In the North of Brazil (Pará and Amazonas states) the leaves of the plant Talinum triangulare (popular: cariru) replace spinach as food. From a phytochemical point of view, they are rich in compounds ...of the group of pheophytins. These substances, related to chlorophyll, have photophysical properties that give them potential application in photodynamic therapy. Human serum albumin (HSA) is one of the main endogenous vehicles for biodistribution of molecules by blood plasma. Association constants and thermodynamic parameters for the interaction of HSA with pheophytin from Talinum triangulare were studied by UV-Vis absorption, fluorescence techniques, and molecular modeling (docking). Fluorescence quenching of the HSA's internal fluorophore (tryptophan) at temperatures 296 K, 303 K, and 310 K, resulted in values for the association constants of the order of 10⁴ L∙mol(-1), indicating a moderate interaction between the compound and the albumin. The negative values of ΔG° indicate a spontaneous process; ΔH° = 15.5 kJ∙mol(-1) indicates an endothermic process of association and ΔS° = 0.145 kJ∙mol(-1)∙K(-1) shows that the interaction between HSA and pheophytin occurs mainly by hydrophobic factors. The observed Trp fluorescence quenching is static: there is initial non-fluorescent association, in the ground state, HSA:Pheophytin. Possible solution obtained by a molecular docking study suggests that pheophytin is able to interact with HSA by means of hydrogen bonds with three lysine and one arginine residues, whereas the phytyl group is inserted in a hydrophobic pocket, close to Trp-214.
With the exponential increase in heterogeneous wireless networks today, there has been a growing interest from the academic community for issues related to handover problems. The main objective of ...this paper is to evaluate the quality of service and performance of a device with a dual interface that connects simultaneously to two heterogeneous networks with no competition in the exchange of packets between them. It is a proposal to solve the mitigation of handover impacts. The tool used for evaluation was the Network Simulator 2. The results showed a better use of the band in comparison to the scenario using a traditional mobile device.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Photoexcitation of gold nanoparticles in their plasmon transition around 530 nm provides the means to carry high-energy reactions at room temperature. In the case of dicumyl peroxide (with activation ...energy of 34.3 kcal/mol) the reaction occurs in less than 1 min under 532 nm laser excitation. The results suggest that the peroxide is exposed to temperatures of ∼500 °C for submicrosecond times, and provides a guide as to which type of organic reactions may benefit from plasmon-mediated energy delivery.
Whether fresh or salty, water is a unique resource, a continuum interlinked by the hydrological cycle. It forms a complex system connected to the landscape. When the landscape is altered, water flows ...and their benefits are impacted. Degraded land compromises water resources. The governance and management of landscape and water resources are handled in a fragmented manner and in separate contexts. The Source-to-Sea approach offers an integrative vision based on systems thinking that focuses its concerns on the interaction among parts, flows, and processes. It proposes a framework for the governance and management of freshwater and marine water but does not bring the landscape into the context of the approach. This research used an analytical-deductive method to explore the interactions and connections between the Source-to-sea approach, landscape concepts and approaches, and the guidelines of the European Landscape Convention. The main objective was to identify and assess the feasibility of integrating these elements. The integration resulted in a governance and management approach termed the S2S Landscape approach. It is grounded in systems thinking, practical learning, active participation, and adaptive governance and management, providing an integrated vision between landscape and water. The approach includes four essential steps (Comprehension, Involvement, Planning, and Execution and Monitoring) that address the complex connections that freshwater and marine water maintain in the landscape, considering physical, biological, socio-environmental, and economic aspects across all segments, from the land to the open sea. This S2S Landscape approach may be the path to address the challenges of governance and sustainable management of resources in an interconnected and constantly changing world.
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•It focuses on landscape-water interfaces through the lens of the hydrological cycle.•Source-to-Sea Landscape Approach unifies land-water and policy frameworks.•Scenarios in the S2S Landscape help anticipate changes and navigate uncertainties.•As S2S Landscape's learning increases, the scale expands, fostering a dynamic cycle.•It encompasses systems thinking, innovations, participation, and adaptive governance.
This systematic review and meta-analysis aimed to determine the magnitude of the effect of combined exercise training on glucose metabolism markers, adipokines, and inflammatory cytokines in ...non-diabetic sedentary adults. PubMed, Web of Science, Scopus, Cochrane Library electronic databases and reference lists of included studies were explored for randomized controlled trials (RCTs) that included physically inactive adults and provided combined training interventions (aerobic plus resistance exercise). Effects on fasting glucose and insulin, Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), HbA1c, adiponectin, leptin, IL-6, TNF-α, and C-reactive protein (CRP) in exercise vs control groups were analyzed using random effects meta-analysis. The Cochrane Risk of Bias Tool for Randomized Trials 2.0 (RoB 2) was used to assess the risk of bias. A total of 24 RCTs were included in the quantitative analysis. Combined exercise training significantly decrease fasting glucose (standardized mean difference, SMD: - 0.474, 95% CI - 0.829, - 0.120, p = 0.009, 35 study arms), fasting insulin (SMD: - 1.024, 95% CI - 1.502, - 0.545, p < 0.001, 27 study arms), HOMA-IR (SMD: - 0.946, 95% CI - 1.450, - 0.442, p < 0.001, 23 study arms), TNF-α (SMD: - 0.972, 95% CI - 1.361, - 0.582, p < 0.001, 10 study arms), and CRP (SMD: - 0.507, 95% CI - 0.818, - 0.196, p = 0.001, 14 study arms). No significant effects were observed for HbA1c, adiponectin, leptin, and IL-6 levels. Random effects meta-regression models by age, sex, and intervention length were not able to explain any of the variation in the effect size of HOMA-IR. Findings from this systematic review and meta-analysis suggest that combined exercise training improves some glucose metabolism markers and inflammatory parameters in sedentary adults without diabetes.
Monteiro, R. and Ferreira, J.C., 2020. Green infrastructure planning as a climate change and risk adaptation tool in coastal urban areas. In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues ...of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 889–893. Coconut Creek (Florida), ISSN 0749-0208. The green infrastructure of Setúbal is an environmental and land management planning tool that recognizes the territorial ecological systems and guides in a sustainable way the occupation and transformation of the territory, and it was developed based on three main elements – georeferenced-based information, a quantitative and qualitative analysis of the territory, and technical meetings. The green infrastructure of Setúbal covers about 90% of the municipality – including urban areas –, 30% more than the land covered by other protected areas restrictions owned by the municipality – Arrábida Natural Park, Natural Reserve of Sado Estuary and Natura 2000 Network. As a climate change adaptation tool, this instrument promotes the development of measures that encourages citizens to adopt actions that contribute to the municipality's resilience.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NMLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Selective laser melting has received a great deal of attention in recent years. Nevertheless, research has been mainly focused on the technical issues and their relationship with the final ...microstructure and monotonic properties. Fatigue behaviour has rarely been addressed, and the emphasis has been placed on high-cycle regimes. The aim of this paper is, therefore, to study, in a systematic manner, the cyclic plastic behaviour of AISI 18Ni300 maraging steel manufactured by selective laser melting. For this purpose, low-cycle fatigue tests, under fully-reversed strain-controlled conditions, with strain amplitudes ranging from 0.3% to 1.0%, were performed. After testing, fracture surfaces were examined by scanning electron microscopy to identify the main fatigue damage mechanisms. The analysis of results showed a non-Masing material, with a slight strain-softening behaviour, and non-linear response in both the elastic and plastic regimes. In addition, this steel exhibited a very low transition life of about 35 reversals, far below the values of conventional materials with equivalent monotonic mechanical properties, which can be attributed to the combination of high strength and low ductility. The total strain energy density, irrespective of strain amplitude, revealed itself to be a quite stable parameter throughout the lifetime. Finally, the SEM analysis showed for almost all the tested samples cracks initiated from the surface and inner defects which propagated through the rest of the cross section. A ductile/brittle fracture, with a predominance of brittle fracture, was observed in the samples, owing to the presence of defects which make it easier to spread the microcracks.
Green infrastructure planning has been receiving great attention since the end of the last century. Although green infrastructure has been known for its ability to respond to a wide range of ...environmental, social, and economic challenges, the concept and associated implementation measures are still being discussed among researchers, decision-makers, and practitioners. To help these discussions, several authors have identified green infrastructure planning principles to help these professional with planning procedures. However the perception of practitioners regarding these principles was never taken into consideration. Because of this, the purpose of this research is to learn about the priorities of urban planners regarding green infrastructure planning principles and their integration into spatial planning. To achieve this, an Analytic Hierarchy Process methodology was applied to urban planners working in the 17 municipalities of Lisbon Metropolitan Area, in order to prioritize the green infrastructure planning principles influencing GI design and development in urban areas. Experts were asked to prioritize eight primary green infrastructure planning principles: connectivity, multi-functionality, applicability, integration, diversity, multiscale, governance, and continuity. The results show that the most important green infrastructure planning principle for practitioners is connectivity, followed by multifunctionality and applicability. Both integration and multiscale principles were considered more important in municipalities with predominantly urban features.
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•Hybrid nanocomposites of SEBS/GnP/CNT were prepared by melt compounding.•The electrical conductivity was enhanced by 17 orders of magnitude.•The higher EMI-SE was 36.47 dB (99.98% ...attenuation) achieved in the SEBS/GnP/CNT.•Results confirm synergic effect between GnP and CNT regarding EMI-SE.
Hybrid nanocomposites of poly (styrene-b-ethylene-ran-butylene-b-styrene) (SEBS), graphene nanoplatelets (GnP), and carbon nanotubes (CNT) were successfully prepared by melt compounding for electromagnetic shielding applications. The morphologies of the carbon nanoadditives and nanocomposites were investigated by Raman spectroscopy, field emission gun scanning electron microscopy, and rheological analysis. DC electrical conductivity was assessed by two-probe and four-probe techniques. Electromagnetic interference shielding effectiveness, shielding mechanisms, and dielectric properties were conducted in the X-band microwave frequency range (8.2–12.4GHz). The results showed that CNT had a higher affinity with the matrix, and were better dispersed than GnP. SEBS/GnP/CNT nanocomposites induced an electrical conductivity increase of 17 orders of magnitude compared to the polymer matrix. The hybrid nanocomposites presented synergic effects on EMI-SE when compared to the single-component nanocomposites (SEBS/GnP and SEBS/CNT). The maximum EMI-SE of 36.47dB (reduction of 99.98% of the incident radiation) was achieved for the SEBS/GnP/CNT nanocomposite with 5/10wt.% of GnP/CNT, respectively. All the hybrid nanocomposites with CNT loadings equal to or higher than 8wt.% presented the required EMI-SE for commercial applications.
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