Emotion expression and cooperation under collective risks.

The difficulties associated with solving Humanity's major global challenges have increasingly led world leaders and everyday citizens to publicly adopt strong emotional responses, with either mixed or unknown impacts on others' actions. Here, we present two experiments showing that non-verbal emotional expressions in group interactions play a critical role in determining how individuals behave when contributing to public goods entailing future and uncertain returns. Participants' investments were not only shaped by emotional expressions but also enhanced by anger when compared with joy. Our results suggest that global coordination may benefit from interaction in which emotion expressions can be paramount.

Reprogramming of tumor-associated macrophages by polyaniline-coated iron oxide nanoparticles applied to treatment of breast cancer.

Breast cancer is the most commonly diagnosed type of cancer among the female population worldwide. It is a disease with a high incidence and geographic distribution that negatively impacts global public health and deleteriously affect the quality of life of cancer patients. Among the new approaches, cancer immunotherapy is the most promising trend in oncology by stimulating the host's own immune system to efficiently destroy cancer cells. Recent evidence has indicated that iron oxide nanoparticles can promote the reprograming of M2 into M1 macrophages with anti-tumor effects in the tumor microenvironment. Thus, the aim of the present work was to evaluate the ability of polyaniline-coated maghemite (Pani/γ-Fe2O3) nanoparticles to modulate human macrophages in 2D monolayers and 3D multicellular breast cancer models. It was observed that Pani/γ-Fe2O3 NPs re-educated IL-10-stimulated macrophages towards a pro-inflammatory profile, decreasing the proportion of CD163+ and increasing the CD86+ proportion in 2D models. NPs were successfully taken-up by macrophages presented in the 3D model and were also able to induce an increasing in their CD86+ proportion in triple MCTs model. Overall, our findings open new perspectives on the use of Pani/γ-Fe2O3 NPs as an immunomodulatory therapy for macrophage reprogramming towards an anti-tumor M1 phenotype, providing a new tool for breast cancer immunotherapies.

Next-generation deep learning based on simulators and synthetic data.

Deep learning (DL) is being successfully applied across multiple domains, yet these models learn in a most artificial way: they require large quantities of labeled data to grasp even simple concepts. Thus, the main bottleneck is often access to supervised data. Here, we highlight a trend in a potential solution to this challenge: synthetic data. Synthetic data are becoming accessible due to progress in rendering pipelines, generative adversarial models, and fusion models. Moreover, advancements in domain adaptation techniques help close the statistical gap between synthetic and real data. Paradoxically, this artificial solution is also likely to enable more natural learning, as seen in biological systems, including continual, multimodal, and embodied learning. Complementary to this, simulators and deep neural networks (DNNs) will also have a critical role in providing insight into the cognitive and neural functioning of biological systems. We also review the strengths of, and opportunities and novel challenges associated with, synthetic data.

Use of polypyrrole-polystyrene membranes for extracting DNA from plant tissues.

We describe the preparation of a membrane composed of polypyrrole-polystyrene (PPy-PS) and its application in DNA extraction. We adopted the electrospinning technique to prepare polystyrene (PS) membranes, which we used as substrates for incorporating polypyrrole chains through an in situ chemical procedure. As a model system, we initially investigated the use of PPy-PS membranes for the extraction of salmon sperm DNA from aqueous solutions. These studies have shown that the PPy-PS membrane has a maximum adsorption capacity of 236.0 mg of DNA per gram of PPy after 30 min of exposure to a DNA solution (100 mg/L). We incorporated the PPy-PS membranes into centrifugation columns, which we used to carry out experiments for extracting and purification of DNA from curly lettuce leaves. The protocol was initially optimized by first examining the most appropriate concentration of the three components of the lysis buffer (Tris/HCl, NaCl, and EDTA-Na). We then investigated the most adequate volumes of the concentrated surfactant solution (SDS 20%) and that used in the protein and polysaccharide precipitation step (5 M potassium acetate, pH 6.3), factors that directly influence the quality and quantity of the fraction of DNA obtained. For curly lettuce leaves, both in their mature and young stages, the yield and purity of the DNA purified using the PPy-PS membrane were comparable to those obtained using a commercial kit. In both cases, the collected DNA samples presented excellent integrity and quality. These results are suggestive that these composite membranes are competitive with the commercial kits available for the extraction and purification of DNA from plants.

Immunotherapy for cancer: effects of iron oxide nanoparticles on polarization of tumor-associated macrophages.

Cancer immunotherapy is the most promising trend in oncology, focusing on helping or activating the patient's immune system to identify and fight against cancer. In the last decade, interest in metabolic reprogramming of tumor-associated macrophages from M2-like phenotype (promoting tumor progression) to M1-like phenotypes (suppressing tumor growth) as a therapeutic strategy against cancer has increased considerably. Iron metabolism has been standing out as a target for the reprogramming of tumor-associated macrophages to M1-like phenotype with therapeutic purposes against cancer. Due to the importance of the iron levels in macrophage polarization states, iron oxide nanoparticles can be used to change the activation state of tumor-associated macrophages for a tumor suppressor phenotype and as an anti-tumor strategy.

Intrinsically conductive polymers hybrid bilayer films for the fluorescence molecular diagnosis of the Zika virus.

In 2016, the Zika virus (ZIKV) infection became a major public health problem, after the discovery that an alarming increase in the number of Brazilian newborns with microcephaly could be associated with the occurrence of this viral disease during the pregnancy of their mothers. The urgent need for simple diagnostic methods that allow rapid screening of suspected cases has stimulated the search for low-cost devices capable of detecting specific sequences of nucleic acids. The present work describes the development of nanostructured films formed by bilayers of conjugated polymers for rapid detection of the presence of Zika virus DNA, via fluorescence methods. For this, we initially deposited alternating layers of polyaniline (PANI) and polypyrrole (PPY) on the surface of polyethylene terephthalate (PET) sheets. The films obtained were then characterized by SEM, UV-Vis, ATR-FTIR, and contact angle measurements. For their use as quenchers for the diagnosis of Zika, a single DNA strand-specific for ZIKV was labeled with a fluorophore (FAM-ssDNA). We determined the time required for the saturation of the interaction between probe FAM-ssDNA and the film (180 min) and the time for the maximal hybridization between FAM-ssDNA and target DNA to occur (60 min). The detection limits were estimated as 345 pM and 278 pM for the PET/PPY-PANI and PET/PANI-PPY hybrid films, respectively. The simplicity of the procedure, coupled with the fact that a positive/negative response can be obtained in less than 60 min, suggests that the proposal of using these polymeric bilayer films is a promising methodology for the development of rapid molecular diagnostic tests.

A new biocompatible silver/polypyrrole composite with in vitro antitumor activity.

We used an in situ chemical oxidation method to prepare a new composite of silver nanoparticles (AgNPs) with polypyrrole (PPy), whose properties were optimized through a 23-factorial design of the synthesis conditions. The successful formation of the AgNPs/PPy composite was confirmed by UV-Visible and FTIR spectroscopies. Transmission electron microscopy revealed the presence of AgNPs smaller than 100 nm, dispersed into the PPy matrix. This hybrid composite exhibits a blue fluorescence emission after excitation in the ultraviolet region. In MTT assays, the AgNPs/PPy composite exhibited low cytotoxicity toward non-tumoral cell lines (fibroblast, Vero, and macrophages) and selectively inhibited the viability of HeLa cells. The AgNPs/PPy composite induces ultrastructural changes in HeLa cells that are consistent with the noticeable selectivity exhibited toward them when compared to its action against non-tumoral cell lineages. Also, the AgNPs/PPy exhibited a hemolytic activity below 14% for all blood groups tested, at concentrations up to 125 µg/mL. These results suggest that the AgNPs/PPy composite has a promising potential for use as an antitumoral agent.

DNA purification using a novel γ-Fe2O3/PEDOT hybrid nanocomposite.

We report the synthesis and characterization of a new hybrid magnetic composite formed by the enveloping of magnetic iron oxide nanoparticles (γ-NP) with chains of the conductive polymer PEDOT, and its use for the efficient separation of DNA molecules from complex biological samples, allowing the high yield separation of a pure and high-quality DNA fraction. The successful formation of the γ-NP/PEDOT composite was confirmed by Fourier transform infrared spectroscopy, scanning electron microscopy, UV visible spectroscopy (UV-Vis), and magnetic hysteresis loop measurements. The nanocomposites showed an excellent capacity of DNA adsorption (Qe âˆ¼ 248 mg/g) in a model system consisting of salmon sperm DNA. When the γ-NP/PEDOT was used in protocols to extract the DNA from complex samples, the corresponding yield was in the range of 6.4 µg (blood) and 7.3 µg (bacteria), as evaluated quality by UV-Vis, PCR analysis, and electrophoresis assays. We also established that the captured DNA does not need to be detached from the nanocomposite for use as seeding material in PCR amplification experiments. These results and the simplicity of the protocols indicate that the γ-NP/PEDOT composite is a promising DNA absorbent, being competitive with the commercially available magnetic purification kits.

Polypyrrole-coated electrospun polystyrene films as humidity sensors.

We report the preparation of flexible polystyrene/polypyrrole (PS/PPy) mats and their successful use as a resistive humidity sensor. These composite membranes were prepared by first obtaining PS films through the electrospinning technique, and then incorporating PPy chains by an in situ chemical polymerization of the pyrrole monomer. The PS fibers were homogeneously distributed, with diameters that obeyed a normal distribution with an average value of (1.04 ± 0.12) µm. The deposition of conducting PPy chains on the surface of the PS fibers was confirmed after characterizing the PS/PPy mats by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), contact angle measurements, and electrochemical impedance spectroscopy (EIS). When used as humidity sensors, the PS/PPy mats exhibited a sensor response of 128.6%, with fast response ((54.9 ± 3.5)s) and recovery times ((76.8 ± 11.1)s), and stable response under different humidity conditions over several days. These performance characteristics compare favorably to those of previous resistive humidity sensors discussed in the literature.

Heuristic thinking and altruism toward machines in people impacted by COVID-19.

Autonomous machines are poised to become pervasive, but most treat machines differently: we are willing to violate social norms and less likely to display altruism toward machines. Here, we report an unexpected effect that those impacted by COVID-19-as measured by a post-traumatic stress disorder scale-show a sharp reduction in this difference. Participants engaged in the dictator game with humans and machines and, consistent with prior research on disasters, those impacted by COVID-19 displayed more altruism to other humans. Unexpectedly, participants impacted by COVID-19 displayed equal altruism toward human and machine partners. A mediation analysis suggests that altruism toward machines was explained by an increase in heuristic thinking-reinforcing prior theory that heuristic thinking encourages people to treat machines like people-and faith in technology-perhaps reflecting long-term consequences on how we act with machines. These findings give insight, but also raise concerns, for the design of technology.

Emotion expressions shape human social norms and reputations.

The emergence of pro-social behaviors remains a key open challenge across disciplines. In this context, there is growing evidence that expressing emotions may foster human cooperation. However, it remains unclear how emotions shape individual choices and interact with other cooperation mechanisms. Here, we provide a comprehensive experimental analysis of the interplay of emotion expressions with two important mechanisms: direct and indirect reciprocity. We show that cooperation in an iterated prisoner's dilemma emerges from the combination of the opponent's initial reputation, past behaviors, and emotion expressions. Moreover, all factors influenced the social norm adopted when assessing the action of others - i.e., how their counterparts' reputations are updated - thus, reflecting longer-term consequences. We expose a new class of emotion-based social norms, where emotions are used to forgive those that defect but also punish those that cooperate. These findings emphasize the importance of emotion expressions in fostering, directly and indirectly, cooperation in society.

Kinetics and thermodynamic studies of Methyl Orange removal by polyvinylidene fluoride-PEDOT mats.

We report the preparation of poly(3,4-ethylene dioxythiophene) (PEDOT)-modified polyvinylidene fluoride electrospun fibers and their use as a novel adsorbent material for the removal of the anionic dye Methyl Orange (MO) from aqueous media. This novel adsorbent material can be used to selectively remove MO on a wide pH range (3.0-10.0), with a maximum capacity of 143.8 mg/g at pH 3.0. When used in a recirculating filtration system, the maximum absorption capacity was reached in a shorter time (20 min) than that observed for batch mode experiments (360 min). Based on the analyses of the kinetics and adsorption isotherm data, one can conclude that the predominant mechanism of interaction between the membrane and the dissolved dye molecules is electrostatic. Besides, considering the estimated values for the Gibbs energy, and entropy and enthalpy changes, it was established that the adsorption process is spontaneous and occurs in an endothermic manner. The good mechanical and environmental stability of these membranes allowed their use in at least 20 consecutive adsorption/desorption cycles, without significant loss of their characteristics. We suggest that the physical-chemical characteristics of PEDOT make these hybrid mats a promising adsorbent material for use in water remediation protocols and effluent treatment systems.

Reducing Cognitive Load and Improving Warfighter Problem Solving With Intelligent Virtual Assistants.

Recent times have seen increasing interest in conversational assistants (e.g., Amazon Alexa) designed to help users in their daily tasks. In military settings, it is critical to design assistants that are, simultaneously, helpful and able to minimize the user's cognitive load. Here, we show that embodiment plays a key role in achieving that goal. We present an experiment where participants engaged in an augmented reality version of the relatively well-known desert survival task. Participants were paired with a voice assistant, an embodied assistant, or no assistant. The assistants made suggestions verbally throughout the task, whereas the embodied assistant further used gestures and emotion to communicate with the user. Our results indicate that both assistant conditions led to higher performance over the no assistant condition, but the embodied assistant achieved this with less cognitive burden on the decision maker than the voice assistant, which is a novel contribution. We discuss implications for the design of intelligent collaborative systems for the warfighter.

The interplay of emotion expressions and strategy in promoting cooperation in the iterated prisoner's dilemma.

The iterated prisoner's dilemma has been used to study human cooperation for decades. The recent discovery of extortion and generous strategies renewed interest on the role of strategy in shaping behavior in this dilemma. But what if players could perceive each other's emotional expressions? Despite increasing evidence that emotion signals influence decision making, the effects of emotion in this dilemma have been mostly neglected. Here we show that emotion expressions moderate the effect of generous strategies, increasing or reducing cooperation according to the intention communicated by the signal; in contrast, expressions by extortionists had no effect on participants' behavior, revealing a limitation of highly competitive strategies. We provide evidence that these effects are mediated mostly by inferences about other's intentions made from strategy and emotion. These findings provide insight into the value, as well as the limits, of behavioral strategies and emotion signals for cooperation.

Metal-polymer hybrid nanomaterial for impedimetric detection of human papillomavirus in cervical specimens.

The human papillomavirus (HPV) is one of the main sexually transmitted pathogens that infect the anogenital epithelium and mucous membranes. HPV genotypes can be classified as high and low oncogenic risk, with infection by the former resulting in cervical cancer in approximately 100 % of the cases. In this work, we developed an ultrasensitive electrochemical biosensor for the detection and identification of different HPV genotypes. A nanostructured platform based on a matrix of polyaniline (PANI) containing gold nanoparticles (AuNps) was designed for the chemical immobilization of a DNA probe capable of recognizing different HPV types. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and atomic force microscopy (AFM) were used to characterize the genosensor. The impedimetric responses indicate that the proposed sensor was able to detect HPV (types 6, 11, 16, 31, 33, 45, and 58) in cervical specimens (cDNA samples). We obtained different profiles of electrochemical responses for the high and low-risk HPV genotypes. By adopting a three-dimensional quantitative analysis of impedance response variables, it was possible to identify the existence of a pattern of association for samples of high oncogenic risk, which may lead to the differential diagnosis of HPV. The biosensor demonstrated an excellent analytical performance for the detection of HPV genotypes with high sensibility and selectivity. The genosensor exhibited a linear range of response in the 1 pg µL-1 to 100 pg µL-1 range. Besides, a limit of detection (LOD) of 2.74 pg µL-1 and 7.43 pg µL-1 was obtained for HPV11 and HPV16, respectively, with regression coefficients of 99.88 % and 99.47 %. Thus, the proposed sensor may serve as a good prognostic indicator for patients infected with papillomavirus.

Spinel Cobalt Ferrite Nanoparticles for Sensing Phosphate Ions in Aqueous Media and Biological Samples.

Phosphate ions perform a variety of functions in metabolic processes and are essential for all living organisms. The determination of the concentration of phosphate ions is useful in clinical diagnosis of various diseases as an inadequate phosphate level could lead to many health problems. In the search for a cost-effective method of fast monitoring, we investigated the use of cobalt ferrite nanoparticles (CoFeNPs) in the selective recognition of phosphate ions dissolved in aqueous media and more complex samples, such as human blood serum. We prepared these NPs by a chemical coprecipitation route and subjected them to annealing at 600 °C for 1 h. The successful formation of the NPs was confirmed by Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy, and hysteresis loop measurements. The NPs exhibited a ferrimagnetic behavior, a spinel-type crystalline structure, and hexagonal shape in the nanoscale range. We demonstrated that CoFeNPs containing immobilized fluorescent-labeled single-chain DNA (ssDNA*) probes can be applied for the fast selective detection of phosphate ions dissolved in a liquid medium. We have explored the fact that phosphate groups can displace ssDNA* probes attached to the nanoparticles, therefore causing a perceptible change in the fluorescence signal of the supernatant liquid. This detection method has been tested for the sensing of phosphate ions present both in aqueous solutions and in biological samples, with excellent selectivity and a low limit of detection (∼1.75 nM).

Risk of Injury in Moral Dilemmas With Autonomous Vehicles.

As autonomous machines, such as automated vehicles (AVs) and robots, become pervasive in society, they will inevitably face moral dilemmas where they must make decisions that risk injuring humans. However, prior research has framed these dilemmas in starkly simple terms, i.e., framing decisions as life and death and neglecting the influence of risk of injury to the involved parties on the outcome. Here, we focus on this gap and present experimental work that systematically studies the effect of risk of injury on the decisions people make in these dilemmas. In four experiments, participants were asked to program their AVs to either save five pedestrians, which we refer to as the utilitarian choice, or save the driver, which we refer to as the nonutilitarian choice. The results indicate that most participants made the utilitarian choice but that this choice was moderated in important ways by perceived risk to the driver and risk to the pedestrians. As a second contribution, we demonstrate the value of formulating AV moral dilemmas in a game-theoretic framework that considers the possible influence of others' behavior. In the fourth experiment, we show that participants were more (less) likely to make the utilitarian choice, the more utilitarian (nonutilitarian) other drivers behaved; furthermore, unlike the game-theoretic prediction that decision-makers inevitably converge to nonutilitarianism, we found significant evidence of utilitarianism. We discuss theoretical implications for our understanding of human decision-making in moral dilemmas and practical guidelines for the design of autonomous machines that solve these dilemmas while, at the same time, being likely to be adopted in practice.

Cooperation with autonomous machines through culture and emotion.

As machines that act autonomously on behalf of others-e.g., robots-become integral to society, it is critical we understand the impact on human decision-making. Here we show that people readily engage in social categorization distinguishing humans ("us") from machines ("them"), which leads to reduced cooperation with machines. However, we show that a simple cultural cue-the ethnicity of the machine's virtual face-mitigated this bias for participants from two distinct cultures (Japan and United States). We further show that situational cues of affiliative intent-namely, expressions of emotion-overrode expectations of coalition alliances from social categories: When machines were from a different culture, participants showed the usual bias when competitive emotion was shown (e.g., joy following exploitation); in contrast, participants cooperated just as much with humans as machines that expressed cooperative emotion (e.g., joy following cooperation). These findings reveal a path for increasing cooperation in society through autonomous machines.

Extraction of plasmid DNA by use of a magnetic maghemite-polyaniline nanocomposite.

We describe the use of a hybrid magnetic nanocomposite (HMNC) for the extraction and purification of plasmid DNA (pDNA) from Escherichia coli aqueous solutions. The HMNC, which was synthesized via emulsion polymerization, was characterized by transmission electron microscopy, scanning electron microscopy, UV-Vis spectroscopy, Fourier transform infrared spectroscopy, dynamic light scattering and magnetic measurements. The results confirmed the incorporation of polyaniline (Pani) in its conducting form onto a core formed by the magnetic iron oxide, with the hybrid particles presenting an average size of (95 ±â€¯30) nm and a saturation magnetization of 30 emu/g. The yield, purity and quality of the pDNA purified by using the Pani HMNC were evaluated by UV-Vis spectroscopy, agarose gel electrophoresis, and Polymerase Chain Reaction (PCR), respectively. An average yield of ~6.9 µg was obtained in the DNA extraction process, with the collected material presenting a good purity (a ₳260/280 ratio in the 1.68-1.82 range) and an excellent quality, as confirmed by subsequent PCR assays. Hence, this HMNC appears as a promising material for use in pDNA purification protocols, and we suggest that this novel HMNC-based methodology can be of general interest and find widespread application in different biomedical procedures.

Human Cooperation When Acting Through Autonomous Machines.

Recent times have seen an emergence of intelligent machines that act autonomously on our behalf, such as autonomous vehicles. Despite promises of increased efficiency, it is not clear whether this paradigm shift will change how we decide when our self-interest (e.g., comfort) is pitted against the collective interest (e.g., environment). Here we show that acting through machines changes the way people solve these social dilemmas and we present experimental evidence showing that participants program their autonomous vehicles to act more cooperatively than if they were driving themselves. We show that this happens because programming causes selfish short-term rewards to become less salient, leading to considerations of broader societal goals. We also show that the programmed behavior is influenced by past experience. Finally, we report evidence that the effect generalizes beyond the domain of autonomous vehicles. We discuss implications for designing autonomous machines that contribute to a more cooperative society.