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Introduction: Anterior composite restorations present many aesthetic challenges for clinicians. Direct veneers provide chairside advantages such as evaluating tooth anatomy, shade selection, and correcting tooth morphology according to the patient's desire. In today's world, the use of digitalisation and 3D-printed models has grown. However, limitations of these are unknown and a research gap exists, with surface roughness being a major issue. Aim: To evaluate the surface roughness of clear silicon templates fabricated over 3D-printed models, blue inlay wax and dental stone. Materials and Methods: This in-vitro study utilised both quantitative and qualitative approaches. The study was conducted at the Department of Conservative Dentistry and Endodontics, Manubhai Patel Dental College and Hospital, Vadodara, Gujarat, India. The study was completed over three months. A total of 36 surfaces of clear silicone template (Exaclear) were obtained from two blocks each of 3D-printed model, blue inlay wax, and dental stone, measuring 30Ã--10Ã--10 mm. These blocks were divided into six units of 10Ã--5 mm (N=36) and were divided into three groups: 1) 3D-printed model; 2) Blue inlay wax; 3) Dental stone. Surface roughness was evaluated using a surface roughness tester and Scanning Electron Microscope (SEM). Quantitative analysis of surface roughness was done using the surface roughness tester, and qualitative analysis was done using SEM. Statistical analysis was done using the posthoc Tukey Honest Significant Difference (HSD) test and statistical software SPSS Version 20.0. Results: The quantitative analysis showed the highest Roughness average (Ra) value mean±Standard Deviation (SD) for Group 1 (11.97±4.43 μm), followed by Group 3 (2.42±1.07 μm) and Group 2 (0.63±0.86 μm). SEM showed the presence of voids only in Group 1. Conclusion: Surface roughness of clear silicon template fabricated on wax surface is less as compared to templates fabricated on 3-D printed models. [ABSTRACT FROM AUTHOR]

Introduction: Passive Microvolume Irrigation (PMI) with Sodium Hypochlorite (NaOCl) has been proposed as a new method for root canal disinfection. It is based on the concept that irregular surface characteristics of endodontic instruments can carry NaOCl into the canal space with controlled fluid volume, without applying any pressure. Aim: To compare and evaluate the efficacy of 3% and 5% NaOCl PMI, Saline PMI, and 3% NaOCl Standard Irrigation (SI) in removing the Smear Layer (SL) from the root canal walls at the cervical, middle, and apical thirds of single-rooted teeth. Materials and Methods: This study was conducted in the Department of Conservative Dentistry and Endodontics at Vishnu Dental College, Andhra Pradesh, India. The study was conducted in February 2018. Forty maxillary central incisors with a single canal, extracted within three months of the study, were collected. The teeth were divided into four groups (n=10) based on the irrigation method: Group-1 (3.0% NaOCl SI), Group-2 (3.0% NaOCl PMI), Group-3 (5.0% NaOCl PMI), and Group-4 (Saline PMI). All samples were instrumented upto F4 size with Protaper rotary files, and a final rinse of 17% Ethylenediaminetetraacetic Acid (EDTA) was used. SL removal was evaluated using Scanning Electron Microscope (SEM). The data were analysed using Statistical Package for Social Sciences (SPSS) 21.0. Statistical tests used were Kruskal Wallis and Mann-Whitney-U tests. A p-value of <0.05 was considered statistically significant for all comparisons. Results: There was no significant difference (p>0.05) in SL removal between 3.0% NaOCl SI, 3.0% NaOCl PMI, and 5.0% NaOCl PMI in the middle and apical thirds of the root canals. However, 5.0% NaOCl PMI showed significantly higher efficiency in SL removal at the cervical third compared to the other groups (p<0.05). Conclusion: Passive microvolume irrigation with 3% and 5% NaOCl showed comparable efficacy to 3% hypochlorite SI in the middle and apical thirds of the root canal. [ABSTRACT FROM AUTHOR]

With the recent upsurge in the construction of new ballasted railway tracks and their maintenance, the high requirement of ballast and subballast materials has become an important challenge. The use of industrial by-products in the construction of railroads can be an approach for the sustainable development of railway. With an increase in steel production, the generation of steel slag is also expected to increase at an alarming rate in India. At present, the utilization of this by-product of the steel industry is marginal; however, it has an enormous potential to be used in railroad construction. Therefore an attempt has been made to use steel slag as the subballast material in the present work. The objective of this study is to assess the strength and stiffness, leaching behavior, and mineralogical characteristics of the cement-stabilized steel slag (CSS) as a subballast layer and its implications in the design methodology. A series of laboratory tests such as compressive strength, splitting tensile, flexural strength, and flexural modulus tests were carried out on the CSS with four different (1%, 3%, 5%, and 7%) cement contents. In addition, X-ray diffraction (XRD) and scanning electron microscope (SEM) were also employed to examine the mineralogical characteristics. The results suggest that cement stabilizations lead to strength and stiffness gain along with resistance to the leaching of the trace metals such as arsenic, barium, cadmium, chromium, lead, and zinc. The results show the steel slag has the potential to be used as subballast material. A step-by-step design methodology suitable for cement-stabilized steel slag as a subballast layer has been proposed by modifying the existing Association of American Railroads (AAR) method along with a practical design example. [ABSTRACT FROM AUTHOR]

In India, during mining and ore processing, ore fine generation is a common phenomenon, in which more than 60% of process ore becomes discarded material. To explore the alternative of high-grade ores, mutual replacement with the utility of dump ore fines is the best way. With this perspective, Kiruburu iron ore mine (Iron Ore No.1) and Meghataburu iron ore mine (Iron Ore No.2) dumped fines were chosen for a Blaine no. investigation, in the connection of firing temperatures, to get optimum desirable physical properties, Cold Compression Strength (C.C.S.),and Apparent Porosity (A.P.), with physico-chemical properties, Reducibility Degradation Index (R.D.I.), and Reducibility Index (R.I.). To characterize pellet properties with input variables, a microstructure phase study has been conducted using a scanning electron microscope (S.E.M.), energy dispersive spectroscopy (EDS), and X-ray diffraction analysis (XRD). The Iron Ore No.1 and 2 fine pellets survey showed good, desirable properties, at the Blaine no., of 1678 cm2/g and 2311 cm2/g (corresponding to 200 mesh size), and the best results are attained at a firing temperature of 1300 °C. Thermal kinetic analysis of the heating of pellets has been done to knowthe activation energy of different ore characteristics. The results showed that Iron Ore No.2 pellets have high activation energy. [ABSTRACT FROM AUTHOR]

River sand samples have been collected from Ponnai river, Tamil Nadu, India for characterization of minerals and heavy metals by different spectroscopic techniques. Initially, the samples were subjected by Fourier Transform-Infra Red (FT-IR) spectroscopic technique and infra-red absorption bands values are observed in the range of 515–520, 695–700, 775–780 cm−1 which shows the presence of quartz in all the samples. Similarly, infra-red peaks were absorbed for feldspar, kaolinite, calcite, gibbsite and organic carbon and confirmed by X-Ray diffraction (XRD) technique. Additionally, zircon, aragonite, magnetite and kyanite minerals were identified in the samples using only the XRD method. The concentration of heavy metals such as Pb, Cr, Zn, Ni, Hg, As, Mn, Cu has been determined by flame atomic absorption spectrometry (FAAS). An average metal concentration measured in mg kg−1 were: Pb 0.12, As 0.15, Hg 0.13, Cu 2.80, Zn 10.15 Cr 12.70, Ni 2.86 and Mn 104.94 and hence found in the order of Mn > Cr > Zn > Ni > Cu > As > Hg > Pb. These average values do not exceed the world average value and hence potentially do not affect the quality of sand in the river. In addition to that, presences of heavy metals are confirmed by scanning electron microscope equipped with energy dispersive X-ray spectrometry (SEM/EDS) analysis. In order to understand the possible natural and anthropogenic sources of heavy metals, multivariate statistical techniques such as Pearson correlation, principal component and cluster analysis were performed. Results obtained from the statistical techniques were good agreement with each other. [ABSTRACT FROM AUTHOR]

This study aimed to analyze the seed coat structure of nine species from the genus Impatiens from Northeast India. A review of the available literature showed a scarcity of data on seed sizes and shapes, as well as a complete lack of information on the ultrastructure of seeds from five taxa of Impatiens determined with a scanning electron microscope (SEM). Photographs of the surface structure of seeds from the analyzed species were taken using an SEM and, from these, we measured the length and width of the seeds. The results showed differences in the seed ultrastructure and metric traits within the studied taxa. Based on the ornamentation of the epidermal cells, we distinguished three morphological types: protrusive, granulate, and reticulate. The seeds of the investigated species had ellipsoid, subellipsoid, or subspheroid shapes. Their lengths and widths ranged from 1.2 to 3.6 mm and 0.7 to 2.1 mm, respectively. The results of the study showed that the ultrastructures of Impatiens seeds are different among taxa and for some species can be used as a diagnostic character for their identification. [ABSTRACT FROM AUTHOR]

Andaman padauk (Pterocarpus dalbergioides Roxb.) is an important endemic tree species of the Andaman Islands, India, belonging to the family Fabaceae. We studied the seed microstructures which provide information on the physiological features of germination (i.e. factors responsible for the resumption of growth of embryo). Seed anatomy/morphostructures revealed information on its germination physiology (for ex situconservation), dormancy barriers and further taxonomical classification. The seed samples were examined under a scanning electron microscope (SEM) and Fourier-transform infrared spectroscopy (FTIR) was used to study the chemical composition of the seeds. In the SEM images, seed thickness of the parenchyma layer was about 53.16 μm, while that of the osteosclereids (OH) and macrosclereids (MH) layers was 23.95 and 84.68 μm respectively. The size of OS cells had a length of 25.81–34.56 μm; diameter 12.14–16.5 μm and width 7.97–12.60 μm. FTIR spectra of padauk seed assignments were used to determine the probable chromophoric groups that are likely to be present in the seeds. Various functional groups such as N–H, O–H, C–H, C=O, C–O were identified in the seeds. The results indicate the presence of carbohydrates, amino acids, amides, esters, ethers, phenols, proteins and fats in the padauk seeds. These observations would be helpful in correlating several aspects of seed germination/dormancy physiology of this endemic species, which has applications in ex situ conservation. [ABSTRACT FROM AUTHOR]

Kachchh Basin is well known for its Jurassic sediments and hydrocarbon prospects, but geochemically, these sediments remained less explored. Here, we present petrography, mineralogy, and geochemistry of the Middle Jurassic sandstone and shale of the Chari Formation exposed at Jumara Dome, Kachchh Basin, to understand their provenance, tectonic setting, source area weathering, and paleoclimate. Petrographic analysis shows that the sandstone consists of abundant quartz, feldspar (K‐feldspar and plagioclase), mica (muscovite and biotite), and lithic fragments. The X‐ray diffraction analysis of both sandstone and shale reveals the presence of abundant quartz, and lesser amount of kaolinite, illite, and chlorite. The presence of these clay minerals was also attested by scanning electron microscope analysis. Based on framework composition and geochemistry, the sandstone is classified as arkose to subarkose and shale as graywackes. Detrital modes and geochemical data suggest the derivation of these clastic rocks from a felsic source, partially influenced by sediment recycling and deposited in a passive margin setting in a rifted basin. Values of weathering indices including chemical index of alteration, plagioclase index of alteration, chemical index of weathering, and index of compositional variability indicate that the rocks of Jumara Dome are mature and the source area has undergone a moderate to high degree of chemical weathering under warm and humid climatic conditions. The petrography, bulk mineralogy, scanning electron microscope analysis, and geochemical composition in conjunction with paleocurrent data affirm the supply of detritus for Jumara Dome from the Aravalli Craton situated to the east and northeast and Nagar Parkar Massif situated to the north and northwest of the basin. This study endorses the formation of Transgondwanan seaway route during the Late Oxfordian, which caused a marine transgression onto the land. [ABSTRACT FROM AUTHOR]

This study included 21 newly isolated clinical samples of Streptococcus agalactiae (Group B Streptococcus) screened in patients (six male, fifteen female) from various states of India with different infections (urinary tract infections, blood, pus and eye infections). All isolates were identified as Group B Streptococcus (GBS) using hemolytic properties, serogrouping and MALDI-TOF-MS analysis. Six virulence genes, cfb (100%), cylE (90.4%), lmp (85.7%), bca (71.4%), rib (38%) and bac (4.7%) were detected via polymerase chain reaction (PCR). Distribution studies of these six genes revealed five isolates containing five virulence genes (23.8%), followed by ten isolates containing four virulence genes (47.6%). The twenty GBS isolates selected on the glass surface included non-biofilm producers (n = 6, 30%), weak (n = 11, 55%) and moderate biofilm producers (n = 3, 15%). On the polystyrene surface, weak (n = 4, 20%), moderate (n = 2, 10%) and strong (n = 14, 70%) biofilm producers were detected. Live-dead cell staining revealed that more viable cells accumulated in the S. ag 7420 isolate than in the AH1 isolate. Scanning electron microscope (SEM) biofilm analysis showed S. ag AH1 cells appeared as chain-like structures, whereas the S. ag 7420 isolate biofilm cells appeared as fork-like structures on the glass surface. Biofilm elements were analyzed using Energy Dispersive X-Ray Analysis (EDAX) for both isolates and 13 elements with different orders of composition were found. Thus, virulence gene detection, distribution and biofilm formation by these new clinical isolates suggested the virulent nature of these pathogens, which might cause different levels of disease severity in humans. [Display omitted] • A 21 GBS isolates were isolated from UTIs, blood, pus and eye infections. • GBS isolates were identified by hemolysis, serogrouping and MALDI-TOF-MS. • Detection and distribution of cfb, cylE , lmp , bca , rib and bac genes were analysed. • A 20 GBS isolates biofilms were analysed on glass and polystyrene surfaces. • Live-dead cell staining assay revealed more viable cells in S. ag 7420 than AH1 isolate. [ABSTRACT FROM AUTHOR]

Determination of urea in milk is inevitable in the dairy industry for the quality control processes. A simple and cost-effective method was developed to determine the concentration of urea in milk by silver nanoparticles (uncapped and citrate capped) and ultraviolet–visible (UV–Vis) spectroscopy. The developed nanoparticles were characterized by UV–Vis, scanning electron microscope (SEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy and a colour change was noted from yellow to blue upon nanoparticles interaction with urea. A predictive model was developed using the spectral data from the analyzed samples. The developed model was able to measure urea concentration (between 6 mg/dL to 90 mg/dL) in milk with the coefficient of determination (R2) more than0.90 and was validated through para -dimethylaminobenzaldehyde (DMAB) method suggested by the Food Safety and Standards Authority of India (FSSAI). The average accuracy and sample percent relative standard deviation (% RSD) obtained through the developed method + model ranged from 62.67 to 121.85% and 0.11–1.21%. The regression model for uncapped nanoparticles was found to be best-fitted (having R2 = 0.92, average accuracy 103.75 ± 8.69%), with higher closeness to the values obtained for urea by FSSAI-DMAB method. This proposed study proves to be useful for the qualitative and quantitative determination of urea in milk by small businesses in the dairy industry. • Detection of urea in milk through silver nanoparticles based UV-VIS spectroscopy. • Spectral data based development of predictive model for urea determination in milk. • The method is simple, cost-effective and beneficial for quality control of milk. [ABSTRACT FROM AUTHOR]

The East coast of India is subject to continuous changes by high energy events. We sought to assess the depositional conditions along the coast from the geophysical and sedimentological character of the dune sands of the Gopalpur and Paradeep coast of Odisha, and the Sagarnagar coast of North Visakhapatnam. Quartz layers of the heavy mineral-rich zone collected at a depth of ~2 m from the landward foot of the dunes in the Visakhapatnam and Odisha coast, gave the OSL age estimates as 1,050 ± 50 and 260 ± 10 years respectively, revealing that the age of the dunes in Visakhapatnam are older than those on the Odisha coast. Episodic high energy events have affected the coast. Evidence from ground penetrating radar data consists of three stratigraphic units. The upper unit consists of vague reflections, parallel to the ground in continuous manner, most probably formed by wind action. On the other hand, the middle layer shows high amplitude reflections of heavy mineral-rich massive layers, possibly the result of tsunami activity. The lower massive layer parallel to the ground surface shows a low reflection pattern. The GPR studies showed that the thickness of the heavy mineral layers is greater on the landward foot of the dune as compared to that on the seaward side. According to the grain size analysis, the dune is composed of both wind generated and tsunamigenic sediments. The scanning electron microscope studies revealed that the heavy minerals present in the dunes are mainly sillimanite, ilmenite, garnet, pyroxene, rutile, sphene, biotite, hornblende, zircon, monazite and magnetite. The study demonstrates the origin of sand dunes in different ages along the East Coast of India by the effect of various natural phenomena. [ABSTRACT FROM AUTHOR]

The mycofabricated metal nanoparticles (NPs) plays a significant role in cancer therapeutics and imparts a strategy in medicine. The current investigation focused to synthesize the Copper Oxide Nanoparticles (CuONPs) using an endophytic fungus isolated from Aegle marmelos a medicinal tree located in Western Ghats, India. The endophytic fungus FCBY1 explored the highest antagonistic and antioxidant activities among the 16 pigmented endophytic fungal strains which were isolated from the collected samples. The fungus FCBY1 was identified for its morphological and molecular characteristics where the (Internal Transcribed Spacer) ITS 1, 5.8 ribosomal gene and ITS 2 were sequenced; and the organism FCBY1 is Aspergillus terreus. The endophyte was put through for the synthesis of CuONPs and the size and structure of the synthesized particles were characterized by Scanning Electron Microscope (SEM). The confirmation of the CuONPs was characterized by FT-IR, EDAX and XRD analyses. The CuONPs exhibited the maximized antibacterial and antifungal activities against the human clinical pathogens; moreover the particles also explicated the free radicals/ROS scavenging at minimum concentration, which was assessed through DPPH, nitric oxide radical scavenging assays, and reductive power ability. The anti-cancer activity of CuONPs on colon cancer cell lines (HT-29) was evaluated by MTT (IC 50 : 22 μg/mL) and FACS analyses (32.11% cells gated in S phase of cell cycle). Angiogenesis inhibition in tumor cells was estimated through in vivo HET- CAM assessment and the highest concentration 60 μL tested inhibited the blood vessels at the percentage of 31.36% and 81.81%. The CuONPs explicated the anti-cancer activities in a concentration – dependent manner and the results of this investigation manifest the significant role of the CuONPs in cancer therapeutics. • Copper oxide nanoparticles were synthesized using Aspergillus terreus FCBY1. • Synthesized nanoparticles were characterized using FTIR, XRD and SEM. • Nanoparticles displayed antibacterial, antifungal and radical scavenging activities. • Anti-cancer properties of nanoparticles evaluated on HT-29 cell lines. • The inhibition of angiogenesis was assessed via in vivo HET- CAM assessment. [ABSTRACT FROM AUTHOR]

The genus Plesiophrictus is diagnosed and redescribed based on type material and additional specimens. The type species P. millardi (Pocock 1899) is redescribed. The genus Heterophrictus is revalidated, with H. milleti as type species. Heterophrictus differs from Plesiophrictus by the absence of serrula on maxillae and by having a rastellum on the chelicerae and stiff, spike-shaped setae on the prolateral coxae I. The significance of characters used in the taxonomy of both genera is discussed. [ABSTRACT FROM AUTHOR]

We report a state-of-the-art cathodoluminescence (CL) facility attached to a high-resolution scanning electron microscope (HRSEM), installed recently at the Saha Institute of Nuclear Physics, Kolkata for the study of opto-electronic properties of nanostructured materials. In this note, we present the technical details of such a CL-SEM facility along with some experimental results. We also demonstrate that the high spatial resolution spectroscopy and imaging capability of a CL-SEM system can be utilized as an ideal tool for nanophotonic research. [ABSTRACT FROM AUTHOR]

In the last decades, researchers have developed new materials to improve the quality of human life. Owing to the frequent occurrence of bone fractures, it is important to develop plate materials for the fixation of fractured bones. These plate materials have to be lightweight, compatible with human tissues and ought to allow stiffness. Natural fibers have the advantage that they are renewable resources and have marketing appeal. The Asian markets have been supplying natural fibers for many years, e.g., sisal, banana and roselle are common reinforcement in India. In this research, the fabrication of plate material from powdered natural fibers like sisal (Agave sisalana), banana (Musa sapientum) and roselle (Hibiscus sabdariffa), with bio-epoxy resin Grade 3554A and Hardner 3554B, using moulding method, is described. The present work deals with the prediction of flexural rigidity of the NFRP composite which is compared with that obtained using the ANSYS solution. They are found to be in good agreement. In this work, microstructure is scanned by the scanning electron microscope. The objective of this research was to utilize the advantages offered by renewable resources for the development of biocomposite materials based on biopolymers and natural fibers. In the future, this plate material externally coated with calcium phosphate and hydroxyapatite (hybrid) composite can be used for inside fixation and also external fixation of fractured bones. [ABSTRACT FROM AUTHOR]

The morphological characteristics of BC aggregates present in the soot and carbonaceous aerosol (CA) samples were investigated. The process of soot formation under laboratory conditions took into account the commonly used practice of burning fuel in the households in India. The fractal morphology was determined by using box counting algorithm and maximum projected area of the aggregates by using their digital electron microscopic images. Former provided the estimates of perimeter fractal dimension (PDf) of each aggregate, and later estimated the average density fractal dimension (DDf) of aggregate groups. Numbers of particles constituting the aggregates, using projected area approach, were significantly higher than the estimates based on pixel counting. The measured average diameter of the primary particles in aggregates, ranged between 24 and 57nm. The fractal dimensions, PDf, for the laboratory-generated soot aggregates varied from 1.36 to 1.88. The PDf for aggregates derived from diesel-vehicles and biomass burning showed significant variation: biomass, 1.27; diesel vehicle, 1.82 and 1.7. The size and the dimensions estimated for the free fall CA samples showed large deviation. The ratio L/R g (length/radius of gyration) for soot aggregates (gasoline, kerosene, diesel, mustard oil and hexane) ranged from 3.5 to 4.8. Surface morphology of these aggregates, using scanning electron microscope (SEM), showed the presence of spherical “charred cenosphere” like particles in gasoline and free fall aerosol aggregates. FTIR investigations revealed the presence of a large number of organic groups (OC) associated with carbonaceous aggregates present in soot and free fall aerosol samples. [Copyright &y& Elsevier]

Abstract: Large quantities of leachate-contaminated lateritic soil results from dump yards in the southwest coast of India. These dump yards receive large quantities of municipal solid waste which includes chemical, industrial and biomedical wastes. Large areas of land are currently being used for this purpose. An extensive laboratory testing program was carried out to determine the compaction characteristics and hydraulic conductivity of clean and contaminated lateritic soil. Batch tests were used to study the immediate effect of leachate contamination on the properties of lateritic soil. Contaminated specimens were prepared by mixing the lateritic soil with leachate in the amount of 5%, 10% and 20% by weight to vary the degree of contamination. The results indicated a small reduction in maximum dry density and an increase in hydraulic conductivity due to leachate-contamination. The change induced by chemical reaction in the microstructure of the soil was studied by scanning electron microscope before and after contamination of soil with leachate. The structure of the leachate contaminated soil sample appeared to be aggregated in scanning electron microscope analysis. The aggregated structure increases the effective pore space and thus increases the hydraulic conductivity. Fifty percent increase in hydraulic conductivity was observed for specimens prepared at standard Proctor density and mixed with 20% leachate. Compaction characteristics did not change much with the presence of leachate up to 10%. With 20% leachate the maximum dry density decreased slightly indicating excess leachate in the soil. However the changes are not significant. [Copyright &y& Elsevier]

This paper reports the findings of experimental studies with regard to some common engineering properties (e.g., grain size, specific gravity, compaction characteristics, and unconfined compression strength) of both low and high calcium fly ashes, to evaluate their suitability as embankment materials and reclamation fills. In addition, morphology, chemistry, and mineralogy of fly ashes are studied using scanning electron microscope, electron dispersive x-ray analyzer, x-ray diffractometer, and infrared absorption spectroscopy. In high calcium fly ash, mineralogical and chemical differences are observed for particles, >75 μm and the particles of <45 μm size. The mode and duration of curing significantly affect the strength and stress–strain behavior of fly ashes. The geotechnical properties of fly ash are governed by factors like lime content (CaO), iron content (Fe2O3) and loss on ignition. The distinct difference between self-hardening and pozzolanic reactivity has been emphasized. [ABSTRACT FROM AUTHOR]