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The ionic liquid 1-dodecyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, termed [C12mim][(CF3SO2)2N], has been studied for several applications, such as gas solubility, phase equilibrium studies in binary and ternary systems, the separation of butan-1-ol/water, and thermal energy storage, with studies on its nanostructure and thermophysical properties having been performed. The main justification for these studies is that increasing the length of the carbon chain also increases the heat capacity, which endows [C12mim][(CF3SO2)2N] with excellent thermal properties. These thermal properties make [C12mim][(CF3SO2)2N] a strong potential choice for use as the thermal energy storage (TES) and heat transfer fluid (HTF) media in solar thermal power plant systems, especially when compared to traditional media (i.e., thermal oils). In order to confirm this possibility, in this study we measured the density, speed of sound, viscosity, and thermal conductivity of [C12mim][(CF3SO2)2N] in the temperature range 293.15 < T/K < 343.15 and at P= 0.1 MPa. In addition, we studied its ionanofluid with graphene by measuring its viscosity and thermal conductivity (for the first time), aiming to confirm to the fact that long alkyl chains in alkylimidazolium liquids may improve the stabilization of the nanoparticle dispersion in the nanofluid. Our results demonstrate that [C12mim][(CF3SO2)2N] and its ionanofluid with graphene are both Newtonian fluids. It was also determined that the transport properties of [C12mim][(CF3SO2)2N] are not affected (within the mutual uncertainty of the experiments) by the presence of nanographene platelets in a stable dispersion.

DNA origami nanotechnology has great potential in multiple fields including biomedical, biophysical, and nanofabrication applications. However, current production pipelines lead to single-use devices incorporating a small fraction of initial reactants, resulting in a wasteful manufacturing process. Here, we introduce two complementary approaches to overcome these limitations by recycling the strand components of DNA origami nanostructures (DONs). We demonstrate reprogramming entire DONs into new devices, reusing scaffold strands. We validate this approach by reprogramming DONs with complex geometries into each other, using their distinct geometries to verify successful scaffold recycling. We reprogram one DON into a dynamic structure and show both pristine and recycled structures display similar properties. Second, we demonstrate the recovery of excess staple strands postassembly and fold DONs with these recycled strands, showing these structures exhibit the expected geometry and dynamic properties. Finally, we demonstrate the combination of both approaches, successfully fabricating DONs solely from recycled DNA components.

•Most hemolysis events in difficult-to-treat patients with PNH on pegcetacoplan were manageable without pegcetacoplan discontinuation.•Higher disease activity at baseline may indicate patients at increased risk of hemolysis.

Ionic liquids with the dicyanamide anion, namely, with 1-alkyl-imidazolium cations, have been receiving attention recently due to their potential applications. The utilization of these liquids as heat transfer fluids, specifically in small heat exchangers and microchannels for microprocessor cooling, is presently deemed highly feasible, as it can be both more efficient and environmentally acceptable. The design of a heat transfer equipment that makes use of fluids requires knowledge of their thermophysical properties. In this regard, dispersions of nanoparticles have been extensively studied in recent years to improve thermal conductivity or obtain desirable optical properties. IoNanofluids is what we have taken to name the result of such dispersions in ionic liquids. In this paper, we report measurements of the thermal conductivity and viscosity of the IoNanofluid of 1-ethyl-3-methylimidazolium dicyanamide, [C2mim][N(CN)2], with 0.5% mass fraction of TiO2nanoparticles (diameter 20 nm) in the temperature range (293 < T/K < 343), at P= 0.1 MPa. Reasonable enhancements were found for thermal conductivity and viscosity, which were temperature-dependent. The IoNanofluid was found to behave as a non-Newtonian fluid in most of the temperature range studied. A discussion about the possible use of this IoNanofluid as a heat transfer fluid shows that it has very promising properties to be used in heat transfer applications.

Identifying the lowest energy isomers in large clusters is a major challenge. Here, we introduce the Growth Pattern Algorithm (GrowPAL), a new approach that generates initial seeds composed of n+1atoms from the system with natoms through an interstitial-type addition (I-type) mechanism. We evaluated the effectiveness of GrowPAL on Lennard-Jones (LJ) clusters with up to n= 80 atoms, verifying the algorithm’s ability to find challenging minima such as LJ38and the partially icosahedral LJ69with fewer optimizations than existing methods. In addition, we discuss the advantages and limitations of GrowPAL using our deconstruction scheme, which identifies “forebears” structures to study growth pathways. Having evaluated the strengths and weaknesses of GrowPAL, we employed it to explore Sutton-Chen clusters containing 5 to 80 atoms, uncovering three new lowest energy forms. We then applied GrowPAL to boron clusters containing 8 to 15 atoms, successfully identifying all reported minima. Overall, GrowPAL offers a practical solution for efficiently identifying global minima in hierarchical systems, thereby reducing computational costs.

Supplemental Digital Content is Available in the Text.Angiotensin (Ang)-(1-7) is a cardioprotective peptide of the renin-angiotensin system. Prepuberty has been considered as a later susceptible window of development, and stressful factors in this life phase can induce chronic diseases in adulthood. We aimed to investigate whether the treatment with Ang-(1-7) during the prepuberty could attenuate the development of hypertension and cardiac injury in adult spontaneously hypertensive rats (SHRs). SHRs were treated with Ang-(1-7) (24 μg/kg/h) from age 4 to 7 weeks. Systolic blood pressure was measured by tail-cuff plethysmography up to 17th week. Thereafter, echocardiography was performed, and the rats were euthanized for the collection of tissues and blood. Ang-(1-7) did not change the systolic blood pressure but reduced the septal and posterior wall thickness, and cardiomyocyte hypertrophy and fibrosis in SHR. In addition, Ang-(1-7) reduced the gene expression of atrial natriuretic peptide and brain natriuretic peptide, increased the metalloproteinase 9 expression, and reduced the extracellular signal-regulated kinases 1/2 phosphorylation. Ang-(1-7) also prevented the reduction of Mas receptor but did not change the protein expression of angiotensin-converting enzyme, angiotensin-converting enzyme 2, AT1, and AT2. The treatment with Ang-(1-7) decreased the malondialdehyde (MDA) levels and increased superoxide dismutase-1 and catalase activities and protein expression of catalase. Our findings demonstrate that the treatment of SHR with Ang-(1-7) for 3 weeks early in life promotes beneficial effects in the heart later in life, even without altering blood pressure, through mechanisms involving the reduction of oxidative stress and ERK1/2 phosphorylation. In addition, this study supports the prepuberty as an important programming window.

Cutting-edge network architectures and solutions are needed to empower operators to address capacity demands in metro and access networks efficiently. The horseshoe topology, along with similar topologies, is commonly employed in metro-aggregation segments due to its compatibility with the hub-and-spoke traffic pattern present in these networks and the survivability that they can provide. A filterless architecture can enhance cost-effectiveness by replacing active elements with passive components. Moreover, supporting coherent-based point-to-multipoint transceivers—enabled by digital subcarrier multiplexing (DSCM)—can yield additional cost savings. It is noteworthy that telecommunication network topologies often evolve to accommodate more end (leaf) nodes, extending the original horseshoe with spurs or small and short trees. This paper targets these types of networks and proposes combining the utilization of coherent pluggable transceivers leveraging DSCM to guarantee transparent communication between the hub and leaf nodes while adopting different filterless node architectures with selective amplifier deployment. Moreover, it discusses the potential advantages of the architecture using an exact optimization framework tailored to various network sizes and scenarios, which accounts for the amplifiers’ placement and the available types of power splitters/combiners/couplers. The results demonstrate that strategically deploying add/drop and express amplifiers, along with optimizing coupler ratios, can effectively meet design requirements while minimizing the number of optical amplifiers required.

While computational thinking arises as an essential skill worldwide, formal primary and secondary education in Latin America rarely incorporates mechanisms to develop it in their curricula. The extent to which students in the region acquire computational thinking skills remains largely unknown. To start addressing this void, this article presents findings from a cross sectional study that characterizes the computational thinking abilities of incoming students at a Chilean university with a strong emphasis on STEM disciplines. Based on more than 500 responses, this study provides evidence of significant inequalities in computational thinking across gender, type of school (private or no), and prior programming knowledge. The discussion offers insights into how these disparities relate to contextual factors of the country, such as a highly socio-economically segregated educational system, public policies focused mainly on technology access, and heavy reliance on voluntary initiatives, to develop computational thinking. The findings can enlighten upcoming research endeavors and formulate strategies to create a more equitable field for students entering STEM degrees in nations facing similar circumstances.

In this Letter, we demonstrate the coexistence of a prototype 200 Gb/s symmetrical coherent point-to-multipoint (PtMP) system with a 50G-PON prototype over 20 km of standard single mode fiber for next generation optical access networks. The optical path loss (OPL) of the coherent PtMP prototype exceeds 30.6 dB at 1544 nm in both directions, thus exceeding the N1 OPL class requirements. The prototype also achieves N1 OPL class requirements over the entire C-band. The experiments show full compatibility between the two systems, enabled by the wavelength plan. We also evaluate the ability of the coherent-PtMP system to support imbalanced terminations in terms of OPLs, to meet the already deployed optical access network requirements. The coherent-PtMP system flexibility is demonstrated through the reconfiguration of its subcarriers to transmit a maximum of 400 Gb/s in a single direction.

The complexity of current and future electricity networks demands the use of more accurate models to solve the Transmission Network Expansion Planning (TNEP) problem. To deal with this issue, formulations based on AC network equations have been proposed by the research community. Although the AC formulations exist, they do not work with problems with a large number of candidate transmission paths, different planning scenarios due to convergence issues or infeasible solutions. Also, it has been difficult for the power system community to be aware of the real advantages and disadvantages of the existing approaches due to the lack of rigorous and fair comparisons among them. In this research work, a full non-convex AC formulation to solve the TNEP problem is proposed. It considers in an integrated fashion reactive power expansion, the (N-1) contingency criterion and operational costs. The formulation is solved by an improved non-convex optimization algorithm in a two-stage approach. Also, a fair and rigorous quantitative and qualitative comparison among the proposed approach and other state-of-art metaheuristics and mathematical programming methods has been performed. Simulation results show that the proposed formulation and solution method are superior to other approaches with respect to reliability and suitability for cases with large search spaces and different scenarios. Results are shown for four test systems, namely the Garver 6-bus system, the IEEE 24-bus system, the IEEE 118-bus system, and a modified version of the IEEE 300-bus system.

Marine dissolved organic matter (DOM) presents key thermodynamic properties that are not yet fully constrained. Here, we report the distribution of binding sites occupied by protons (i.e., proton affinity spectra) and parametrize the median intrinsic proton binding affinities (log K̅H) and heterogeneities (m), for DOM samples extracted from the North Atlantic. We estimate that 11.4 ± 0.6% of C atoms in the extracted marine DOM have a functional group with a binding site for ionic species. The log K̅Hof the most acidic groups was larger (4.01–4.02 ± 0.02) than that observed in DOM from coastal waters (3.82 ± 0.02), while the chemical binding heterogeneity parameter increased with depth to values (m1= 0.666 ± 0.009) ca. 10% higher than those observed in surface open ocean or coastal samples. On the contrary, the log K̅Hfor the less acidic groups shows a difference between the surface (10.01 ± 0.08) and deep (9.22 ± 0.35) samples. The latter chemical groups were more heterogeneous for marine than for terrestrial DOM, and m2decreased with depth to values of 0.28 ± 0.03. Binding heterogeneity reflects aromatic carbon compounds’ persistence and accumulation in diverse, low-abundance chemical forms, while easily degradable low-affinity groups accumulate more uniformly in the deep ocean.

Symptoms of anaemia due to clinically significant extravascular haemolysis can affect patients with paroxysmal nocturnal haemoglobinuria (PNH) treated with C5 inhibitors (ravulizumab or eculizumab). The aim of this study was to assess the efficacy and safety of danicopan (ALXN2040), an investigational, first-in-class, oral complement factor D inhibitor, as add-on therapy to ravulizumab or eculizumab in patients with PNH and clinically significant extravascular haemolysis.

Clasificar al personal de 2 instituciones de referencia para la atención de la COVID-19 en Antioquia según la intensidad de los síntomas ansiosos y depresivos y determinar los factores asociados con estas clases.

Biomolecular nanotechnology has helped emulate basic robotic capabilities such as defined motion, sensing, and actuation in synthetic nanoscale systems. DNA origami is an attractive approach for nanorobotics, as it enables creation of devices with complex geometry, programmed motion, rapid actuation, force application, and various kinds of sensing modalities. Advanced robotic functions like feedback control, autonomy, or programmed routines also require the ability to transmit signals among subcomponents. Prior work in DNA nanotechnology has established approaches for signal transmission, for example through diffusing strands or structurally coupled motions. However, soluble communication is often slow and structural coupling of motions can limit the function of individual components, for example to respond to the environment. Here, we introduce an approach inspired by protein allostery to transmit signals between two distal dynamic components through steric interactions. These components undergo separate thermal fluctuations where certain conformations of one arm will sterically occlude conformations of the distal arm. We implement this approach in a DNA origami device consisting of two stiff arms each connected to a base platform via a flexible hinge joint. We demonstrate the ability for one arm to sterically regulate both the range of motion and the conformational state (latched or freely fluctuating) of the distal arm, results that are quantitatively captured by mesoscopic simulations using experimentally informed energy landscapes for hinge-angle fluctuations. We further demonstrate the ability to modulate signal transmission by mechanically tuning the range of thermal fluctuations and controlling the conformational states of the arms. Our results establish a communication mechanism well-suited to transmit signals between thermally fluctuating dynamic components and provide a path to transmitting signals where the input is a dynamic response to parameters like force or solution conditions.

We present an improved algorithm to solve the near-congruence problem for rigid molecules and clusters based on the iterative application of assignment and alignment steps with biased Euclidean costs. The algorithm is formulated as a quasi-local optimization procedure with each optimization step involving a linear assignment (LAP) and a singular value decomposition (SVD). The efficiency of the algorithm is increased by up to 5 orders of magnitude with respect to the original unbiased noniterative method and can be applied to systems with hundreds or thousands of atoms, outperforming all state-of-the-art methods published so far in the literature. The Fortran implementation of the algorithm is available as an open source library (https://github.com/qcuaeh/molalignlib) and is suitable to be used in global optimization methods for the identification of local minima or basins.

Rezafungin is a next-generation, once-a-week echinocandin in development for the treatment of candidaemia and invasive candidiasis and for the prevention of invasive fungal disease caused by Candida, Aspergillus, and Pneumocystisspp after blood and marrow transplantation. We aimed to compare the efficacy and safety of intravenous rezafungin versus intravenous caspofungin in patients with candidaemia and invasive candidiasis.

The interactions of cells with signaling molecules present in their local microenvironment maintain cell proliferation, differentiation, and spatial organization and mediate progression of diseases such as metabolic disorders and cancer. Real-time monitoring of the interactions between cells and their extracellular ligands in a three-dimensional (3D) microenvironment can inform detection and understanding of cell processes and the development of effective therapeutic agents. DNA origami technology allows for the design and fabrication of biocompatible and 3D functional nanodevices via molecular self-assembly for various applications including molecular sensing. Here, we report a robust method to monitor live cell interactions with molecules in their surrounding environment in a 3D tissue model using a microfluidic device. We used a DNA origami cell sensing platform (CSP) to detect two specific nucleic acid sequences on the membrane of B cells and dendritic cells. We further demonstrated real-time detection of biomolecules with the DNA sensing platform on the surface of dendritic cells in a 3D microfluidic tissue model. Our results establish the integration of live cells with membranes engineered with DNA nanodevices into microfluidic chips as a highly capable biosensor approach to investigate subcellular interactions in physiologically relevant 3D environments under controlled biomolecular transport.

We propose a numerical method to approximate the scattering amplitudes for the elasticity system with a non-constant matrix potential in dimensions d=2and 3. This requires to approximate first the scattering field, for some incident waves, which can be written as the solution of a suitable Lippmann-Schwinger equation. In this work we adapt the method introduced by Vainikko (Res Rep A 387:3–18, 1997) to solve such equations when considering the Lamé operator. Convergence is proved for sufficiently smooth potentials. Implementation details and numerical examples are also given.

In the PEGASUS trial, the complement C3 inhibitor, pegcetacoplan, showed superiority to eculizumab in improving haematological outcomes in adult patients with paroxysmal nocturnal haemoglobinuria and suboptimal response to eculizumab at 16 weeks. The aim of the open-label period was to evaluate the long-term efficacy and safety of pegcetacoplan through to 48 weeks.

Molecular dynamics simulations are often used to provide feedback in the design workflow of DNA nanostructures. However, even with coarse-grained models, the convergence of distributions from unbiased simulation is slow, limiting applications to equilibrium structural properties. Given the increasing interest in dynamic, reconfigurable, and deformable devices, methods that enable efficient quantification of large ranges of motion, conformational transitions, and mechanical deformation are critically needed. Metadynamics is an automated biasing technique that enables the rapid acquisition of molecular conformational distributions by flattening free energy landscapes. Here we leveraged this approach to sample the free energy landscapes of DNA nanostructures whose unbiased dynamics are nonergodic, including bistable Holliday junctions and part of a bistable DNA origami structure. Taking a DNA origami-compliant joint as a case study, we further demonstrate that metadynamics can predict the mechanical response of a full DNA origami device to an applied force, showing good agreement with experiments. Our results exemplify the efficient computation of free energy landscapes and force response in DNA nanodevices, which could be applied for rapid feedback in iterative design workflows and generally facilitate the integration of simulation and experiments. Metadynamics will be particularly useful to guide the design of dynamic devices for nanorobotics, biosensing, or nanomanufacturing applications.

The ability to apply and measure high forces (>10 pN) on the nanometer scale is critical to the development of nanomedicine, molecular robotics, and the understanding of biological processes such as chromatin condensation, membrane deformation, and viral packaging. Established force spectroscopy techniques including optical traps, magnetic tweezers, and atomic force microscopy rely on micron-sized or larger handles to apply forces, limiting their applications within constrained geometries including cellular environments and nanofluidic devices. A promising alternative to these approaches is DNA-based molecular calipers. However, this approach is currently limited to forces on the scale of a few piconewtons. To study the force application capabilities of DNA devices, we implemented DNA origami nanocalipers with tunable mechanical properties in a geometry that allows application of force to rupture a DNA duplex. We integrated static and dynamic single-molecule characterization methods and statistical mechanical modeling to quantify the device properties including force output and dynamic range. We found that the thermally driven dynamics of the device are capable of applying forces of at least 20 piconewtons with a nanometer-scale dynamic range. These characteristics could eventually be used to study other biomolecular processes such as protein unfolding or to control high-affinity interactions in nanomechanical devices or molecular robots.

Ionic liquids have proved to be excellent heat transfer fluids and alternatives to common HTFs used in industries for heat exchangers and other heat transfer equipment. However, its industrial utilization depends on the cost per kg of its production, to be competitive for industrial applications with biphenyl and diphenyl oxide, alkylated aromatics, and dimethyl polysiloxane oils, which degrade above 200 °C and possess some environmental problems. The efficiency of a heat transfer fluid depends on the fundamental thermophysical properties influencing convective heat transfer (density, heat capacity, thermal conductivity, and viscosity), as these properties are necessary to calculate the heat transfer coefficients for different heat exchanger geometries. In Part 1, the thermophysical properties of pure 1-ethyl-3-methylimidazolium methanesulfonate [C2mim][CH3SO3] (CAS no. 145022-45-3), (ECOENG 110), produced by BASF, under the trade name of Basionics ST35, with an assay ≥97% with ≤0.5% water and ≤2% chloride (Cl–), were presented, for temperatures slightly below room temperature and up to 355 K. In this paper, we report the thermophysical properties of mixtures of [C2mim][CH3SO3] with water, in the whole concentration range, at P= 0.1 MPa. The properties measured were density and speed of sound (293.15 < T/K < 343.15), viscosity, electrical and thermal conductivities, refractive index (293.15 < T/K < 353.15), and infinite dilution diffusion coefficient of the ionic liquid in water (298.15 K). The properties for the mixture like the isobaric expansion coefficient, the isentropic compressibility, apparent molar volumes, apparent molar isentropic compressions, and the thermodynamic excess properties, like excess molar volume, excess molar isobaric expansion and isentropic compression, excess viscosity, thermal conductivity, molar refraction, and infinite dilution diffusion coefficients of the cation, anion and other common anions in ionic liquids were obtained within this temperature range. The validity of the Walden relation for this ionic liquid was also determined. This amount of experimental information, in addition to recent molecular simulation studies available in the literature give a clear picture of the structure of these binary mixtures and the influence of composition and temperature, paving the way to a technological discussion of the possible application of these mixtures as new heat transfer fluids or battery electrolytes.

The physicochemical characteristics of dissolved organic matter (DOM) strongly influence its interactions with inorganic species such as protons and trace elements in natural waters. We collected water samples at Boknis Eck, a time series station in the Baltic Sea with a low exposure to freshwater inputs, to investigate how seasonal fluctuations impact the proton binding properties of the isolated DOM. We used potentiometric titrations to assess the binding properties of solid-phase extracted DOM (SPE–DOM) over a seasonal cycle. We report and critically analyze the first NICA parameters estimates of carboxylic-like and phenolic-like sites for brackish water SPE–DOM. The total amount of functional groups (QmaxH,tot) showed no seasonal fluctuations and an average value of 136 ± 5.2 mmol·mol C–1. The average proton affinity (logKH) and binding site heterogeneity (m) showed a relatively minor variability for samples obtained between April and September, when the water remained stratified. These results contribute to a better understanding of the ion binding characteristics of DOM in natural brackish waters.

One of the current problems in engineering is the collapse of bridges that cross rivers due to the scour of their piers. This can lead to collapse and thus high costs associated with reconstruction. One way of avoiding bridge collapses is the installation of an arch-shaped superstructure that goes over the bridge, which by means of hangers lifts the deck to replace the damaged piers. A problem arises when the hangers are tight since keeping the properties of the deck of the original bridge is mandatory in order to avoid serious damages to the bridge. This paper proposes the use of algorithms with great performance in the literature, which are Black Hole and cuckoo search, to find the correct order to tight the hangers as well as the magnitude that minimizes the difference in stresses along the concrete with respect to the original bridge. Finally, the results associated with various real instances are presented according to the San Luis bridge, where the proper functioning of the Black Hole Algorithm can be observed, as opposed to cuckoo search and 4 other techniques. This implies that the use of metaheuristic techniques presents acceptable results in reasonable calculation times, validating the implementation of these techniques for this problem.