Quality assurance and authentication of herbal drug (Argyrolobium roseum and Viola stocksii) through comparative light and scanning electron microscopy

The quality assurance and authentication of crude herbal drugs play important role in the effective therapeutic effect of herbal drug and their products. There are many reported problems in quality assurance of herbal crude drugs concerning to their correct identification. The present study was designed with the aim to document the authentication and quality assurance of the herbal crude drugs (Argyrolobium roseum and Viola stocksii) thorough light microscopy (LM) and scanning electron microscopy (SEM). The detailed foliar anatomical studies showed polygonal epidermal cells having anticlinal walls in Argyrolobium roseum while rounded epidermal cells were observed in Viola stocksii. The anomocytic stomata type was observed in Argrolobium roseum while actinocytic was noticed in Viola stocksii. The pollen of studied species appeared as tricolporate showing reticulate exine sculpturing in Argrolobium roseum while fine perforations were recorded in Viola stocksii. Furthermore, quantitative analysis of phenols, flavonoids, and antioxidant activity showed high flavonoid and phenol content in Argyrolobium roseum as compared with Viola stocksii. It was observed that Argyrolobium roseum was discriminated from the Viola stocksii based on the leaf and pollen micromorphological traits by using LM and SEM techniques. It was concluded that LM and SEM techniques were found useful for the quality assurance of botanicals and their authentication.     

Comparative light and scanning electron microscopy in authentication of adulterated traded medicinal plants

The medicinal plants are utilized globally considering the cheap and chemical free source, but their correct identification and authentication is prerequisite for safety and efficacy of plant‐based medicines. The present study encompassed traded medicinal plants (16) with high therapeutic value from diverse families like Brassicaceae, Berberidaceae, Malvaceae, Salicaceae, Myrtaceae, Papilionaceae, Ascelpiadaceae, Colchicaceae, Violaceae, and Vitaceae for detailed microscopic study of characters that is, morphology, pollen shape and sizes, P/E ratio, pore length and width, spine length, colpi dimensions, and exine sculpture pattern. The plants showed noteworthy differences in microscopy of Wattakaka volubilis having pollinia, translator and corpusculum like structures while pores were visible in Colchicum luteum, Alcea rosea, and Hibiscus syriacus. The spines were observed in Centipeda minima, A. rosea, and H. syriacus being dimorphic spines in A. rosea and monomorphic in H. syriacus. The exine sculpturing pattern was reticulate in mostly studied plants however distinctive exine pattern was noted in Berberis aristata and Berberis lyceum. The highest polar diameter, equatorial diameter and exine thickness among studied plants were observed in H. syriacus (161 μm), C. luteum (50 μm) and Vitis jacquemontii (1.10), respectively. Thus, microscopy of medicinal plants in addition to other taxonomic evidence offers a supportive skill in authentication, consequently utilization by local consumers and pharmaceutical industries.     

Compatibilization of PLA/PBAT blends by using Epoxy-POSS

Poly(lactic acid) (PLA)/poly(butylene adipate-co-terephthalate) (PBAT) blends were compatibilized using epoxidized polyhedral oligomeric silsesquioxanes (Epoxy-POSS). Three different Epoxy-POSS types were utilized having mono-, tri-, and multi-epoxides per POSS cage. In order to understand the localization of Epoxy-POSS types, wetting coefficients were calculated from surface energy measurements. According to scanning electron microscopy (SEM) and transmission electron microscopy (TEM), it was observed that Epoxy-POSS types mostly located at the interface of PLA/PBAT phases. The compatibilization of PLA and PBAT was shown through the decrease in dispersed particles size and the shifts in glass transition temperatures of phases. Mechanical properties of PLA/PBAT improved in the presence of Epoxy-POSS types. The Izod impact strength and elongation in tensile test values were maximized when 0.5% monoepoxy-POSS was used as compatibilizer. The reactions between Epoxy-POSS and polymers were monitored by Fourier transform infrared (FTIR) analysis and rheology. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47217.     

Daylight availability in Turkey

In Turkey, daylight availability data are lacking, but solar radiation data for various climatological regions have been collected regularly at meteorological stations for more than 40 years. These solar radiation data can be converted into equivalent daylight illuminance data if the luminous efficacy of solar radiation is understood.For the purpose of determining the luminous efficacy of solar radiation, an apparatus capable of simultaneously measuring exterior daylight illuminance and solar radiation was installed in the observation park of the State Meteorological Office of Ankara in 1980.The data collected during a two-year period are evaluated by a computer program, and the hourly variation of monthly, seasonal, and annual means of luminous efficacy of solar radiation are calculated, By using these values, the available solar radiation data for previous years are converted into equivalent daylight illuminance data.In this paper the hourly variation of luminous efficacy values, daylight illuminance data, and the percentages of occurrence of various illuminance levels are tabulated. The results presented here may be used to predict a design base daylight illuminance level and the possible energy savings from photoelectric control of artificial lighting installations.More reliable daylight availability data will be obtained from evaluating at least five years of records. This computer analysis will be updated each year that data are collected.     

Relaxin-like factor expression as a marker of differentiation in the mouse testis and ovary

Expression of the relaxin-like factor (RLF) was studied at the messenger RNA (mRNA) and protein levels in the testes and ovaries of the mouse, as well as through testicular development and differentiation in the mouse testis. In situ hybridization or RT-PCR, and immunohistochemistry using a polyclonal antibody raised against a recombinant protein, provided mutually confirmatory results for a high expression of RLF in the Leydig cells of the adult testis and at a much lower level of expression in the luteal cells of the ovary through the cycle, pregnancy, and in lactation. Analysis of protein and mRNA expression, through postnatal testicular development, indicated moderate RLF expression also in the fetal population of Leydig cells, even in the hpg mutant mouse, lacking an active pituitary-gonadal axis. Prepubertal Leydig cells, however, exhibit only very low-level RLF gene expression, this phenotype persisting in the adult hpg mouse. In summary, fetal Leydig cells express RLF in an LH/human CG-independent fashion, whereas LH/human CG is essential to induce RLF expression in the adult-type Leydig cell. In cultured adult Leydig cells or in the mouse tumor MA-10 cell line, RLF mRNA is expressed in a constitutive fashion. RLF thus seems to be a useful marker of Leydig cell differentiation status.     

Effect of femtosecond laser beam angle and formed shape on surface roughness and shear bond strength between zirconia and resin cement

Achieving adhesion between resin cement and zirconia requires pretreatment of the surface. This in vitro study aimed to evaluate the effect of femtosecond laser beam angle and the shape of the formed surfaces, on the roughness and shear bond strength (SBS) of resin cement to zirconia ceramic. Seventy Y-TZP ceramic specimens were divided into seven groups (n = 10). A femtosecond laser irradiation was performed on the ceramic surface of three shapes (spiral (SP), square (SQ) and circular (CI) and at two angles (30 and 90°) to give SP-30, SQ-30 and CI-30 and SP-90, SQ-90 and CI-90, respectively. After treatment, the surface roughness of all specimens was evaluated using a profilometer. One specimen from each group was analysed using a scanning electron microscope. The bonded specimens were thermocycled 5000 times and then an SBS test was performed. Kruskal-Wallis and Mann-Whitney U tests were used to analyse surface roughness and SBS values. The control group had statistically lower surface roughness (R_a) values than the treated groups (p < 0.05). SP-30 and SQ-30 laser treated specimens showed higher R_a values than the other specimens. Statistically significant SBS values (p = 0.000) were observed between the groups. All laser treated samples showed greater SBS compared to the control group. SP-30, SQ-30 and SQ-90 groups showed the highest SBS values. Within the limitations of this experimental study, the highest mean values for R_a and SBS were achieved with SP and SQ surfaces using a 30° angle laser beam.     

Numerical comparison of methods for solving fractional differential–algebraic equations (FDAEs)

In this paper, the variational iteration method (VIM) and the Adomian decomposition method (ADM) are implemented to give approximate solutions for fractional differential–algebraic equations (FDAEs). Both methods in applied mathematics can be used as alternative methods for obtaining analytic and approximate solutions for different types of fractional differential equations. This paper presents a numerical comparison between these two methods and the homotopy analysis method (HAM) for solving FDAEs. Numerical results reveal that the VIM and the ADM are quite accurate and applicable.     

Investigation of carbon contamination in lost foam castings of low carbon steel

Lost foam casting(LFC) process is a special casting method in which polymeric foam patterns with refractory coatings are utilized as a mould component. In this work, four types of foam: expandable polyethylene(EPE), expandable polypropylene(EPP) and expandable polystyrene(EPS) foams with two different densities were employed as pattern materials. LFC and conventional green sand mould casting methods were used to cast a low carbon steel, A216 Grade WCB. Both casting processes were carried out at 1,580 °C. Chemical analysis results showed that the carbon contamination level was high and was influenced by pattern type. Metallographic investigations revealed a significant increase in the percentage of pearlite phase in all LFC samples. Densities of manufactured samples were calculated in order to evaluate porosity of the products. It was determined that the densities of the LFC samples were lower than the green sand mould cast reference sample(RS). Vickers hardness tests were also carried out and increments in hardness values with increased carbon content was observed.