Human Milk-The Biofluid That Nourishes Infants from the First Day of Life.

Human milk is a biofluid with a unique composition among mammalian milks. Besides this milk's major components, its bioactive compounds, like hormones, immune factors, and oligosaccharides, are unique and important for infant growth and development. The best form of nutrition for term and preterm infants is the mother's own milk. However, in the absence of the mother's own milk, donor milk should be made available. Milk banks support neonatal intensive care units by providing preterm infants with human milk that generally has reasonable nutritive value for this sensitive population. However, neither mother's own milk nor donor milk has sufficient energy content for the growth of preterm babies, so adequate human milk supplementation is crucial for their progress. Due to the different characteristics of human breast milk, as well as ubiquitous environmental pollutants, such as microplastics, new methods are required for monitoring the quality and characteristics of human milk, which will lay a solid foundation for the further development and progress of human milk research.

Prediction of the Impact of Land Use and Soil Type on Concentrations of Heavy Metals and Phthalates in Soil Based on Model Simulation.

The main objective of this study is to determine the possibility of predicting the impact of land use and soil type on concentrations of heavy metals (HMs) and phthalates (PAEs) in soil based on an artificial neural network model (ANN). Qualitative analysis of HMs was performed with inductively coupled plasma-optical emission spectrometry (ICP/OES) and Direct Mercury Analyzer. Determination of PAEs was performed with gas chromatography (GC) coupled with a single quadrupole mass spectrometry (MS). An ANN, based on the Broyden-Fletcher-Goldfarb-Shanno (BFGS) iterative algorithm, for the prediction of HM and PAE concentrations, based on land use and soil type parameters, showed good prediction capabilities (the coefficient of determination (r2) values during the training cycle for HM concentration variables were 0.895, 0.927, 0.885, 0.813, 0.883, 0.917, 0.931, and 0.883, respectively, and for PAEs, the concentration variables were 0.950, 0.974, 0.958, 0.974, and 0.943, respectively). The results of this study indicate that HM and PAE concentrations, based on land use and soil type, can be predicted using ANN.

Green Infrastructure Designed through Nature-Based Solutions for Sustainable Urban Development.

With the goal of enhancing the quality of the environment, urban green infrastructure (UGI) is an essential element in sustainable cities, and nature-based solutions (NBS) are being carried out as new infrastructure solutions that increase the resilience of cities. In this research, the method of theoretical analysis and the content analysis as the basic fact-gathering technique was applied to answer to following questions: What are the hindrances and bottlenecks in implementing NBS? Are the current decision-making mechanisms helping NBS get in route to shape cities? Is there any binding policy in practice that promotes NBS? In Belgrade is planned Type 3 of the degree of intervention/level and engineering type-Creation and new ecosystem management in the classifications of intensive urban green space management; urban planning strategies; urban water management; ecological restoration of degraded terrestrial ecosystems; and restoration and creation of semi-natural water bodies and hydrographic networks. In the future, it is essential to implement policies and incentives on national, regional, and local scales that help encourage the usage of NBS in the development of urban infrastructure.

Overcoming the asymmetry of the electron and hole doping for magnetic transitions in bilayer CrI3.

Electrical control of magnetism has great potential for low-power spintronics applications and the newly discovered two-dimensional van der Waals magnetic materials are promising systems for this type of applications. In fact, it has been recently shown experimentally (Jiang et al., Nat. Nanotechnol., 2018, 13, 549-553) that upon electrostatic doping by electrons bilayer CrI3 undergoes an antiferromagnetic-ferromagnetic (AFM-FM) phase transition, even in the absence of magnetic field. Doping by holes, on the other hand, does not induce the same transition in the experiment, which points to an intrinsic asymmetry in the hole and electron doping that limits the control of the transition by doping. We here show, based on first-principles calculations, that the asymmetry originates in the relativistic nature of the valence-band-edge states of the pristine bilayer, which inhibits the magnetic transition upon hole doping. Based on this finding, we propose an approach to overcome the asymmetry and predict the existence of the AFM-FM transition for both hole and electron doping upon moderate uniaxial compression along the soft direction of the bilayer.

Is Kragujevac city still a "hot spot" area, twenty years after the bombing?

After NATO bombing of Serbia in 1999, UNEP has identified Kragujevac as one of the four heavily polluted environmental "hot spots". Damaging of industrial and military targets caused the release of substantial amounts of hazardous chemical substances into the environment. This study was conducted in order to access the exposure of residents of Kragujevac city to persistent soil pollutants, twenty years after NATO air campaign. The paper reports the results of measuring radionuclides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and heavy metals (As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Zn, and Hg) in soil samples collected from two depths (0-15 cm and 15-30 cm) at 30 locations along the riverbank of the Lepenica River. The average specific activities of 226Ra, 232Th, 40K and 137Cs were comparable to average worldwide values; excess lifetime cancer risk (ELCR) from natural radionuclides ranged from 1.1·10-4 to 3.3·10-4. The measured concentrations of As, Co, Cr, Cu, and Ni exceeded the limit values in most of the samples. Non-carcinogenic risk (hazard quotient and hazard index) and carcinogenic risk from heavy metals were assessed. Total hazard index was 0.257 and 2.16 for adults and children, respectively. Sum of measured PAHs ranged from 110 to 1026 µg kg-1. Sum of PCBs exceeded the limit value of 20 µg kg-1 in all samples (it ranged from 48.8 to 196.8 µg kg-1), but it was still below the remediation level. The differences between two layers with respect to all measured variables were not statistically significant.

Evaluation of heavy metals and radionuclides in fish and seafood products.

Despite the existence of a legislation regarding food contaminants, food safety control in Serbia is a matter of great concern. This study investigates the radioactivity levels and heavy metal concentrations in fish and seafood commercially available in Serbian markets. Domestic fish species (caught in the Danube River) and fishery products imported from Europe, Asia and America were analyzed. The content of natural radionuclides and 137Cs were investigated by gamma spectrometry. Activity concentration of 40 K was measured in the range of 44-165 Bq kg-1; low levels of 137Cs were detected in two samples (2.8 and 3.0 Bq kg-1), while concentrations of 226Ra and 232Th were below minimal detectable values. Concentrations of heavy metals (Cd, Hg and Pb) were determined using ICP-OES method. Cd concentration ranged from 0.01 to 0.81 mg kg-1 in sea fish and from 0.01 to 0.03 mg kg-1 in freshwater fish. Hg concentrations were in the range of 0.01-1.47 mg kg-1; the highest value was measured in the predator fish - shark. The highest level of Pb (6.56 mg kg-1) was detected in a blue sea fish (Atlantic mackerel). The health risks associated with the intake of heavy metals and radionuclides via fish consumption were evaluated. The results indicate that fish and seafood consumption do not pose a significant health concern in the case of the usual consumption rate which is typical for the population of Serbia. However, a highly frequent consumption of fishery products can have adverse health effects, especially due to Hg and Pb contamination.

Strong chemisorption of CO2 on B10-B13 planar-type clusters.

An ab initio density functional study was performed investigating the adsorption of CO2 on neutral boron B n (n = 10-13) clusters that are characterized by planar and quasiplanar ground-state atomic structures. For all four clusters, we found large chemisorption binding energies, reaching 1.6 eV between CO2 and B12, with the adsorbed molecule oriented in the plane of the cluster and adsorbed along the cluster edge. A configuration with chemisorbed dissociated CO2 molecule also exists for B11 and B13 clusters. The strong adsorption is due to the bending of the CO2 molecule, which provides energetically accessible fully in-plane frontier molecular orbitals matching the edge states of the clusters. At the same time, the intrinsic dipole moment of a bent CO2 molecule facilitates the transfer of excess electronic charge from the cluster edges to the molecule.

Nanobubbles at GPa Pressure under Graphene.

We provide direct evidence that irradiation of a graphene membrane on Ir with low-energy Ar ions induces formation of solid noble-gas nanobubbles. Their size can be controlled by thermal treatment, reaching tens of nanometers laterally and height of 1.5 nm upon annealing at 1080 °C. Ab initio calculations show that Ar nanobubbles are subject to pressures reaching tens of GPa, their formation being driven by minimization of the energy cost of film distortion and loss of adhesion.

Temperature-driven reversible rippling and bonding of a graphene superlattice.

In order to unravel the complex interplay between substrate interactions and film configuration, we investigate and characterize graphene on a support with non-three-fold symmetry, the square Ir(100). Below 500 °C, distinct physisorbed and chemisorbed graphene phases coexist on the surface, respectively characterized by flat and buckled morphology. They organize into alternating domains that extend on mesoscopic lengths, relieving the strain due to the different thermal expansion of film and substrate. The chemisorbed phase exhibits exceptionally large one-dimensional ripples with regular nanometer periodicity and can be reversibly transformed into physisorbed graphene in a temperature-controlled process that involves surprisingly few C-Ir bonds. The formation and rupture of these bonds, rather than ripples or strain, are found to profoundly alter the local electronic structure, changing graphene behavior from semimetal to metallic type. The exploitation of such subtle interfacial changes opens new possibilities for tuning the properties of this unique material.

Prediction of toxicity and data exploratory analysis of estrogen-active endocrine disruptors using counter-propagation artificial neural networks.

In this work, a novel algorithm for optimization of counter-propagation artificial neural networks has been used for development of quantitative structure-activity relationships model for prediction of the estrogenic activity of endocrine-disrupting chemicals. The search for the best model was performed using genetic algorithms. Genetic algorithms were used not only for selection of the most suitable descriptors for modeling, but also for automatic adjustment of their relative importance. Using our recently developed algorithm for automatic adjustment of the relative importance of the input variables, we have developed simple models with very good generalization performances using only few interpretable descriptors. One of the developed models is in details discussed in this article. The simplicity of the chosen descriptors and their relative importance for this model helped us in performing a detailed data exploratory analysis which gave us an insight in the structural features required for the activity of the estrogenic endocrine-disrupting chemicals.