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Recently, on an unbearably hot July afternoon in Delhi, I found myself standing barefoot in pilgrim reverence at the memorial of Mahatma Gandhi (1869-1948). This self-proclaimed Hindu has been called [...]

Polyurethanes (PUs) are a special class of polymeric materials that differ significantly from most other types of plastic in many aspects. They can be utilized in a wide range of products, including paints, coatings, elastomers, insulators, elastic fibers, and foams. PU foams are especially important as part of various convenience products. PU products often end up in landfills when they are no longer useful and can release toxic compounds when damaged by humans or microbes. Therefore, the ecotoxicological assessment of PU foams is essential. In this paper, five PU foam samples were prepared with different NCO indices (NCO-0.8, 0.9, 1.0, 1.1, and 1.2) and together with the Control sample (a previously tested non-toxic foam sample) were applied to develop toxicity tests procedure, while intentionally prepared Toxic foam has been used to verify the accuracy of the developed testing procedure. Two test organisms were successfully applied, Sinapis alba (white mustard) seeds and Escherichia coli (non-pathogenic) bacterial model organisms, and toxicity tests were adapted for the examination of PU-derived substances. Regarding Sinapis alba test, the highest NCO index (NCO-1.2) significantly reduced root length by 9.8 % compared to the Control sample. In the bacterial test, it was observed that the samples containing NCO-1.1 and NCO-1.2 had lower colony numbers (5.0 × 108 and 4.9 × 108 CFU/mL respectively) in comparison to the Control plate (9.6 × 108 CFU/mL). All in all, two toxicity tests were successfully adapted for PU foams, and both are applicable in their ecotoxicological assessment.

Abstract Background The percutaneous cannulation of the foramen ovale (FO) is implemented in treating trigeminal neuralgia, diagnosing temporal lobe epilepsy and biopsy petroclival lesions. This study dealt with the question whether it is possible to reach intracerebral structures with a puncture beyond the Gasserian Ganglion (GG) without bone destruction or perforating vascularity. Methods We considered the FO a natural keyhole and performed computer-simulated punctures through the right and left FO to eight intracerebral structures. Therefore, we took the Hartel and Submandibular (SM) approach as a starting point and planned trajectories with stereotactic planning software by using brain scans of ten patients. Results The simulated punctures with the Hartel approach directly reached the hippocampus (20 out of 20 trajectories), the lateral ventricle (15/20) and the amygdala (2/20). The pons was reached (20/20); however, the pontine vascularity was within the course. The trajectories to the thalamus (13/20) ran through the hippocampus or the mesencephalon. The simulated punctures with the SM approach directly reached the amygdala (18/20), the lateral ventricle (5/20) and the putamen (20/20). The trajectories to the nucleus caudatus (20/20) pierced the hippocampus, the putamen or the maxillary artery. The courses to the thalamus (7/20) ran through the hippocampus or the mesencephalon. The sinus cavernosus could not be reached with the Hartel or SM approach. Conclusions This study indicates that a percutaneous approach to the hippocampus, the lateral ventricle, the amygdala and the putamen is possible without harming major vessels or bone destruction. For a possible implementation of these trajectories in a clinical setting, it is necessary to prove these simulated punctures in cadaveric studies.

Activated carbon (AC) and biochar (BC) are porous materials with large surface areas and widely used in environmental and industrial applications. In this study, different types of AC and BC samples were produced from Sargassum sp. by a chemical activation and pyrolysis process and compared to commercial activated carbon samples. All samples were characterized using various techniques to understand their structure and functionalities. The metal content of the samples was characterized by using an inductively coupled optical emission spectrometer (ICP-OES). A toxicity test was applied to investigate the effect of AC/BC on organisms, where Sinapis alba seed and Escherichia coli bacteria-based toxicity tests were used. The results revealed that the samples did not negatively affect these two organisms. Thus, it is safe to use them in various applications. Therefore, the samples were tested as fillers in polyurethane composites and, thus, polyurethane-AC/BC samples were prepared. The amounts of AC/BC mixed into the polyurethane formulation were 1%, 2%, and 3%. Mechanical and acoustic properties of these composites were analyzed, showing that by adding the AC/BC to the system an increase in the compression strength for all the samples was achieved. A similar effect of the AC/BC was noticed in the acoustic measurements, where adding AC/BC enhanced the sound adsorption coefficient (α) for all composite materials. [ABSTRACT FROM AUTHOR]

Background: While left ventricular ejection fraction (LVEF) is the primary variable utilized for prognosis following myocardial infarction (MI), it is relatively indiscriminate for survival in patients with mildly reduced (> 40%) or preserved LVEF (> 50%). Improving risk stratification in patients with mildly reduced or preserved LVEF remains an unmet need, and could be achieved by using a combination approach using prognostically validated measures of left‐ventricular (LV) size, geometry, and function. Aims: The aim of this study was to compare the prognostic utility of a Combined Echo‐Score for predicting all‐cause (ACM) and cardiac mortality (CM) following MI to LVEF alone, including the sub‐groups with LVEF > 40% and LVEF > 50%. Methods: Retrospective data on 3094 consecutive patients with MI from 2013 to 2021 who had inpatient echocardiography were included, including both patients with ST‐elevation MI (n = 869 [28.1%]) and non‐ST‐elevation MI (n = 2225 [71.9%]). Echo‐Score consisted of LVEF < 40% (2 points) or LVEF < 50% (1 point), and 1 point each for left atrial volume index > 34 mL/m2, septal E/eʹ > 15, abnormal LV mass‐index, tricuspid regurgitation velocity > 2.8 m/s, and abnormal LV end‐systolic volume‐index. Simple addition was used to derive a score out of 7. Results: At a median follow‐up of 4.5 years there were 445 deaths (130 cardiac deaths). On Cox proportional‐hazards multivariable analysis incorporating significant clinical and echocardiographic predictors, Echo‐Score was an independent predictor of both ACM (HR 1.34, p <.001) and CM (HR 1.59, p <.001). Inter‐model comparisons of model 훘2, Harrel's C and Somer's D, and Receiver operating curves confirmed the superior prognostic value of Echo‐Score for both endpoints compared to LVEF. In the subgroups with LVEF > 40% and LVEF > 50%, Echo‐Score was similarly superior to LVEF for predicting ACM and CM. Conclusions: An Echo‐Score composed of prognostically validated LV parameters is superior to LVEF alone for predicting survival in patients with MI, including the subgroups with mildly reduced and preserved LVEF. This could lead to improved patient risk stratification, better‐targeted therapies, and potentially more efficient use of device therapies. Further studies should be considered to define the benefit of further investigation and treatment in high‐risk subgroups. [ABSTRACT FROM AUTHOR]

Polyurethane is the most important class of polymers. It contains several urethane bonds, which connect the building blocks of the polymer. Thus, the chemical recycling and the degradation of the polymer depend on the strength of the urethane bond. To better understand polyurethane degradation at the molecular level, three model systems were created, carbamic acid, methyl N-methylcarbamate, and phenyl N-phenyl carbamate, and studied by using computational chemical tools. Each of the model compounds contained one urethane bond. Thus, the effect of various functional groups around this motif can be studied by comparing the corresponding bond dissociation enthalpies (BDEs) within these compounds. The BDEs were computed by using the B3LYP density functional theory (DFT) method in combination with the 6-31G(d) basis set in the gas phase. It was found that in the case of phenyl Nphenyl carbamate, the degradation is more probable because the corresponding BDEs are lower than in the other two compounds. [ABSTRACT FROM AUTHOR]