SciCombinator

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In our society, the number of couples with advanced reproductive age seeking fertility treatment is increasing steadily. While the negative effect of female age on assisted reproductive technology (ART) outcomes is well established, the impact of paternal age needs to be clarified. We reviewed the current literature to determine whether advanced paternal age affects the results of ART and the health of resulting offspring. We found that the published literature is overall supportive of a positive association between advanced paternal age (>40 years) and semen quality deterioration. However, the existing evidence does not corroborate nor discard the influence of advanced paternal age on ART outcomes. Similarly, the effect of paternal age on the health of ART offspring remains equivocal, although data from naturallyconceived children clearly indicates that advanced paternal age increases the frequency of genetic, neurodevelopmental, and psychiatric diseases in the progeny. Noteworthy, the current literature is limited and subjected to bias due to the impact of maternal age as a critical confounder. Health care providers should discuss with concerned couples the available options to counteract the possible negative influence of advanced paternal age on ART outcomes and health of resulting offspring. These include identification and treatment of underlying conditions with potential negative long-term effects on fertility, sperm freezing at a young age, and use of antioxidant supplements for men at risk of excessive oxidative stress. Aged male partner from couples undergoing ART, in particular men of 50 years and older, should consider use of preimplantation genetic testing as a means to detect embryo abnormalities and select euploid embryos for transfer to the uterine cavity.

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Herein we report our high-volume single center experience with extraperitoneal robot-assisted radical prostatectomy (eRARP) in patients with prostate cancer (PCa).

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Treatment strategy for inoperable and metastatic urothelial carcinoma (mUC) has been revolutionized by the introduction of programmed cell death protein 1 (PD-1) and programmed cell death protein ligand (PD-L1) antibodies. During the last 3 decades treatment options were limited to chemotherapy, making further treatment of patients whose disease progressed under ongoing therapy or who were ineligible to receive cytotoxic therapy in the first place, nearly impossible.

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Among the vast number of recognition molecules, DNA ap-tamers generated from cell-SELEX exhibit unique properties for identifying cell membrane biomarkers, in particular pro-tein receptors on cancer cells. To integrate all recognition and computing modules within a single structure, a three-dimensional (3D) DNA-based logic gate nanomachine was constructed to target overexpressed cancer cell biomarkers with bispecific recognition. Thus, when the Boolean opera-tor “AND” returns a true value, it is followed by an “ON” signal when the specific cell type is presented. Compared with freely dispersed double-stranded DNA (dsDNA)-based molecular circuits, this 3D DNA nanostructure, termed DNA-logic gate triangular prism (TP), showed better identi-fication performance, enabling, in turn, better molecular targeting and fabrication of recognition nanorobotics.

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The microtubule-kinesin system is used to form nanostructures via microtubule gliding on a kinesin motor-coated surface. The microtubules can be easily assembled into micro- and nanostructures like circles and fibers using the streptavidin-biotin system. Furthermore, the microtubules can retain performance with kinesin motor movement, and their velocities are affected by different structures. By taking advantage of biological substances some structures, difficult to be fabricated by artificial processes, can be easily obtained.

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Nitric acid, a well-known sink of NOx gases in the atmosphere, has been found to be photoactive while adsorbed on tropospheric particles. When adsorbed onto semiconductive metal oxides, nitrate’s photochemical degradation can be interpreted as a photocatalytic process. Yet, the photolysis of nitrate ions on the surface of aerosols can also be initiated by changes in the symmetry of the ion upon adsorption. In this study, we use quantum chemistry to model the vibrational spectra of adsorbed nitrate on TiO2, a semiconductor component of atmospheric aerosols, and determine the kinetics of the heterogeneous photochemical degradation of nitrate under simulated solar light. Frequencies and geometry calculations suggest that the symmetry of chemisorbed nitrate ion depends strongly on coadsorbed water, with water changing the reactive surface of TiO2. Upon irradiation, surface nitrate undergoes photolysis to yield nitrogen-containing gaseous products including NO2, NO, HONO and N2O, in proportions that depend on relative humidity (RH). In addition, the heterogeneous photochemistry rate constant decreases an order of magnitude, from (5.7±0.1)×10-4 s-1 on a dry surface to (7.1±0.8)×10-5 s-1 when nitrate is coadsorbed with water above monolayer coverage. Little is known about the roles of coadsorbed water on the heterogeneous photochemistry of nitrates on TiO2, along with its impact on the chemical balance of the atmosphere. This work discusses the roles of water in the photolysis of surface nitrates on TiO2 and the concomitant renoxification of the atmosphere.

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Crystallization of oil droplets is critical in the processing and storage of lipid-based food and pharmaceutical products. Arrays of femtoliter droplets on a surface offer a unique opportunity to study surfactant free colloid-like systems. In this work, the crystal growth process in these confined droplets was followed by cooling a model lipid (trimyristin) from a liquid state by utilizing Synchrotron Small-Angle X-ray Scattering (SAXS). The measurements by SAXS demonstrated a reduced crystallization rate and a greater degree of supercooling required to trigger lipid crystallization in droplets, compared to bulk lipids. These results suggest that surface droplets crystallize in a stochastic manner. Interestingly, the crystallization rate is slower for larger femtoliter droplets, which may be explained by the onset of crystallization from the three-phase contact line. The larger surface nanodroplets exhibit a smaller ratio of droplet volume to the length of three-phase contact line, and hence slower crystallization rate.

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The tea tree is a perennial woody plant, and pruning is one of the most crucial cultivation measurements for tea plantation management. To date, the relationship between long-term pruning and metabolic flux enhancement in tea trees has not been studied. In this research, 11-year-old pruned tea trees from four different cultivars were randomly selected for transcriptome analysis and characteristic secondary metabolite analysis together with controls. The findings revealed that epigallocatechin gallate (EGCG) accumulation in pruned tea trees was significantly higher than in unpruned tea trees. SCPL1A expression (encoding a class of serine carboxypeptidase), which has been reported to have a catalytic ability during EGCG biosynthesis, together with LAR encoding leucoanthocyanidin reductase, was upregulated in the pruned tea trees. Moreover, metabolic flux enhancement and transcriptome analysis revealed low EGCG accumulation in the leaves of unpruned tea trees. Because of the bitter and astringent taste of EGCG, these results provide a certain understanding to the lower bitterness and astringency in teas from “ancient tea trees”, growing in the wild with no trimming, than teas produced from pruned plantation trees.

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Charged thiourea derivatives containing one and two methylated or octylated pyridinium ion centers and a tetraarylborate or triflate counteranion are reported. These novel catalysts are much more active in the Friedel‒Crafts reactions of trans-β-nitroalkenes with N-methylindoles than the privileged N,N'-bis(3,5-bis(trifluoromethyl)phenyl)thiourea (i.e., Schreiner’s thiourea) by up to 2-3 orders of magnitude. A previously reported UV-Vis spectroscopic method by Kozlowski et al. was exploited to rationalize their reactivity order along with non-charged analogs. These results offer a new design strategy for organocatalysts by introducing positively charged centers without adding additional N-H, O-H, or S-H hydrogen bond donor sites.

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A daily-integrated emission factor (EF) method was applied to data from three near-road monitoring sites to identify variables that impact traffic related pollutant concentrations in the near-road environment. The sites were operated for twenty months in 2015-2017, with each site differing in terms of design, local meteorology, and fleet compositions. Measurement distance from the roadway and local meteorology were found to affect pollutant concentrations irrespective of background subtraction. However, using emission factors mostly accounted for the effects of dilution and dispersion, allowing inter-site differences in emissions to be resolved. A multiple linear regression model that included predictor variables such as fraction of larger vehicles (>7.6 m in length; i.e., heavy-duty vehicles), vehicle speed, and ambient temperature accounted for inter-site variability of the fleet average NO, NOx, and particle number EFs (R2:0.50-0.75), with lower model performance for CO and black carbon (BC) EFs (R2:0.28-0.46). NOx and BC EFs were affected more than CO and particle number EFs, by the fraction of larger vehicles, which also resulted in measurable weekday/weekend differences. Pollutant EFs also varied with ambient temperature and because there was little seasonal changes in fleet composition, this was attributed to changes in fuel composition and/or post-tailpipe transformation of pollutants.