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Background: Despite improving algorithms, inappropriate shocks for supraventricular tachycardia (SVT) still occur in a significant number of patients with implantable cardioverter-defibrillators (ICDs). This makes the discovery of novel discriminators that use existing ICD hardware an attractive proposition.Objective: We hypothesized that the delay of activation onset from the device-detected, far-field electrogram (EGM) to the near-field, bipole EGM would allow the differentiation of ventricular tachycardias (VTs) from SVTs.Methods: Proof of principle was demonstrated by rapid pacing in the right atrium, right ventricle, and left ventricle in healthy patients undergoing atrial fibrillation ablation procedures (n = 17). Using real-life ICD recordings, the equivalent measurements were made in a derivation cohort (n = 26) and cutoff predictive values obtained. Finally, the selected values were validated in a separate group of recordings (n = 82).Results: In healthy patients, significant differences in the far-field to near-field EGM activation onsets were observed between right atrial (14.7 ± 2.7 ms), right ventricular (36.3 ± 8 ms), and left ventricular (57.8 ± 10.3 ms; P < .001) pacing. In the derivation ICD cohort, the median far-field to near-field onset delay was significantly shorter in SVT (24.5 ms; interquartile range, 15.3-47.5 ms) than in VT (118.5 ms; interquartile range, 102.5-131.5 ms) (P < .001). Using a cutoff of 100 ms in the validation cohort, SVT was successfully discriminated from VT with a sensitivity and specificity of 88% and a negative predictive value of 94.2%.Conclusion: The delay between far-field and near-field EGMs offers a potential new discrimination tool to reduce inappropriate ICD therapies and aid interpretation of single-lead device tracings. [ABSTRACT FROM AUTHOR]

Abstract: The hypothalamic-neurohypophysial system (HNS) controls diuresis and parturition through the release of arginine-vasopressin (AVP) and oxytocin (OT). These neuropeptides are chiefly synthesized in hypothalamic magnocellular somata in the supraoptic and paraventricular nuclei and are released into the blood stream from terminals in the neurohypophysis. These HNS neurons develop specific electrical activity (bursts) in response to various physiological stimuli. The release of AVP and OT at the level of neurohypophysis is directly linked not only to their different burst patterns, but is also regulated by the activity of a number of voltage-dependent channels present in the HNS nerve terminals and by feedback modulators. We found that there is a different complement of voltage-gated Ca2+ channels (VGCC) in the two types of HNS terminals: L, N, and Q in vasopressinergic terminals vs. L, N, and R in oxytocinergic terminals. These channels, however, do not have sufficiently distinct properties to explain the differences in release efficacy of the specific burst patterns. However, feedback by both opioids and ATP specifically modulate different types of VGCC and hence the amount of AVP and/or OT being released. Opioid receptors have been identified in both AVP and OT terminals. In OT terminals, μ-receptor agonists inhibit all VGCC (particularly R-type), whereas, they induce a limited block of L-, and P/Q-type channels, coupled to an unusual potentiation of the N-type Ca2+ current in the AVP terminals. In contrast, the N-type Ca2+ current can be inhibited by adenosine via A1 receptors leading to the decreased release of both AVP and OT. Furthermore, ATP evokes an inactivating Ca2+/Na+-current in HNS terminals able to potentiate AVP release through the activation of P2X2, P2X3, P2X4 and P2X7 receptors. In OT terminals, however, only the latter receptor type is probably present. We conclude by proposing a model that can explain how purinergic and/or opioid feedback modulation during bursts can mediate differences in the control of neurohypophysial AVP vs. OT release. [Copyright &y& Elsevier]

Abstract: The hydrolysis process suffered by vinylcaprolactam (VCL) monomer during polymerization and the way of avoiding it is a matter of considerable interest when the final material is used in biomedical applications. In this work, in order to study the hydrolysis process in the synthesis of VCL-based microgels, VCL was polymerized by emulsion polymerization in batch and semi-batch reactors by using N,N′-methylenebisacrylamide (BA) as cross-linker and potassium persulfate (KPS) as initiator. Moreover, the partial conversion evolutions of VCL and BA were analyzed by 1H NMR. The colloidal characterization was carried out by measuring the final average diameters as a function of temperature. The results showed that there were two competitive reactions (hydrolysis and propagation) in the polymerizations carried out in the absence of a buffer. However, VCL did not suffer hydrolysis by adding a buffer in the recipes. A new reliable method for the determination of the partial conversions was developed using the quantitative NMR method. The final cross-linked colloidal particles (microgel particles) obtained in the buffered reaction presented the conventional swelling de-swelling behavior corresponding to temperature sensitive microgels. [Copyright &y& Elsevier]

Nanofiltration is a process used to separate mineral salts from lactose, having previously removed the proteins by ultrafiltration. Both proteins and lactose can be used as raw materials to prepare a variety of products. In this paper, we studied the feasibility of demineralizing sweet whey obtained from the cheese industry of the Comunidad Valenciana (Spain) using membrane technologies. The NF200 membrane showed the highest volumetric flux and solute rejection values, whereas the DS-5 DL membrane showed the lowest values. The volumetric fluxes obtained with the NF200 and DS-5 DL membranes in these experiments with the ultrafiltered whey demonstrated significant differences between membranes. Concerning solute rejection, the highest values were obtained using the NF200 membrane. The chosen parameter to evaluate the demineralization capability was solute flux. In this way, the values obtained for chloride ion were 9.90 and 32.42 g/(m²·h) for the NF200 and DS-5 DL membranes, respectively, with the highest demineralization rates being achieved with the DS-5 DL membrane. [ABSTRACT FROM AUTHOR]

The hypothesis of rescuing FKBP12/RyR1 interaction and intracellular calcium homeostasis through molecular "reshaping" of FKBP12 was investigated. To this end, novel 4-arylthioalkyl-1-carboxyalkyl-1,2,3-triazoles were designed and synthesized, and their efficacy was tested in human myotubes. A library of 17 compounds (10a - n) designed to dock the FKBP12/RyR1 hot-spot interface contact residues, was readily prepared from free α-amino acids and arylthioalkynes using CuAAC "click" protocols amenable to one-pot transformations in high overall yields and total configurational integrity. To model nitro-oxidative stress, human myotubes were treated with the peroxynitrite donor SIN1, and evidence was found that some triazoles 10 were able to normalize calcium levels, as well as FKBP12/RyR1 interaction. For example, compound 10 b at 150 nM rescued 46% of FKBP12/RyR1 interaction and up to 70% of resting cytosolic calcium levels in human myotubes under nitro-oxidative stress. All compounds 10 analyzed showed target engagement to FKBP12 and low levels of cytotoxicity in vitro. Compounds 10b, 10c , 10h, and 10iR were identified as potential therapeutic candidates to protect myotubes in muscle disorders with underlying nitro-oxidative stress, FKBP12/RyR1 dysfunction and calcium dysregulation. Image 1 • Triazole ligands 10 bind to FKBP12 protein; calcium conductance regulation in ryanodine RyR1 channels. • Binding of FKBP12 to nitrosylated RyR1 enhanced by triazole ligands 10. • Cytosolic calcium levels rescued in human myotubes stressed by peroxynitrite donor SIN1. • Cysteine-1781 key residue on RyR1 for peptidyl-prolyl isomerase activity of FKBP12. [ABSTRACT FROM AUTHOR]

Nature-based solutions (NBS) can provide answers to the challenges that urban areas are currently facing, associated with urban densification and climate change. The benefits of NBS are recognized, and include improved quality of life, human health and air quality, amongst others. This study aims to assess how NBS can contribute to temperature attenuation and air quality improvement in the city of Eindhoven (The Netherlands), through the application of the state-of-the-art WRF-Chem online air quality modelling system. The city is thereby characterized in terms of air quality related data, such as climatology, atmospheric emissions and air pollutant concentrations. From this assessment, different NBS were selected according to city aspirations. The WRF-Chem model was applied for baseline and NBS scenarios over the study area with a spatial resolution of 1 km x 1 km and an hourly time resolution for August 2013. The baseline scenario (without NBS) was validated by comparing the model results with monitored data retrieved from the European air quality monitoring database, showing an adequate model performance. The scenario simulations (with NBS) were performed by changing the land use in the model setup, and results were compared with the baseline scenario. Reductions in hourly temperature values of approximately 1 °C and reductions in pollutant concentrations, namely nitrogen dioxide (NO 2), of approximately 10% were estimated after the application of the NBS in the Eindhoven study area. These results are particularly important to support public planners and decision-makers in understanding the effects and importance of NBS in their planning for more sustainable and resilient cities. [ABSTRACT FROM AUTHOR]

During the COVID-19 pandemic, many consumers increased their use of supplements that claimed to support immune health, including Ayurvedic preparations. The goal of this study was to analyze labeling compliance and online claims for Ayurvedic herbal supplements associated with the purported treatment of COVID-19. The physical product labels for 51 herbal supplements labeled as ginger, tulsi/holy basil, amla, vacha/calamus root, guduchi/giloy, cinnamon, ashwagandha, tribulus, or turmeric were assessed for U.S. regulatory compliance. Disease claims, structure/function claims, and general well-being claims were also examined. The online listings for products purchased online (n = 42) were examined for claims and for the presence of the required legal disclaimer. Collectively, 61% of products had at least one instance of noncompliance on the physical label. The most common violations included missing/noncompliant disclaimer (33%), noncompliant "Supplement Facts" label (29%), noncompliant statement of identity (27%) and noncompliant domestic mailing address or phone number (25%). Structure/function claims occurred more frequently in the online product listings (average of 5 claims per product) compared to the physical labels (average of 2 claims per product). Disease claims were observed for 38% of online product listings and on 8% of physical labels. The use of disease claims on herbal supplements is a significant concern for public health because it may lead consumers to delay seeking professional treatment for life-threatening diseases. Overall, this study revealed a lack of labeling compliance among Ayurvedic herbal supplements and a need for greater scrutiny and monitoring of online product listings. • Ayurvedic supplements were examined for labeling compliance and online claims. • Over half of the products had at least one labeling violation on the physical label. • One-third of products had a missing or noncompliant legal disclaimer. • 38% of online product listings and 8% of physical labels contained disease claims. • Labeling noncompliance and use of disease claims are major public health concerns. [ABSTRACT FROM AUTHOR]

Air pollution is nowadays a serious public health problem worldwide, especially in urban areas, due to high population density and intense anthropogenic activity. This paper aims to present the development of a modelling tool suitable for simulating multiscale air quality and health impacts - the modair4health system, and its application to an urban case study. The modair4health system includes the online model WRF-Chem, which provides meteorological and air quality fields from regional to urban scales, and the computational fluid dynamics model VADIS, which uses the urban WRF-Chem outputs to simulate the flow and pollutant dispersion in urban built-up areas. A health module based on World Health Organization (WHO) methodologies was also integrated into the system to quantify physical and economic health impacts resulting from air quality changes. The system was applied over a local case study, which represents one of the busiest road traffic areas of the city of Coimbra in Portugal, to assess its operationality in estimating NO 2 concentrations and health impacts, by testing two traffic management scenarios. This scenario analysis considered a 4-domain nesting approach, with the finer resolution (4 m) domain focusing on the local case study and on two simulation periods, for which short-term health impacts were estimated. Spatially, the air quality and health greatest benefits were simulated around roads, where higher emission reductions were estimated, but they were also strongly influenced by the urban structure, local weather and population affected. The modair4health system has revealed to be an important multiscale modelling tool for integrated air quality and health assessment, able to support decision makers by facilitating the choice of cost-effective air quality and health management strategies and decisions. Moreover, its user-friendly interface allows to quickly test other urban air pollution control policies and the easy adaptation and application to other case studies considering regional to local atmospheric influences. The modair4health multiscale modelling system is composed of two air quality models able to simulate atmospheric concentrations from regional/urban (WRF-Chem) to local (VADIS) scales, and a health module for estimating physical and economic health impacts caused by short and long-term human exposure to air pollutants. [Display omitted] • The developed modair4health modelling system is presented. • It is able to simulate air quality and health impacts on multiple scales. • The urban structure has a key role in flow variations and pollutant dispersion. • Greater traffic scenario benefits are expected in areas and periods with higher NO 2. • Integrated assessment tool to effectively support air pollution control policies. [ABSTRACT FROM AUTHOR]

Abstract The exopolysaccharide (EPS)-producing Lactobacillus mali CUPV271 and Leuconostoc carnosum CUPV411 were isolated from Spanish ropy apple must and slimy ham, respectively. The polymers were purified from bacterial cultures' supernatants and subjected to physicochemical and rheological characterization with the aim to evaluate their potential for future industrial utilization. Methylation analysis, Fourier-Transform Infrared Spectroscopy (FT-IR) and Nuclear Magnetic Resonance (NMR) revealed that both polymers were dextrans, partially branched at O -3 and O -4 positions of the main α-(1 → 6)- d -glucopyranose backbone. The molar masses of the EPS of L. mali and Lc. carnosum were of 1.23 × 108 g/mol and 3.58 × 108 g/mol, respectively. The bacterial strains were tested for binding to the human Caco-2 cell line in the presence and absence of their respective dextran, revealing that the EPS production by L. mali decreased the binding capacity of the bacterium while the adhesiveness of Lc. carnosum did not change. As the structure and molecular mass of both dextrans were comparable, other characteristics of the dextrans were studied to explain this behavior. Atomic force micrographs showed some differences at the supramolecular level, suggesting that the different spatial distribution of the dextrans might be on the basis of the results of the adhesion studies. Both polysaccharides resulted to be amorphous materials with T g around 226 °C and showed slightly different thermal degradation patterns. Rheologically, they showed to have a pseudoplastic behavior, but very different critical concentrations: 3.8% for the EPS of L. mali and 0.4% for that of Lc. carnosum. Graphical abstract Image Highlights • Two novel EPS-producer bacteria were isolated from ropy cider and slimy ham. • Both polysaccharides were dextrans with slightly different branching degrees. • The dextrans are amorphous and have pseudoplastic behavior. • The EPS produced by L. mali reduced the bacterial binding to Caco-2 cells. • This could be due to the different spatial distribution of both dextrans. [ABSTRACT FROM AUTHOR]

This paper aims to propose a novel Road Traffic Noise Model (RTNM), capable of dynamically assessing road traffic noise levels from reliable data (hourly traffic volumes and speed), supporting or replacing noise sensor networks, and addressing noise pollution concerns. RTNM is composed of two parts: i) the Vehicle Noise Specific Power model (for the assessment of the sound power level – L w of passenger cars, considering speed and motorization information) coupled with the CNOSSOS model (for the estimation of heavy-duty vehicles' L w); and ii) a sound propagation model (to evaluate noise levels at the receiver point). Inputs for the RTNM are retrieved from a radar installed in Aveiro city, Portugal, while the model estimations are validated by comparing them with levels recorded by a noise sensor installed close to the radar. It was found that the resulting noise estimations are robust, with associated mean absolute percentage errors not exceeding 5.8%. [ABSTRACT FROM AUTHOR]

Experimental and computational studies on dendrimers possessing a Fe(porphyrin) catalytic core and polyether dendritic arms show that these macromolecules promote efficiently the (2+1) cycloaddition between a model alkene and diazomethane. The reaction is kinetically efficient and competitive with smaller catalysts. Lower generations of dendrimers exhibit a normal hyperbolic kinetic behaviour, whereas third- and fourth-generation dendrimers show a sigmoidal kinetic profile, compatible with cooperative effects most likely due to aggregation phenomena. This behaviour resembles that observed for Fe(porphyrin) containing biomolecules such as cytochromes and haemoglobin. [ABSTRACT FROM AUTHOR]

Abstract: Conformationally restricted NADH peptidomimetics 4a–e, characterized by the presence of a (1,4-dihydronicotinamide)-(β-lactam) moiety, have been synthesized and used to study the Mg2+ cation-promoted asymmetric reduction of alkyl aroylformates in acetonitrile. Increasing the bulkiness of peripheral substituents at the nitrogen atom of the β-lactam ring, at the 1,4-dihydronicotinamide moiety, or at the aroylformate ester group, was found to cause weak but clearly detectable variations of the enantiomeric excess of the reaction. A rational for these observations was consistent with a chelated NADH/Mg2+/ArCOCO2R3 ternary complex model, according to DFT calculations computed at a B3LYP/6-31G∗ theory level. [Copyright &y& Elsevier]

Las Truchas deposits formed by contact metasomatism in a Mesozoic volcano-sedimentary sequence intruded by a batholith. Later, post-mineralization hydrothermal alteration affected minerals and magnetic properties. For this study, we sampled the host rocks and iron ores. The mineralogy and magnetic domain states of oxide minerals were characterized by reflected light and scanning electron microscopy together with rock magnetic experiments such as thermomagnetic measurements, frequency dependence of magnetic susceptibility, hysteresis, first-order-reversal-curves and UnMix curves. Qualitative and quantitative forward modelling of the subsurface structure was inferred by processing of magnetic anomaly maps. Induced and remanent magnetization (intensity and direction) and the Königsberger ratio were used as input parameters for the quantitative modelling process to adjust our calculated anomaly with the observed magnetic anomalies. We attempt to understand the geological factors that control the magnetic signatures, which can be used to improve the geological interpretation of magnetic studies. • Mineralization and tectonic frame are associated. • Optical microscopy and SEM observation of magnetic minerals. • Rock magnetic properties and definition of induced and remanent magnetization. • Qualitative and quantitative modelling of aeromagnetic anomalies. • Geologic models more reliable and use for exploration and exploitation planning. [ABSTRACT FROM AUTHOR]