Publications by authors named "Leszczynski J"

Article Synopsis
  • Boron-dipyrromethene (BODIPY) compounds have valuable optical properties and are used in various fields like imaging and electronics; to enhance their design, understanding the link between their structures and optical properties is essential.
  • A machine learning-based model was developed, showing high predictive accuracy for the BODIPY compounds' maximum absorption wavelength, proving its effectiveness through strong correlation coefficients.
  • The study used computational chemistry methods to optimize BODIPY structures and employed machine learning techniques to analyze 131 compounds, highlighting the significance of molecular characteristics like branching and specific functional groups in determining their properties.
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The aim of this work was to investigate the possibility of doping copper sulfide CuS with selected fifth-group elements, potentially having a positive effect on the thermoelectric properties of the resulting materials. For the selected model structures, theoretical calculations and an analysis of the electronic structure and changes in the enthalpy of formation due to doping were performed using the WIEN2k package employing the Full-Potential Linearized Augmented Plane Wave (FP-LAPW) method within density functional theory (DFT) formalism. Polycrystalline materials with the nominal composition of CuSX ( = P, As, Sb, Bi) were synthesized in quartz ampoules, then sintered using the spark plasma sintering (SPS) technique and "SPS melting" method.

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Even though COVID-19 is no longer the primary focus of the global scientific community, its high mutation rate (nearly 30 substitutions per year) poses a threat of a potential comeback. Effective vaccines have been developed and administered to the population, ending the pandemic. Nonetheless, reinfection by newly emerging subvariants, particularly the latest JN.

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Large-scale implementation of NTO (5-nitro-1,2,4-triazol-3-one), an energetic material used in military applications, causes its discharge to the environment. Reduction of NTO with bacterial nitroreductase or iron-containing minerals results in the formation of ATO (5-amino-1,2,4-triazol-3-one), which is an important intermediate in the process of NTO degradation in the environment. ATO may be dissolved in surface water and groundwater due to its good water solubility.

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The endovenous embolization of insufficient abdominal/pelvic veins is the preferred method of treatment. Also, it seems to be crucial in the treatment of lower limb vein insufficiency, particularly in recurrent disease. This study aimed to evaluate of pelvic vein embolization safety and its impact on the short-term outcome in the sequential treatment of venous disease.

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A common concern in preclinical cancer research is the introduction of Corynebacterium bovis into immunodeficient mouse colonies through cancer cell lines. C. bovis is a known contaminant of patient-derived xenograft tumors passaged horizontally between immunodeficient mice.

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Article Synopsis
  • Sunlight creates reactive oxygen species that help break down environmental pollutants, including a chemical called ATO, which is derived from the munition ingredient NTO.
  • A study was conducted to explore how ATO decomposes in water, focusing on different reactive agents like superoxide, hydroperoxyl radical, and singlet oxygen, through advanced computational methods.
  • The findings indicate that while superoxide is less effective, hydroperoxyl radical and singlet oxygen can effectively decompose ATO in a multi-step process, ultimately leading to the formation of simpler inorganic compounds.
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infection in biomedical research is synonymous with skin hyperkeratosis of athymic nude mice. This clinical sign can be obvious and is the namesake for 'scaly skin disease.' Other clinical signs that accompany scaly skin, including early presentation, duration, and rate of resolution, are less well known.

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Clean and renewable energy development is becoming frontier research for future energy resources, as renewable energy offers sustainable and environmentally friendly alternatives to non-renewable sources such as fossil fuels. Among various renewable energy sources, tremendous progress has been made in converting solar energy to electric energy by developing efficient organic photovoltaics. Organic photovoltaic materials comprising conjugated polymers (CP) with narrow optical energy gaps are promising candidates for developing sustainable sources due to their potentially lower manufacturing costs.

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Article Synopsis
  • - The study compares fine-needle aspiration cytology (FNAC) results with postoperative histopathology to diagnose thyroid abnormalities, acknowledging FNAC's limitations despite being the gold standard.
  • - Involving 344 patients with a notable female majority, the results showed FNAC's sensitivity at 92.31% and specificity at 82.08%, with a significant number (25%) being misdiagnosed.
  • - While FNAC can lead to diagnostic errors that may affect treatment decisions, it still remains the best preliminary diagnostic tool available for thyroid issues.
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The thermolysis of -3,4-dimethyl-1,2-dioxetane is studied by trajectory surface hopping. The significant difference between long and short dissociation times is rationalized by frustrated dissociations and the time spent in triplet states. If the C-C bond breaks through an excited state channel, then the trajectory passes over a ridge of the potential energy surface of that state.

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Depending on the strain of immunodeficient mice, infection can be asymptomatic or cause transient or prolonged skin disease. infection of NOD. Cg- /SzJ (NSG) mice results in clinical skin disease that progresses in severity.

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Article Synopsis
  • Reactive oxygen species, like superoxide and hydroperoxyl radicals, play a key role in breaking down environmental pollutants, including NTO, which is used in insensitive munitions and can contaminate water sources.
  • A computational study revealed that NTO decomposes in water through mechanisms initiated by these radicals, leading to the formation of various byproducts, including nitrous acid and nitrogen gas.
  • The research shows that the anionic form of NTO is more reactive with hydroperoxyl radicals, and sunlight can enhance the degradation process, ultimately converting NTO into simpler inorganic compounds.
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BACKGROUND Among patients with ICA stenosis, there are some cases with elevated, undisrupted, and diminished cerebral blood flow (CBF). The aim of this study was to assess the influence of ICA stenosis treatment on postoperative CBF changes in relation to preoperative CBF values. MATERIAL AND METHODS We qualified 58 patients ≥65 years old (28 males, 30 females, mean age 71.

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Data on Henry's law constants make it possible to systematize geochemical conditions affecting atmosphere status and consequently triggering climate changes. The constants of Henry's law are desired for assessing the processes related to atmospheric contaminations caused by pollutants. The most important are those that are capable of long-term movements over long distances.

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  • Dielectric capacitors, especially those made from polymers, are essential for electronics and energy storage due to their flexibility and efficient performance.
  • A new polymer thin film capacitor design, which incorporates layers of 2D nanofillers (Mica or -BN nanosheets) alongside poly(vinylidene fluoride) and poly(methyl methacrylate), has been developed, offering significantly increased energy density and efficiency.
  • The application of density functional theory helps validate the improvements in permittivity, suggesting that these 2D nanofillers could lead to versatile enhancements in high energy density capacitor design for various modern applications like electric vehicles.
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  • Hydroxyl radicals, created by sunlight in aquatic environments, can break down organic pollutants like NTO, a military chemical known for its high water solubility.
  • A study using computational methods examined how NTO decomposes when it interacts with hydroxyl radicals, revealing it involves multiple steps, starting with the radical adding to a C═N double bond.
  • This process generates various low-weight inorganic compounds, and the negatively charged form of NTO is found to be more reactive with hydroxyl radicals, highlighting their role in NTO's environmental breakdown.
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Dye-sensitized solar cells (DSCs) can provide a clean energy solution to growing energy demands. In order to have devices of high performance, sensitizers that are able to absorb in the near-infrared region (NIR) are needed. Stronger electron donors are needed for intramolecular charge-transfer sensitizers to access longer wavelength photons.

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Pregnancy is a well-known risk factor for venous insufficiency. However, even nulliparous women experience venous problems. Therefore, we aimed to assess the possible associations between the number of pregnancies, veins condition and treatment outcome in women with venous disease.

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Pelvic venous insufficiency is a common problem in multiparous women. Besides burdensome symptoms, it correlates with the development of venous disease in the lower limbs. Therefore, the sequential treatment of abdominal/pelvic before leg veins could improve treatment effectiveness.

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As fluorescence bioimaging has increased in popularity, there have been numerous reports on designing organic fluorophores with desirable properties amenable to perform this task, specifically fluorophores with emission in the near-infrared II (NIR-II) region. One such strategy is to utilize the donor-π-acceptor-π-donor approach (D-π-A-π-D), as this allows for control of the photophysical properties of the resulting fluorophores through modulation of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energy levels. Herein, we illustrate the properties of thienothiadiazole (TTD) as an effective acceptor moiety in the design of NIR emissive fluorophores.

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NIR dyes have become popular for many applications, including biosensing and imaging. For this reason, the molecular switch mechanism of the xanthene dyes makes them useful for in vivo detection and imaging of bioanalytes. Our group has been designing NIR xanthene-based dyes by the donor-acceptor-donor approach; however, the equilibrium between their opened and closed forms varies depending on the donors and spacer.

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Context: To apply the quantitative relationships "structure-endpoint" approach, the reliability of prediction is necessary but sometimes challenging to achieve. In this work, an attempt is made to accomplish the reliability of forecasts by creating a set of random partitions of data into training and validation sets, followed by constructing random models. A system of random models for a helpful approach should be self-consistent, giving a similar or at least comparable statistical quality of the predictions for models obtained using different splits of available data into training and validation sets.

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The formose reaction is a plausible prebiotic chemistry, famed for its production of sugars. In this work, we demonstrate that the Cannizzaro process is the dominant process in the formose reaction under many different conditions, thus necessitating a catalyst for the formose reaction under various environmental circumstances. The investigated formose reactions produce primarily organic acids associated with metabolism, a protometabolic system, and yield very little sugar left over.

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