (MST with gamma-rays. To determine the safe and effective dosage of gamma-rays capable of sterilizing male pupae of the wax moth, male pupae were exposed to increasing single doses of gamma-rays (250, 300, 350 and 400 Gy. The release ratio of sterile to normal males was also studied in a similar experiment. Treatments included sterile males, normal males and virgin females at the following ratios: 1:1:1, 2:1:1, 3:1:1, 4:1:1 and 5:1:1. Possible parthenogenetic reproduction of this pest was also examined. The results showed that 350 Gy was the most effective dose capable of sterilizing the male pupae of the wax moth. The best release ratio was established at four sterile males, one normal male for each normal female (4:1:1. Also females were incapable of producing offspring without males.

Investigation of Carnuba Wax as Matrix in the Formulation of Solid ...

African Journals Online (AJOL)

This study was carried out to investigate the drug entrapment efficiency, release potential and drug release mechanisms of solid lipid microparticles (SLMs) prepared with different concentrations of two non ionic surfactants using carnauba wax as the lipid matrix. SLMs were prepared by melt dispersion technique, whereby ...

Environmental controls on the 2H/1H values of terrestrial leaf waxes in the eastern Canadian Arctic

Science.gov (United States)

Shanahan, Timothy M.; Hughen, Konrad A.; Ampel, Linda; Sauer, Peter E.; Fornace, Kyrstin

2013-10-01

The hydrogen isotope composition of plant waxes preserved in lacustrine sediments is a potentially valuable tool for reconstructing paleoenvironmental changes in the Arctic. However, in contrast to the mid- and low-latitudes, significantly less effort has been directed towards understanding the factors controlling D/H fractionation in high latitude plant waxes and the impact of these processes on the interpretation of sedimentary leaf wax δD records. To better understand these processes, we examined the D/H ratios of long chain fatty acids in lake surface sediments spanning a temperature and precipitation gradient on Baffin Island in the eastern Canadian Arctic. D/H ratios of plant waxes increase with increasing temperature and aridity, with values ranging from -240‰ to -160‰ over the study area. Apparent fractionation factors between n-alkanoic acids in Arctic lake sediments and precipitation(εFA-ppt) are less negative than those of mid-latitude lakes and modern plants by 25‰ to 65‰, consistent with n-alkane data from modern Arctic plants (Yang et al., 2011). Furthermore, εFA-ppt values from Arctic lakes become systematically more positive with increasing evaporation, in contrast to mid-latitude sites, which show little to no change in fractionation with aridity. These data are consistent with enhanced water loss and isotope fractionation at higher latitude in the Arctic summer, when continuous sunlight supports increased daily photosynthesis. The dominant control on δDFA variations on Baffin Island is temperature. However, changing εFA-ppt result in steeper δDFA-temperature relationships than observed for modern precipitation. The application of this δDFA-based paleotemperature calibration to existing δDFA records from Baffin Island produces much more realistic changes in late Holocene temperature and highlights the importance of these effects in influencing the interpretation of Arctic δDFA records. A better understanding of the controls on

In vitro and In vivo Characterisation of Piroxicam-Loaded Dika Wax ...

African Journals Online (AJOL)

Purpose: To formulate piroxicam-loaded lipospheres and evaluate their in vitro and in vivo properties. Method: Piroxicam-loaded lipospheres were prepared by hot homogenization technique using dika wax and Phospholipon® 90G (1:1, 1:2 and 2:1) as the lipid matrix. Characterisation, based on particle size

Composition of secondary alcohols, ketones, alkanediols, and ketols in Arabidopsis thaliana cuticular waxes

Science.gov (United States)

Wen, Miao; Jetter, Reinhard

2009-01-01

Arabidopsis wax components containing secondary functional groups were examined (i) to test the biosynthetic relationship between secondary alcohols and ketols and (ii) to determine the regiospecificity and substrate preference of the enzyme involved in ketol biosynthesis. The stem wax of Arabidopsis wild type contained homologous series of C27 to C31 secondary alcohols (2.4 μg cm−2) and C28 to C30 ketones (6.0 μg cm−2) dominated by C29 homologues. In addition, compound classes containing two secondary functional groups were identified as C29 diols (∼0.05 μg cm−2) and ketols (∼0.16 μg cm−2). All four compound classes showed characteristic isomer distributions, with functional groups located between C-14 and C-16. In the mah1 mutant stem wax, diols and ketols could not be detected, while the amounts of secondary alcohols and ketones were drastically reduced. In two MAH1-overexpressing lines, equal amounts of C29 and C31 secondary alcohols were detected. Based on the comparison of homologue and isomer compositions between the different genotypes, it can be concluded that biosynthetic pathways lead from alkanes to secondary alcohols, and via ketones or diols to ketols. It seems plausible that MAH1 is the hydroxylase enzyme involved in all these conversions in Arabidopsis thaliana. PMID:19346242

Cognitive impairment in older adults and oral health considerations: treatment and management.

Science.gov (United States)

Brennan, Leonard J; Strauss, Jason

2014-10-01

Worldwide incidences of degenerative cognitive diseases are increasing as the population ages. This decline in mental function frequently causes behavioral changes that directly affect oral health. The loss of interest and ability to complete the simple tasks of brushing and flossing can cause a rapid development of hard and soft tissue diseases that result in decreased function and increased dental pain. The challenge for the dental community is to understand and to identify the early signs of cognitive dysfunction so as to develop a rational treatment strategy that allows patients to comfortably maintain their teeth for as long as possible. Copyright © 2014 Elsevier Inc. All rights reserved.

Antibacterial and antifungal effect of high pH and paraffin wax ...

African Journals Online (AJOL)

The antibacterial and antifungal effects of high pH (9, 10) and paraffin wax were determined. Determination of antibacterial and antifungal activity of the combined treatments was achieved by aerobic mesophilic count of bacteria and fungi on the surface of the tomatoes, peppers and oranges using serial dilution and pour ...

A comparison of epicuticular wax of Pinus sylvestris needles from three sites in Ireland

International Nuclear Information System (INIS)

Donnelly, A.; Dowding, P.

1994-01-01

Three forest stands of Pinus sylvestris were chosen for comparison in Ireland. Needles from three year classes were collected. Cuticular transpiration curves showed that the rate of water loss from 1-year-old needles was faster than either 2-year-old or current-year needles at all sites. The amount of epicuticular wax extracted was similar to that reported in the literature. Needle wettability increased with needle age. Amorphous wax coverage was estimated using scanning electron microscopy (SEM) and was found to increase with needle age. Algal cells were noted on needles of all ages at one site and appeared to affect transpiration and microroughness. The presence of fungal hyphae was also noted. (orig.)

Study of Plant Waxes Using Low Temperature Method for ESEM

Czech Academy of Sciences Publication Activity Database

Neděla, Vilém; Tihlaříková, Eva; Schiebertová, P.; Zajícová, I.; Schwarzerová, K.

2016-01-01

Roč. 22, S3 (2016), s. 1180-1181 ISSN 1431-9276 R&D Projects: GA ČR(CZ) GA14-22777S; GA MŠk ED0017/01/01 Grant - others:GA MŠk(CZ) LO1211 Institutional support: RVO:68081731 Keywords : ESEM * plant waxes * low temperature method Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 1.891, year: 2016

75 FR 33169 - Dental Devices: Classification of Dental Amalgam, Reclassification of Dental Mercury, Designation...

Science.gov (United States)

2010-06-11

.... FDA-2008-N-0163] (formerly Docket No. 2001N-0067) RIN 0910-AG21 Dental Devices: Classification of Dental Amalgam, Reclassification of Dental Mercury, Designation of Special Controls for Dental Amalgam... the Federal Register of August 4, 2009 (74 FR 38686) which classified dental amalgam as a class II...

"Wax bloom" on beeswax cultural heritage objects: exploring the causes of the phenomenon

Czech Academy of Sciences Publication Activity Database

Bartl, B.; Kobera, Libor; Drábková, K.; Ďurovič, M.; Brus, Jiří

2015-01-01

Roč. 53, č. 7 (2015), s. 509-513 ISSN 0749-1581 Institutional support: RVO:61389013 Keywords : 13-C NMR * wax bloom * efflorescence Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.226, year: 2015

Phase Change Material Trade Study: A Comparison Between Wax and Water for Manned Spacecraft

Science.gov (United States)

Quinn, Gregory; Hodgson, Ed; Stephan, Ryan A,

2011-01-01

Phase change material heat sinks have been recognized as an important tool in optimizing thermal control systems for space exploration vehicles and habitats that must deal with widely varying thermal loads and environments. In order to better focus technology investment in this arena, NASA has supported a trade study with the objective of identifying where the best potential pay-off can be found among identified aqueous and paraffin wax phase change materials and phase change material heat sink design approaches. The study used a representative exploration mission with well understood parameters to support the trade. Additional sensitivity studies were performed to ensure the applicability of study results across varying systems and destinations. Results from the study indicate that replacing a wax PCM heat sink with a water ice PCM heat sink has the potential to decrease the equivalent system mass of the mission s vehicle through a combination of a smaller heat sink and a slight 5% increase in radiator size or the addition of a lightweight heat pump. An evaluation of existing and emerging PCM heat sink technologies indicates that further mass savings should be achievable through continued development of those technologies. The largest mass savings may be realized by eliminating the melting and freezing pressure of wax and water, respectively.

Designing maleic anhydride-{alpha}-olifin copolymeric combs as wax crystal growth nucleators

Energy Technology Data Exchange (ETDEWEB)

Soni, Hemant P. [Department of Chemistry, Faculty of Science, The Maharaja Sayajirao University of Baroda, Vadodara-390 002 (India); Kiranbala; Bharambe, D.P. [Department of Applied Chemistry, Faculty of Technology and Engineering, The Maharaja Sayajirao University of Baroda, Vadodara-390 001 (India); Agrawal, K.S. [Department of Petrochemical Technology, Polytechnic, The Maharaja Sayajirao University of Baroda, Vadodara-390 002 (India); Nagar, A. [MH ASSET, ONGC, Mumbai (India)

2010-09-15

Modification of the wax crystal habit is of great practical interest during transportation and processing of crude oil at low temperature. Various pour point depressant (PPD) additives can facilitate this modification by different mechanisms. Comb shaped polymer additives are known to depress the pour point of crude oil by providing different nucleation sites for the precipitation of wax. This paper describes performance based design, synthesis, characterization and evaluation of comb shaped polymeric diesters. Copolymers of maleic anhydride with different unsaturated C{sub 22} esters were synthesized and copolymers then reacted with two unsaturated fatty alcohols. All products were characterized by Fourier Transform Infra Red (FTIR) spectroscopy and Gel Permeation Chromatography (GPC). Rheological properties of crude (with and without additive) were studied by Advance Rheometer AR-500. In this study the additive based on oleic acid was evaluated as good PPD and rheology modifier. (author)

SAXS-WAXS studies of the low-resolution structure in solution of xylose/glucose isomerase from Streptomyces rubiginosus

Science.gov (United States)

Kozak, Maciej; Taube, Michał

2009-10-01

The structure and conformation of molecule of xylose/glucose isomerase from Streptomyces rubiginosus in solution (at pH 6 and 7.6; with and without the substrate) has been studied by small- and wide-angle scattering of synchrotron radiation (SAXS-WAXS). On the basis of the SAXS-WAXS data, the low-resolution structure in solution has been reconstructed using ab inito methods. A comparison of the models of glucose isomerase shows only small differences between the model in solution and the crystal structure.

Dental Amalgam

Science.gov (United States)

... Products and Medical Procedures Dental Devices Dental Amalgam Dental Amalgam Share Tweet Linkedin Pin it More sharing options Linkedin Pin it Email Print Dental amalgam is a dental filling material which is ...

A comparative evaluation of microleakage of restorations using silorane-based dental composite and methacrylate-based dental composites in Class II cavities: An in vitro study

Directory of Open Access Journals (Sweden)

Jambai Sampath Kumar Sivakumar

2016-01-01

Full Text Available Aim: The aim of this in vitro study was to evaluate and compare the microleakage of restorations using low shrinkage silorane-based dental composite and methacrylate-based dental composites in Class II cavity at the occlusal and gingival margins. Materials and Methods: Sixty mandibular molars were collected and divided into three experimental groups and one negative control group. Class II slot cavity was prepared on the mesial surface. Experimental groups were restored with Group I: silorane-based microhybrid composite, Group II: methacrylate-based nanohybrid composite, and Group III: Methacrylate-based microhybrid composite, respectively. Group IV: negative control. The samples were thermocycled, root apices were sealed with sticky wax and coated with nail varnish except 1 mm around the restoration. This was followed by immersion in 2% Rhodamine-B dye solution under vacuum at room temperature for 24 h. Then, the samples were sectioned longitudinally in the mesiodistal direction and evaluated under stereomicroscope ×40 magnification. Scoring was done according to the depth of dye penetration in to the cavity. Statistical analysis of the data was done. Results: The results were that no statistically significant difference in the microleakage at the occlusal margin for all the restorative materials, whereas at the gingival margin, silorane-based microhybrid composite showed less microleakage than the methacrylate-based nano- and micro-hybrid composites. Conclusion: In general, silorane-based microhybrid composite had less microleakage among the other materials used in this in vitro study.

A case of butane hash oil (marijuana wax)-induced psychosis.

Science.gov (United States)

Keller, Corey J; Chen, Evan C; Brodsky, Kimberly; Yoon, Jong H

2016-01-01

Marijuana is one of the most widely used controlled substances in the United States. Despite extensive research on smoked marijuana, little is known regarding the potential psychotropic effects of marijuana "wax," a high-potency form of marijuana that is gaining in popularity. The authors present a case of "Mr. B," a 34-year-old veteran who presented with profound psychosis in the setting of recent initiation of heavy, daily marijuana wax use. He exhibited incoherent speech and odd behaviors and appeared to be in a dream-like state with perseverating thoughts about his combat experience. His condition persisted despite treatment with risperidone 4 mg twice a day (BID), but improved dramatically on day 8 of hospitalization with the return of baseline mental function. Following discharge, Mr. B discontinued all marijuana use and did not exhibit the return of any psychotic symptoms. This study highlights the need for future research regarding the potential medical and psychiatric effects of new, high-potency forms of marijuana. Could cannabis have a dose-dependent impact on psychosis? What other potential psychiatric effects could emerge heretofore unseen in lower potency formulations? Given the recent legalization of marijuana, these questions merit timely exploration.

Anti-botrytis activity in epicuticular waxes of young grape berries of Vitis vinifera (Pinot noir

Directory of Open Access Journals (Sweden)

Pascal Comménil

1996-03-01

The evidence of a substance which exhibits a strong inhibition on the conidial germination of Botrytis cinerea was made after epicuticular waxes chromatographic analysis and biological tests. This compound, characterized by a Rf (0,2 closely related to the Rf of the primary alcohols, was present in the wax extracts originated from bloom and immature grape berries stages and it was absent in the extracts issued to the mature grape berries. The concentration of the conidial germination inhibitor was markedly different between the sensible (S792 and tolerant (T7613 cultivars of Pinot vineyards. Also this antifungal product would be considereted as an hypothetical resistance marked against Botrytis cinerea.

Weaker dental enamel explains dental decay.

Science.gov (United States)

Vieira, Alexandre R; Gibson, Carolyn W; Deeley, Kathleen; Xue, Hui; Li, Yong

2015-01-01

Dental caries continues to be the most prevalent bacteria-mediated non-contagious disease of humankind. Dental professionals assert the disease can be explained by poor oral hygiene and a diet rich in sugars but this does not account for caries free individuals exposed to the same risk factors. In order to test the hypothesis that amount of amelogenin during enamel development can influence caries susceptibility, we generated multiple strains of mice with varying levels of available amelogenin during dental development. Mechanical tests showed that dental enamel developed with less amelogenin is "weaker" while the dental enamel of animals over-expressing amelogenin appears to be more resistant to acid dissolution.

Physical characteristics of tetrahydroxy and acylated derivatives of jojoba liquid wax

Science.gov (United States)

Jojoba liquid wax is a mixture of esters of long chain fatty acids and fatty alcohols, mainly (C38:2-C46:2). The oil exhibits excellent emolliency on the skin and therefore is a component in many personal care cosmetic formulations. The virgin oil is a component of the seed of the Jojoba (Simmondsia...

5-Fluorouracil:carnauba wax microspheres for chemoembolization: an in vitro evaluation.

Science.gov (United States)

Benita, S; Zouai, O; Benoit, J P

1986-09-01

5-Fluorouracil:carnauba wax microspheres were prepared using a meltable dispersion process with the aid of a surfactant as a wetting agent. It was noted that only hydrophilic surfactants were able to wet the 5-fluorouracil and substantially increased its content in the microspheres. No marked effect was observed in the particle size distribution of the solid microspheres as a function of the nature of the surfactant. Increasing the stirring rate in the preparation process decreased, first, the mean droplet size of the emulsified melted dispersion in the vehicle during the heating process, and, consequently, the mean particle size of the solidified microspheres during the cooling process. 5-Fluorouracil cumulative release from the microspheres followed first-order kinetics, as shown by nonlinear regression analysis. Although the kinetic results were not indicative of the true release mechanism from a single microsphere, it was believed that 5-fluorouracil release from the microspheres was probably governed by a dissolution process, rather than by a leaching process through the carnauba wax microspheres.

Paraffin wax passivation layer improvements in electrical characteristics of bottom gate amorphous indium–gallium–zinc oxide thin-film transistors

International Nuclear Information System (INIS)

Chang, Geng-Wei; Chang, Ting-Chang; Syu, Yong-En; Tsai, Tsung-Ming; Chang, Kuan-Chang; Tu, Chun-Hao; Jian, Fu-Yen; Hung, Ya-Chi; Tai, Ya-Hsiang

2011-01-01

In this research, paraffin wax is employed as the passivation layer of the bottom gate amorphous indium–gallium–zinc oxide thin-film transistors (a-IGZO TFTs), and it is formed by sol–gel process in the atmosphere. The high yield and low cost passivation layer of sol–gel process technology has attracted much attention for current flat-panel-display manufacturing. Comparing with passivation-free a-IGZO TFTs, passivated devices exhibit a superior stability against positive gate bias stress in different ambient gas, demonstrating that paraffin wax shows gas-resisting characteristics for a-IGZO TFTs application. Furthermore, light-induced stretch-out phenomenon for paraffin wax passivated device is suppressed. This superior stability of the passivated device was attributed to the reduced total density of states (DOS) including the interfacial and semiconductor bulk trap densities.

Perceptions of oral health, preventive care, and care-seeking behaviors among rural adolescents.

Science.gov (United States)

Dodd, Virginia J; Logan, Henrietta; Brown, Cameron D; Calderon, Angela; Catalanotto, Frank

2014-12-01

An asymmetrical oral disease burden is endured by certain population subgroups, particularly children and adolescents. Reducing oral health disparities requires understanding multiple oral health perspectives, including those of adolescents. This qualitative study explores oral health perceptions and dental care behaviors among rural adolescents. Semistructured individual interviews with 100 rural, minority, low socioeconomic status adolescents revealed their current perceptions of oral health and dental care access. Respondents age ranged from 12 to 18 years. The sample was 80% black and 52% male. Perceived threat from dental disease was low. Adolescents perceived regular brushing and flossing as superseding the need for preventive care. Esthetic reasons were most often cited as reasons to seek dental care. Difficulties accessing dental care include finances, transportation, fear, issues with Medicaid coverage and parental responsibility. In general, adolescents and their parents are in need of information regarding the importance of preventive dental care. Findings illuminate barriers to dental care faced by low-income rural adolescents and counter public perceptions of government-sponsored dental care programs as being "free" or without cost. The importance of improved oral health knowledge, better access to care, and school-based dental care is discussed. © 2014, American School Health Association.

The Effect of Paraffin Wax to Properties of Radiation Vulcanization Natural Rubber Latex (RVNRL)

International Nuclear Information System (INIS)

Mohd Noorwadi Mat Lazim; Sofian Ibrahim; Muhammad Saiful Omar

2015-01-01

Dipping factories often encounter a serious problem with high tackiness of the finish products during storage. The tackiness effect can be lead to rejection of products. This tackiness effect of natural (NR) rubber film originates in the free rubber chain ends at the surface of the film. The tackiness is not depends on the degree of crosslinking (vulcanization), since radiation itself unable to reduce the tackiness effect. The RVNRL requires addition of additive or anti-tack agent into formulation to reduce tackiness effect. In this experiment, paraffin wax manufactured by Emulco Sdn Bhd under the trade name Aquawax 48 was added into RVNRL formulation as anti-tack and the effect of paraffin wax to physical and mechanical properties of RVNRL was study. (author)

Lifestyle Change Plus Dental Care (LCDC) program improves knowledge, attitude, and practice (KAP) toward oral health and diabetes mellitus among the elderly with type 2 diabetes.

Science.gov (United States)

Saengtipbovorn, Saruta; Taneepanichskul, Surasak

2015-03-01

Currently, there is an increased prevalence of diabetes mellitus among the elderly. Chronic inflammation from diabetes mellitus effects glycemic control and increases risk of diabetes complications. To assess the effectiveness of a Lifestyle Change plus Dental Care (LCDC) program by improved knowledge, attitude, and practice (KAP) toward oral health and diabetes mellitus among the elderly with type 2 diabetes. A quasi-experimental study was conducted in two Health Centers (HC 54 intervention and HC 59 control) between October 2013 and April 2014. Sixty-six diabetic patients per health center were recruited. At baseline, the intervention group attended a 20-minute lifestyle and oral health education program, individual lifestyle counseling using motivational interviewing, application of self-regulation manual, and individual oral hygiene instruction. At 3-month follow-up, the intervention group received individual lifestyle counseling and oral hygiene instruction. The intervention group received booster education every visit by viewing a 15-minute educational video. The control group received the routine program. Participants were assessed at baseline, 3-month, and 6-month follow-up for knowledge, attitude, and practice (KAP) toward oral health and diabetes mellitus. Data was analyzed by using descriptive statistic, Chi-square test, Fisher's exact test, and repeated measure ANOVA. After the 6-month follow-up, repeated measure ANOVA analysis showed that participants in the intervention group had significantly higher knowledge and attitude toward oral health and diabetes mellitus. The participants in the intervention group were more likely to exercise, modify diet, have foot examinations, always wear covered shoes, participate in self-feet screening, use dental floss, and use inter-proximal brush than the control group with statistically significant differences. The combination of lifestyle change and dental care in one program improved knowledge, attitude

Biodiesel from Jojoba oil-wax: Transesterification with methanol and properties as a fuel

Energy Technology Data Exchange (ETDEWEB)

Canoira, Laureano; Alcantara, Ramon; Garcia-Martinez, Jesus; Carrasco, Jesus [Department of Chemical Engineering and Fuels, School of Mines, Polytechnic University of Madrid, Rios Rosas 21, 28003-Madrid (Spain)

2006-01-15

The Jojoba oil-wax is extracted from the seeds of the Jojoba (Simmondsia chinensis Link Schneider), a perennial shrub that grows in semi desert areas in some parts of the world. The main uses of Jojoba oil-wax are in the cosmetics and pharmaceutical industry, but new uses could arise related to the search of new energetic crops. This paper summarizes a process to convert the Jojoba oil-wax to biodiesel by transesterification with methanol, catalysed with sodium methoxide (1wt% of the oil). The transesterification reaction has been carried out in an autoclave at 60 deg C, with a molar ratio methanol/oil 7.5:1, and vigorous stirring (600rpm), reaching a quantitative conversion of the oil after 4h. The separation of the fatty acid methyl esters (the fraction rich in FAME, 79% FAME mixture; 21% fatty alcohols; 51% of methyl cis-11-eicosenoate) from the fatty alcohols rich fraction (72% fatty alcohols; 28% FAME mixture; 26% of cis-11-eicosen-1-ol, 36% of cis-13-docosen-1-ol) has been accomplished in a single crystallization step at low temperature (-18 deg C) from low boiling point petroleum ether. The fraction rich in FAME has a density (at 15 deg C), a kinematic viscosity (at 40 deg C), a cold filter plugging point and a high calorific value in the range of the European standard for biodiesel (EN 14214)

[Effect of heat treatment on the structure of a Cu-Zn-Al-Ni system dental alloy].

Science.gov (United States)

Guastaldi, A C; Adorno, A T; Beatrice, C R; Mondelli, J; Ishikiriama, A; Lacefield, W

1990-01-01

This article characterizes the structural phases present in the copper-based metallic alloy system "Cu-Zn-Al-Ni" developed for dental use, and relates those phases to other properties. The characterization was obtained after casting (using the lost wax process), and after heat treatment. In order to obtain better corrosion resistance by changing the microstructure, the castings were submitted to 30, 45 and 60 minutes of heat treatment at the following temperatures: 750 degrees C, 800 degrees C, and 850 degrees C. The various phases were analyzed using X-ray diffraction and scanning electron microscopy (SEM). The results after heat treatment showed a phase (probably Cu3Al), that could be responsible for the improvement in the alloy's resistance to corrosion as compared to the as-cast structure.

Printed wax masks for 254 nm deep-UV pattering of PMMA-based microfluidics

KAUST Repository

Fan, Yiqiang; Liu, Yang; Li, Huawei; Foulds, Ian G.

2012-01-01

This paper reports a new technique for masking deep-UV exposure of poly(methyl methacrylate) (PMMA) using a printed wax mask. This technique provides an inexpensive and bulk fabrication method for PMMA structures. The technique involves the direct

Dental Fear and Delayed Dental Care in Appalachia-West Virginia.

Science.gov (United States)

Wiener, R Constance

2015-08-01

The people of Appalachia-West Virginia are culturally unique and are known to have oral health disparities. The purpose of this study was to evaluate dental fear in relation to delayed dental care as a factor influencing oral health behaviors within this culture. A cross sectional study design was used. Participants were urgent care patients in a university dental clinic. The sample included 140 adults over age 18 years. The Dental Fear Survey was used to determine dental fear level. Self-report of delayed dental care was provided by the participants. The Dental Fear Survey was dichotomized at score 33, with higher scores indicating dental fear. The prevalence of dental fear was 47.1% (n=66). There was a significant association of dental fear and dental delay. The unadjusted odds ratio was 2.87 (95% CI: 1.17, 7.04; p=0.021). The adjusted odds ratio was 3.83 (95%CI: 1.14, 12.82; p=0.030), controlling for tobacco use, perceived oral health status, pain, and last dental visit. A difference in dental delay between men and women was not present in this sample. The only significant variable in delayed dental care was dental fear. In Appalachia-West Virginia, there remains a high level of dental fear, despite advances in dental care, techniques, and procedures. Copyright © 2015 The American Dental Hygienists’ Association.

Developing a flexible core Dental Public Health curriculum for predoctoral dental and dental hygiene schools.

Science.gov (United States)

Atchison, Kathryn; Mascarenhas, Ana Karina; Bhoopathi, Vinodh

2015-01-01

The curriculum for graduating dental and dental hygiene students must prepare them to contribute to the improvement or maintenance of health for individual patient's and the public's health. The objective is to describe the background for and the process used to develop a core Dental Public Health Curriculum for such students. The process used was to solicit and review existing dental public health curriculum in dental and dental hygiene schools; review curriculum for other health professionals; identify the themes needed to frame the curriculum; select usable materials and identify gaps in existing curricular materials; and develop appropriate curriculum materials that would embody the competencies developed for undergraduate dental and dental hygiene education. Twenty-three topics were identified as embodying the eight competencies. Based on these topics, six courses, Principles of Dental Public Health, Evidence-Based Dentistry, Ethics and Dental Public Health, Dental Public Health Policy and Advocacy, Oral Health Promotion and Disease Prevention, and Oral Health Literacy and Dental Public Health, were prepared. Each course includes syllabus, PowerPoint presentations, student assignments and activities, instructor guide, and classroom discussion points. Depending on the hours available in the existing curriculum at the dental or hygiene school, lecture presentations and take home assignments/discussions may be used independently or in combination with presentations from other courses. In addition, individual discussions and activities may be used to integrate dental public health materials into other courses. A flexible curriculum is available at the AAPHD website to enable the incorporation of DPH topics into the curriculum. © 2015 American Association of Public Health Dentistry.

Evaluation of thermal stability of paraffin wax by differential scanning calorimetry; Avaliacao da estabilidade termica de parafina por calorimetria diferencial de varredura

Energy Technology Data Exchange (ETDEWEB)

Godinho, K.O.; Silva, A.G.P.; Holanda, J.N.F. [Universidade Estadual do Norte Fluminense (LAMAV/UENF), Campos dos Goytacazes, RJ (Brazil). Grupo de Materiais Ceramicos], Email: holanda@uenf.br

2010-07-01

Phase change materials for heat storage are used as passive solar energy storage materials, which can be impregnated into construction materials. In this work the thermal stability (heating/cooling cycle) of the paraffin wax was investigated using differential scanning calorimetry. The latent heat and fusion temperature were determined for the following thermal cycles: 0, 30, 180 and 360. The thermal stability for paraffin wax infiltrated in support of gypsum was also determined. The experimental results showed that the paraffin wax showed good thermal stability in the states pure and infiltrated for up to 360 thermal cycles. (author)

Cgl2 plays an essential role in cuticular wax biosynthesis in cabbage (Brassica oleracea L. var. capitata).

Science.gov (United States)

Liu, Dongming; Tang, Jun; Liu, Zezhou; Dong, Xin; Zhuang, Mu; Zhang, Yangyong; Lv, Honghao; Sun, Peitian; Liu, Yumei; Li, Zhansheng; Ye, Zhibiao; Fang, Zhiyuan; Yang, Limei

2017-11-28

The aerial parts of most land plants are covered with cuticular wax which is important for plants to avoid harmful factors. There is still no cloning study about wax synthesis gene of the alcohol-forming pathway in Brassica species. Scanning electron microscopy (SEM) showed that, compared with wild type (WT), wax crystal are severely reduced in both the adaxial and abaxial sides of cabbage (Brassica oleracea L. var. capitata L.) leaves from the LD10GL mutant. Genetic analysis results revealed that the glossy trait of LD10GL is controlled by a single recessive gene, and fine mapping results revealed that the target gene Cgl2 (Cabbage glossy 2) is located within a physical region of 170 kb on chromosome 1. Based on sequence analysis of the genes in the mapped region, the gene designated Bol013612 was speculated to be the candidate gene. Gene Bol013612 is homologous to Arabidopsis CER4, which encodes fatty acyl-coenzyme A reductase. Sequencing identified a single nucleotide substitution at an intron/exon boundary that results in an insertion of six nucleotides in the cDNA of Bol013612 in LD10GL. The phenotypic defect of LD10GL was confirmed by a functional complementation test with Arabidopsis mutant cer4. Our results indicated that wax crystals of cabbage mutant LD10GL are severely reduced and mutation of gene Bol013612 causes a glossy phenotype in the LD10GL mutant.

Laser micromachined wax-covered plastic paper as both sputter deposition shadow masks and deep-ultraviolet patterning masks for polymethylmethacrylate-based microfluidic systems

KAUST Repository

Fan, Yiqiang

2013-12-16

We report a technically innovative method of fabricating masks for both deep-ultraviolet (UV) patterning and metal sputtering on polymethylmethacrylate (PMMA) for microfluidic systems. We used a CO2 laser system to cut the required patterns on wax-covered plastic paper; the laser-patterned wax paper will either work as a mask for deep-UV patterning or as a mask for metal sputtering. A microfluidic device was also fabricated to demonstrate the feasibility of this method. The device has two layers: the first layer is a 1-mm thick PMMA substrate that was patterned by deep-UV exposure to create microchannels. The mask used in this process was the laser-cut wax paper. The second layer, also a 1-mm thick PMMA layer, was gold sputtered with patterned wax paper as the shadow mask. These two pieces of PMMA were then bonded to form microchannels with exposed electrodes. This process is a simple and rapid method for creating integrated microfluidic systems that do not require cleanroom facilities.

Economic impact of dental hygienists on solo dental practices.

Science.gov (United States)

Lazar, Vickie F; Guay, Albert H; Beazoglou, Tryfon J

2012-08-01

The fact that a significant percentage of dentists employ dental hygienists raises an important question: Are dental practices that utilize a dental hygienist structurally and operationally different from practices that do not? This article explores differences among dental practices that operate with and without dental hygienists. Using data from the American Dental Association's 2003 Survey of Dental Practice, a random sample survey of U.S. dentists, descriptive statistics were used to compare selected characteristics of solo general practitioners with and without dental hygienists. Multivariate regression analysis was used to estimate the effect of dental hygienists on the gross billings and net incomes of solo general practitioners. Differences in practice characteristics--such as hours spent in the practice and hours spent treating patients, wait time for a recall visit, number of operatories, square feet of office space, net income, and gross billings--were found between solo general practitioners who had dental hygienists and those who did not. Solo general practitioners with dental hygienists had higher gross billings. Higher gross billings would be expected, as would higher expenses. However, net incomes of those with dental hygienists were also higher. In contrast, the mean waiting time for a recall visit was higher among dentists who employed dental hygienists. Depending on personal preferences, availability of qualified personnel, etc., dentists who do not employ dental hygienists but have been contemplating that path may want to further research the benefits and opportunities that may be realized.

Conservação de goiabas tratadas com emulsões de cera de carnaúba Postharvest conservation of guavas through carnauba wax emulsion applications

Directory of Open Access Journals (Sweden)

Angelo Pedro Jacomino

2003-12-01

Full Text Available A goiaba é um fruto muito perecível. Assim, objetivou-se avaliar os efeitos de ceras à base de carnaúba na conservação pós-colheita de goiabas Pedro Sato sob condição ambiente. Utilizaram-se cinco ceras comerciais: Citrosol AK (18%, Citrosol M (10%, Fruit wax (18 a 21%, Meghwax ECF-100 (30% e Cleantex wax (18,5 a 20,5%, as quais foram aplicadas manualmente, na proporção de 0,15 a 0,20mL por fruta. Frutas sem aplicação de cera foram utilizadas como controle. O delineamento experimental foi inteiramente casualizado com 6 tratamentos, 4 repetições e 5 frutas por parcela. As goiabas foram caracterizadas imediatamente após a colheita e avaliadas aos 2, 4 e 6 dias após a aplicação dos tratamentos. As ceras exerceram pouca influência nos teores de sólidos solúveis totais, acidez total titulável e ácido ascórbico, porém, foram eficientes em retardar o amadurecimento, reduzir a perda de massa e a incidência de podridões. A cera Meghwax ECF-100 apresenta potencial para utilização em goiabas, porém há necessidade de ser avaliada em maior diluição, para evitar alterações indesejáveis.Guavas are very perishable fruits. Therefore, the objective of the present work was to evaluate the effects of several carnauba based waxes in the postharvest life of Pedro Sato guavas under room conditions. Five commercial waxes were used: Citrosol AK (18%, Citrosol M (10%, Fruit wax (18 a 21%, Meghwax ECF-100 (30% e Cleantex wax (18,5 a 20,5%. The waxes were applied manualy in the rate of 0.15 to 0.20mL of wax per fruit. Control fruits were not treated. The experiment was conducted in a completely randomized design with 6 treatments, 4 replicates per treatment and 5 fruits as experimental unit. Guavas were evaluated at harvest and at every 2 days until the 6th day after treatments. Waxing had little effect on total soluble solids, total titratable acidity and ascorbic acid contents. However, the waxes were efficient in delaying ripening

Calculation of the store house worker dose in a lost wax foundry using MCNP-4C.

Science.gov (United States)

Alegría, Natalia; Legarda, Fernando; Herranz, Margarita; Idoeta, Raquel

2005-01-01

Lost wax casting is an industrial process which permits the transmutation into metal of models made in wax. The wax model is covered with a silicaceous shell of the required thickness and once this shell is built the set is heated and wax melted. Liquid metal is then cast into the shell replacing the wax. When the metal is cool, the shell is broken away in order to recover the metallic piece. In this process zircon sands are used for the preparation of the silicaceous shell. These sands have varying concentrations of natural radionuclides: 238U, 232Th and 235U together with their progenics. The zircon sand is distributed in bags of 50 kg, and 30 bags are on a pallet, weighing 1,500 kg. The pallets with the bags have dimensions 80 cm x 120 cm x 80 cm, and constitute the radiation source in this case. The only pathway of exposure to workers in the store house is external radiation. In this case there is no dust because the bags are closed and covered by plastic, the store house has a good ventilation rate and so radon accumulation is not possible. The workers do not touch with their hands the bags and consequently skin contamination will not take place. In this study all situations of external irradiation to the workers have been considered; transportation of the pallets from vehicle to store house, lifting the pallets to the shelf, resting of the stock on the shelf, getting down the pallets, and carrying the pallets to production area. Using MCNP-4C exposure situations have been simulated, considering that the source has a homogeneous composition, the minimum stock in the store house is constituted by 7 pallets, and the several distances between pallets and workers when they are at work. The photons flux obtained by MCNP-4C is multiplied by the conversion factor of Flux to Kerma for air by conversion factor to Effective Dose by Kerma unit, and by the number of emitted photons. Those conversion factors are obtained of ICRP 74 table 1 and table 17 respectively. This

Calculation of the store house worker dose in a lost wax foundry using MCNP-4C

International Nuclear Information System (INIS)

Alegria, N.; Legarda, F.; Herranz, M.; Idoeta, R.

2005-01-01

Lost wax casting is an industrial process which permits the transmutation into metal of models made in wax. The wax model is covered with a siliceous shell of the required thickness and once this shell is built the set is heated and wax melted. Liquid metal is then cast into the shell replacing the wax. When the metal is cool, the shell is broken away in order to recover the metallic piece. In this process zircon sands are used for the preparation of the siliceous shell. These sands have varying concentrations of natural radionuclides: 238 U, 232 Th and 235 U together with their progenics. The zircon sand is distributed in bags of 50 kg, and 30 bags are on a pallet, weighing 1,500 kg. The pallets with the bags have dimensions 80 cm x 120 cm x 80 cm, and constitute the radiation source in this case. The only pathway of exposure to workers in the store house is external radiation. In this case there is no dust because the bags are closed and covered by plastic, the store house has a good ventilation rate and so radon accumulation is not possible. The workers do not touch with their hands the bags and consequently skin contamination will not take place. In this study all situations of external irradiation to the workers have been considered; transportation of the pallets from vehicle to store house, lifting the pallets to the shelf, resting of the stock on the shelf, getting down the pallets, and carrying the pallets to production area. Using MCNP-4C exposure situations have been simulated, considering that the source has a homogeneous composition, the minimum stock in the store house is constituted by 7 pallets, and the several distances between pallets and workers when they are at work. The photons flux obtained by MCNP-4C is multiplied by the conversion factor of Flux to Kerma for air by conversion factor to Effective Dose by Kerma unit, and by the number of emitted photons. Those conversion factors are obtained of ICRP 74 table 1 and table 17 respectively. This is

Laser-assisted fabrication of batteries on wax paper

International Nuclear Information System (INIS)

Chitnis, G; Ziaie, B; Tan, T

2013-01-01

The functionality of paper-based diagnostic devices can be significantly enhanced by their integration with an on-board energy source. Here, we demonstrate the fabrication of paper-based electrochemical cells on wax paper using CO 2 laser surface treatment and micromachining. A four cell zinc–copper battery shows a steady open-circuit voltage of ∼3 V and can provide 0.25 mA for at least 30 min when connected to a 10 kΩ load. Higher voltages and current values can be obtained by adjusting the number and size of electrochemical cells in the battery without changing the fabrication process. (paper)

Effect of enhanced UV-B radiation of adaxial leaf surface micromorphology and epicuticular wax biosynthesis of sugar maple

International Nuclear Information System (INIS)

Gordon, D.C.; Percy, K.E.; Riding, R.T.

1998-01-01

Sugar maple (Acer saccharum [Marsh.]) seedlings were exposed to UV-B BE ranging from 0.61 kJ m -2 d -1 to 12.48 kJ m -2 d -1 . Increasing UV-B intensity was associated with changes in micromorphological characteristics of the adaxial leaf surface. In vivo incorporation of [1- 14 C] acetate into sugar maple adaxial leaf surface epicuticular wax indicated (p<0.05) a UV-B sensitivity threshold at or near 6.2 kJ m -2 d -1 . Exposure to dosages greater than 6.2 kJ m -2 d -1 resulted in a significant (p<0.05) decrease in wax biosynthesis. The proportion of [1- 14 C] acetate incorporated into each of the different epicuticular wax classes changed with increasing UV-B. Incorporation of [1- 14 C] acetate into alkyl esters decreased while incorporation into alkanes increased with increasing UV-B dose. The effects of enhanced UV-B dose recorded in this experiment may have implications for cuticle function. (author)

Characterisation of wax works of art by gas chromatographic procedures.

Science.gov (United States)

Regert, M; Langlois, J; Colinart, S

2005-10-14

To identify the various natural and synthetic substances used by sculptors at the end of the 19th century, several contemporary reference samples were investigated by high temperature gas chromatography (HT GC) and HT GC-MS. Using specific chromatographic conditions and minimising sample preparation, we could separate, detect and identify a wide range of biomolecular markers covering a great variety of molecular weights and volatilities, with a minimum amount of sample, in a single run. Beeswax, spermaceti, carnauba, candellila and Japan waxes as well as pine resin derivatives, animal fats, paraffin, ozokerite and stearin, used as additives in wax works of art, were chemically investigated. In the case of low volatile compounds, transbutylation was performed. The structure of long-chain esters of spermaceti was elucidated for the first time by HT GC-MS analysis. Such a method was then carried out on 10 samples collected on a statuette of Junon by Antoine-Louis Barye (Louvre Museum, Paris, France) and on a sculpture by Aimé-Jules Dalou (Musée de la Révolution Française, Vizille, France). The analytical results obtained provide new data on the complex recipes elaborated by sculptors at the end of the 19th century.

Anti-inflammatory effects of jojoba liquid wax in experimental models.

Science.gov (United States)

Habashy, Ramy R; Abdel-Naim, Ashraf B; Khalifa, Amani E; Al-Azizi, Mohammed M

2005-02-01

Jojoba [Simmondsia chinensis (Link 1822) Schneider 1907] is an arid perennial shrub grown in several American and African countries. Jojoba seeds, which are rich in liquid wax, were used in folk medicine for diverse ailments. In the current study, the potential anti-inflammatory activity of jojoba liquid wax (JLW) was evaluated in a number of experimental models. Results showed that JLW caused reduction of carrageenin-induced rat paw oedema in addition to diminishing prostaglandin E2 (PGE2) level in the inflammatory exudates. In a test for anti-inflammatory potential utilizing the chick's embryo chroioallantoic membrane (CAM), JLW also caused significant lowering of granulation tissue formation. Topical application of JLW reduced ear oedema induced by croton oil in rats. In the same animal model, JLW also reduced neutrophil infiltration, as indicated by decreased myeloperoxidase (MPO) activity. In addition, JLW ameliorated histopathological changes affected by croton oil application. In the lipopolysaccharide (LPS)-induced inflammation in air pouch in rats, JLW reduced nitric oxide (NO) level and tumor necrosis factor-alpha (TNF-alpha) release. In conclusion, this study demonstrates the effectiveness of JLW in combating inflammation in several experimental models. Further investigations are needed to identify the active constituents responsible for the anti-inflammatory property of JLW.

Oral Health Knowledge and Behaviors among Adolescents with Type 1 Diabetes

Directory of Open Access Journals (Sweden)

Valerie A. Orlando

2010-01-01

Full Text Available Early onset and more advanced periodontal disease has been reported for children with diabetes. We surveyed oral health knowledge, attitudes, and behaviors among adolescents with diabetes in order to inform potential intervention strategies. Study subjects were youth (ages 12–19 years with type 1 diabetes (N = 90 participating in a cohort study investigating determinants of periodontal disease at a regional pediatric diabetes specialty clinic. Over 90% of the youth had been instructed on how to brush and floss and had preventive dental care in the past year. However, 44% knew that periodontal disease is associated with diabetes and 32% knew that it can start in childhood with bleeding gums. Despite being at high risk for developing periodontal disease, the mean toothbrushing frequency was once per day and 42% did not floss. Significant opportunity exists for improving periodontal disease knowledge and adoption of preventive oral hygiene behaviors in adolescents with diabetes.

A method to estimate the fractional fat volume within a ROI of a breast biopsy for WAXS applications: Animal tissue evaluation

International Nuclear Information System (INIS)

Tang, Robert Y.; McDonald, Nancy; Laamanen, Curtis; LeClair, Robert J.

2014-01-01

Purpose: To develop a method to estimate the mean fractional volume of fat (ν ¯ fat ) within a region of interest (ROI) of a tissue sample for wide-angle x-ray scatter (WAXS) applications. A scatter signal from the ROI was obtained and use of ν ¯ fat in a WAXS fat subtraction model provided a way to estimate the differential linear scattering coefficient μ s of the remaining fatless tissue. Methods: The efficacy of the method was tested using animal tissue from a local butcher shop. Formalin fixed samples, 5 mm in diameter 4 mm thick, were prepared. The two main tissue types were fat and meat (fibrous). Pure as well as composite samples consisting of a mixture of the two tissue types were analyzed. For the latter samples, ν fat for the tissue columns of interest were extracted from corresponding pixels in CCD digital x-ray images using a calibration curve. The means ν ¯ fat were then calculated for use in a WAXS fat subtraction model. For the WAXS measurements, the samples were interrogated with a 2.7 mm diameter 50 kV beam and the 6° scattered photons were detected with a CdTe detector subtending a solid angle of 7.75 × 10 −5 sr. Using the scatter spectrum, an estimate of the incident spectrum, and a scatter model, μ s was determined for the tissue in the ROI. For the composite samples, a WAXS fat subtraction model was used to estimate the μ s of the fibrous tissue in the ROI. This signal was compared to μ s of fibrous tissue obtained using a pure fibrous sample. Results: For chicken and beef composites, ν ¯ fat =0.33±0.05 and 0.32 ± 0.05, respectively. The subtractions of these fat components from the WAXS composite signals provided estimates of μ s for chicken and beef fibrous tissue. The differences between the estimates and μ s of fibrous obtained with a pure sample were calculated as a function of the momentum transfer x. A t-test showed that the mean of the differences did not vary from zero in a statistically significant way thereby

Non-Invasive Delivery of dsRNA into De-Waxed Tick Eggs by Electroporation

Science.gov (United States)

Ruiz, Newton; de Abreu, Leonardo Araujo; Parizi, Luís Fernando; Kim, Tae Kwon; Mulenga, Albert; Braz, Gloria Regina Cardoso; Vaz, Itabajara da Silva; Logullo, Carlos

2015-01-01

RNA interference-mediated gene silencing was shown to be an efficient tool for validation of targets that may become anti-tick vaccine components. Here, we demonstrate the application of this approach in the validation of components of molecular signaling cascades, such as the Protein Kinase B (AKT) / Glycogen Synthase Kinase (GSK) axis during tick embryogenesis. It was shown that heptane and hypochlorite treatment of tick eggs can remove wax, affecting corium integrity and but not embryo development. Evidence of AKT and GSK dsRNA delivery into de-waxed eggs of via electroporation is provided. Primers designed to amplify part of the dsRNA delivered into the electroporated eggs dsRNA confirmed its entry in eggs. In addition, it was shown that electroporation is able to deliver the fluorescent stain, 4',6-diamidino-2-phenylindole (DAPI). To confirm gene silencing, a second set of primers was designed outside the dsRNA sequence of target gene. In this assay, the suppression of AKT and GSK transcripts (approximately 50% reduction in both genes) was demonstrated in 7-day-old eggs. Interestingly, silencing of GSK in 7-day-old eggs caused 25% reduction in hatching. Additionally, the effect of silencing AKT and GSK on embryo energy metabolism was evaluated. As expected, knockdown of AKT, which down regulates GSK, the suppressor of glycogen synthesis, decreased glycogen content in electroporated eggs. These data demonstrate that electroporation of de-waxed R. microplus eggs could be used for gene silencing in tick embryos, and improve the knowledge about arthropod embryogenesis. PMID:26091260

Effect of 3 years' free-air exposure to elevated ozone on mature Norway spruce (Picea abies (L.) Karst.) needle epicuticular wax physicochemical characteristics

International Nuclear Information System (INIS)

Percy, Kevin E.; Manninen, Sirkku; Haeberle, Karl-Heinz; Heerdt, C.; Werner, H.; Henderson, Gary W.; Matyssek, Rainer

2009-01-01

We examined the effect of ozone (O 3 ) on Norway spruce (Picea abies) needle epicuticular wax over three seasons at the Kranzberg Ozone Fumigation Experiment. Exposure to 2x ambient O 3 ranged from 64.5 to 74.2 μl O 3 l -1 h AOT40, and 117.1 to 123.2 nl O 3 l -1 4th highest daily maximum 8-h average O 3 concentration. The proportion of current-year needle surface covered by wax tubes, tube aggregates, and plates decreased (P = 0.011) under 2x O 3 . Epistomatal chambers had increased deposits of amorphous wax. Proportion of secondary alcohols varied due to year (P = 0.004) and O 3 treatment (P = 0.029). Secondary alcohols were reduced by 9.1% under 2x O 3 . Exposure to 2x O 3 increased (P = 0.037) proportions of fatty acids by 29%. Opposing trends in secondary alcohols and fatty acids indicate a direct action of O 3 on wax biosynthesis. These results demonstrate O 3 -induced changes in biologically important needle surface characteristics of 50-year-old field-grown trees. - Free-air ozone exposure induced changes in needle wax characteristics of mature Picea abies.

A comparative evaluation of the marginal adaptation of a thermoplastic resin, a light cured wax and an inlay casting wax on stone dies: An in vitro study

Directory of Open Access Journals (Sweden)

Reji P Gopalan

2018-01-01

Conclusion: The marginal adaptation of all the three materials used, was well within the acceptable range of 25–70 μm. The resin pattern materials studied revealed significantly less dimensional change than inlay casting wax on storage at 1, 12, and 24 h time intervals. They may be employed in situations where high precision and delayed investing is expected.

Dental, Dental Hygiene, and Advanced Dental Students' Use, Knowledge, and Beliefs Regarding Tobacco Products.

Science.gov (United States)

Shearston, Jenni A; Shah, Krina; Cheng, Eric; Moosvi, Rizvan; Park, Su Hyun; Patel, Naiya; Spielman, Andrew I; Weitzman, Michael L

2017-11-01

Using cigarettes and alternative tobacco products (ATPs) is associated with negative oral health outcomes, and dental health professionals are poised to help patients quit. The aim of this study was to determine dental, dental hygiene, and advanced dental students' use, knowledge, and beliefs about cigarettes and ATPs, including perceptions about their education in tobacco dependence treatment and counseling experience. All 1,783 students enrolled in the dental, dental hygiene, and postdoctoral dental programs at the New York University College of Dentistry were invited to participate in the survey in 2016. A total of 708 students at least partially completed the survey, for a response rate of 39.7%. In the results, 146 of the students (20.1%) reported ever using cigarettes, while 253 (35.7%) reported ever using any ATP. Regarding tobacco use intervention, the students reported they had not received enough training on ATPs, were neutral about cigarettes, and were somewhat confident and not so confident counseling a cigarette smoker or ATP user, respectively. By their fourth year, 77.8% of the dental students reported they had counseled someone to stop smoking cigarettes, but only 40.7% had counseled someone to stop using ATPs. Overall, all groups of students reported feeling more confident and had received more education on interventions for cigarettes than for ATPs (ptobacco and did not perceive they had received enough training on intervening with patients on use of cigarettes and ATPs. These findings call for a revised tobacco education curriculum for dental, dental hygiene, and advanced dental students, focused on building knowledge and confidence for promoting tobacco dependence treatment.

42 CFR Appendix G to Part 75 - Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography

Science.gov (United States)

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography G Appendix G to Part 75 Public Health PUBLIC HEALTH SERVICE...—Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography The following section...

Design and characterization of sustained release ketoprofen entrapped carnauba wax microparticles.

Science.gov (United States)

Oliveira, Rodinelli B; Nascimento, Thais L; Lima, Eliana M

2012-01-01

Ketoprofen is a non-steroid anti-inflammatory drug (NSAID) used in the treatment of rheumatic diseases and in mild to moderate pain. Ketoprofen has a short biological half-life and the commercially available conventional release formulations require dosages to be administered at least 2-3 times a day. Due to these characteristics, ketoprofen is a good candidate for the preparation of controlled release formulations. In this work, a multiparticulate-sustained release dosage form containing ketoprofen in a carnauba wax matrix was developed. Particles were prepared by an emulsion congealing technique. System variables were optimized using fractional factorial and response surface experimental design. Characterization of the particles included size and morphology, flow rate, drug loading and in vitro drug release. Spherical particles were obtained with high drug load and sustained drug release profile. The optimized particles had an average diameter of approximately 200 µm, 50% (w/w) drug load, good flow properties and prolonged ketoprofen release for more than 24 h. Carnauba wax microspheres prepared in this work represent a new multiparticulate-sustained release system for the NSAID ketoprofen, exhibiting good potential for application in further pharmaceutical processes.

The Biology and Control of the Greater Wax Moth, Galleria mellonella.

Science.gov (United States)

Kwadha, Charles A; Ong'amo, George O; Ndegwa, Paul N; Raina, Suresh K; Fombong, Ayuka T

2017-06-09

The greater wax moth, Galleria mellonella Linnaeus , is a ubiquitous pest of the honeybee, Apis mellifera Linnaeus, and Apis cerana Fabricius . The greater wax moth larvae burrow into the edge of unsealed cells with pollen, bee brood, and honey through to the midrib of honeybee comb. Burrowing larvae leave behind masses of webs which causes galleriasis and later absconding of colonies. The damage caused by G. mellonella larvae is severe in tropical and sub-tropical regions, and is believed to be one of the contributing factors to the decline in both feral and wild honeybee populations. Previously, the pest was considered a nuisance in honeybee colonies, therefore, most studies have focused on the pest as a model for in vivo studies of toxicology and pathogenicity. It is currently widespread, especially in Africa, and the potential of transmitting honeybee viruses has raised legitimate concern, thus, there is need for more studies to find sustainable integrated management strategies. However, our knowledge of this pest is limited. This review provides an overview of the current knowledge on the biology, distribution, economic damage, and management options. In addition, we provide prospects that need consideration for better understanding and management of the pest.

Fluorescent Molecular Rotor-in-Paraffin Waxes for Thermometry and Biometric Identification.

Science.gov (United States)

Jin, Young-Jae; Dogra, Rubal; Cheong, In Woo; Kwak, Giseop

2015-07-08

Novel thermoresponsive sensor systems consisting of a molecular rotor (MR) and paraffin wax (PW) were developed for various thermometric and biometric identification applications. Polydiphenylacetylenes (PDPAs) coupled with long alkyl chains were used as MRs, and PWs of hydrocarbons having 16-20 carbons were utilized as phase-change materials. The PDPAs were successfully dissolved in the molten PWs and did not act as an impurity that prevents phase transition of the PWs. These PDPA-in-PW hybrids had almost the same enthalpies and phase-transition temperatures as the corresponding pure PWs. The hybrids exhibited highly reversible fluorescence (FL) changes at the critical temperatures during phase transition of the PWs. These hybrids were impregnated into common filter paper in the molten state by absorption or were encapsulated into urea resin to enhance their mechanical integrity and cyclic stability during repeated use. The wax papers could be utilized in highly advanced applications including FL image writing/erasing, an array-type thermo-indicator, and fingerprint/palmprint identification. The present findings should facilitate the development of novel fluorescent sensor systems for biometric identification and are potentially applicable for biological and biomedical thermometry.

Comparison of ossification of demineralized bone, hydroxyapatite, Gelfoam, and bone wax in cranial defect repair.

Science.gov (United States)

Papay, F A; Morales, L; Ahmed, O F; Neth, D; Reger, S; Zins, J

1996-09-01

Demineralized bone allografts in the repair of calvarial defects are compared with other common bone fillers. This study uses a video-digitizing radiographic analysis of calvarial defect ossification to determine calcification of bone defects and its relation to postoperative clinical examination and regional controls. The postoperative clinical results at 3 months demonstrated that bony healing was greatest in bur holes filled with demineralized bone and hydroxyapatite. Radiographic analysis demonstrated calcification of demineralized bone-filled defects compared to bone wax- and Gelfoam-filled regions. Hydroxyapatite granules are radiographically dense, thus not allowing accurate measurement of true bone healing. The results suggest that demineralized bone and hydroxyapatite provide better structural support via bone healing to defined calvarial defects than do Gelfoam and bone wax.

Hearing and evasive behavior in the greater wax moth, Galleria mellonella (Pyralidae)

DEFF Research Database (Denmark)

Skals, Niels; Surlykke, Annemarie

2000-01-01

Greater wax moths (Galleria mellonella L., Pyraloidea) use ultrasound sensitive ears to detect clicking conspeci®cs and echolocating bats. Pyralid ears have four sensory cells, A1±4. The audiogram of G. mellonella has best frequency at 60 kHz with a threshold around 47 dB sound pressure level. A1...

Fruit development, pigmentation and biochemical properties of wax apple as affected by localized Application of GA3 under field conditions

Directory of Open Access Journals (Sweden)

Mohammad Moneruzzaman Khandaker

2013-02-01

Full Text Available This study investigated the effects of gibberellin (GA3 on the fruit development, pigmentation and biochemical properties of wax apple. The wax apple trees were rubbing treated with 0, 20, 50 and 100 mgGA3/l under field conditions. The localized application (rubbing of 50 mg GA3/l significantly increased the fruit set, fruit length and diameter, color development, weight and yieldcompared to the control. In addition, GA3 treatments significantly reduced the fruit drop. With regard to the fruit quality, 50 mg/l GA3 treatment increased the juice content, K+, TSS, total sugar and sugar acid ratio of wax apple fruits. In addition, higher vitamin C, phenol, flavonoid, anthocyanin, carotene content, PAL and antioxidant activities were recorded in the treated fruits. There was a positive correlation between the peel colour and TSS content and between the PAL activity and anthocyanin formation in the GA3-treated fruit. It was concluded that rubbing with 50 mg/L GA3 at inflorescence developing point of phloem once a week from the tiny inflorescence bud until the flower opening resulted in better yield and quality of wax apple fruits and could be an effective technique to safe the environment from excessive spray.

Passive vectoring of entomopathogenic fungus Beauveria bassiana among the wax moth Galleria mellonella larvae by the ectoparasitoid Habrobracon hebetor females.

Science.gov (United States)

Kryukov, Vadim Yu; Kryukova, Natalia A; Tyurin, Maksim V; Yaroslavtseva, Olga N; Glupov, Viktor V

2017-03-15

Females of the ectoparasitoid Habrobracon hebetor attack and envenomate numerous host individuals during oviposition. The vectoring of the entomopathogenic fungus Beauveria bassiana during the adhesion stage by ectoparasitoid females among the wax moth larvae Galleria mellonella was explored under laboratory conditions. Vectoring occurred both from infected parasitoids to wax moth larvae and from infected to healthy wax moth larvae by parasitoids. The efficacy of vectoring in both cases was dose dependent. Parasitoid females were unable to recognize infected larvae in a labyrinth test. In addition, the presence of H. hebetor females significantly (1.5-13 fold) increased the mycoses level in clusters of G. mellonella, with 40% of the larvae infected with fungal conidia. Envenomation by H. hebetor increased conidia germination on the cuticles of the wax moth larvae by 4.4 fold. An enhanced germination rate (2 fold) was registered in the n-hexane epicuticular extract of envenomated larvae compared to that of healthy larvae. Both envenomation and mycoses enhanced the phenoloxidase (PO) activity in the integument of G. mellonella and, in contrast, decreased the encapsulation rate in hemolymphs. We hypothesize that changes in the integument property and inhibition of cellular immunity provide the highest infection efficacy of entomopathogenic fungi with H. hebetor. © 2017 Institute of Zoology, Chinese Academy of Sciences.

The fit of cobalt-chromium three-unit fixed dental prostheses fabricated with four different techniques: a comparative in vitro study.

Science.gov (United States)

Örtorp, Anders; Jönsson, David; Mouhsen, Alaa; Vult von Steyern, Per

2011-04-01

This study sought to evaluate and compare the marginal and internal fit in vitro of three-unit FDPs in Co-Cr made using four fabrication techniques, and to conclude in which area the largest misfit is present. An epoxy resin master model was produced. The impression was first made with silicone, and master and working models were then produced. A total of 32 three-unit Co-Cr FDPs were fabricated with four different production techniques: conventional lost-wax method (LW), milled wax with lost-wax method (MW), milled Co-Cr (MC), and direct laser metal sintering (DLMS). Each of the four groups consisted of eight FDPs (test groups). The FDPs were cemented on their cast and standardised-sectioned. The cement film thickness of the marginal and internal gaps was measured in a stereomicroscope, digital photos were taken at 12× magnification and then analyzed using measurement software. Statistical analyses were performed with one-way ANOVA and Tukey's test. Best fit based on the means (SDs) in μm for all measurement points was in the DLMS group 84 (60) followed by MW 117 (89), LW 133 (89) and MC 166 (135). Significant differences were present between MC and DLMS (p<0.05). The regression analyses presented differences within the parameters: production technique, tooth size, position and measurement point (p < 0.05). Best fit was found in the DLMS group followed by MW, LW and MC. In all four groups, best fit in both abutments was along the axial walls and in the deepest part of the chamfer preparation. The greatest misfit was present occlusally in all specimens. Copyright © 2010 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Does dental caries affect dental development in children and adolescents?

Science.gov (United States)

Dhamo, Brunilda; Elezi, Besiana; Kragt, Lea; Wolvius, Eppo B; Ongkosuwito, Edwin M

2018-01-01

Although a link between dietary changes, caries, and dental development has been observed, the literature provides little insight about this relationship. The aim of our study was to investigate the association between dental caries and dental development in a clinical sample of Albanian children and adolescents. In total, 118 children and adolescents, born between 1995 and 2004 and aged 6–15 years, were included. Dental caries in the deciduous dentition was assessed using the Decayed, Filled Teeth (dft) index and dental caries in the permanent dentition was assessed using the Decayed, Missing, Filled Teeth (DMFT) index. Dental development during the permanent dentition was determined using the Demirjian method. Linear and ordinal regression models were applied to analyze the associations of dental caries with dental age and developmental stages of each left mandibular tooth. Dental caries in the deciduous dentition, estimated as a median dft of 2.0 (90% range, 0.0–9.1), was significantly associated with lower dental age (β = -0.21; 90% CI: -0.29, -0.12) and with delayed development of the canine, both premolars, and the second molar. Untreated dental caries (dt) was associated with lower dental age (β = -0.19; 90% CI: -0.28, -0.10). Dental caries in the permanent dentition, estimated as a median DMFT of 1.0 (90% range, 0.0–8.0), was not significantly associated with dental age (β = 0.05; 90% CI: -0.04, 0.14). However, the DMFT was associated with the advanced stages of development of both premolars and the second molar. The untreated dental caries in the deciduous dentition delays the development of permanent teeth. PMID:29659350

Physical stability, centrifugation tests, and entrapment efficiency studies of carnauba wax-decyl oleate nanoparticles used for the dispersion of inorganic sunscreens in aqueous media.

Science.gov (United States)

Villalobos-Hernández, J R; Müller-Goymann, C C

2006-06-01

Aqueous nanoscale lipid dispersions consisting of carnauba wax-decyl oleate mixtures acting as carriers or accompanying vehicles for inorganic sunscreens such as barium sulfate, strontium carbonate, and titanium dioxide were prepared by high pressure homogenization. For the manufacture of these nanosuspensions, three pigment concentrations (%wt), namely 2, 4, and 6, and two carnauba wax-decyl oleate ratios, 1:1 and 2:1, were used, being some of these combinations chosen for stability studies. Six-month physical stability tests at 4, 20, and 40 degrees C selecting the mean particle size and the polydispersity index of the nanosuspensions as reference parameters were performed. Centrifugation tests of the nanosuspensions assessed by transmission electron microscopy and by the determination of the content of pigments and carnauba wax in the separated fractions were done. The mean particle sizes and the polydispersity indices of the nanosuspensions were not altered after six-month storages at 20 and at 40 degrees C. However, the storage of those at 4 degrees C considerably increased the particle size and polydispersity of the systems, particularly when wax-oil ratios (2:1) were used for the entrapment of the pigments. Transmission electron micrographs of centrifuged samples denoted the presence of three major fractions showing the different types of particles integrated into the nanosuspensions. Furthermore, it was observed that not all the carnauba wax participated in the entrapment of the pigment. Regarding the amount of pigment being encapsulated or bonded by the wax-oil matrices, entrapment efficiencies higher than 85.52% were reported.

Propolis and vegetable wax in the conservation of Hass avocadoPrópolis e cera vegetal na conservação de abacate Hass

Directory of Open Access Journals (Sweden)

Ricardo de Oliveira Orsi

2012-08-01

Full Text Available The aim of this work was to evaluate the quality of Hass avocado submitted to application of propolis and vegetable wax. The selected fruits were submitted to the treatments (1 without wax and without propolis, (2 with vegetable wax, (3 propolis alcoholic extract 100%, (4 wax and etanol 70%, (5 propolis alcoholic extract 2% and wax, (6 propolis alcoholic extract 4% and wax, (7 propolis alcoholic extract 6% and wax, (8 propolis alcoholic extract 8% and wax, and (9 propolis alcoholic extract 10% and wax. The fruits were maintained under refrigeration (10 ± 1 ºC and 90 ± 5% relative humidity, being appraised every three days for 15 days and more 3 days of commercialization simulation at room temperature (23± 1 ºC and 18% relative humidity.The evaluation parameters were the weight loss, respiratory activity, pH, firmness, tritable acidity (AT, soluble solids (SS, and ratio. The results of weigth loss, respiratory activity and firmness were the most significant to show the difference among the treatments. ‘Hass’ avocado fruits submitted the application of propolis associated the vegetable wax present smaller weight loss, CO2 production and firmness in relation to the control fruits. The fruits of the treatment with propolis alcoholic extract 2% and wax presented the most promising results. Objetivou-se neste trabalho avaliar a aplicação de própolis e cera vegetal na qualidade pós-colheita do abacate ‘Hass’. Os frutos selecionados foram submetidos aos tratamentos (1 sem cera e sem própolis, (2 com cera vegetal, (3 extrato alcoólico de própolis 100%, (4 cera e etanol 70%, (5 extrato alcoólico de própolis 2% e cera, (6 extrato alcoólico de própolis 4% e cera, (7 extrato alcoólico de própolis 6% e cera, (8 extrato alcoólico de própolis 8% e cera e (9 extrato alcoólico de própolis 10% e cera. Os frutos foram mantidos sob refrigeração (10 ± 1 ºC e 90 ± 5% umidade relativa, sendo avaliados a cada três dias durante 15 dias

Comparative study to evaluate the accuracy of polyether occlusal bite registration material and occlusal registration wax as a guide for occlusal reduction during tooth preparation

Directory of Open Access Journals (Sweden)

Niranjan Joshi

2013-01-01

Objective: The objective of this study was to compare and evaluate the reliability of the most commonly used occlusal registration wax that with polyether bite registration material as a guide for occlusal reduction required during tooth preparations. Materials and Methods: For the purpose of this study, 25 abutment teeth requiring tooth preparation for fixed prosthesis were selected and tooth preparations carried out. Modeling wax strips of specific dimensions were placed onto the cast of prepared tooth, which was mounted on maximum intercuspation on the articulator and the articulator was closed. The thickness of the wax registration was measured at three zones namely two functional cusps and central fossa. Similar measurements were made using the polyether bite registration material and prosthesis at the same zones. The data was tabulated and was subjected to statistical analysis using anova test and Tukey honestly significant difference test. Results: The differences in thickness between wax record and prosthesis by 0.1346 mm, whereas the difference between polyether and prosthesis was 0.02 mm with a P value of 0.042, which is statistically significant. This means that the wax record was 8.25% larger than the prosthesis while polyether was just 1.27% larger than the prosthesis. Conclusion: The clinical significance of the above analysis is that Ramitec polyether bite registration material is most suitable material when compared with commonly used modeling wax during the tooth preparation.

Dental formulations for the prevention of dental erosion

DEFF Research Database (Denmark)

2010-01-01

The invention relates to a therapeutic method for preventing and/or inhibiting dental erosion in a mammalian subject, and the provision of a dental care product for performing the method. The dental care product of the invention comprises a starch-degrading enzyme of E. C. 3.2.1.1, wherein said...... product comprises less than 1 wt.% ionic surfactant, and preferably is substantially free of endoprotease and/or lipase. The properties of the dental care product serve to prevent and/or inhibit dental erosion in a subject that typically results from repeated exposure of the patient's tooth surfaces...

Stable hydrogen isotopic composition of n-alkanes in atmospheric aerosols as a tracer for the source region of terrestrial plant waxes

Science.gov (United States)

Yamamoto, S.; Kawamura, K.

2009-12-01

Studies on molecular composition and compound-specific carbon isotopic ratio (δ13C) of leaf wax n-alkanes in atmospheric aerosols have revealed a long-range atmospheric transport of terrestrial higher plant materials over the south Atlantic and western Pacific oceans. However, molecular and δ13C compositions of terrestrial plant waxes in the eastern part of the Asian continent are relatively constant reflecting C3-dominated vegetation, which makes it difficult to specify the source regions of plant materials in the atmospheric aerosols over the East Asia and northwest Pacific regions. Recent observation displays a large (>100‰) spatial variation in hydrogen isotopic composition (δD) of rainwater in East Asia. Because δD values of terrestrial higher plants sensitively reflect those of precipitation waters, δD of leaf waxes are expected to provide information on their source region. In this study, we measured the δD of n-alkanes in atmospheric aerosols from Tokyo to better understand the origin of leaf wax n-alkanes in atmospheric aerosols. The δD values of fossil fuel n-alkanes (C21 to C24) in Tokyo aerosols range from -65 to -94‰, which are in a range of those reported in marine crude oils. In contrast, the δD of higher molecular weight (C29 and C31) n-alkanes (δDHMW) show much larger values by ~70‰ than those of fossil fuel n-alkanes. Their values were found to exhibit concomitant variations with carbon preference index (CPI), suggesting that the δDHMW reflect the δD of leaf wax n-alkanes with a variable contribution from fossil fuel n-alkanes. Nevertheless, good positive correlation (r = 0.89, p < 0.01) between the δDHMW and CPI values enable us to remove the contribution of fossil fuels using a mass balance approach by assuming that CPI of fossil fuel is 1 and CPI of plant waxes is 5-15. Calculated n-alkane δD values averaged from -170 to -185‰ for C29 and from -155 to -168‰ for C31. These values are consistent with those reported from

Effect of 3 years' free-air exposure to elevated ozone on mature Norway spruce (Picea abies (L.) Karst.) needle epicuticular wax physicochemical characteristics

Energy Technology Data Exchange (ETDEWEB)

Percy, Kevin E., E-mail: kpercy@nbnet.nb.c [Natural Resources Canada, Canadian Forest Service-Atlantic Forestry Centre, 1350 Regent Street, Fredericton, NB, E3B 5P7 (Canada); Manninen, Sirkku [Department of Biological and Environmental Sciences, P.O. Box 56, University of Helsinki, 00014 Helsinki (Finland); Department of Biology, P.O. Box 3000, University of Oulu, 90014 Oulu (Finland); Haeberle, Karl-Heinz [Ecophysiology of Plants, Department of Ecology, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany); Heerdt, C.; Werner, H. [Ecoclimatology, Department of Ecology, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany); Henderson, Gary W. [Natural Resources Canada, Canadian Forest Service-Atlantic Forestry Centre, 1350 Regent Street, Fredericton, NB, E3B 5P7 (Canada); Matyssek, Rainer [Ecophysiology of Plants, Department of Ecology, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany)

2009-05-15

We examined the effect of ozone (O{sub 3}) on Norway spruce (Picea abies) needle epicuticular wax over three seasons at the Kranzberg Ozone Fumigation Experiment. Exposure to 2x ambient O{sub 3} ranged from 64.5 to 74.2 mul O{sub 3} l{sup -1} h AOT40, and 117.1 to 123.2 nl O{sub 3} l{sup -1} 4th highest daily maximum 8-h average O{sub 3} concentration. The proportion of current-year needle surface covered by wax tubes, tube aggregates, and plates decreased (P = 0.011) under 2x O{sub 3}. Epistomatal chambers had increased deposits of amorphous wax. Proportion of secondary alcohols varied due to year (P = 0.004) and O{sub 3} treatment (P = 0.029). Secondary alcohols were reduced by 9.1% under 2x O{sub 3}. Exposure to 2x O{sub 3} increased (P = 0.037) proportions of fatty acids by 29%. Opposing trends in secondary alcohols and fatty acids indicate a direct action of O{sub 3} on wax biosynthesis. These results demonstrate O{sub 3}-induced changes in biologically important needle surface characteristics of 50-year-old field-grown trees. - Free-air ozone exposure induced changes in needle wax characteristics of mature Picea abies.

Patients' satisfaction with dental care provided by public dental ...

African Journals Online (AJOL)

Background: In Tanzania, patient satisfaction with dental services has received only minor attention. Objective: To assess patients' satisfaction with public dental health services in Dar es Salaam. Design: A cross-sectional study. Setting: Five public dental clinics randomly selected from a list of all the nine public dental ...

Trimethylamine (fishy odor) adsorption by biomaterials: effect of fatty acids, alkanes, and aromatic compounds in waxes.

Science.gov (United States)

Boraphech, Phattara; Thiravetyan, Paitip

2015-03-02

Thirteen plant leaf materials were selected to be applied as dried biomaterial adsorbents for polar gaseous trimethylamine (TMA) adsorption. Biomaterial adsorbents were efficient in adsorbing gaseous TMA up to 100% of total TMA (100 ppm) within 24 h. Sansevieria trifasciata is the most effective plant leaf material while Plerocarpus indicus was the least effective in TMA adsorption. Activated carbon (AC) was found to be lower potential adsorbent to adsorb TMA when compared to biomaterial adsorbents. As adsorption data, the Langmuir isotherm supported that the gaseous TMA adsorbed monolayer on the adsorbent surface and was followed pseudo-second order kinetic model. Wax extracted from plant leaf could also adsorb gaseous TMA up to 69% of total TMA within 24 h. Another 27-63% of TMA was adsorbed by cellulose and lignin that naturally occur in high amounts in plant leaf. Subsequently, the composition appearing in biomaterial wax showed a large quantity of short-chain fatty acids (≤C18) especially octadecanoic acid (C18), and short-chain alkanes (C12-C18) as well as total aromatic components dominated in the wax, which affected TMA adsorption. Hence, it has been demonstrated that plant biomaterial is a superior biosorbent for TMA removal.

A method to estimate the fractional fat volume within a ROI of a breast biopsy for WAXS applications: Animal tissue evaluation

Energy Technology Data Exchange (ETDEWEB)

Tang, Robert Y., E-mail: rx-tang@laurentian.ca [Biomolecular Sciences Program, Laurentian University, 935 Ramsey Lake Road, Sudbury, Ontario P3E 2C6 (Canada); McDonald, Nancy, E-mail: mcdnancye@gmail.com; Laamanen, Curtis, E-mail: cx-laamanen@laurentian.ca [Department of Physics, Laurentian University, 935 Ramsey Lake Road, Sudbury, Ontario P3E 2C6 (Canada); LeClair, Robert J., E-mail: rleclair@laurentian.ca [Department of Physics, Laurentian University, 935 Ramsey Lake Road, Sudbury, Ontario P3E 2C6, Canada and Biomolecular Sciences Program, Laurentian University, 935 Ramsey Lake Road, Sudbury, Ontario P3E 2C6 (Canada)

2014-11-01

Purpose: To develop a method to estimate the mean fractional volume of fat (ν{sup ¯}{sub fat}) within a region of interest (ROI) of a tissue sample for wide-angle x-ray scatter (WAXS) applications. A scatter signal from the ROI was obtained and use of ν{sup ¯}{sub fat} in a WAXS fat subtraction model provided a way to estimate the differential linear scattering coefficient μ{sub s} of the remaining fatless tissue. Methods: The efficacy of the method was tested using animal tissue from a local butcher shop. Formalin fixed samples, 5 mm in diameter 4 mm thick, were prepared. The two main tissue types were fat and meat (fibrous). Pure as well as composite samples consisting of a mixture of the two tissue types were analyzed. For the latter samples, ν{sub fat} for the tissue columns of interest were extracted from corresponding pixels in CCD digital x-ray images using a calibration curve. The means ν{sup ¯}{sub fat} were then calculated for use in a WAXS fat subtraction model. For the WAXS measurements, the samples were interrogated with a 2.7 mm diameter 50 kV beam and the 6° scattered photons were detected with a CdTe detector subtending a solid angle of 7.75 × 10{sup −5} sr. Using the scatter spectrum, an estimate of the incident spectrum, and a scatter model, μ{sub s} was determined for the tissue in the ROI. For the composite samples, a WAXS fat subtraction model was used to estimate the μ{sub s} of the fibrous tissue in the ROI. This signal was compared to μ{sub s} of fibrous tissue obtained using a pure fibrous sample. Results: For chicken and beef composites, ν{sup ¯}{sub fat}=0.33±0.05 and 0.32 ± 0.05, respectively. The subtractions of these fat components from the WAXS composite signals provided estimates of μ{sub s} for chicken and beef fibrous tissue. The differences between the estimates and μ{sub s} of fibrous obtained with a pure sample were calculated as a function of the momentum transfer x. A t-test showed that the mean of the

Effect of expanded graphite on the phase change materials of high density polyethylene/wax blends

Energy Technology Data Exchange (ETDEWEB)

AlMaadeed, M.A., E-mail: m.alali@qu.edu.qa [Center for Advanced Materials, Qatar University, 2713 Doha (Qatar); Labidi, Sami [Center for Advanced Materials, Qatar University, 2713 Doha (Qatar); Krupa, Igor [QAPCO Polymer Chair, Center for Advanced Materials, Qatar University, P.O. Box 2713, Doha (Qatar); Karkri, Mustapha [Université Paris-Est CERTES, 61 avenue du Général de Gaulle, 94010 Créteil (France)

2015-01-20

Highlights: • Expanded graphite (EG) and low melting point (42.3 °C) wax were added to HDPE to form phase change material. • EG was well dispersed in the composites and did not affect the melting or crystallization of the HDPE matrix. • EG increased the thermal stability of the composites by reducing chain mobility and inhibiting degradation. • The addition of a relatively small quantity of EG enhances the heat conduction in the composite. • HDPE/40% RT42 that contained up to 15% EG demonstrated excellent mechanical and thermal properties and can be used as PCM. - Abstract: Phase change materials fabricated from high density polyethylene (HDPE) blended with 40 or 50 wt% commercial wax (melting point of 43.08 °C) and up to 15 wt% expanded graphite (EG) were studied. Techniques including scanning electron microscope (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and an experimental device to measure diffusivity and conductivity (DICO) were used to determine the microstructural, mechanical and thermal properties of the composites. The composites possessed good mechanical properties. Additionally, no leaching was observed during material processing or characterization. Although the Young’s modulus increased with the addition of EG, no significant changes in tensile strength were detected. The maximum Young’s modulus achieved was 650 MPa for the HDPE/40% wax composite with 15 wt% EG. The EG was well dispersed within the composites and did not affect the melting or crystallization of the HDPE matrix. The incorporation of EG increased the thermal stability of the composites by reducing chain mobility and inhibiting degradation. The intensification of thermal conductivity occurred with increasing fractions of EG, which was attributed to the high thermal conductivity of graphite. The maximum quantity of heat stored by latent heat was found for the HDPE/40% wax composite with EG. The addition of a relatively small quantity

Effect of expanded graphite on the phase change materials of high density polyethylene/wax blends

International Nuclear Information System (INIS)

AlMaadeed, M.A.; Labidi, Sami; Krupa, Igor; Karkri, Mustapha

2015-01-01

Highlights: • Expanded graphite (EG) and low melting point (42.3 °C) wax were added to HDPE to form phase change material. • EG was well dispersed in the composites and did not affect the melting or crystallization of the HDPE matrix. • EG increased the thermal stability of the composites by reducing chain mobility and inhibiting degradation. • The addition of a relatively small quantity of EG enhances the heat conduction in the composite. • HDPE/40% RT42 that contained up to 15% EG demonstrated excellent mechanical and thermal properties and can be used as PCM. - Abstract: Phase change materials fabricated from high density polyethylene (HDPE) blended with 40 or 50 wt% commercial wax (melting point of 43.08 °C) and up to 15 wt% expanded graphite (EG) were studied. Techniques including scanning electron microscope (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and an experimental device to measure diffusivity and conductivity (DICO) were used to determine the microstructural, mechanical and thermal properties of the composites. The composites possessed good mechanical properties. Additionally, no leaching was observed during material processing or characterization. Although the Young’s modulus increased with the addition of EG, no significant changes in tensile strength were detected. The maximum Young’s modulus achieved was 650 MPa for the HDPE/40% wax composite with 15 wt% EG. The EG was well dispersed within the composites and did not affect the melting or crystallization of the HDPE matrix. The incorporation of EG increased the thermal stability of the composites by reducing chain mobility and inhibiting degradation. The intensification of thermal conductivity occurred with increasing fractions of EG, which was attributed to the high thermal conductivity of graphite. The maximum quantity of heat stored by latent heat was found for the HDPE/40% wax composite with EG. The addition of a relatively small quantity

Description and Documentation of the Dental School Dental Delivery System.

Science.gov (United States)

Chase, Rosen and Wallace, Inc., Alexandria, VA.

A study was undertaken to describe and document the dental school dental delivery system using an integrated systems approach. In late 1976 and early 1977, a team of systems analysts and dental consultants visited three dental schools to observe the delivery of dental services and patient flow and to interview administrative staff and faculty.…

Antiprotozoal activity of extracts and isolated triterpenoids of 'carnauba' (Copernicia prunifera) wax from Brazil.

Science.gov (United States)

de Almeida, Buana C; Araújo, Bruno Q; Carvalho, Adonias A; Freitas, Sâmya Danielle L; Maciel, Dayany da S Alves; Ferreira, Ari José S; Tempone, Andre G; Martins, Ligia F; Alexandre, Tatiana R; Chaves, Mariana H; Lago, João Henrique G

2016-12-01

'Carnauba' wax is a natural product obtained from the processing of the powder exuded from Copernicia prunifera (Miller) H. E. Moore (Arecaceae). This material is widely used in the Brazilian folk medicine, including the treatment of rheumatism and syphilis. To investigate the antiprotozoal activity of hexane and EtOH extracts from the 'carnauba' wax as well as from the isolated compounds from the bioactive extracts. Two different samples of 'carnauba' (C. prunifera) waxes - types 1 and 4 - were individually extracted using hexane (EH) and EtOH (EE). Aliquots of hexane (type 1 - EH-1 and EH-4) and EtOH (type 4 - EE-1 and EE-4) extracts were tested against promastigote (2-200 μg/mL in DMSO during 48 h at 24 °C) and amastigote (3-150 μg/mL in DMSO during 120 h at 37 °C) forms of Leishmania infantum as well as against trypomastigote (3-150 μg/mL in DMSO during 24 h at 37 °C) forms of Trypanosoma cruzi. Bioactive extracts EH-1 and EE-4 were subjected to a bioactivity-guided fractionation to afford three dammarane-type triterpenoids (1-3). The in vitro antiprotozoal activities of the obtained compounds were evaluated as described above. Additionally, the cytotoxicity activity of compounds 1-3 against mammalian conjunctive cells (NCTC - 2-200 μg/mL in DMSO during 48 h at 37 °C) was determined. From the bioactive hexane and EtOH extracts from the 'carnauba' (C. prunifera) wax, were isolated three dammarane-type triterpenoids: (24R*)-methyldammar-25-ene-3β,20-diol (carnaubadiol, 1), (24R*)-methyldammara-20,25-dien-3-one (2) and (24R*)-methyldammara-20,25-dien-3α-ol (3). These compounds were identified based on the analysis of NMR and MS spectroscopic data. Compounds 1-3 were effective against the intracellular amastigotes of L. infantum, with IC 50 values ranging from 8 to 52 μM, while compounds 1 and 3 displayed activity against trypomastigote forms of T. cruzi with IC 50 values of 15 and 35 μM, respectively. The mammalian

Extracting paraffin and mineral waxes

Energy Technology Data Exchange (ETDEWEB)

Carpenter, I C

1930-01-17

In a process for freezing liquids, particularly for precipitating wax from oils such as petroleum or shale oils, the liquid to be treated is cooled first in vessels 10, 11, and 12 by chilled liquid from the final separating tanks 22, then in vessels 13, 14 and 15 by brine cooled by an evaporator 38 and finally in vessels 16,17, 18 directly by the evaporator of a refrigerating plant. The cooling in vessels 10, 11, 12 is regulated by recirculating some of the chilled liquid through the valved pipe 30 while that in tanks 13, 14, 15 is regulated by short-circuiting the brine circulation through a tank 35. Refrigerant vapour from the evaporators in vessels 16, 17, 18 may return through pipe 61 to the compressor or absorber of the plant 45 or it may be withdrawn by pump 58. By the operation of valves A, B, 47, and a valve in pipe 61, the pressures in the evaporators may be varied individually to regulate the cooling in each vessel. Mechanical stirrers are provided in tanks 16, 17, 18.

Dental anxiety and salivary cortisol levels before urgent dental care.

Science.gov (United States)

Kanegane, Kazue; Penha, Sibele S; Munhoz, Carolina D; Rocha, Rodney G

2009-12-01

Dental anxiety is still prevalent, despite advances in treatment, and affects the utilization of health care services. The purpose of this cross-sectional study was to determine if patients with different degrees of dental anxiety and pain undergoing emergency dental care have different stress reactions as measured by salivary cortisol. Seventy three patients completed the modified dental anxiety scale (MDAS), and described any previous dental traumatic experience. Their socio-demographic characteristics were also recorded. They also rated pain intensity on a 100 mm visual analogue scale (VAS). A saliva sample was collected before the procedure, and analyzed by enzyme immunoassay. Thirty patients were dentally anxious and forty one complained of pain. In this sample, dental anxiety was not related to gender, age, educational level and family income; however, a previous traumatic event was related to dental anxiety. There was no association between salivary cortisol concentrations and gender or dental anxiety. Patients with pain showed higher cortisol levels. When gathering patient information, the dentist should note patients' negative dental experiences in order to provide more effective, less traumatic treatment.

SEPARATION OF FISCHER-TROPSCH WAX FROM CATALYST BY SUPERCRITICAL EXTRACTION

Energy Technology Data Exchange (ETDEWEB)

Patrick C. Joyce; Mark C. Thies

1999-03-31

The objective of this research project was to evaluate the potential of supercritical fluid (SCF) extraction for the recovery and fractionation of the wax product from the slurry bubble column (SBC) reactor of the Fischer-Tropsch (F-T) process. The wax, comprised mostly of branched and linear alkanes with a broad molecular weight distribution up to C{sub 100}, is to be extracted with a hydrocarbon solvent that has a critical temperature near the operating temperature of the SBC reactor, i.e., 200-300 C. Aspen Plus{trademark} was used to perform process simulation studies on the proposed extraction process, with Redlich-Kwong-Soave (RKS) being used for the thermodynamic property model. In summary, we have made comprehensive VLE measurements for short alkane + long alkane systems over a wide range of pressures and temperatures, dramatically increasing the amount of high-quality data available for these simple, yet highly relevant systems. In addition, our work has demonstrated that, surprisingly, no current thermodynamic model can adequately predict VLE behavior for these systems. Thus, process simulations (such as those for our proposed SCF extraction process) that incorporate these systems can currently only give results that are qualitative at best. Although significant progress has been made in the past decade, more experimental and theoretical work remain to be done before the phase equilibria of asymmetric alkane mixtures can be predicted with confidence.

Purifying oils and waxes. [British patent

Energy Technology Data Exchange (ETDEWEB)

1926-01-27

Fractions of petroleum, shale oil, coal oil, and paraffin wax are refined by passing the vapour under reduced pressure through fuller's earth, bauxite, silica gel, or other adsorbent at a temperature not substantially more than sufficient to maintain the vapour phase. The vapour may be passed in succession through adsorbent of increasing strength. Treatment with sulphuric acid, or with alkali, or with both may precede treatment with absorbent, and this successive treatment may be repeated any number of times. The action is accelerated by passing a current of inert gas insufficient to affect the vacuum materially along with the vapours. In an example a 160 to 225/sup 0/C kerosene fraction is treated with sulphuric acid of 10 percent strength, and passed into a fuller's earth chamber under a vacuum of 27 in. of mercury and heated by steam to about 140/sup 0/C. The apparatus is described.

Functional expression and characterization of five wax ester synthases in Saccharomyces cerevisiae and their utility for biodiesel production

Directory of Open Access Journals (Sweden)

Shi Shuobo

2012-02-01

Full Text Available Abstract Background Wax ester synthases (WSs can synthesize wax esters from alcohols and fatty acyl coenzyme A thioesters. The knowledge of the preferred substrates for each WS allows the use of yeast cells for the production of wax esters that are high-value materials and can be used in a variety of industrial applications. The products of WSs include fatty acid ethyl esters, which can be directly used as biodiesel. Results Here, heterologous WSs derived from five different organisms were successfully expressed and evaluated for their substrate preference in Saccharomyces cerevisiae. We investigated the potential of the different WSs for biodiesel (that is, fatty acid ethyl esters production in S. cerevisiae. All investigated WSs, from Acinetobacter baylyi ADP1, Marinobacter hydrocarbonoclasticus DSM 8798, Rhodococcus opacus PD630, Mus musculus C57BL/6 and Psychrobacter arcticus 273-4, have different substrate specificities, but they can all lead to the formation of biodiesel. The best biodiesel producing strain was found to be the one expressing WS from M. hydrocarbonoclasticus DSM 8798 that resulted in a biodiesel titer of 6.3 mg/L. To further enhance biodiesel production, acetyl coenzyme A carboxylase was up-regulated, which resulted in a 30% increase in biodiesel production. Conclusions Five WSs from different species were functionally expressed and their substrate preference characterized in S. cerevisiae, thus constructing cell factories for the production of specific kinds of wax ester. WS from M. hydrocarbonoclasticus showed the highest preference for ethanol compared to the other WSs, and could permit the engineered S. cerevisiae to produce biodiesel.

Awareness of dental implants among dental patients in Nigeria ...

African Journals Online (AJOL)

The aim of this study was to determine the level of awareness of dental implant in Nigerian patients and their willingness to choose dental implant as a tooth replacement option. A survey was conducted among patients presenting for dental treatment in 3 teaching hospitals and private dental clinics in 3 urban cities of ...

Dental, Dental Hygiene, and Graduate Students' and Faculty Perspectives on Dental Hygienists' Professional Role and the Potential Contribution of a Peer Teaching Program.

Science.gov (United States)

McComas, Martha J; Inglehart, Marita R

2016-09-01

The changing role of dental hygienists deserves dental and dental hygiene educators' attention. The first aim of this survey study was to assess University of Michigan dental, dental hygiene, and graduate students' and faculty members' perceptions of dental hygienists' roles; their attitudes and behaviors related to clinical interactions between dental and dental hygiene students; and perceived benefits of engaging dental hygiene students as peer teachers for dental students. The second aim was to assess whether one group of dental students' experiences with dental hygiene student peer teaching affected their perceptions of the dental hygiene profession. Survey respondents were 57 dental hygiene students in all three years of the program (response rate 60% to 100%); 476 dental students in all four years (response rate 56% to 100%); 28 dental and dental hygiene graduate students (response rate 28%); and 67 dental and dental hygiene faculty members (response rate 56%). Compared to the other groups, dental students reported the lowest average number of services dental hygienists can provide (p≤0.001) and the lowest average number of patient groups for which dental hygienists can provide periodontal care (ppeer teaching (ppeer teaching. After experiencing dental hygiene student peer teaching, the dental students' perceptions of dental hygienists' roles, attitudes about clinical interactions with dental hygienists, and perceived benefits of dental hygiene student peer teachers improved and were more positive than the responses of their peers with no peer teaching experiences. These results suggest that dental hygiene student peer teaching may improve dental students' perceptions of dental hygienists' roles and attitudes about intraprofessional care.

The Effect of Water or Wax-based Binders on the Chemical and Morphological Characteristics of the Margin Ceramic-Framework Interface.

Science.gov (United States)

Güler, Umut; de Queiroz, José Renato Cavalcanti; de Oliveira, Luiz Fernando Cappa; Canay, Senay; Ozcan, Mutlu

2015-09-01

This study evaluated the effect of binder choice in mixing ceramic powder on the chemical and morphological features between the margin ceramic-framework interfaces. Titanium and zirconia frameworks (15 x 5 x 0.5 mm3) were veneered with margin ceramics prepared with two different binders, namely a) water/conventional or b) wax-based. For each zirconia framework material, four different margin ceramics were used: a- Creation Zi (Creation Willi Geller International); b- GC Initial Zr (GC America); Triceram (Dentaurum); and d- IPS emax (voclar Vivadent). For the titanium framework, three different margin ceramics were used: a- Creation Ti (Creation Willi Geller International); b- Triceram (Dentaurum); and c- VITA Titaniumkeramik (Vita Zahnfabrik). The chemical composition of the framework-margin ceramic interface was analyzed using Energy Dispersive X-ray Spectroscopy (EDS) and porosity level was quantified within the margin ceramic using an image program (ImageJ) from four random areas (100 x 100 pixels) on each SEM image. EDS analysis showed the presence of Carbon at the margin ceramic-framework interface in the groups where wax-based binder technique was used with the concentration being the highest for the IPS emax ZirCAD group. While IPS system (IPS ZirCAD and IPS Emax) presented higher porosity concentration using wax binder, in the other groups wax-based binder reduced the porosity of margin ceramic, except for Titanium - Triceram combination.

Dental Workforce Availability and Dental Services Utilization in Appalachia: A Geospatial Analysis

Science.gov (United States)

Feng, Xue; Sambamoorthi, Usha; Wiener, R. Constance

2016-01-01

Objectives There is considerable variation in dental services utilization across Appalachian counties, and a plausible explanation is that individuals in some geographical areas do not utilize dental care due to dental workforce shortage. We conducted an ecological study on dental workforce availability and dental services utilization in Appalachia. Methods We derived county-level (n = 364) data on demographic, socio-economic characteristics and dental services utilization in Appalachia from the 2010 Behavioral Risk Factor Surveillance System (BRFSS) using person-level data. We obtained county-level dental workforce availability and physician-to-population ratio estimates from Area Health Resource File, and linked them to the county-level BRFSS data. The dependent variable was the proportion using dental services within the last year in each county (ranging from 16.6% to 91.0%). We described the association between dental workforce availability and dental services utilization using ordinary least squares regression and spatial regression techniques. Spatial analyses consisted of bivariate Local Indicators of Spatial Association (LISA) and geographically weighted regression (GWR). Results Bivariate LISA showed that counties in the central and southern Appalachian regions had significant (p dental workforce availability, low percent dental services utilization). GWR revealed considerable local variations in the association between dental utilization and dental workforce availability. In the multivariate GWR models, 8.5% (t-statistics >1.96) and 13.45% (t-statistics >1.96) of counties showed positive and statistically significant relationships between the dental services utilization and workforce availability of dentists and dental hygienists, respectively. Conclusions Dental workforce availability was associated with dental services utilization in the Appalachian region; however, this association was not statistically significant in all counties. The findings suggest

Plumage reflectance is not affected by preen wax composition in red knots Calidris canutus

NARCIS (Netherlands)

Reneerkens, J; Korsten, P

It has recently been shown that sandpipers (Scolopacidae) abruptly switch the chemical composition of their preen gland secretions from mono- to diester waxes just before the period of courtship. The timing and context of the shift suggested that diesters could provide a visible quality signal

In search of low cost biological analysis: Wax or acrylic glue bonded paper microfluidic devices

KAUST Repository

Kodzius, Rimantas

2011-01-01

In this body of work we have been developing and characterizing paper based microfluidic fabrication technologies to produce low cost biological analysis. Specifically we investigated the performance of paper microfluidics that had been bonded using wax o

In search of low cost biological analysis: Wax or acrylic glue bonded paper microfluidic devices

KAUST Repository

Kodzius, Rimantas

2011-11-04

In this body of work we have been developing and characterizing paper based microfluidic fabrication technologies to produce low cost biological analysis. Specifically we investigated the performance of paper microfluidics that had been bonded using wax o

Open source and healthcare in Europe - time to put leading edge ideas into practice.

Science.gov (United States)

Murray, Peter J; Wright, Graham; Karopka, Thomas; Betts, Helen; Orel, Andrej

2009-01-01

Free/Libre and Open Source Software (FLOSS) is a process of software development, a method of licensing and a philosophy. Although FLOSS plays a significant role in several market areas, the impact in the health care arena is still limited. FLOSS is promoted as one of the most effective means for overcoming fragmentation in the health care sector and providing a basis for more efficient, timely and cost effective health care provision. The 2008 European Federation for Medical Informatics (EFMI) Special Topic Conference (STC) explored a range of current and future issues related to FLOSS in healthcare (FLOSS-HC). In particular, there was a focus on health records, ubiquitous computing, knowledge sharing, and current and future applications. Discussions resulted in a list of main barriers and challenges for use of FLOSS-HC. Based on the outputs of this event, the 2004 Open Steps events and subsequent workshops at OSEHC2009 and Med-e-Tel 2009, a four-step strategy has been proposed for FLOSS-HC: 1) a FLOSS-HC inventory; 2) a FLOSS-HC collaboration platform, use case database and knowledge base; 3) a worldwide FLOSS-HC network; and 4) FLOSS-HC dissemination activities. The workshop will further refine this strategy and elaborate avenues for FLOSS-HC from scientific, business and end-user perspectives. To gain acceptance by different stakeholders in the health care industry, different activities have to be conducted in collaboration. The workshop will focus on the scientific challenges in developing methodologies and criteria to support FLOSS-HC in becoming a viable alternative to commercial and proprietary software development and deployment.

Fruit development, pigmentation and biochemical properties of wax apple as affected by localized Application of GA3 under field conditions

OpenAIRE

Khandaker, Mohammad Moneruzzaman; Boyce, Amru Nasrulhaq; Osman, Normaniza; Golam, Faruq; Rahman, M. Motior; Sofian-Azirun, M.

2013-01-01

This study investigated the effects of gibberellin (GA3) on the fruit development, pigmentation and biochemical properties of wax apple. The wax apple trees were rubbing treated with 0, 20, 50 and 100 mgGA3/l under field conditions. The localized application (rubbing) of 50 mg GA3/l significantly increased the fruit set, fruit length and diameter, color development, weight and yieldcompared to the control. In addition, GA3 treatments significantly reduced the fruit drop. With regard to the fr...

Danish dental education:

DEFF Research Database (Denmark)

Moore, Rod

1985-01-01

The effects of Danish cultural traditions on dental education in Denmark are described, as well as the system's current structure and developing issues. Some Danish ideas for future exports of dental education programs and dental personnel are also discussed.......The effects of Danish cultural traditions on dental education in Denmark are described, as well as the system's current structure and developing issues. Some Danish ideas for future exports of dental education programs and dental personnel are also discussed....

Expanded function allied dental personnel and dental practice productivity and efficiency.

Science.gov (United States)

Beazoglou, Tryfon J; Chen, Lei; Lazar, Vickie F; Brown, L Jackson; Ray, Subhash C; Heffley, Dennis R; Berg, Rob; Bailit, Howard L

2012-08-01

This study examined the impact of expanded function allied dental personnel on the productivity and efficiency of general dental practices. Detailed practice financial and clinical data were obtained from a convenience sample of 154 general dental practices in Colorado. In this state, expanded function dental assistants can provide a wide range of reversible dental services/procedures, and dental hygienists can give local anesthesia. The survey identified practices that currently use expanded function allied dental personnel and the specific services/procedures delegated. Practice productivity was measured using patient visits, gross billings, and net income. Practice efficiency was assessed using a multivariate linear program, Data Envelopment Analysis. Sixty-four percent of the practices were found to use expanded function allied dental personnel, and on average they delegated 31.4 percent of delegatable services/procedures. Practices that used expanded function allied dental personnel treated more patients and had higher gross billings and net incomes than those practices that did not; the more services they delegated, the higher was the practice's productivity and efficiency. The effective use of expanded function allied dental personnel has the potential to substantially expand the capacity of general dental practices to treat more patients and to generate higher incomes for dental practices.

Radiographic Assessment of Dental Maturation in Children With Dental Agenesis.

Science.gov (United States)

Medina, Aida Carolina; Pozo, Rodrigo Del; de Cedres, Lucila Blanco