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Dynamic atomic force microscopy (AFM) modes that operate at frequencies far away from the resonance frequency of the cantilever (off-resonance tapping (ORT) modes) can provide high-resolution imaging of a wide range of sample types, including biological samples, soft polymers, and hard materials. These modes offer precise and stable control of vertical force, as well as reduced lateral force. Simultaneously, they enable mechanical property mapping of the sample. However, ORT modes have an intrinsic drawback: a low scan speed due to the limited ORT rate, generally in the low-kilohertz range. Here, we analyze how the conventional ORT control method limits the topography tracking quality and hence the imaging speed. The closed-loop controller in conventional ORT restricts the sampling rate to the ORT rate and introduces a large closed-loop delay. We present an alternative ORT control method in which the closed-loop controller samples and tracks the vertical force changes during a defined time window of the tip–sample interaction. Through this, we use multiple samples in the proximity of the maximum force for the feedback loop, rather than only one sample at the maximum force instant. This method leads to improved topography tracking at a given ORT rate and therefore enables higher scan rates while refining the mechanical property mapping.

Abstract Invasive non-native freshwater mollusks are a growing concern in South America, with 16 species already recorded in the region. Among them, Sinotaia quadrata has only been documented in Argentina, for the first time in the Punilla Valley, Córdoba (2009) and La Plata, Buenos Aires (since 2015). In this study, we report the presence of S. quadrata in two additional areas, the Río de la Plata River and a stream (unnamed) in the Paraná River basin, two of the most significant rivers in South America, located in the provinces of Buenos Aires and Entre Ríos, respectively. These new records confirm the invasive nature of this species, which has also been identified in Europe, the United States, and Africa in recent years. The findings of this study highlight the need for continued monitoring and management of invasive species in South America’s freshwater ecosystems.

Increasing integration of distributed energy resources (DER) in the electrical network has led distribution network operators to unprecedented challenges. This issue is compounded by the lack of monitoring infrastructure on the low voltage (LV) side of distribution networks at residential and utility sides. Non-intrusive load monitoring (NILM) methods provide an opportunity to add value to conventional electric measurements and to increase the observability of LV networks for the implementation of active management network techniques and intelligent control of DER. This work proposes a novel implementation of NILM methods for the identification of DER electrical signatures from aggregated measurements taken at the LV side of a distribution transformer. The implementation evaluates three machine learning algorithms such as k Nearest Neighbours (kNN), random forest and a multilayer perceptron under 100 scenarios of DER integration. A year of minutely reported values of electric current, voltage, active power, and reactive power are used to train and test the proposed model. The $F_{1}$ scores achieved of 73% and 93% for Electrical Vehicles (EV) and rooftop photovoltaic (PV) respectively and processing times below $314~\mu \text{s}$ on an Intel Core i7-8700 machine. These results confirm the relevance of the NILM method based on low frequency electric measurements from the real-time identification of DER.

El objetivo del presente estudio fue analizar los cambios producidos en el ensamble de macroinvertebrados bentónicos en respuesta a las alteraciones ambientales antropogénicas en un río de la Patagonia extrandina. Se realizaron cuatro campañas de muestreo entre marzo de 2017 y marzo de 2019, en épocas del año contrastantes, en el curso medio del río Chico (Santa Cruz). Se establecieron seis estaciones de muestreo: dos estaciones control aguas arriba de la localidad de Gobernador Gregores y cuatro aguas abajo, a distancias crecientes del centro urbano. En cada estación se midieron variables fisicoquímicas y se colectaron cuatro muestras del macrobentos utilizando una red manual tipo Surber con malla de 500 µm. Los datos de abundancia de taxones y de grupos funcionales alimentarios (GFA) se analizaron con métodos estadísticos univariados y multivariados. Se identificaron 26 taxones; los mejor representados fueron los oligoquetos, los hirudíneos, los gasterópodos y los insectos Chironomidae, Baetidae y Glossosomatidae. Las estaciones control y las más alejadas de la localidad mostraron los valores más altos de diversidad y de riqueza de taxones y GFA; los moluscos Chilinidae y Lymnaeidae junto con los insectos Baetidae, Glossosomatidae y Gripopterygidae presentaron mayor importancia. En las estaciones aguas abajo, más cercanas a la localidad, el ensamble de macroinvertebrados estuvo dominado por oligoquetos Naididae e insectos Chironomidae, presentando los valores más bajos de diversidad y riqueza de taxones y GFA. Los colectores-recolectores fueron el grupo alimentario dominante en estas estaciones, en las que el aporte de efluentes urbanos favoreció la vía detritívora y la estrategia alimentaria oportunista. Los cambios en la composición y en la estructura trófica del ensamble de macroinvertebrados constituyen información relevante para comprender las modificaciones ecológicas ante la alteración del ambiente, y son de fundamental importancia para interpretar los índices bióticos utilizados para evaluar la calidad de un cuerpo de agua.

La producción peruana de cacao representa aproximadamente el 2% de la producción mundial; con una contribución muy reconocida por la calidad y diversidad de sus sabores y aromas. De milenario origen amazónico y probada utilización de hace por lo menos 5200 años, este cultivo recién ha sido visible para el desarrollo agrario en las dos últimas décadas, cuando se le ha utilizado con relativo éxito en la sustitución de cultivos ilegales de coca ¿Y qué tanto está contribuyendo la academia a la cadena de valor del cacao? Con carácter exploratorio, se registró y analizó una muestra de 44 tesis que tenían como objeto de estudio el cacao, obtenido por sus autores en los centros de producción y parcelas de productores. La mayor parte de estas tesis (41) estuvieron destinadas a obtener títulos profesionales, dos para optar el grado de magister y uno para obtener el grado de doctorado. Estas tesis se realizaron en universidades de 13 departamentos del Perú, contando Lima con el mayor número de tesis (12). Once tesis abarcaron actividades de investigación del germoplasma para la transformación y/o la innovación del cacao, confiriéndole así valor agregado con potencial uso comercial. Estas investigaciones estuvieron relacionadas con cuatro sectores productivos con un claro potencial comercial en el mercado global de recursos genéticos. En ningún caso, las investigaciones se realizaron bajo la seguridad jurídica del sistema de acceso a recursos genéticos y participación justa y equitativa de beneficios del Protocolo de Nagoya.

In this work, we report on the integration of an atomic force microscope (AFM) into a helium ion microscope (HIM). The HIM is a powerful instrument, capable of imaging and machining of nanoscale structures with sub-nanometer resolution, while the AFM is a well-established versatile tool for multiparametric nanoscale characterization. Combining the two techniques opens the way for unprecedented in situ correlative analysis at the nanoscale. Nanomachining and analysis can be performed without contamination of the sample and environmental changes between processing steps. The practicality of the resulting tool lies in the complementarity of the two techniques. The AFM offers not only true 3D topography maps, something the HIM can only provide in an indirect way, but also allows for nanomechanical property mapping, as well as for electrical and magnetic characterization of the sample after focused ion beam materials modification with the HIM. The experimental setup is described and evaluated through a series of correlative experiments, demonstrating the feasibility of the integration.

Employing polymer cantilevers has shown to outperform using their silicon or silicon nitride analogues concerning the imaging speed of atomic force microscopy (AFM) in tapping mode (intermittent contact mode with amplitude modulation) by up to one order of magnitude. However, tips of the cantilever made out of a polymer material do not meet the requirements for tip sharpness and durability. Combining the high imaging bandwidth of polymer cantilevers with making sharp and wear-resistant tips is essential for a future adoption of polymer cantilevers in routine AFM use. In this work, we have developed a batch fabrication process to integrate silicon nitride tips with an average tip radius of 9 ± 2 nm into high-speed SU8 cantilevers. Key aspects of the process are the mechanical anchoring of a moulded silicon nitride tip and a two-step release process. The fabrication recipe can be adjusted to any photo-processable polymer cantilever.

O presente artigo visa apresentar os resultados da utilização do quiabo (Abelmoschus Esculentos) como floculante no processo de desestabilização de emulsões do tipo óleo em água, sendo estas emulsões produzidas industrialmente no setor mineiro-metalúrgico. Vários problemas ambientais podem ser gerados por emulsões óleo em água, uma vez que este tipo de emulsão reduz a oxigenação dos corpos d’água, acarretando, assim, um intenso desequilíbrio ambiental. Utilizando-se quiabos que seriam posteriormente descartados por não apresentarem mais utilidade à alimentação humana buscou-se, além do desenvolvimento da tecnologia com o uso deste reagente. A potencialidade do uso do quiabo como floculante foi confirmada através dos ensaios experimentais realizados.

A computational fluid dynamics study of the horizontal oil–water flow was performed using the Eulerian–Eulerian and mixture multiphase models in conjunction with the realizable k–ε turbulence model for the characterization of flow patterns. The experimental tests were carried out using water and mineral oil with a density of 880 kg/m3 and a viscosity of 180 cP, varying the superficial velocities of both fluids in ranges of 0.1–1.2 m/s and 0.1–0.5 m/s, respectively. The numerical model was defined under the same initial and boundary conditions as in the experiment. Moreover, the model is defined such that entering the fluids in a mixed state, the stratified pattern could form adequately with the two multiphase models. Although the Eulerian–Eulerian model, together with the geometric reconstruction scheme, allowed us to visualize the three-dimensional dispersed patterns in a very similar way to the experimental results, the mixture model did not exhibit such similarity, especially in the oil-in-water dispersions. Additionally, the Eulerian–Eulerian model was able to predict the experimental holdup values with an average error of 15.2%.

Gaining robust in situ estimates of the growth rate of marine fish larvae is essential for understanding processes controlling year-class success and developing sustainable management strategies to maintain good environmental status. We measured the growth rate of Atlantic herring (Clupea harengus) larvae in the laboratory and compared it to the activity of aminoacyl-tRNA synthetases (AARS). Larvae were reared under controlled conditions for 20 days at three temperatures (7, 12, and 17 °C) using different prey concentrations (0.1, 0.3, and 2 prey·mL−1) of the copepod Acartia tonsa. The relationship between specific growth rates (SGR) and specific AARS activities was best described by a linear function—SGR = −0.1031 + 0.0017 · spAARS, r2 = 0.71, p < 0.05—when only larvae fed ad libitum were considered regardless of the temperature. When larvae fed with low concentrations of food were included in the analysis, the relationship was SGR = −0.0332 + 0.0010 · spAARS, r2 = 0.42, p < 0.05. This latter slope was rather low compared to other studies performed in zooplankton. We suggest protein degradation during the early life stages of fish as the cause of this low slope. We also studied SGR under food deprivation and the effect on specific AARS activities. We found rather high specific AARS activities in small individuals of early stages of fish, also suggesting protein degradation. Further research about protein degradation and turnover rates is needed in order to use AARS activity as a proxy for growth rates in field-caught larvae.

Abstract The Kirkwood-Dirac quasiprobability distribution, intimately connected with the quantum correlation function of two observables measured at distinct times, is becoming increasingly relevant for fundamental physics and quantum technologies. This quasiprobability distribution can take non-positive values, and its experimental reconstruction becomes challenging when expectation values of incompatible observables are involved. Here, we use an interferometric scheme aided by an auxiliary system to reconstruct the Kirkwood-Dirac quasiprobability distribution. We experimentally demonstrate this scheme in an electron-nuclear spin system associated with a nitrogen-vacancy center in diamond. By measuring the characteristic function, we reconstruct the quasiprobability distribution of work and analyze the behavior of its first and second moments. Our results clarify the physical meaning of the work quasiprobability distribution in the context of quantum thermodynamics. Finally, we study the uncertainty of measuring the Hamiltonian of the system at two times, via the Robertson-Schrödinger uncertainty relation, for different initial states.

Abstract Microbes perform critical functions in corals, yet most knowledge is derived from the photic zone. Here, we discover two mollicutes that dominate the microbiome of the deep-sea octocoral, Callogorgia delta, and likely reside in the mesoglea. These symbionts are abundant across the host’s range, absent in the water, and appear to be rare in sediments. Unlike other mollicutes, they lack all known fermentative capabilities, including glycolysis, and can only generate energy from arginine provided by the coral host. Their genomes feature several mechanisms to interact with foreign DNA, including extensive CRISPR arrays and restriction-modification systems, which may indicate their role in symbiosis. We propose the novel family Oceanoplasmataceae which includes these symbionts and others associated with five marine invertebrate phyla. Its exceptionally broad host range suggests that the diversity of this enigmatic family remains largely undiscovered. Oceanoplasmataceae genomes are the most highly reduced among mollicutes, providing new insight into their reductive evolution and the roles of coral symbionts.

High-speed atomic force microscopy (HS-AFM) is a technique capable of revealing the dynamics of biomolecules and living organisms at the nanoscale with a remarkable temporal resolution. The phase delay in the feedback loop dictates the achievable speed of HS-AFM instruments that rely on fast nanopositioners operated predominantly in conjunction with piezoelectric actuators (PEAs). The high capacitance and high operating voltage of PEAs make them difficult to drive. The limited bandwidth of associated high-voltage piezo-amplifiers is one of the bottlenecks to higher scan speeds. In this study, we report a high-voltage, wideband voltage amplifier comprised of a separate amplification and novel voltage-follower power stage, requiring no global feedback. The reported amplifier can deliver a current over ±2 amps, offers a small-signal bandwidth of 1 MHz, and exhibits an exceptionally low phase lag, making it particularly well suited for the needs of next-generation HS-AFMs. We demonstrate its capabilities by reporting its achievable bandwidth under various PEA loads and showcasing its merit for HS-AFM by imaging tubulin protofilament dynamics at sub-second frame rates. [ABSTRACT FROM AUTHOR]

The short-term variability of plankton communities in the oceanic realm is still poorly known due to the paucity of high-resolution time-series in the open ocean. Among these few studies, there is compelling evidence of a lunar cycle of epipelagic zooplankton biomass in subtropical waters during the late winter bloom. However, there is few information about lower trophic levels and zooplankton physiological changes related to this lunar cycle. Here, we studied the short-term variability of pico-, nano-, micro-, and mesoplankton in relation to the lunar cycle in subtropical waters. Weekly sampling was carried out at four stations located north of the Canary Islands from November 2010 to June 2011. Zooplankton abundance and biomass, gut fluorescence (GF), electron transfer system (ETS), and aminoacyl-tRNA synthetase (AARS) activities were measured before, during, and after the winter vertical mixing in these waters in a wide range of size classes. Chlorophyll a, primary production, and zooplankton biomass were low, showing a rather weak late winter bloom event due to the high temperature and stratification observed. Chlorophyll, nanoplankton, diatoms, and mesozooplankton proxies for grazing (GF), respiration (ETS), and growth (AARS) varied monthly denoting a lunar pattern. Chlorophyll a, nanoplankton, diatoms, and mesozooplankton proxies for grazing and respiration peaked between 4 and 6 days after the new moon, followed by an enhancement of the mesozooplankton index of growth between 8 to 9 days after the new moon. However, mesozooplankton biomass only increased during the productive period when supposedly growth exceeded mortality. Coupled with previous results in pico-, nano-, and microplankton, we suggest that the lunar cycle governs the development of planktonic communities in the high turnover warm subtropical ocean. This study provides further evidence of the match of plankton communities with the predatory cycle exerted by diel vertical migrants, adding essential information to understand the short-term functioning of the open ocean.

BackgroundPatients undergoing surgery often experience stress and anxiety, which can increase complications and hinder recovery. Effective management of these psychological factors is key to improving outcomes. Preoperative anxiety is inversely correlated with the amount of information patients receive, but accessible, personalized support remains limited, especially in preoperative settings. Face-to-face education is often impractical due to resource constraints. Digital health (DH) interventions offer a promising alternative, enhancing patient engagement and empowerment. However, most current tools focus on providing information, overlooking the importance of personalization and psychological support. ObjectiveThis study aimed to assess the viability of a DH intervention known as the Adhera CARINAE DH Program. This program is specifically designed to offer evidence-based and personalized stress- and anxiety-management techniques. It achieves this by using a comprehensive digital ecosystem that incorporates wearable devices, mobile apps, and virtual reality technologies. The intervention program also makes use of advanced data-driven techniques to deliver tailored patient education and lifestyle support. MethodsA total of 74 patients scheduled for surgery across 4 hospitals in 3 European countries were enrolled in this study from September 2021 to March 2022. Surgeries included cardiopulmonary and coronary artery bypass surgeries, cardiac valve replacements, prostate or bladder cancer surgeries, hip and knee replacements, maxillofacial surgery, and scoliosis procedures. After assessment for eligibility, participants were randomized into 2 groups: the intervention group (n=23) received the Adhera CARINAE DH intervention in addition to standard care, while the control group (n=27) received standard care alone. Psychological metrics such as self-efficacy, self-management, and mental well-being were assessed before and after the intervention, alongside physiological markers of stress. ResultsThe intervention group demonstrated significant improvements across several psychological outcomes. For example, Visual Analogue Scale Stress at the hospital improved at admission by 5% and at hospital discharge by 11.1% and Visual Analogue Scale Pain at admission improved by 31.2%. In addition, Hospital Anxiety and Depression Scale Anxiety after surgery improved by 15.6%, and Positive and Negative Affect Scale-Negative at hospital admission improved by 17.5%. Overall, patients in the intervention study spent 17.12% less days in the hospital. Besides these individual scores, the intervention group shows more positive relationships among the psychological dimensions of self-efficacy, self-management, and mental well-being, suggesting that the CARINAE solution could have a positive effect and impact on the reduction of stress and negative emotions. ConclusionsOur results provide an important first step toward a deeper understanding of optimizing DH solutions to support patients undergoing surgery and for potential applications in remote patient monitoring and communication. Trial RegistrationClinicalTrials.gov NCT05184725; https://clinicaltrials.gov/study/NCT05184725 International Registered Report Identifier (IRRID)RR2-10.2196/38536