River landscapes and optimal channel networks.

We study tree structures termed optimal channel networks (OCNs) that minimize the total gravitational energy loss in the system, an exact property of steady-state landscape configurations that prove dynamically accessible and strikingly similar to natural forms. Here, we show that every OCN is a so-called natural river tree, in the sense that there exists a height function such that the flow directions are always directed along steepest descent. We also study the natural river trees in an arbitrary graph in terms of forbidden substructures, which we call k-path obstacles, and OCNs on a d-dimensional lattice, improving earlier results by determining the minimum energy up to a constant factor for every [Formula: see text] Results extend our capabilities in environmental statistical mechanics.

Application of liquid-liquid microextraction for the effective separation and simultaneous determination of 11 pharmaceuticals in wastewater samples using high-performance liquid chromatography with tandem mass spectrometry.

A dispersive liquid-liquid microextraction method for the simultaneous determination of 11 pharmaceuticals has been developed. The method is based on a microextraction procedure applied to wastewater samples from different regions of Hungary followed by high-performance liquid chromatography with mass spectrometry. The effect of the nature of the extractant, dispersive solvent, different additives, and extraction time were examined on the extraction efficiently of the dispersive liquid-liquid microextraction method. Under optimal conditions, the linearity for determining the pharmaceuticals was in the range of 1-500 ng/mL, with the correlation coefficients ranging from 0.9922 to 0.9995. The limits of detection and limits of quantification were in the range of 0.31-6.65 and 0.93-22.18 ng/mL, respectively.

Burden of Childhood Cancer and the Social and Economic Challenges in Adulthood: A Systematic Review and Meta-Analysis.

Importance: Significant advancements in pediatric oncology have led to a continuously growing population of survivors. Although extensive research is being conducted on the short-, medium-, and long-term somatic effects, reports on psychosocial reintegration are often conflicting; therefore, there is an urgent need to synthesize the evidence to obtain the clearest understanding and the most comprehensive answer. Objective: To provide a comprehensive review and analysis of the socioeconomic attainment of childhood cancer survivors (CCSs) compared with their unaffected peers. Data Sources: A systematic review and meta-analysis was conducted using data obtained from a comprehensive search of MEDLINE (via PubMed), Embase, and CENTRAL (Cochrane Central Register of Controlled Trials) databases on October 23, 2021; the search was updated until July 31, 2023. Study Selection: Eligible articles reported on educational attainment, employment, family formation, quality of life (QoL), or health-risk behavior-related outcomes of CCSs, and compared them with their unaffected peers. Study selection was performed in duplicate by 4 blinded independent coauthors. Data Extraction and Synthesis: Data extraction was performed in duplicate by 4 independent authors following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Outcome measures were odds ratios (ORs) and mean differences with 95% CIs; data were pooled using a random-effects model. Results: The search identified 43 913 articles, 280 of which were eligible for analysis, reporting data on a total of 389 502 survivors. CCSs were less likely to complete higher levels of education (OR, 0.69; 95% CI, 0.40-1.18), had higher odds of health-related unemployment (OR, 2.94; 95% CI, 1.90-4.57), and showed lower rates of marriage (OR, 0.72; 95% CI, 0.63-0.84) and parenthood (OR, 0.60; 95% CI, 0.49-0.74) compared with population-based controls. Conclusion and Relevance: Study findings suggest that CCSs face several socioeconomic difficulties; as a result, the next goal of pediatric oncology should be to minimize adverse effects, as well as to provide lifelong survivorship support aimed at maximizing social reintegration.

Determination of L-glutathione by spot test and spectrophotometric methods based on its interaction with phenazine.

This research paper presents simple and quick eco-friendly spot test and spectrophotometric methods for the determination of L-glutathione. The spot test assay is based on the formation of a color complex with phenazine methosulphate and L-glutathione on a thin-layer chromatography plate followed by image analysis using a scanner as a detector. For analysis, the image was converted into red, green, and blue (RGB) histograms. A series of parameters that influenced the color formation were investigated, and under the optimal conditions, a good linearity was observed in the range of 200-1000 µg mL-1 and 249-1000 µg mL-1 of L-glutathione with correlation coefficients of 0.9907 for B and 0.9903 for G channels. For the spectrophotometric method, a good linearity was obtained in the range of 2.1-60 µg mL-1 of L-glutathione concentration with a correlation coefficient of 0.9961. A mechanism of the reaction of L-glutathione with phenazine was proposed and confirmed by Fourier transform infrared and mass spectroscopy.

A salting-out assisted liquid-liquid microextraction procedure for determination of cysteine followed by spectrophotometric detection.

A new analytical method for sensitive determination of cysteine based on its interaction with phenazine methosulfate was developed using salting-out liquid-liquid microextraction followed by spectrophotometric detection. The mechanism of the reaction was studied and confirmed by Fourier transform infrared and mass spectroscopy. Experimental parameters affecting the extraction efficiency were investigated and under the optimal conditions, good linearity was observed in the range 0.2 - 6.0 µg mL-1 with a correlation coefficient of 0.9972. The limit of detection and limit of quantification were found to be 0.07 and 0.21 µg mL -1, respectively. The enrichment factor was 25. The developed methodology was applied for analysis of cysteine in food supplements. The obtained data were in good agreement with LC-MS/MS analysis.