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Objectives Human milk (HM) is a complex fluid that meets the nutritional needs of infants. Its composition idrfs associated with environmental, maternal, and foetal variables. It provides nutrients and bioactive substances, including cytokines, immunoglobulins, and constituents with antioxidative properties. Boys are reportedly more susceptible to oxidative stress. This study aimed to determine the relationship between infant sex and the antioxidants vitamins C and E, and the fatty acid (FA) profile of HM. Results of this investigation may infer sex differences for the composition of infant formulas. Methods Thirty days after delivery, a sample of HM was collected from 152 healthy, non-smoking mothers of full-term new-borns (77 males) born in good clinical condition. After FAs were extracted from the fat component, they were converted into methyl esters and separated using high-performance gas chromatography. Tocopherol content was determined using a method described in a previous study. Vitamin C content was determined using reversed-phase high-performance liquid chromatography with ultraviolet detection, as described in the same study. Results The study groups (male versus female offspring) did not differ in terms of vitamin and FA content in HM. The only difference found was in gondoic acid 20:1 (n-9), with a higher concentration in the HM of mothers with female offspring (mean 0.63 ± 0.18 versus 0.59 ± 0.15 g/100 g FA; p Conclusions Despite the acknowledged differences in the composition of HM associated with infant sex and the increased oxidative stress in males, antioxidant content did not appear to differ according to infant sex. These results suggest that there is no need for the antioxidant content of infant formulas to be sex specific.

Increased investment in perinatal health in developing countries has improved the survival of preterm newborns, but their significant multiorgan immaturity is associated with short and long-term adverse consequences. Cathepsin B, as a protease with angiogenic properties, may be related to the process of nephrogenesis. A total of 88 neonates (60 premature children, 28 healthy term children) were included in this prospective study. We collected urine samples on the first or second day of life. In order to determine the concentration of cathepsin B in the urine, the commercially available enzyme immunoassay was used. The urinary concentrations of cathepsin B normalized with the urinary concentrations of creatinine (cathepsin B/Cr.) in newborns born at 30–34, 35–36, and 37–41 (the control group) weeks of pregnancy were (median, Q1–Q3) 4.00 (2.82–5.12), 3.07 (1.95–3.90), and 2.51 (2.00–3.48) ng/mg Cr, respectively. Statistically significant differences were found between the group of newborns born at 30–34 weeks of pregnancy and the control group (p &lt, 0.01), and between early and late preterm babies (PTB) (p &lt, 0.05). The group of children born at 35–36 weeks of pregnancy and the control group did not differ significantly. This result suggests that the elevated urinary cathepsin B/Cr. level may be the result of the kidneys’ immaturity in preterm newborns.

New, monometallic nanoparticles (MNPs) decorated surface and rare earth (RE) ions doped lattice of perovskite-type (KTaO 3 )/pyrochlore-type (K 2 Ta 2 O 6 ) photocatalysts were successfully prepared by facile hydrothermal incorporation of RE ions into KTaO 3 /K 2 Ta 2 O 6 lattices followed by photodeposition of MNPs. The impact of noble metal type (MNPs = Au, Pt, Rh) and rare earth dopant type (RE = Er, Pr) on the physicochemical properties correlated with photoactivity of MNPs/RE-KTaO 3 and MNPs/RE-K 2 Ta 2 O 6 has been examined. All as-prepared photocatalysts were systematically characterized by UV–vis diffuse reflectance spectroscopy, photoluminescence emission spectroscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, fast Fourier transform, powder X-ray diffraction, and X-ray photoelectron spectroscopy. The crystal structure was presented using VESTA software. Photocatalytic activity of samples under visible light irradiation was determined by pollutant decomposition, while UV–vis induced activity was estimated by H 2 generation efficiency. The experimental results suggested a synergistic effect between MNPs and RE-ions-modified KTaO 3 /K 2 Ta 2 O 6 , which resulted in greatly improved photocatalytic performance compared with that of pristine KTaO 3 /K 2 Ta 2 O 6 . Inclusion of RE ions into KTaO 3 /K 2 Ta 2 O 6 lattices probably leads to formation of RE4 f states below the conduction band levels to electron transition by lower photon excitation energy, while photoreduction of MNPs on the RE-KTaO 3 /RE-K 2 Ta 2 O 6 surface causes localized surface plasmon resonance and activates surface by adsorption for both O 2 and H 2 O molecules. The highest visible-light-induced photoactivity was observed for the Au/Er-KTaO 3 sample (16.48%) in phenol solution degradation and for the Pt/Pr-K 2 Ta 2 O 6 photocatalyst (36.13%) in gaseous toluene removal, respectively. Active species-trapping tests indicate that O 2 − radicals are meaningfully involved in phenol oxidation under visible light irradiation. The largest amount of H 2 evaluation was observed for the Pt/Pr-K 2 Ta 2 O 6 sample (93.16 µmol/min) under UV–vis irradiation, which also showed a relatively good lifetime in recycling. The present study describes noble- and rare-earth-metal-modified KTaO 3 /K 2 Ta 2 O 6 as an advanced material in photocatalysis.

In the present work, two H2 evolution photocatalysts were prepared by employing two different oxides, TiO2 and zirconium titanate (ZrTiO4), as the support of various copper phases. For both the supports the same Cu loading (0.5% w/w) was adopted, but two different impregnation procedures have been followed, leading to different forms of Cu in the final composite material that are: (i) Cu(II) species dispersed on the oxide surface and (ii) Cu2O particles dispersed on the oxide surface. The present paper based on the parallel use of photocatalytic test and spectroscopic analysis performed in catalytic conditions illustrates the evolution of photocatalytic systems occurring during the H2 evolution reaction tests, pointing out that the as-prepared materials represent a pre-catalyst and they are modified during irradiation leading to the real working systems different from the starting ones. The herein presented spectroscopic analysis aims to contribute to the living debate on the oxidation state of copper in mixed Cu/oxide materials and on its role in hydrogen evolution under photocatalytic conditions.

Novel mono- and bimetallic nanoparticles (MNPs and BNPs) decorated surface of perovskite-type KTaO3 photocatalysts were successfully synthesized by hydrothermal reaction of KTaO3 followed by photodeposition of MNPs/BNPs. The effect of noble metal type (MNPs = Au, Ag, Pt, Pd, Rh, Ru or BNPs = Au/Pt, Ag/Pd, Rh/Ru), amount of metal precursor (0.5, 1.0, 1.5 or 2.0 wt%) as well as photoreduction method (simultaneous (both) or subsequent (seq) deposition of two metals) on the physicochemical and photocatalytic properties of MNPs- and BNPs-KTaO3 have been investigated. All as-prepared photocatalysts were subsequently characterized by UV–Vis diffuse reflectance spectroscopy (DRS), Brunauer-Emmett-Teller (BET) specific surface area and pore size distribution measurement, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), powder X-ray diffraction (PXRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and photoluminescence (PL) emission spectroscopy. The crystal structure was performed using visualization for electronic and structural analysis (VESTA). The photocatalytic activity under Vis light irradiation was estimated in phenol degradation in aqueous phase and toluene removal in gas phase, while under UV–Vis light irradiation was measured amount of H2 generation from formic acid solution. The absorption properties of O2 and H2O molecules on KTaO3(1 0 0) surface supported by Au or Au/Pt NPs was also investigated using density-functional theory (DFT). The experimental results show that, both MNPs-KTaO3 and BNPs-KTaO3 exhibit greatly enhanced pollutant decomposition efficiency under Vis light irradiation and highly improved H2 production under UV–Vis light irradiation compared with pristine KTaO3. MNPs deposition on KTaO3 surface effects by disperse metal particle size ranging from 11 nm (Ru NPs) to 112 nm (Au NPs). Simultaneous addition of Au/Pt precursors results in formation of agglomerated larger metal nanoparticles (50–100 nm) on KTaO3 surface than subsequent deposition of Au/Pt with composition of concentrated smaller metal nanoparticles (>50 nm) on KTaO3 surface. The 0.5 Au/1.5 Pt-KTaO3_both and 2.0 Rh-KTaO3 reveal the highest Vis-induced activity among prepared samples in aqueous phase (14.75% of phenol decomposition after 90 min of irradiation) and gas phase (41.98% of toluene removal after 60 min of irradiation), respectively. The theoretical calculations confirmed that adsorption energy of O2 and H2O molecules was increased after loading of Au or Au/Pt NPs on KTaO3(1 0 0) surface. Control tests with scavengers show that O2 − radical is significantly involved in phenol oxidation under Vis light irradiation, which proposed mechanism is based on direct electron transfer from MNPs/BNPs to conduction band of KTaO3. The highest amount of H2 evaluation is obtained also by 0.5 Au/1.5 Pt-KTaO3_both after 240 min of UV–Vis light irradiation (76.53 µmol/min), which is eleven times higher than for pristine KTaO3 (6.69 µmol/min). Moreover, the most photocatalytic samples for each model reaction present good repeatability and stability after subsequent three cycles. Summarized, MNPs- and BNPs-KTaO3 are promising material in advanced applications of photocatalysis.

Novel rare earth-doped K2Ta2O6 (RE-K2Ta2O6) photocatalysts were successfully synthesized by one-step hydrothermal method. The effect of dopant type (RE = Y, Yb, Ho, Pr, Er) and amount of rare earth precursor (2, 4, 8 and 10 mol%) on the physicochemical and photocatalytic properties of RE-K2Ta2O6 have been investigated. All as-prepared materials were subsequently characterized by UV–vis diffuse reflectance spectroscopy (DRS), Brunauer-Emmett-Teller (BET) specific surface area measurement, scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS), powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, mass magnetic susceptometry and photoluminescence (PL) emission spectroscopy. The photocatalytic activity under UV–vis light irradiation was estimated in phenol degradation in aqueous phase, toluene removal in gas phase and H2 generation from formic acid solution. The experimental results show that, novel RE-K2Ta2O6 exhibits greatly improved degradation efficiency under UV–vis light irradiation compared with pristine K2Ta2O6. The Er-K2Ta2O6 and Pr-K2Ta2O6, obtained by introducing of 2 mol% of RE ions during synthesis, reveal the highest photocatalytic activity among prepared samples in aqueous phase (33% of phenol decomposition after 90 min of irradiation) and gas phase (45% of toluene removal after 60 min of irradiation), respectively. Moreover, both photocatalysts present good stability after subsequent three cycles. The active species trapping test shows that OH and O2 − radicals are significantly involved in phenol oxidation under UV–vis light irradiation. The amount of H2 evolution increases with increasing addition of Er dopant into K2Ta2O6 lattice. The highest H2 production is obtained for 10 mol% Er-K2Ta2O6 after 240 min of UV–vis light irradiation (15.40 μmol/min). Enhanced photoactivity performance can be attributed to incorporation of RE ions at K+ lattice site in RE-K2Ta2O6, probably leading to formation of new RE 4f states below the conduction band of K2Ta2O6 structure. To investigate the localization of RE ions in K2Ta2O6 structure, the band structure and partial density of the states (PDOS) have been investigated. Computer simulations were performed using plane-wave based Vienna ab-initio simulation package (VASP) with the generalized gradient approximation (GGA) by Perdew-Burke-Ernzerhof (PBE). Moreover, inclusion of RE ions in K2Ta2O6 causes predominance pyrochlore phase formation over perovskite in regular cubic structure. Summarized, RE-doped K2Ta2O6 is promising material in photocatalytic degradation of organic pollutants and H2 generation processes. Our work may provide valuable information for rare earth doping semiconductor with improved photocatalytic performance.

In the present work, two H

Ionic liquids (ILs) are widely applied to prepare metal nanoparticles and 3D semiconductor microparticles. Generally, they serve as a structuring agent or reaction medium (solvent), however it was also demonstrated that ILs can play a role of a co-solvent, metal precursor, reducing as well as surface modifying agent. The crucial role and possible types of interactions between ILs and growing particles have been presented in the Part 1 of this review paper. Part 2 of the paper gives a comprehensive overview of recent experimental studies dealing with application of ionic liquids for preparation of metal and semiconductor based nano- and microparticles. A wide spectrum of preparation routes using ionic liquids is presented, including precipitation, sol-gel technique, hydrothermal method, nanocasting and ray-mediated methods (microwave, ultrasound, UV-radiation and γ-radiation). It was found that ionic liquids formed of a 1-butyl-3-methylimidazolium [BMIM] combined with tetrafluoroborate [BF4], hexafluorophosphate [PF6], and bis(trifluoromethanesulfonyl)imide [Tf2N] are the most often used ILs in the synthesis of nano- and microparticles, due to their low melting temperature, low viscosity and good transportation properties. Nevertheless, examples of other IL classes with intrinsic nanoparticles stabilizing abilities such as phosphonium and ammonium derivatives are also presented. Experimental data revealed that structure of ILs (both anion and cation type) affects the size and shape of formed metal particles, and in some cases may even determine possibility of particles formation. The nature of the metal precursor determines its affinity to polar or nonpolar domains of ionic liquid, and therefore, the size of the nanoparticles depends on the size of these regions. Ability of ionic liquids to form varied extended interactions with particle precursor as well as other compounds presented in the reaction media (water, organic solvents etc.) provides nano- and microstructures with different morphologies (0D nanoparticles, 1D nanowires, rods, 2D layers, sheets, and 3D features of molecules). ILs interact efficiently with microwave irradiation, thus even small amount of IL can be employed to increase the dielectric constant of nonpolar solvents used in the synthesis. Thus, combining the advantages of ionic liquids and ray-mediated methods resulted in the development of new ionic liquid-assisted synthesis routes. One of the recently proposed approaches of semiconductor particles preparation is based on the adsorption of semiconductor precursor molecules at the surface of micelles built of ionic liquid molecules playing a role of a soft template for growing microparticles.

Ionic liquids (ILs) are a broad group of organic salts of varying structure and properties, used in energy conversion and storage, chemical analysis, separation processes, as well as in the preparation of particles in nano- and microscale. In material engineering, ionic liquids are applied to synthesize mainly metal nanoparticles and 3D semiconductor microparticles. They could generally serve as a structuring agent or as a reaction medium (solvent). This review deals with the resent progress in general understanding of the ILs role in particle growth and stabilization and the application of ionic liquids for nano- and microparticles synthesis. The first part of the paper is focused on the interactions between ionic liquids and growing particles. The stabilization of growing particles by steric hindrance, electrostatic interaction, solvation forces, viscous stabilization, and ability of ILs to serve as a soft template is detailed discussed. For the first time, the miscellaneous role of the ILs in nano- and microparticle preparation composed of metals as well as semiconductors is collected, and the formation mechanisms are graphically presented and discussed based on their structure and selected properties. The second part of the paper gives a comprehensive overview of recent experimental studies dealing with the applications of ionic liquids for preparation of metal and semiconductor-based nano- and microparticles. A wide spectrum of preparation routes using ionic liquids are presented, including precipitation, sol-gel technique, hydrothermal method, nanocasting, and microwave or ultrasound-mediated methods.

A mouse spermatozoon was injected into mouse secondary oocytes (ICSI) in the vicinity of the metaphase spindle. In 22% of oocytes injected successfully, the maternal chromatin (the haploid chromatids formed after the second meiotic division) and paternal chromatin (from the sperm nucleus) were surrounded by a common nuclear envelope to form one diploid bi-parental pronucleus. However, the use of spermatozoa in which BrdU had been incorporated into DNA during spermatogenesis revealed, that maternal and paternal chromatin occupied two separate compartments within the one pronucleus. In the living state, the diploid pronucleus could be distinguished from a haploid one by its distinctly larger size and by a greater number of “nucleolus-like bodies”—criteria confirmed karylogically at the 1st cleavage division. Such zygotes with one diploid pronucleus were able to develop in vitro into blastocysts as often as those with two haploid pronuclei [11/29 (38%) vs. 14/35 (40%)]. Seventy nine 2-cell embryos developing in vitro from zygotes with one diploid pronucleus were transplanted to the oviducts of pseudopregnant recipients: two females had six foetuses when killed on the 17th day, and two females gave birth to nine young, eight of which survived and developed into normal fertile animals. Mol. Reprod. Dev. © 2005 Wiley-Liss, Inc.