Effect of whitening toothpaste on surface roughness and microhardness of human teeth: a systematic review and meta-analysis

Background: Whitening toothpastes exert a whitening effect on teeth through higher surface cleaning effectiveness resulting from the abrasive properties of the paste or specific chemical components. This systematic review and meta-analysis was conceptualized to examine the relationship between whitening toothpastes and surface roughness as well as microhardness of human teeth and to clarify the evidence base available around this relationship by conducting a systematic review and meta-analysis of studies in this topic area, looking at in vitro randomized control trials. Methods: Criteria for including studies in the review were done based on population, intervention, comparison, outcomes and study and studies were identified from electronic databases. Covidence® was used for data screening and data extraction. The CONSORT tool was used for checking relevant content and methodology used in each of the papers reviewed. Systematic review was done followed by meta-analysis, using Review Manager. Results: A total of 125 articles were obtained on key word search. After duplicate removal and title screening, 17 articles were eligible for full text review. Finally, 7 studies were included for systematic review and meta-analysis was conducted on 4 studies. The forest plot for surface roughness showed that that the meta-analytic effect was statistically significant with surface roughness value being higher in the intervention group. The forest plot for microhardness showed that the meta-analytic effect was statistically significant with the microhardness value being lesser in the intervention group. Conclusions: Although whitening toothpastes typically can lighten tooth color by about one or two shades, there is some evidence to show that these toothpastes also affect the mineral content of teeth by increasing surface roughness and reducing microhardness. More evidence and further research are needed to identify the type of whitening agent which will whiten the tooth effectively while maintaining the integrity of the tooth structure.

Особенности динамики струйного потока, генерируемого при поверхностном кипении жидкости на лазерном нагревателе

It was experimentally found that hot submerged jets appeared at laser induced nucleation boiling near the tip optical fiber placed in water exponentially decrease the velocity with the increasing of laser power (heat flux). This result was obtained for closed cylindrical cuvette where hot jets collided with walls slipped the cuvette boundary and transfer the heat. Obtained result is necessary to take into account at precise laser induced surface cleaning inside the closed volumes, for development of medical technologies of laser therapy of pathologically changed vessels, cysts, and for other applications.

Design and fabrication of smart ceiling mop with adjustable head

The Ceiling cleaning process is one of the tedious tasks ever which involves removing algae, mold, lichen, dust, and moss from the surface. Cleaning of the roof becomes very difficult when the height of the roof is very high also an excess human effort is required which also makes the labor feel discomfort, in addition to muscle pain. By considering all the above-discussed difficulties, we have developed a concept of a semi-automatic ceiling cleaning machine that is capable of cleaning dirt, grime, algae, etc. on the ceiling. Enabling the machine in accessing hard-to-reach areas on the ceilingsand at higher altitudes. To make the controlling of the machine user-friendly an electric drive is incorporated, such that a person with less technical knowledge can access it with high accuracy. The power source for the entire operation is provided with the help of a battery which is internally installed in the setup. As an added advantage, the multi-head system is implanted, using this our setup can be used as a traditional brush head, and by changing the vacuum head, the setup is capable of performing dust collection operations using vacuum pressure. To make a machine which will take care of the safety of persons, save time and also shouldn't damage false ceiling structure. This method of ceiling cleaning can be used in hotels, offices, etc. which will give a more appealing look. This method is suitable for small, medium as well as large-scale applications.

Quality assessment of baby wet wipes

A wet wipe is a commercial product made of a fibrous substrate impregnated with a lotion that often comes folded and individually wrapped for convenience. The present work relates to wet wipes’ composition to clean the baby’s body. Wet wipes were produced from two spunlace nonwoven fabrics consisting of polyester/viscose and a wetting solution. Objective performance evaluation was carried out to determine the efficiency of the wipes for manufacturing and end uses. The lotion formula comprising surfactants, a solubilizer, preservative compounds, perfumes, and mainly purified water is selected to deliver the intended benefits of a baby wet wipe. Besides, physical, mechanical characteristics, and moisture management parameters of the wet wipe fabrics were measured. Optimal lotion (oil–water emulsion) stirring conditions were illustrated using optical microscopy. Lotion foamability appears as an undesirable phenomenon upon the manufacturing of the wet wipe. A mixture design, an extreme vertices design, was used to study the influence of the compounds on the foam volume. The relative contribution of each compound in the lotion to generate bath foam was discussed. Because wet media are more effective than dry media for surface cleaning, the optimum wet pick-up ensuring the best wiping efficiency about of 83.2% was found to be about 3 g of lotion for 1 g of fabric. Assuming that a wipe sample could be performed in less than 3 min, it was also confirmed that the developed wipe remains effective with a moisture content of 242% and can be comparable with other commercial wipes.

INVESTIGATION OF THE INFLUENCE OF IMPROVED TECHNOLOGY OF PREPARATION OF WHEAT GRAIN FOR GRINDING ON ITS MICROBIOLOGICAL SAFETY INDICATORS

Качество и безопасность зерна выступает важным и обязательным объектом государственного регулирования и контроля. Рост количества опасных видов сорных растений, вредных насекомых и заболеваний зерновых культур привел к снижению качества зерновой массы, повышению ее микробиальной обсемененности. Важным этапом снижения микробиальной обсемененности зерна является его подготовка к переработке. Для повышения эффективности сепарирования и поверхностной очистки зерна пшеницы и снижения его микробиологической обсемененности учеными Кубанского государственного технологического университета предложена технологическая линия, включающая установку фотоэлектронного сепаратора перед овсюгоотборником для очистки зерновой массы от примесей, отличающихся от зерна пшеницы по цвету, и шлифовального агрегата вместо обоечных машин для очистки поверхности зерна. Цель настоящего исследования – определить эффективность применения предложенной технологии подготовки зерна пшеницы к помолу на примере его микробиологических показателей безопасности. В качестве объектов исследования были образцы зерна пшеницы из партий, поступивших с элеватора в подготовительное отделение мельницы, отобранные на зерноперерабатывающих предприятиях Краснодарского края, работающих как по традиционной, так и по усовершенствованной технологии. Установлено, что в зерновой массе, подготовленной к помолу по разработанной технологии, общее количество бактерий на 65% меньше, а содержание дрожжей и плесеней соответственно в 2 и 3 раза ниже, чем в зерновой массе, подготовленной к переработке по традиционной технологии. Из зерновой массы, подготовленной к переработке по усовершенствованной технологии, были полностью удалены вредные и минеральные примеси, фузариозные зерна и куколь. Результаты исследования показали высокую эффективность применения разработанной технологии подготовки зерна пшеницы к помолу. The quality and safety of grain is an important and mandatory object of state regulation and control. The increase in the number of dangerous species of weeds, harmful insects and diseases of grain crops has led to a decrease in the quality of grain mass, an increase in its microbial contamination. An important step in reducing the microbial contamination of grain is its preparation for processing. To increase the efficiency of separation and surface cleaning of wheat grain and reduce its microbiological contamination, scientists of the Kuban State Technological University have proposed a technological line that includes the installation of a photoelectronic separator in front of the oat collector to clean the grain mass from impurities that differ from wheat grain in color, and a grinding unit instead for cleaning the grain surface. The purpose of this study is to determine the effectiveness of the proposed technology for preparing wheat grain for grinding on the example of its microbiological safety indicators. The objects of the study were samples of wheat grain from batches received from the elevator to the preparatory department of the mill, selected at grain processing enterprises of the Krasnodar region operating both according to traditional and improved technology. It was found that in the grain mass prepared for grinding according to the developed technology, the total number of bacteria is 65% less, and the content of yeast and mold respectively is 2 and 3 times lower than in the grain mass prepared for processing according to traditional technology. Harmful and mineral impurities, fusarium grains and Agrostemma L. were completely removed from the grain mass prepared for processing using improved technology. The results of the study showed the high efficiency of the application of the developed technology for preparing wheat grain for grinding.

Plasma excited molecular beam epitaxy－proposal and achievements through R&D of compound semiconductor materials and devices－

This paper reviews 35 years of brief history on plasma-excited molecular beam epitaxy, focusing on special values added to conventional Molecular Beam Epitaxy (MBE) through usage of plasma-excited molecular beams. These include low temperature surface cleaning, low temperature growth, selected area re-growth and impurity doping. These technologies are extremely important to realize nano-scale low-dimensional device structures. InN and In-rich InGaN are also highlighted as unique material systems, which plasma-excited MBE process is inevitable to grow. Future prospect of this technology will also be included from the device application viewpoints.