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Studies are presented which demonstrate that: (1) irradiation of titanium and zinc oxide pigments produces singlet oxygen; (2) irradiation of titanium dioxide pigments in water yields, hydrogen peroxide; and (3) the formation of singlet oxygen and hydrogen peroxide correlates with chalking tendencies of the pigments. These findings, together with the results of quenching studies, are interpreted in terms of a working hypothesis, for the generation of reactive oxidants, which ties together previous work into a unified scheme. The relative chalking rates of anatase and rutile titanium dioxide as well as the improvement of chalk resistance by surface treatment, are discussed within the framework of this scheme. The role of singlet oxygen in the chalking process, the importance of its presence with regard to the control of chalking, and possible mechanisms for its formation are also discussed.

The study aims to describe the main classes of antioxidants existing in fruit, beverages, vegetables and herbs and the different extraction and application of antioxidants in food. Oxidative degradation of lipids, especially induced by reactive oxygen species, leads to quality deterioration of foods and cosmetics and could have harmful effects on health. A major challenge is to develop tools to assess the antioxidant capacity and real efficacy of these molecules. Recently, many review papers regarding antioxidants from different sources and different extraction and quantification procedures have been published. However, none of them has all the information regarding antioxidants (sources, extraction and application in food).

This paper tries to take a different perspective on antioxidants for the new researcher involved in this field.

Antioxidants from fruit, vegetables and beverages play an important role in human health, for example, preventing cancer and cardiovascular diseases and lowering the incidence of different diseases. A number of plant products act as scavengers of free radical species and so have been classified as antioxidants. Antioxidants are an important group of food additives that have the ability to protect against detrimental change of oxidizable nutrients and consequently they extend shelf-life of foods.

Most of the antioxidants present in foods are phenolic and polyphenolic compounds, but their efficacy in food for the prevention of oxidation or in the body for dealing with oxidative stress and its consequences depends on different factors.

This study collected the last finding in the field of sources and applications of natural antioxidants.

The purpose of this paper is to improve the generation efficiency of singlet oxygen of methylene blue molecules through finely controlling their aggregation states in drug carriers.

As a photosensitiser in photodynamic therapy, methylene blue (MB) was loaded on citrate-modified hydroxyapatite (HAp) through an electrostatic interaction and followed by encapsulation of coordination complexes of tannic acid (TA) and Fe(III) ions. Ultraviolet-visible absorption spectrum of the supernatant after incubation of samples was recorded at certain time interval to investigate the release behaviour of MB. Photodynamic activity of MB was determined by the oxidation reaction of uric acid by singlet oxygen generated by MB under illumination.

Almost all MB molecules were immediately released from HAp-MB, whilst an initial burst release of MB from HAp-MB@TA was followed by a sustainable and pH-sensitised release. In comparison with HAp-MB, photocatalystic reduction of HAp-MB@TA by titanium dioxide hardly occurred under illumination, indicating the stability against reduction to leukomethylene blue in vitro. Generation efficiency of singlet oxygen by MB released from HAp-MB@TA was significantly higher than that from HAp-MB because of the control of TA and Fe(III) ions complexes on molecular structures of released MB.

A facile method was herein demonstrated to optimise the generation efficiency of singlet oxygen by controlling aggregation states of PS molecules and improve PDT efficiency to damage tumour tissues.

A control of the first‐line human defence system, using mechanisms analogous to specific and non‐specific (parametric) triggering of phagocytosis, is proposed on the basis of an autocatalytic model of biphasic modulation of phagocyte luminescence by experimental peptide medicines. Properties of the autocatalytic model are described and its catastrophe and bifurcation sets determined. The mechanism analogous to parametric triggering is shown to result from a fold catastrophe produced by the changes in the autocatalytic interaction parameter characterising a given peptide preparation. Usefulness of the model was shown by its application to two distinct peptide preparations having different immunomodulatory properties.

This study aims to analyze the levels of vitamin C, phenolic compounds and antioxidants in baby food. Providing nutritious food to the infants is essential for their growth and development. Baby foods are foods prepared from any suitable nutritive material and intended for feeding children after six months of age. The search for foods that meet the nutritional needs of children and that also promote aspects of health has increased on the part of parents.

A total of 17 different types of baby foods (2 brands) were purchased and the vitamin C content, total phenolic compounds (TPC) and antioxidant activity were determined. The authors also assessed the adequacy of labeling in accordance with regulatory parameters. Data was submitted to analysis of variance, and the means were compared by the Tukey test at 5% probability. Principal component analysis was performed to evaluate the results (phenolic compounds, vitamin C and antioxidant activity) from the multidimensional point of view.

In general, the labeling of baby foods proved to be within the legislation, but with confusing information for the consumer. BF7-AAPO (apple pulp and juice, papaya and orange juice), BF-BAO (banana, apple juice and oatmeal) and BF-AA (apple pulp and juice) showed the highest vitamin C content (20–28 mg/100 g; p < 0.001). BF-A (apple), BF-B (banana) and BF-AA showed the highest TPC (7–8.2 mg/100 g; p < 0.001). BF-CP (cassava-parsley), BF-PCBCP (potato, carrot, beef and cassava-parsley) and BF-PCBB (potato, carrot, beef and broccoli) showed the highest antioxidant activity (44–48%; p < 0.001). High value of TPC was related to high value of antioxidant activity in baby foods. In conclusion, vitamin C content in the baby foods was different from those reported on the labels and there was a direct relationship between the content of TPC and the antioxidant capability.

The objective of this work was to evaluate bioactive compounds and antioxidant activity in baby foods. So far, few papers have reported on the subject as the authors seek to know about essential nutrients. However, this knowledge is important because these compounds can decrease and/or prevent inflammatory processes in the body.

Three-dimensional (3D) printing is popular for many applications including the production of photocatalysts. This paper aims to focus on developing of 3D-printed photocatalyst-nano composite lattice structure. Digital light processing (DLP) 3D printing of photocatalyst composites was performed using photosensitive resin mixed with 0.5% Wt. of TiO₂ powder and varying amounts (0.025% Wt. to 0.2% Wt.) of graphene nanoplatelet powder. The photocatalytic efficiency of DLP 3D-printed photocatalyst TiO₂ composite was investigated, and the effects of nano graphite powder incorporation on the photocatalytic activity, thermal and mechanical properties were investigated.

Methods involve 3D computer-aided design modeling, printing parameters and comprehensive characterization techniques such as structural equation modeling, X-ray diffraction, thermogravimetric analysis, Fourier-transform infrared (FTIR) and mechanical testing.

Results highlight successful dispersion and characteristics of TiO₂ and graphene nanoplatelet (GNP) powders, intricate designs of 3D-printed lattice structures, and the influence of GNPs on thermal behavior and mechanical properties.

The study suggests applicability in wastewater treatment and environmental remediation, showcasing the adaptability of 3 D printing in designing effective photocatalysts. Future research should focus on practical applications and the long-term durability of these 3D-printed composites.

Clinical outcome in patients with ischemic heart disease can be significantly improved with the implementation of targeted drug delivery into the ischemic myocardium. The purpose of this paper is to review the data of recent literature and present original findings relevant to the problem of therapeutic heart targeting with use of nanoparticles.

For literature review, a public‐domain database (Medline) was searched using a web‐based search engine (PubMed) and the following key words: “nanoparticles”, “nanocarriers”, and “targeted drug delivery”. Experimental approaches included fabrication of carbon and silica nanoparticles, their characterization and surface modification. The acute hemodynamic effects of nanoparticle formulation as well as nanoparticle biodistribution were studied on male Wistar rats.

Carbon and silica nanoparticles are biocompatible materials that can be used as carriers for heart‐targeted drug delivery. Concepts of passive and active targeting can be applied to the development of targeted drug delivery to the ischemic myocardial cells.

The present paper is believed to be the first on ligand‐directed targeted drug delivery into the damaged myocardium.

The latest international research on vitamin C and its possible role in reducing the risk of cancers, heart disease and other serious ailments was presented at a conference held recently in Glasgow. The conference was held to celebrate ten years of production of vitamin C by Roche Products at Dairy. Professor Ronald Anderson from the University of Pretoria reviewed the origins and adverse effects on health of oxygen‐free radicals, and other reactive oxidants generated during activation of the human immune system, and the protective role of the anti‐oxidant nutrient vitamin C in the prevention of free radical‐mediated immune dysfunction, tissue damage and carcinogenesis during inflammatory responses. Here we include extracts from his paper.

UV curing technology has a number of unique advantages over the conventional curing technologies. However, until very recently, there had been few successful examples of the application of UV curing technology in ink‐jet printing. Several reasons, including the requirement of low viscosity for ink‐jet printing inks, were responsible for the lack of development of UV curable ink‐jet printing inks. This paper describes, in some details, the challenges that a formulator had to face in developing UV curable ink‐jet printing inks, together with information on the status quo of UV curable ink‐jet printing technology.