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Veerasamy Ravichandran and Rajak Harish

Abstract

The main objective of the present study was to establish significant and validated QSAR models for imidazoles and sulfonamides to explore the relationship between their physicochemical properties and antidiabetic activity. Two dimensional QSAR models had been developed by multiple linear regression and partial least square analysis methods, and then validated for internal and external predictions. The established 2D QSAR models were statistically significant and highly predictive. The validation methods provided significant statistical parameters with q2 > 0.5 and pred_r2 > 0.6, which proved the predictive power of the models. The developed 2D QSAR models revealed the significance of SlogP and T_N_O_5, and Mol.Wt and SsBrE-index properties of imidazoles and sulfonamides on their antidiabetic activity, respectively. These results should prove to be an essential guide for the further design and development of new imidazoles and sulfonamides having better antidiabetic activity.

Open access

Serap Ayaz Seyhan, Cağlar Demirbağ and Emre Dölen

Abstract

Dyer’s kermes (Kermes vermilio) is found only on the kermes oak (Quercus coccifera L). They were used in the past for the preparation of dyes for textiles and as a pharmaceutical. The main constituents of this insect are kermesic acid (ka) and flavokermesic acid (fk). Historically and culturally important dyer’s kermes insect red dyes were investigated by high performance liquid chromatography. Kermes in the Northwest of Turkey were analyzed first time the relative amount of the dyestuffs although their presence has been reported analytical works related to this insect. The relative amount in the acid hydrolyzed extract of Kermes vermilio from the Northwest of Turkey looked very similar to the France.

Open access

Saba Manzoor, Nisar Fatima, Akhlaq Ahmad Bhatti and Akbar Ali

Abstract

The first Zagreb index (occurred in an approximate formula of total π-electron energy, communicated in 1972) and the second Zagreb index (appeared in 1975, within the study of molecular branching) are among the most studied topological indices. Recently, three modified versions of the Zagreb indices were proposed independently in [A. Ali, N. Trinajstić, A novel/old modification of the first Zagreb index, arXiv:1705.10430 [math.CO], 2017] and [A. M. Naji, N. D. Soner, I. Gutman, On leap Zagreb indices of graphs, Commun. Comb. Optim., 2017, 2, 99–117], which were named as the Zagreb connection indices and the leap Zagreb indices, respectively. In this paper, we derive formulas for calculating these modified versions of the Zagreb indices of four well known nanostructures.

Open access

Ade Kartikasari Sebba, Baning Rahayujati and Isa Dharmawidjaja

Abstract

Pneumonia is one of the deadliest diseases for children under five years-old throughout the world. In Indonesia, pneumonia is the second deadliest disease after diarrhea. In 2015-2016, the Coverage of pneumonia case detection on children under five years-old increased from 22.33% to 36.06% but it had not achieved the detection target (>85%). A program evaluation needs to conduct, consequently. The evaluation aims to observe the implementation of pneumonia investigation program on children under five years-old in Sleman in 2016. The evaluation used a descriptive design performed in June-July 2017. The research subject was the program of Upper Respiratory Infection (ISPA, Infeksi Saluran Pernapasan Akut) implemented in community health centers (puskesmas, pusat kesehatan masyarakat). Twenty respondents as the sample were chosen by using the purposive sampling technique. The surveillance evaluation employed the input, activities, and output. The instruments were structural questionnaires and checklist sheets. The analysis result was presented in forms of tabulation and narration. From the input facet, 100% respondents have not had any special trainings related to pneumonia. 55% respondents have interlocking jobs with the longest service time of three years or more (75%). 70% respondents are able to show ARI Soundtimer. There are only 10% respondents holding the media of communication, information, and education (KIE, Komunikasi, Informasi, dan Edukasi) in forms of flipchart and leaflet; while 100% respondents admit that they have no stamp seal of URI. The proses facet displays that 100% respondents do not arrange any plan. The case investigation is only passive (100%). 80% respondents do socialization of case management and only 15% respondents perform a home visit. 100% respondents have not held trainings for responsible people, alert villages, and private midwives. From the output facet, the scope of case investigation is still low (36.06%).The implementation of pneumonia case investigation program on children under five years-old has been well executed but there are still weaknesses. Hence, public health offices (dinas kesehatan) should improve their human resources by arranging a training program, equalize the use of breath counting tool and make MoU with all health services to report pneumonia cases. Community health centers are recommended to arrange plans, actively attempt to discover pneumonia cases, and train the responsible people, centers for pre-and postnatal health care (posyandu, pos pelayanan terpadu), or midwives related to the subject of pneumonia.

Open access

Andrzej Nowak

Abstract

Amazing is the fact that although the organisms have been known since the end of the seventeenth century, effective study of this group of organisms started after about 160 years, in the last two decades of the nineteenth century. The origins of science about bacteria were very difficult, there were many unknowns and conflict information. The research results provided by various scientists created complete chaos. From today’s perspective, it is difficult to imagine how it was possible, do research in such conditions, and obtain reliable results? Yet despite these difficulties, knowledge of our predecessors was neither so small nor so doubtful as might be supposed. On the contrary, it was surprisingly big and wide. What our predecessors knew about bacteria and especially their importance in nature? They knew that bacteria live everywhere, knew about their unlimited spread in the biosphere. The role of microorganisms in the mineralization of organic matter was known, as well as the circulation of matter in nature and role of bacteria in cycles of nutrient elements, and the solar energy as the driving force behind these changes. Today - although we understand these mechanisms much more accurately, we know a lot details and individual changes - but the basic outline of the functioning of the biosphere, valid until today created our predecessors. A look back at the beginning of the microbiology teaches us, how much can be achieved with seemingly primitive methods, if accompanied by a passion for research and imagination.

Open access

Zbigniew A. Szydło

Abstract

John Read and James Partington were both prominent and highly respected academics, chemists, authors and teachers during the middle decades of the 20th century. Their books were widely read throughout this period and played a major role in educating and raising the awareness of chemistry among young people and adults. Today their names are forgotten. The aim of the present article is to re-establish these two remarkable men and to bring them to the forefront of educational programs. An outline is given of their careers as chemists, set against the background of the times they lived in, giving an emphasis to their formidable literary output. Although they had widely contrasting personalities, and were specialists in three different fields of chemistry, Read: organic, Partington: physical and inorganic, they both recognized the great importance of setting chemistry in an historical context. Accordingly, they both wrote many works on the origins and development of chemistry and included much historical material in their textbooks. This added not only a great interest to the subject, but also set it in a broader cultural context, which is so clearly lacking in today’s chemistry teaching programs. A chronological list of their books is given and short contrasting fragments from four of them are analysed. Not only are these books of great interest, but they serve as an outstanding foundation for teaching the principles of chemistry today. A recommendation is made to incorporate one work of each author as compulsory reading material for students today, and in future years.

Open access

Diana Carmen Mirila, Mădălina-Ștefania Pîrvan, Nicoleta Platon, Ana-Maria Georgescu, Valentin Zichil and Ileana Denisa Nistor

Abstract

In this work, the advanced decomposition of organic dyestuffs used in food and textile industry, such as Malachite Green (MG), was investigated in the presence of a cationic catalyst montmorillonite (P1-PILCs) prepared by ion-exchange method. The obtained material was characterized by BET, FTIR and XRD. The effects of different variables such as: catalyst dose, catalyst/ozone dose, ozonation time and the pH on the mineralization of the synthetic dye were studied and optimal experimental conditions were ascertained. Compared with simple ozonation, the introduction of the catalyst greatly reduces the duration of the process to reach over 95% yield from 110 minutes to some seconds.

Open access

Lucian G. Bahrin

Abstract

The synthesis of 4-(2-hydroxyaryl)-5-methyl-1,3-dithiol-2-thiones has been accomplished by the reaction of the corresponding 4-(2-hydroxyaryl)-5-methyl-1,3-dithiol-2-ylium perchlorates with sodium sulfide nonahydrate in ethanol at room temperature. The newly obtained derivatives were characterized by NMR and MS spectrometry and IR spectroscopy.

Open access

Shashidhargouda H. R. and Shridhar N. Mathad

Abstract

This paper describes synthesis and structural properties of Ni0.45Cu0.55Mn2O4 nanopowder, obtained by co-precipitation route. XRD pattern reveals cubic structure with lattice parameter 8.305 Å. We report crystallite size (D), micro strain (ε), dislocation density (ρD), and hopping lengths (LA and LB). We also report preferential orientation by texture coefficients [Tc (h k l)]. The Williamson-Hall plot and stress-strain plot also employed to understand the mechanical properties of materials.