New photo-luminescent inorganic materials: high-tec application in chemical sensing and labeling

This thesis describes the potential of various kinds of luminescent nanoparticles with respect to chemical sensing and biosensing. First, fluorescent silica nanoparticles (SiNPs) were prepared by covalent attachment of fluorophores to the amino-modified surface of SiNPs with a typical diameter of 15 nm. The SiNPs were used in novel kinds of Förster resonance energy transfer (FRET)-based affinity assays at the interface between nanoparticle and sample solution. Various labels were employed to obtain a complete set of colored SiNPs, with excitation maxima ranging from 337 to 659 nm and emission maxima ranging from 436 nm to the near infrared (710 nm). The nanoparticles were characterized in terms of size and composition using transmission electron microscopy, thermogravimetry, elemental analysis, and dynamic light scattering. The surface of the fluorescent SiNPs was biotinylated, and binding of labeled avidin to the surface was studied via FRET in two model cases. Secondly, the upconverting luminescent nanoparticles (UCLNPs) consist of hexagonal NaYF4 nanocrystals doped with trivalent rare earth ions were synthesized by both the oleic acid (solvothermal) method and the ethylenediaminetetraacetic acid (coprecipitation) method. The nanoparticles were codoped using Yb3+ as the sensitizer ion, Er3+, Tm3+, or Ho3+ respectively as the emitting activator ions. An affinity system was demonstrated based on the interaction of two types of nanoparticles. The first type consists of UCLNPs of the type NaYF4:Yb,Er absorbing light in the infrared and showing green luminescence at 521 and 543 nm and red luminescence at 657 nm. The second type consists of gold nanoparticles (Au-NPs) with a size of about 50 nm, which absorb the green luminescence of the UCLNPs, but do not influence their red luminescence. A model system for a self referenced affinity system were established by labeling the UCLNPs with avidin and the AuNPs with biotin. In the presence of avidin-modified UCLNPs, the biotinylated Au-NPs can be detected in the range from 12 to 250 µg•mL-1 by rationing the intensity of the red (analyte-independent) emission band to that of the green (analyte-dependent) emission band. All nanoparticles were characterized in terms of size and composition using transmission electron microscopy, thermo-gravimetry, and FTIR spectroscopy. Thirdly, different types of nanoparticles (made from silica, polystyrene and UCLNPs) carrying longwave absorbing and emitting fluorescent labels were prepared by conjugating reactive dyes to the surface of amino-modified particles. The dyes have a reactive chloro group capable of reacting with amino groups and thereby undergoing a change in color, typically from green to blue (the so-called chameleon effect). The latter show the effect of upconversion in that near-infrared laser light is converted into visible luminescence. They also show the unusual property of displaying dual emission, depending on whether their luminescence is photoexcited with visible light or near-infrared light. The amino groups on the surface of nanoparticles were detected via the chameleon effect of the applied amino-reactive dyes. Fourth, the quenching effect of heavy metal ions and halide ions on the luminescence of UCLNPs in aqueous solution was studied. The effect was investigated for the ions Cu(II), Hg(II), Pb(II), Cd(II), Co(II), Ag(I), Fe(III), Zn(II), bromide and iodide, and was found to be particularly strong for Hg(II). Stern-Volmer plots were virtually linear up to 10 – 25 mM concentrations of the quencher, but deviate from linearity at higher quencher concentrations where static quenching caused an additional effect. The UCLNPs display two main emission bands (blue, green, red or near-infrared), and the quenching efficiencies for these found to be different. The effect seems to be generally associated with UCLNPs because it was observed for all particles doped with trivalent lanthanide ions including Yb(III), Er(III), Ho(III), and Tm(III)

Antioksidativno djelovanje metanolnih ekstrakata listova sedam egipatskih vrsta roda Cassia

In the present study, antioxidant activity of methanolic extracts of the leaves of seven Egyptian Cassia species was investigated using two methods, the phosphomolybdate method and 1,1 diphenyl-2-picrylhydrazyl radical (DPPH•) scavenging activity method. The results revealed that C. glauca is the most potent species and that the activity of other plant species decreases in the following order C. grandis > C. nodosa > C. fistula > C. didymobtrya > C. occidentalis > C. sophera. Defatted methanolic extract of the most active plant C. glauca was subjected to fractionation process using different organic solvents such as CHCl3, EtOAc and BuOH. Antioxidant activities of these fractions were investigated and the results showed that ethyl acetate fraction possessed high activity. Total phenolic and flavonoid concentration of each plant extract were determined using the Folin-Ciocaltu reagent and aluminum chloride. Correlation between radical scavenging capacities of extracts and total phenolic concentration was observed.U radu je ispitano antioksidativno djelovanje metanolnih ekstrakata listova sedam egipatskih vrsta roda Cassia koristeći fosfomolibdatnu metodu i metodu vezanja slobodnih 1,1-difenil-2-pikrilhidrazil radikala (DPPH.). Rezultati pokazuju da C. glauca ima najveću aktivnost te da se djelovanje smanjuje sljedećim redom: C. grandis C. nodosa C. fistula C. didymobtrya C. occidentalis C. sophera. Odmašćeni metanolni ekstrakt najaktivnije biljke C. glauca frakcioniran je pomoću različitih organskih otapala kao što su CHCl3, EtOAc i BuOH. Ispitivanje antioksidativnog djelovanja pojedinih frakcija pokazuje da je etil-acetatna frakcija najaktivnija. Pomoću Folin-Ciocaltuovog reagensa i aluminijevog klorida određena je ukupna koncentracija fenola i flavonoida svakog pojedinog ekstrakta. Uočena je korelacija između sposobnosti hvatanja slobodnih radikala i ukupnog sadržaja fenola

A Generalized Skew of type IV Logistic Distribution

In this paper, we derive, the probability density function (pdf) and cumulative distribution function (CDF) of the skew type IV generalized logistic distribution GSLD IV . The general statistical properties of the GSLD IV . such as: the moment generating function (mgf), characteristic function (ch.f), Laplace and fourier transformations are obtained in explicit form. Expressions for the nth moment, skewness and kurtosis coefficients are discussed. The mean deviation about the mean and about the median are also obtained. We consider the general case by inclusion of location and scale parameters. The results of Asgharzadeh (2013) are obtained as special cases. Graphically illustration of some results have been represented. Further we present a numerical example to illustrate some results of this paper. Keywords: skew type IV generalized logistic distribution, moment generating function, skewness, kurtosis, mean deviation

Partial Replacement of Cement by Solid Wastes as New Materials for Green Sustainable Construction Applications

The manufacturing of ordinary Portland cement is an energy-intensive process that results in pollution and CO2 emissions, among other issues. There is a need for an environmentally friendly green concrete substitute. Waste products from a variety of sectors can be recycled and used as a green concrete substitute. This decreases the environmental effects of concrete manufacturing as well as energy consumption. The use of solid waste materials for green building is extremely important now and in the future. Green concrete is also in its infancy in terms of manufacturing and application. Academics must intervene by encouraging business implementation. The aim of this review paper is to raise awareness about the importance of repurposing recycled materials and to highlight new technologies for producing green, sustainable concrete

Diagnosing and treating esophageal obstruction in camels (Camelus dromedarius)

Background and Aim: Esophageal obstruction is a common occurrence and a serious condition in camels. This study aimed to assess the effects of mineral deficiency on esophageal obstruction rates in dromedary camels and describe their clinical presentation and treatment outcomes. Materials and Methods: Twenty-eight camels were allocated to two groups. Group 1 (control) was composed of 10 sound camels. Group 2 included 18 camels with esophageal obstruction which were based on clinical and imaging evaluations. Hematobiochemical examinations in control and affected camels were compared and statistically analyzed. Results: In camels with esophageal obstruction when compared with controls, hematological analyses showed significant increases (p < 0.05) in neutrophils, lymphocytes, and monocytes, along with significantly decreased total white blood counts. Aspartate transaminase, alanine transaminase, alkaline phosphatase, creatine phosphokinase, glucose, albumin, creatinine, and blood urea nitrogen concentrations were significantly higher in affected camels when compared with controls. Furthermore, gamma-glutamyl transferase, globulin, sodium, chloride, cobalt, iron, manganese, and selenium concentrations were significantly reduced. Affected camels were treated by stomach tube or surgery and were completely recovered, except for one camel with an esophageal fistula. Conclusion: A lack of trace elements could have a significant role in esophageal obstruction in dromedaries. Clinical, ultrasonographic, and hematobiochemical evaluations are useful for the accurate diagnosis, prognosis, and treatment of esophageal obstruction in camels

1,2,4-Triazine Chemistry Part I: Orientation of cyclization reactions of functionalized 1,2,4-triazine derivatives

Orientation of heterocyclization reactions of functionalized 1,2,4-triazines were studied by effect of substituents in 1,2,4-triazine moieties, type of the solvent used in the reaction and the temperature effect. Also, it was found that cyclization process depended mainly on the chemoselective and regioselectivity states of the parent substrate as well as preferring cite of ring closure

Fixed Point Theorems in Quaternion-Valued Metric Spaces

The aim of this paper is twofold. First, we introduce the concept of quaternion metric spaces which generalizes both real and complex metric spaces. Further, we establish some fixed point theorems in quaternion setting. Secondly, we prove a fixed point theorem in normal cone metric spaces for four self-maps satisfying a general contraction condition

Decision Making on Fuzzy Soft Simply* Continuous of Fuzzy Soft Multi-Function

Real world applications are dealing now with a huge amount of data, especially in the area of high dimensional features. In this article, we depict the simply*upper, the simply*lower continuous, we get several characteristics and other properties with respect to upper and lower simply*-continuous soft multifunctions. We also investigate the relationship between soft-continuous, simply*- continuous multifunction. We also implement fuzzy soft multifunction between fuzzy soft topological spaces which is Akdag’s generation of the notion. We are introducing a new class of soft open sets, namely soft simply*open set deduce from soft topology, and we are using it to implement the new approximation space called soft multi-function approach space. Simply*space for approximation based on a simply*open set. The world must adopt modern studies in order to confront epidemics. Accordingly, we presented a new decision proposal in this article, compared our proposed approach to the soft relationship introduced by approximation of Xueyou, and concluded that our approach is better. We also used our proposal in the medical application that was studied in this paper

Bayesian Convolution for Stochastic Epidemic Model

Dengue Hemorrhagic Fever (DHF) is a tropical disease that always attacks densely populated urban communities. Some factors, such as environment, climate and mobility, have contributed to the spread of the disease. The Aedes aegypti mosquito is an agent of dengue virus in humans, and by inhibiting its life cycle it can reduce the spread of the dengue disease. Therefore, it is necessary to involve the dynamics of mosquito's life cycle in a model in order to obtain a reli- able risk map for intervention. The aim of this study is to develop a stochastic convolution susceptible, infective, recovered-susceptible, infective (SIR-SI) mod- el describing the dynamics of the relationship between humans and Aedes aegypti mosquitoes. This model involves temporal trend and uncertainty factors for both local and global heterogeneity. Bayesian approach was applied for the parameter estimation of the model. It has an intrinsic recurrent logic for Bayesian analysis by including prior distributions. We developed a numerical computation and carry out simulations in WinBUGS, an open-source software package to perform Mar- kov chain Monte Carlo (MCMC) method for Bayesian models, for the complex systems of convolution SIR-SI model. We considered the monthly DHF data of the 2016–2018 periods from 10 districts in Kendari-Indonesia for the application as well as the validation of the developed model. The estimated parameters were updated through to Bayesian MCMC. The parameter estimation process reached convergence (or fulfilled the Markov chain properties) after 50000 burn-in and 10000 iterations. The deviance was obtained at 453.7, which is smaller compared to those in previous models. The districts of Wua-Wua and Kadia were consistent as high-risk areas of DHF. These two districts were considered to have a signifi- cant contribution to the fluctuation of DHF cases

Prevalence of Neospora caninum and Toxoplasma gondii Antibodies and DNA in Raw Milk of Various Ruminants in Egypt.

The prevalence of Neospora caninum and Toxoplasma gondii antibodies in raw milk samples was estimated in different ruminants and Egyptian governorates. Of 13 bulk milk samples tested by ELISA, five (38.5%) were positive for antibodies to N. caninum, and two samples were additionally positive for antibodies to T. gondii, resulting in a seroprevalence of 15.4% for both T. gondii and co-infection. In individual milk samples (n = 171) from the same bulks, antibodies to N. caninum were detected in 25.7%, to T. gondii in 14%, and 3.5% had antibodies to both parasites. A strong correlation between the OD values of the bulk samples and of the relevant individual milk samples was found for T. gondii (Pearson r = 0.9759) and moderately strong for N. caninum (Pearson r = 0.5801). Risk factor assessment for individual milk samples revealed that antibodies to T. gondii were significantly influenced by animal species, while no risk factors were detected for N. caninum antibodies. Additionally, DNA of N. caninum was detected in a bulk milk sample of cattle for the first time in Egypt, and DNA of T. gondii was found in bulk milk samples of cattle, sheep and goats. This is the first study in Egypt in which bulk milk samples of different ruminants were tested for the presence of N. caninum and T. gondii antibodies and DNA. Both individual and bulk milk samples are useful tools for monitoring antibody response to N. caninum and T. gondii infections in different ruminants in Egypt