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Abstract Developing efficient and stable carbon nanotube (CNT) doping techniques and elucidating their chemistry is essential for their further implementation in electronic and energy devices. Here, protonic acids and lithium salts are employed as p-type inducers and stabilizers of the doped state, respectively. Leveraging the electron-withdrawing capability of protons, protonic acids can easily induce heavily p-doped states in CNTs. Anionic species from the acids attach to the positively charged CNTs to achieve charge compensation. Introducing lithium salts with bulky, charge-delocalized anions to the p-doped CNTs results in an anion replacement driven by the free energy gain. The newly formed complexes demonstrate outstanding thermal stability in air, enduring a temperature of 100 °C for over a year. The chemical hardness of the applied anion effectively explains the difference in stability of the doped CNTs, indicating that the doping process and its stabilization can be understood and controlled through complex chemistry.

Abstract The emergence of charge-neutral fermionic excitations in magnetic systems is one of the unresolved issues in recent condensed matter physics. This type of excitations has been observed in various systems, such as low-dimensional quantum spin liquids, Kondo insulators, and antiferromagnetic insulators. Here, we report the presence of a pronounced gapless spin excitation in the low-temperature antiferromagnetic state of YbCuS2 semiconductor, where trivalent ytterbium atoms form a zigzag chain structure. We confirm the presence of this gapless excitations by a combination of experimental probes, namely 63/65Cu-nuclear magnetic resonance and nuclear quadrupole resonance, as well as specific heat measurements, revealing a linear low-temperature behavior of both the nuclear spin-lattice relaxation rate 1/T 1 and the specific heat. This system provides a platform to investigate the origin of gapless excitations in spin chains and the relationship between emergent fermionic excitations and frustration.

In this study, we explored the effective capture of both cations and anions onto a single adsorbent. Acrylamide (AAm) served as the polymer backbone, onto which co-monomers sodium p-styrenesulfonate (SS) and N,N-dimethylaminopropyl acrylamide (DMAPAA) were grafted, creating ionized polymer hydrogel adsorbents. These adsorbents were engineered for the synergistic separation and recovery of heavy metal cations and anions from concentrated solutions, focusing specifically on industrially significant ions such as Ni2+-, Cu2+, Zn2+ and (Cr2O7)2-. The adsorption and desorption behaviors of the AAm terpolymer hydrogels were investigated across various pH solutions, considering the competition and concentrations of these specific metal ions. Moreover, the study delved into the effects of the internal pH environment within the hydrogel adsorbents, determining its impact on the type of metal adsorbed and the adsorption capacity. Our findings indicated that the adsorption of cations was enhanced with a higher proportion of SS relative to DMAPAA in the hydrogel. In contrast, significant anion capture occurred when the concentration of DMAPAA exceeded that of SS. However, equal ratios of SS and DMAPAA led to a noticeable reduction in the adsorption of both types of substrates, attributed to the counteractive nature of these co-monomers. To enhance the adsorption efficiency, it may be necessary to consider methods for micro-scale separation of the two types of monomers. Additionally, the adsorption capacity was observed to be directly proportional to the swelling capacity of the hydrogels. For complete desorption and separation of the cations and anions from the adsorbent, the application of concentrated NaOH solutions followed by HNO3 was found to be essential. Given the varying concentrations of cation and anion pollutants, often present in heavy metal factory effluents, it is crucial to fine-tune the ratios of DMAPAA and SS during the synthesis process. This adjustment ensures optimized efficiency in the decontamination and recovery of these significant heavy metal ions.

The preparation of stable n-type carbon nanotubes is desirable for their potential applications in molecular electronics. Here, the authors report that doping with bicyclic-ring organic superbases enables the synthesis of n-type carbon nanotubes with excellent thermal stability in air.

Objectives: The goal of this study is to examine the role of altruism and sensitivity to public shame in individuals’ willingness to pay for a COVID-19 vaccine. Study design: We apply expected utility theory to predict the role of individuals’ altruism and public shame in the willingness to pay for vaccines. Subsequently, we test the prediction by using a unique cross-sectional survey. Methods: We use online survey data collected from those aged 30–49 in Japan between June 18th and 25th, 2020 (n = 1686). The selection of respondents follows quota sampling with regard to age group, gender, and prefecture of residence. We employ an ordinary least square (OLS) model to regress respondents’ willingness to pay for a hypothetically-effective vaccine for COVID-19 on binary indicators of altruism and sensitivity to public shame, as well as socio-demographic characteristics. Results: The willingness to pay for the vaccine is higher among those with stronger altruistic concerns and sensitivity to shaming. Conclusion: Voluntary vaccinations may be inefficient, because the uptake of vaccines could be low for selfish individuals who often violate social distancing requirements. To improve the efficiency of vaccine uptake, some interventions, such as nudges and a vaccine passport, may be needed.

Schistosome helminths infect over 200 million people across 78 countries and are responsible for nearly 300,000 deaths annually. However, our understanding of basic genetic pathways crucial for schistosome development is limited. The sex determining region Y-box 2 (Sox2) protein is a Sox B type transcriptional activator that is expressed prior to blastulation in mammals and is necessary for embryogenesis. Sox expression is associated with pluripotency and stem cells, neuronal differentiation, gut development, and cancer. Schistosomes express a Sox-like gene expressed in the schistosomula after infecting a mammalian host when schistosomes have about 900 cells. Here, we characterized and named this Sox-like gene SmSOXS1. SmSoxS1 protein is a developmentally regulated activator that localizes to the anterior and posterior ends of the schistosomula and binds to Sox-specific DNA elements. In addition to SmSoxS1, we have also identified an additional six Sox genes in schistosomes, two Sox B, one SoxC, and three Sox genes that may establish a flatworm-specific class of Sox genes with planarians. These data identify novel Sox genes in schistosomes to expand the potential functional roles for Sox2 and may provide interesting insights into early multicellular development of flatworms.

Properties of perovskite oxides can be changed by manipulating anion-vacancy order patterns, but they are difficult to control. Here the authors show strain-induced creation and switching of anion vacancies in perovskite films in which the direction or periodicity of anion-vacancy planes is altered depending on the substrate employed.

BackgroundPolymerase chain reaction (PCR) is an important means by which to study the urine microbiome and is emerging as possible alternative to urine cultures to identify pathogens that cause urinary tract infection (UTI). However, PCR is limited by its inability to differentiate DNA originating from viable, metabolically active versus non-viable, inactive bacteria. This drawback has led to concerns that urobiome studies and PCR-based diagnosis of UTI are confounded by the presence of relic DNA from non-viable bacteria in urine. Propidium monoazide (PMA) dye can penetrate cells with compromised cell membranes and covalently bind to DNA, rendering it inaccessible to amplification by PCR. Although PMA has been shown to differentiate between non-viable and viable bacteria in various settings, its effectiveness in urine has not been previously studied. We sought to investigate the ability of PMA to differentiate between viable and non-viable bacteria in urine.MethodsVarying amounts of viable or non-viable uropathogenic E. coli (UTI89) or buffer control were titrated with mouse urine. The samples were centrifuged to collect urine sediment or not centrifuged. Urine samples were incubated with PMA and DNA cross-linked using blue LED light. DNA was isolated and uidA gene-specific PCR was performed. For in vivo studies, mice were inoculated with UTI89, followed by ciprofloxacin treatment or no treatment. After the completion of ciprofloxacin treatment, an aliquot of urine was plated on non-selective LB agar and another aliquot was treated with PMA and subjected to uidA-specific PCR.ResultsPMA’s efficiency in excluding DNA signal from non-viable bacteria was significantly higher in bacterial samples in phosphate-buffered saline (PBS, dCT=13.69) versus bacterial samples in unspun urine (dCT=1.58). This discrepancy was diminished by spinning down urine-based bacterial samples to collect sediment and resuspending it in PBS prior to PMA treatment. In 3 of 5 replicate groups of UTI89-infected mice, no bacteria grew in culture; however, there was PCR amplification of E. coli after PMA treatment in 2 of those 3 groups.ConclusionWe have successfully developed PMA-based PCR methods for amplifying DNA from live bacteria in urine. Our results suggest that non-PMA bound DNA from live bacteria can be present in urine, even after antibiotic treatment. This indicates that viable but non-culturable E. coli can be present following treatment of UTI, and may explain why some patients have persistent symptoms but negative urine cultures following UTI treatment.

Urogenital schistosomiasis remains a major public health concern worldwide. In response to egg deposition, the host bladder undergoes gross and molecular morphological changes relevant for disease manifestation. However, limited mechanistic studies to date imply that the molecular mechanisms underlying pathology are not well-defined. We leveraged a mouse model of urogenital schistosomiasis to perform for the first time, proteome profiling of the early molecular events that occur in the bladder after exposure to S. haematobium eggs, and to elucidate the protein pathways involved in urogenital schistosomiasis-induced pathology. Purified S. haematobium eggs or control vehicle were microinjected into the bladder walls of mice. Mice were sacrificed seven days post-injection and bladder proteins isolated and processed for proteome profiling using mass spectrometry. We demonstrate that biological processes including carcinogenesis, immune and inflammatory responses, increased protein translation or turnover, oxidative stress responses, reduced cell adhesion and epithelial barrier integrity, and increased glucose metabolism were significantly enriched in S. haematobium infection. S. haematobium egg deposition in the bladder results in significant changes in proteins and pathways that play a role in pathology. Our findings highlight the potential bladder protein indicators for host-parasite interplay and provide new insights into the complex dynamics of pathology and characteristic bladder tissue changes in urogenital schistosomiasis. The findings will be relevant for development of improved interventions for disease control. Author summary The molecular mechanisms underlying the urinary and genital pathology from urogenital schistosomiasis have not been well-defined. This has mainly been due to limited mechanistic studies and the lack of a suitable animal model for S. haematobium infection. We leveraged a mouse model of urogenital schistosomiasis, along with proteomics analysis, to determine the early molecular events that occur in the bladder after exposure to S. haematobium eggs, and to define protein pathways that may be involved in morbidity from urogenital schistosomiasis infection. Our results show that S. haematobium egg deposition in the bladder results in significant changes in proteins and pathways that play a role in pathology. Biological processes including carcinogenesis, immune and inflammatory responses, increased protein translation or turnover, oxidative stress responses, reduced cell adhesion and epithelial barrier integrity, and increased glucose metabolism are significantly enriched in S. haematobium infection. Our findings highlight important protein indicators of host-parasite interactions in the bladder and their association with tissue changes in urogenital schistosomiasis. The findings presented here will be relevant for development of improved interventions for disease control, and contribute to realizing the 2021–2030 NTD goals by demonstrating evidence on the early events that occur during schistosome infection.

Abstract To achieve quantitative palpation in vivo, we developed a catheter-type tactile sensor composed of a polyvinylidene fluoride film for minimally invasive surgery. We evaluated the fundamental performance of the prototype sensor by a weight-drop test. We also measured the output of the prototype sensor as it was inserted into a blood vessel model with shapes mimicking lesions. The ø2-mm sensor passed easily into the blood vessel model with lesion-like shapes. Sensor outputs corresponded to the shape of the inner wall of the blood vessel model, making it possible to determine the position of a protrusion and the convexity interval of a rough surface by filtering and frequency analysis of the output.

BackgroundTo control the COVID-19 pandemic, it is essential to trace and contain infection chains; for this reason, policymakers have endorsed the usage of contact tracing apps. To date, over 50 countries have released such apps officially or semiofficially, but those that rely on citizens’ voluntary uptake suffer from low adoption rates, reducing their effectiveness. Early studies suggest that the low uptake is driven by citizens’ concerns about security and privacy, as well as low perceptions of infection risk and benefits from the usage. However, these do not explore important generational differences in uptake decision or the association between individuals’ prosociality and uptake. ObjectiveThe objective of our study was to examine the role of individuals’ prosociality and other factors discussed in the literature, such as perceived risk and trust in government, in encouraging the usage of contact tracing apps in Japan. We paid particular attention to generational differences. MethodsA web-based survey was conducted in Japan 6 months after the release of a government-sponsored contact tracing app. Participants were recruited from individuals aged between 20 and 69 years. Exploratory factor analyses were conducted to measure prosociality, risk perception, and trust in government. Logistic regression was used to examine the association between these factors and uptake. ResultsThere was a total of 7084 respondents, and observations from 5402 respondents were used for analysis, of which 791 respondents (14.6%) had ever used the app. Two factors of prosociality were retained: agreeableness and attachment to the community. Full-sample analysis demonstrated app uptake was determined by agreeableness, attachment to the community, concern about health risks, concern about social risks, and trust in the national government; however, important differences existed. The uptake decision of respondents aged between 20 and 39 years was attributed to their attachment to the community (odds ratio [OR] 1.28, 95% CI 1.11-1.48). Agreeable personality (OR 1.18, 95% CI 1.02-1.35), concern about social risk (OR 1.17, 95% CI 1.02-1.35), and trust in national government (OR 1.16, 95% CI 1.05-1.28) were key determinants for those aged between 40 and 59 years. For those aged over 60 years, concerns about health risks determined the uptake decision (OR 1.49, 95% CI 1.24-1.80). ConclusionsPolicymakers should implement different interventions for each generation to increase the adoption rate of contact tracing apps. It may be effective to inform older adults about the health benefits of the apps. For middle-age adults, it is important to mitigate concerns about security and privacy issues, and for younger generations, it is necessary to boost their attachment to their community by utilizing social media and other web-based network tools.

One solution supporting a healthy mental state for humans is controlling the environment with ambient intelligence technology. We are developing a mental support system for healthy people that automatically changes environmental conditions, such as sound volume and light color, depending on the user’s mental state, which is monitored according to physiological signals such as sympathetic nerve activity. In our previous basic study under laboratory-controlled conditions, the system was applied to improve the user’s concentration level as they performed calculation tasks. Results indicated that the system improved the task performance, but individual variations existed, with some users improving greatly but others much less. For the future practical application of the system, determining the causes of the variation in efficacy is important. Considering that the brain structure and activity differ according to an individual’s personality, we investigated the relationship between the user’s personality and task performance with our system’s support. The results showed a clear correlation between the extraversion score and task performance. Our study presents an example where the system’s efficacy is sensitive to the user’s personality and indicates the importance of considering the user’s personality when designing a mental support system based on ambient intelligence.

Introduction: Leg spasticity in degenerative compression myelopathy causes impairment of fast and rapid repetitive movements, which tends to appear despite the disproportionate paucity of clinical weakness. As clinically useful measures used to quantify the slowness of voluntary leg movements in this pathological condition, we compared the foot tapping test (FTT) with the simple walking test, which is now considered the gold standard in this field. Methods: We compared the FTT with the simple walking test, the grip-and-release test, and the functional scales of Nurick and the Japanese Orthopedic Association (JOA) in 77 patients with cervical compression myelopathy and 56 age-matched healthy subjects. The FTT was conducted on both sides separately, and the subject, while being seated on a chair, moved his/her toes up and down repeatedly to tap the floor as fast and as vigorously as possible for 10 sec with his/her heels planted on the floor. Results: The number of 10-sec foot tapping in the patient group significantly correlated with the Nurick grades (r = −0.566; P < 0.0001), the JOA scores (r = 0.520; P < 0.0001), and the grip-and-release rates (r = 0.609; P < 0.0001). It also significantly correlated with the 30-m walking time (r = −0.507; P < 0.0001) and the number of steps taken (r = −0.494; P < 0.0001). Assessments of wheelchair-dependent patients and side-to-side comparison, in which the simple walking test plays no role, revealed significantly fewer FTT taps in wheelchair-bound patients than in the ambulatory patients and a significant trend for cervical compression myelopathy to dominantly affect the upper and lower limbs on the same side. Conclusions: This study contributes to the reassessment of the currently underutilized FTT as part of a routine neurologic examination of degenerative compression myelopathy.

This debate examines the impact of infodemics – an over-abundance of information – on social distancing during the COVID-19 pandemic. Because of its external effects, social distancing behavior (SDB) shares fundamental properties with public goods, whose potential for undersupply has been examined extensively in the social sciences. Although the negative effects of infodemics have been emphasized by governments and international organizations, theoretical models suggest that infodemics may work as a mitigation mechanism. That is, infodemics may enhance people’s SDBs. Based on original survey data, we show that media exposure can positively increase SDB. We conclude by discussing two public health implications. First, the media plays an important role in motivating SDB. Second, even if infodemics can increase SDB, we must be wary of their ability to pose other, non-negligible dangers.

[This corrects the article DOI: 10.1371/journal.pone.0098302.].

Driver cognitive distraction is a critical factor in road safety, and its evaluation, especially under real conditions, presents challenges to researchers and engineers. In this study, we considered mental workload from a secondary task as a potential source of cognitive distraction and aimed to estimate the increased cognitive load on the driver with a four-channel near-infrared spectroscopy (NIRS) device by introducing a machine-learning method for hemodynamic data. To produce added cognitive workload in a driver beyond just driving, two levels of an auditory presentation n-back task were used. A total of 60 experimental data sets from the NIRS device during two driving tasks were obtained and analyzed by machine-learning algorithms. We used two techniques to prevent overfitting of the classification models: (1) k-fold cross-validation and principal-component analysis, and (2) retaining 25% of the data (testing data) for testing of the model after classification. Six types of classifier were trained and tested: decision tree, discriminant analysis, logistic regression, the support vector machine, the nearest neighbor classifier, and the ensemble classifier. Cognitive workload levels were well classified from the NIRS data in the cases of subject-dependent classification (the accuracy of classification increased from 81.30 to 95.40%, and the accuracy of prediction of the testing data was 82.18 to 96.08%), subject 26 independent classification (the accuracy of classification increased from 84.90 to 89.50%, and the accuracy of prediction of the testing data increased from 84.08 to 89.91%), and channel-independent classification (classification 82.90%, prediction 82.74%). NIRS data in conjunction with an artificial intelligence method can therefore be used to classify mental workload as a source of potential cognitive distraction in real time under naturalistic conditions; this information may be utilized in driver assistance systems to prevent road accidents.

Infection with Schistosoma haematobium leads to urogenital schistosomiasis, which has been correlated with the occurrence of bladder cancer. However, mechanisms responsible for this association have not yet been clearly identified. In this short review, we provide an update, highlighting the most recent studies on schistosome-associated bladder cancer, including those that focus on identifying changes in host biology during S. haematobium infection, as well as studies for the identification of potentially pro-carcinogenic parasite molecules, and we offer a discussion on some possible mechanisms driving schistosomal bladder cancer.

Schistosomiasis is a debilitating disease that affects over 240 million people worldwide and is considered the most important neglected tropical disease following malaria. Free-swimming freshwater cercariae, one of the six morphologically distinct schistosome life stages, infect humans by directly penetrating through the skin. Cercariae identify and seek the host by sensing chemicals released from human skin. When they reach the host, they burrow into the skin with the help of proteases and other contents released from their acetabular glands and transform into schistosomula, the subsequent larval worm stage upon skin infection. Relative to host invasion, studies have primarily focused on the nature of the acetabular gland secretions, immune response of the host upon exposure to cercariae, and cercaria-schistosomulum transformation methods. However, the molecular signaling pathways involved from host-seeking through the decision to penetrate skin are not well understood. We recently observed that heat shock factor 1 (Hsf1) is localized to the acetabular glands of infectious schistosome cercariae, prompting us to investigate a potential role for heat shock proteins (HSPs) in cercarial invasion. In this study, we report that cercarial invasion behavior, similar to the behavior of cercariae exposed to human skin lipid, is regulated through an Hsp70-dependent process, which we show by using chemical agents that target Hsp70. The observation that biologically active protein activity modulators can elicit a direct and clear behavioral change in parasitic schistosome larvae is itself interesting and has not been previously observed. This finding suggests a novel role for Hsp70 to act as a switch in the cercaria-schistosomulum transformation, and it allows us to begin elucidating the pathways associated with cercarial host invasion. In addition, because the Hsp70 protein and its structure/function is highly conserved, the model that Hsp70 acts as a behavior transitional switch could be relevant to other parasites that also undergo an invasion process and can apply more broadly to other organisms during morphological transitions. Finally, it points to a new function for HSPs in parasite/host interactions.

Schistosomiasis is a chronically debilitating disease caused by parasitic worms of the genus Schistosoma, and it is a global problem affecting over 240 million people. Little is known about the regulatory proteins and mechanisms that control schistosome host invasion, gene expression, and development. Schistosome larvae, cercariae, are transiently free-swimming organisms and infectious to man. Cercariae penetrate human host skin directly using proteases that degrade skin connective tissue. These proteases are secreted from anucleate acetabular glands that contain many proteins, including heat shock proteins. Heat shock transcription factors are strongly conserved activators that play crucial roles in the maintenance of cell homeostasis by transcriptionally regulating heat shock protein expression. In this study, we clone and characterize the schistosome Heat shock factor 1 gene (SmHSF1). We verify its ability to activate transcription using a modified yeast one-hybrid system, and we show that it can bind to the heat shock binding element (HSE) consensus DNA sequence. Our quantitative RT-PCR analysis shows that SmHSF1 is expressed throughout several life-cycle stages from sporocyst to adult worm. Interestingly, using immunohistochemistry, a polyclonal antibody raised against an Hsf1-peptide demonstrates a novel localization for this conserved, stress-modulating activator. Our analysis suggests that schistosome Heat shock factor 1 may be localized to the acetabular glands of infective cercariae.

Schistosome worms of the genus Schistosoma are the causative agents of schistosomiasis, a devastating parasitic disease affecting more than 240 million people worldwide. Schistosomes have complex life cycles, and have been challenging to manipulate genetically due to the dearth of molecular tools. Although the use of gene overexpression, gene knockouts or knockdowns are straight-forward genetic tools applied in many model systems, gene misexpression and genetic manipulation of schistosome genes in vivo has been exceptionally challenging, and plasmid based transfection inducing gene expression is limited. We recently reported the use of polyethyleneimine (PEI) as a simple and effective method for schistosome transfection and gene expression. Here, we use PEI-mediated schistosome plasmid transgenesis to define and compare gene expression profiles from endogenous and nonendogenous promoters in the schistosomula stage of schistosomes that are potentially useful to misexpress (underexpress or overexpress) gene product levels. In addition, we overexpress schistosome genes in vivo using a strong promoter and show plasmid-based misregulation of genes in schistosomes, producing a clear and distinct phenotype--death. These data focus on the schistosomula stage, but they foreshadow strong potential for genetic characterization of schistosome molecular pathways, and potential for use in overexpression screens and drug resistance studies in schistosomes using plasmid-based gene expression.