Water-responsive supercontractile polymer films for bioelectronic interfaces.

Connecting different electronic devices is usually straightforward because they have paired, standardized interfaces, in which the shapes and sizes match each other perfectly. Tissue-electronics interfaces, however, cannot be standardized, because tissues are soft1-3 and have arbitrary shapes and sizes4-6. Shape-adaptive wrapping and covering around irregularly sized and shaped objects have been achieved using heat-shrink films because they can contract largely and rapidly when heated7. However, these materials are unsuitable for biological applications because they are usually much harder than tissues and contract at temperatures higher than 90 °C (refs. 8,9). Therefore, it is challenging to prepare stimuli-responsive films with large and rapid contractions for which the stimuli and mechanical properties are compatible with vulnerable tissues and electronic integration processes. Here, inspired by spider silk10-12, we designed water-responsive supercontractile polymer films composed of poly(ethylene oxide) and poly(ethylene glycol)-α-cyclodextrin inclusion complex, which are initially dry, flexible and stable under ambient conditions, contract by more than 50% of their original length within seconds (about 30% per second) after wetting and become soft (about 100 kPa) and stretchable (around 600%) hydrogel thin films thereafter. This supercontraction is attributed to the aligned microporous hierarchical structures of the films, which also facilitate electronic integration. We used this film to fabricate shape-adaptive electrode arrays that simplify the implantation procedure through supercontraction and conformally wrap around nerves, muscles and hearts of different sizes when wetted for in vivo nerve stimulation and electrophysiological signal recording. This study demonstrates that this water-responsive material can play an important part in shaping the next-generation tissue-electronics interfaces as well as broadening the biomedical application of shape-adaptive materials.

General and Scalable Synthesis of Mesoporous 2D MZrO2 (M = Co, Mn, Ni, Cu, Fe) Nanocatalysts by Amorphous-to-Crystalline Transformation.

In modern heterogeneous catalysis, it remains highly challenging to create stable, low-cost, mesoporous 2D photo-/electro-catalysts that carry atomically dispersed active sites. In this work, a general shape-preserving amorphous-to-crystalline transformation (ACT) strategy is developed to dope various transition metal (TM) heteroatoms in ZrO2, which enabled the scalable synthesis of TMs/oxide with a mesoporous 2D structure and rich defects. During the ACT process, the amorphous MZrO2 nanoparticles (M = Fe, Ni, Cu, Co, Mn) are deposited within a confined space created by the NaCl template, and they transform to crystalline 2D ACT-MZrO2 nanosheets in a shape-preserving manner. The interconnected crystalline ACT-MZrO2 nanoparticles thus inherit the same structure as the original MZrO2 precursor. Owing to its rich active sites on the surface and abundant oxygen vacancies (OVs), ACT-CoZrO2 gives superior performance in catalyzing the CO2-to-syngas conversion as demonstrated by experiments and theoretical calculations. The ACT chemistry opens a general route for the scalable synthesis of advanced catalysts with precise microstructure by reconciliating the control of crystalline morphologies and the dispersion of heteroatoms.

Characterization of Complete Mitochondrial Genome and Phylogenetic Analysis of a Nocturnal Wasps-Provespa barthelemyi (Hymenoptera: Vespidae).

Genus Provespa contains nocturnal wasps mainly found in the southeastern region of Asia. There are no complete genome resources available of this genus, which hinders the study of its phylogenetic evolution and the origin of nocturnal behavior in the Vespidae family. Through high-throughput sequencing, we obtained the mitochondrial genome of Provespa barthelemyi (Hymenoptera: Vespidae), which is 17,721 base pairs in length and contains 13 protein-coding genes (PCGs), 22 tRNAs, and two rRNAs. We identified four gene rearrangement events of P. barthelemyi that frequently occur in the Vespidae family. We used Maximum Likelihood (ML) methodologies to construct a phylogenetic tree based on the sequenced mitochondrial genome and the available data of reported species belonging to Vespinae. Our findings confirmed the monophyly of Vespinae. Our study reports the first complete mitochondrial genome of Provespa and compares its characteristics with other mitochondrial genomes in the family Vespidae. This research should shed light on the phylogenetic relationships and ecological characteristics of the Vespidae family.

Natural mycotoxin contamination in dog food: A review on toxicity and detoxification methods.

Nowadays, the companion animals (dogs or other pets) are considered as members of the family and have established strong emotional relationships with their owners. Dogs are long lived compared to food animals, so safety, adequacy, and efficacy of dog food is of great importance for their health. Cereals, cereal by-products as well as feedstuffs of plant origin are commonly employed food resources in dry food, yet are potential ingredients for mycotoxins contamination, so dogs are theoretically more vulnerable to exposure when consumed daily. Aflatoxins (AF), deoxynivalenol (DON), fumonisins (FUM), ochratoxin A (OTA), and zearalenone (ZEA) are the most frequent mycotoxins that might present in dog food and cause toxicity on the growth and metabolism of dogs. An understanding of toxicological effects and detoxification methods (physical, chemical, or biological approaches) of mycotoxins will help to improve commercial ped food quality, reduce harm and minimize exposure to dogs. Herein, we outline a description of mycotoxins detected in dog food, toxicity and clinical findings in dogs, as well as methods applied in mycotoxins detoxification. This review aims to provide a reference for future studies involved in the evaluation of the risk, preventative strategies, and clear criteria of mycotoxins for minimizing exposure, reducing harm, and preventing mycotoxicosis in dog.

Multienzymatic disintegration of DNA-scaffolded magnetic nanoparticle assembly for malarial mitochondrial DNA detection.

Early diagnosis of malaria can prevent the spread of disease and save lives, which, however, remains challenging in remote and less developed regions. Here we report a portable and low-cost optomagnetic biosensor for rapid amplification and detection of malarial mitochondrial DNA. Bioresponsive magnetic nanoparticle assemblies are constructed by using nucleic acid scaffolds containing endonucleolytic DNAzymes and their substrates, which can be activated by the presence of target DNA and self-disintegrated to release magnetic nanoparticles for optomagnetic quantification. Specifically, target molecules can induce padlock probe ligation and subsequent one-pot homogeneous cascade reactions consisting of nicking-enhanced rolling circle amplification, DNAzyme-assisted nucleic acid recycling, and strand-displacement-driven disintegration of the magnetic assembly. With an optimized magnetic actuation process for reaction acceleration, a detection limit of 1 fM can be achieved by the proposed biosensor with a total assay time of ca. 90 min and a dynamic detection range spanning 3 orders of magnitude. The robustness of the system was validated by testing target molecules spiked in 5% serum samples. Clinical sample validation was conducted by testing malaria-positive clinical blood specimens, obtaining quantitative results concordant with qPCR measurements.

Human myiasis in Sub-Saharan Africa: A systematic review.

BACKGROUND: Human myiasis is a parasitic dipteran fly infestation that infects humans and vertebrates worldwide. However, the disease is endemic in Sub-Saharan Africa and Latin America. In Sub-Saharan Africa, it is under-reported and therefore its prevalence is unknown. This systematic review aims to elucidate the prevalence of human myiasis, factors that influence the infection, and myiasis-causing fly species in SSA. The review also dwelled on the common myiasis types and treatment methods of human myiasis. METHODS: Here, we collect cases of human myiasis in Sub-Saharan Africa based on literature retrieved from PubMed, Google Scholar and Science Direct from 1959 to 2022. A total of 75 articles and 157 cases were included in the study. The recommendations of PRISMA 2020 were used for the realization of this systematic review. RESULTS: In total, 157 cases of human myiasis in SSA were reviewed. Eleven fly species (Cordylobia anthropophaga, Cordylobia rodhaini, Dermatobia hominis, Lucilia cuprina, Lucilia sericata, Oestrus ovis, Sarcophaga spp., Sarcophaga nodosa, Chrysomya megacephala, Chrysomya chloropyga and Clogmia albipuntum) were found to cause human myiasis in SSA. Cordylobia anthropophaga was the most prevalent myiasis-causing species of the reported cases (n = 104, 66.2%). More than half of the reported cases were from travelers returning from SSA (n = 122, 77.7%). Cutaneous myiasis was the most common clinical presentation of the disease (n = 86, 54.7%). Females were more infected (n = 78, 49.6%) than males, and there was a higher infestation in adults than young children. CONCLUSION: The findings of this study reveals that international travelers to Sub-Saharan Africa were mostly infested therefore, we recommend that both international travelers and natives of SSA be enlightened by public health officers about the disease and its risk factors at entry points in SSA and the community level respectively. Clinicians in Sub-Saharan Africa often misdiagnose the disease and most of them lack the expertise to properly identify larvae, so we recommend the extensive use of molecular identification methods instead.

An Antidehydration Hydrogel Based on Zwitterionic Oligomers for Bioelectronic Interfacing.

Hydrogels are ideal interfacing materials for on-skin healthcare devices, yet their susceptibility to dehydration hinders their practical use. While incorporating hygroscopic metal salts can prevent dehydration and maintain ionic conductivity, concerns arise regarding metal toxicity due to the passage of small ions through the skin barrier. Herein, an antidehydration hydrogel enabled by the incorporation of zwitterionic oligomers into its network is reported. This hydrogel exhibits exceptional water retention properties, maintaining ≈88% of its weight at 40% relative humidity, 25 °C for 50 days and about 84% after being heated at 50 °C for 3 h. Crucially, the molecular weight design of the embedded oligomers prevents their penetration into the epidermis, as evidenced by experimental and molecular simulation results. The hydrogel allows stable signal acquisition in electrophysiological monitoring of humans and plants under low-humidity conditions. This research provides a promising strategy for the development of epidermis-safe and biocompatible antidehydration hydrogel interfaces for on-skin devices.

Identification of Forensically Important Carrion Beetles (Coleoptera: Staphilinidae) in China Based on COI and COII.

Unambiguous and speedy necrophagous insect species identification is common task in forensic entomological study. Carrion beetles (Staphilinidae: Silphinae) belong to a small group of Coleoptera with less than 200 species worldwide. Some species are commonly found on dead body during forensic entomological investigation. Despite some species are hard to be categorized morphologically, present DNA-based technologies offer a potential identification strategy. Here, 37 carrion beetle specimens were collected from 15 locations throughout Chinese mainland. The cytochrome oxidase subunit I (COI) and II (COII) genes among all specimens were successfully sequenced, which provided reliable markers for precise identification. Mostly, the interspecific distance could clarify the capability of these genes for identifying included carrion beetle species. Exceptions existed between close species in Nicrophorus genus (Fabricius 1775). The sequenced gene's phylogenetic analysis revealed that all carrion beetle specimens were correctly classified into eight genera, and most have relatively high supporting values (>90%). Our data gives genetic diversity and a reference for global forensically important carrion beetle species identification, as well as a conductive significance for future application of Chinese carrion beetles in forensic entomology.

Dual-Conductive and Stiffness-Morphing Microneedle Patch Enables Continuous In Planta Monitoring of Electrophysiological Signal and Ion Fluctuation.

The use of conductive microneedles presents a promising solution for achieving high-fidelity electrophysiological recordings with minimal impact on the interfaced tissue. However, a conventional metal-based microneedle suffers from high electrochemical impedance and mechanical mismatch. In this paper, we report a dual-conductive (i.e., both ionic and electronic conductive) and stiffness-morphing microneedle patch (DSMNP) for high-fidelity electrophysiological recordings with reduced tissue damage. The polymeric network of the DSMNP facilitates electrolyte absorption and therefore allows the transition of stiffness from 6.82 to 0.5139 N m-1. Furthermore, the nanoporous conductive polymer increases the specific electrochemical surface area after tissue penetration, resulting in an ultralow specific impedance of 893.13 Ω mm2 at 100 Hz. DSMNPs detect variation potential and action potential in real time and cation fluctuations in plants in response to environmental stimuli. After swelling, DSMNPs mechanically "lock" into biological tissues and prevent motion artifact by providing a stable interface. These results demonstrate the potential of DSMNPs for various applications in the field of plant physiology research and smart agriculture.

A Leaf-Patchable Reflectance Meter for In Situ Continuous Monitoring of Chlorophyll Content.

Plant wearable sensors facilitate the real-time monitoring of plant physiological status. In situ monitoring of the plant chlorophyll content over days can provide valuable information on the photosynthetic capacity, nitrogen content, and general plant health. However, it cannot be achieved by current chlorophyll measuring methods. Here, a miniaturized and plant-wearable chlorophyll meter for rapid, non-destructive, in situ, and long-term chlorophyll monitoring is developed. The reflectance-based chlorophyll sensor with 1.5 mm thickness and 0.2 g weight (1000 times lighter than the commercial chlorophyll meter), includes a light emitting diode (LED) and two symmetric photodetectors (PDs) on a flexible substrate, and is patched onto the leaf upper epidermis with a conformal light guiding layer. A chlorophyll content index (CCI) calculated based on the sensor shows a better linear relationship with the leaf chlorophyll content (r2 > 0.9) than the traditional chlorophyll meter. This meter can wirelessly communicate with a smartphone to monitor the leaf chlorophyll change under various stresses and indicate the unhealthy status of plants for long-term application of plants under various stresses earlier than chlorophyll meter and naked-eye observation. This wearable chlorophyll sensing patch is promising in smart and precision agriculture.

Removal of pharmaceutical and personal care products (PPCPs) by MOF-derived carbons: A review.

Nowadays, the increasing demand for pharmaceuticals and personal care products (PPCPs) has resulted in the uncontrolled release of large amounts of PPCPs into the environment, which poses a great challenge to the existing wastewater treatment technologies. Therefore, novel materials for efficient treatment of PPCPs need to be developed urgently. MOF-derived carbons (MDCs), have many advantages such as high mechanical strength, excellent water stability, large specific surface area, excellent electron transfer capability, and environmental friendliness. These advantages give MDCs an excellent ability to remove PPCPs. In this review, the effects of different substances on the properties and functions of MDCs are discussed. In addition, representative applications of MDCs and composites for the removal of PPCPs in the field of adsorption and catalysis are summarized. Finally, the future challenges of MDCs and composites are foreseen.

Grassland health assessment based on indicators monitored by UAVs: a case study at a household scale.

Grassland health assessment (GHA) is a bridge of study and management of grassland ecosystem. However, there is no standardized quantitative indicators and long-term monitor methods for GHA at a large scale, which may hinder theoretical study and practical application of GHA. In this study, along with previous concept and practices (i.e., CVOR, the integrated indexes of condition, vigor, organization and resilience), we proposed an assessment system based on the indicators monitored by unmanned aerial vehicles (UAVs)-UAVCVOR, and tested the feasibility of UAVCVOR at typical household pastures on the Qinghai-Tibetan Plateau, China. Our findings show that: (1) the key indicators of GHA could be measured directly or represented by the relative counterpart indicators that monitored by UAVs, (2) there was a significantly linear relationship between CVOR estimated by field- and UAV-based data, and (3) the CVOR decreased along with the increasing grazing intensity nonlinearly, and there are similar tendencies of CVOR that estimated by the two methods. These findings suggest that UAVs is suitable for GHA efficiently and correctly, which will be useful for the protection and sustainable management of grasslands.

UAV Assisted Livestock Distribution Monitoring and Quantification: A Low-Cost and High-Precision Solution.

Grazing management is one of the most widely practiced land uses globally. Quantifying the spatiotemporal distribution of livestock is critical for effective management of livestock-grassland grazing ecosystem. However, to date, there are few convincing solutions for livestock dynamic monitor and key parameters quantification under actual grazing situations. In this study, we proposed a pragmatic method for quantifying the grazing density (GD) and herding proximities (HP) based on unmanned aerial vehicles (UAVs). We further tested its feasibility at three typical household pastures on the Qinghai-Tibetan Plateau, China. We found that: (1) yak herds grazing followed a rotational grazing pattern spontaneously within the pastures, (2) Dispersion Index of yak herds varied as an M-shaped curve within one day, and it was the lowest in July and August, and (3) the average distance between the yak herd and the campsites in the cold season was significantly shorter than that in the warm season. In this study, we developed a method to characterize the dynamic GD and HP of yak herds precisely and effectively. This method is ideal for studying animal behavior and determining the correlation between the distribution of pastoral livestock and resource usability, delivering critical information for the development of grassland ecosystem and the implementation of sustainable grassland management.

Simulation of anaerobic co-digestion of steam explosion pulping wastewater with cattle manure: Focusing on degradation and inhibition of furfural.

In this study, an extended Anaerobic Digestion Model No.1, which considered the degradation and inhibition properties of furfural, was established and implemented to simulate the anaerobic co-digestion of steam explosion pulping wastewater and cattle manure in batch and semi-continuous modes. Batch and semi-continuous experimental data helped calibrate the new model and recalibrate the parameters related to furfural degradation, respectively. The cross-validation results showed the batch-stage calibration model accurately predicted the methanogenic behavior of all experimental treatments (R2 ≥ 0.959). Meanwhile, the recalibrated model satisfactorily matched the methane production results in the stable and high furfural loading stages in the semi-continuous experiment. In addition, recalibration results revealed the semi-continuous system tolerated furfural better than the batch system. These results provide insights into the anaerobic treatments and mathematical simulations of furfural-rich substrates.

Technology Roadmap for Flexible Sensors.

Humans rely increasingly on sensors to address grand challenges and to improve quality of life in the era of digitalization and big data. For ubiquitous sensing, flexible sensors are developed to overcome the limitations of conventional rigid counterparts. Despite rapid advancement in bench-side research over the last decade, the market adoption of flexible sensors remains limited. To ease and to expedite their deployment, here, we identify bottlenecks hindering the maturation of flexible sensors and propose promising solutions. We first analyze challenges in achieving satisfactory sensing performance for real-world applications and then summarize issues in compatible sensor-biology interfaces, followed by brief discussions on powering and connecting sensor networks. Issues en route to commercialization and for sustainable growth of the sector are also analyzed, highlighting environmental concerns and emphasizing nontechnical issues such as business, regulatory, and ethical considerations. Additionally, we look at future intelligent flexible sensors. In proposing a comprehensive roadmap, we hope to steer research efforts towards common goals and to guide coordinated development strategies from disparate communities. Through such collaborative efforts, scientific breakthroughs can be made sooner and capitalized for the betterment of humanity.

The Indices of Instantaneous Pulse Rate Variability Are Indicators for Daily Life Quality Assessment in Patients with COPD.

Chronic obstructive pulmonary disease (COPD) is a progressive respiratory illness. Questionnaires such as modified Medical Research Council (mMRC) dyspnea scale and COPD assessment test (CAT) are useful for COPD condition and life quality assessment. These questionnaires reflect how respiratory disorder affects daily life. Breathing and autonomic nervous system (ANS) usually regulate each other. Few studies discussed the ANS activity and daily life quality in patients with COPD. Therefore, this study aimed to find the relationship between daily life quality assessed by mMRC or CAT and ANS assessed by a novel method, instantaneous pulse rate variability (iPRV), a method indicating not only the ANS activity but also the peripheral response. The result showed that the change in mMRC and the change in low frequency power to high frequency power ratio, which usually represents the sympathetic activity in conventional heart rate variability analysis, had significant correlation (r = 0.63; p < 0.05). The change in CAT and the change in high frequency power (regulated by vagal nervous and respiratory system) or very high frequency power (new frequency band can be indicated in iPRV spectrum) had significant negative correlation (r = -0.64 and -0.55, respectively; p < 0.05 for both). This study showed the change in iPRV indices when the condition of COPD was improvement or exacerbation. This study presents a possible way to show how cardiovascular activity affects daily life quality in patients with COPD. Increase in LF or decrease in HF and VHF would cause poorer quality of daily life in patients with COPD. The result can also be a reference for patients with COPD to choose the breathing type to adjust rehabilitation and therapy program for ANS regulation to indicate or improve their daily life quality.

An Overview of Mesenchymal Stem Cell-based Therapy Mediated by Noncoding RNAs in the Treatment of Neurodegenerative Diseases.

Mesenchymal stem cells (MSCs) have become a promising tool for neurorestorative therapy of neurodegenerative diseases (NDDs), which are mainly characterized by the progressive and irreversible loss of neuronal structure and function in the central or peripheral nervous system. Recently, studies have reported that genetic manipulation mediated by noncoding RNAs (ncRNAs) can increase survival and neural regeneration of transplanted MSCs, offering a new strategy for clinical translation. In this review, we summarize the potential role and regulatory mechanism of two major types of ncRNAs, including microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), during the neurogenesis of MSCs with gene expression profile analyses. We also overview the realization of MSC-based therapy mediated by ncRNAs in the treatment of spinal cord injury, stroke, Alzheimer's disease and peripheral nerve injury. It is expected that ncRNAs will become promising therapeutic targets for NDD on stem cells, while the underlying mechanisms require further exploration.

A meta-analysis of leadership and intrinsic motivation: Examining relative importance and moderators.

This paper provides the first meta-analytic examination of the relationship between leadership and followers' intrinsic motivation. In particular, we examined 6 leadership variables (transformational, ethical, leader-member exchange, servant, empowering, and abusive supervision) using data from 50 independent samples and 21,873 participants. We found that transformational leadership, ethical leadership, leader-member exchange (LMX), servant leadership, and empowering leadership were positively related to intrinsic motivation, whereas abusive supervision was negatively linked to intrinsic motivation. Although these leadership styles were associated with intrinsic motivation, they varied considerably in their relative importance. Empowering, ethical, and servant leadership emerged as the more important contributors to intrinsic motivation than transformational leadership. LMX showed a similar contribution with transformational leadership to intrinsic motivation. Effectiveness of leadership styles in relation to intrinsic motivation varied by power distance, publication year, and journal quality. Drawing on our findings, we discuss the theoretical and practice implications.

Trade-Off of Metal Sites in Fe-Ni Bimetal Metal-Organic Frameworks for Efficient CO2 Photoreduction with Nearly 100% CO Selectivity.

This work disclosed the trade-off effect of two metal sites, which display distinct, key functionalities in naturally occurring and artificial catalysts for developing an advanced CO2 reduction system. To exploit the metal-organic frameworks (MOFs) as advanced catalysts, we prepared a series of Prussian blue analogues (FeNix PBAs) of tunable Ni/Fe molar ratio without changing the oxidation state of Fe and Ni for use as a photocatalyst in the CO2 reduction reaction (CRR). The FeNi0.66 PBA gives a superior CO yield rate (14.28 mmol·g-1·h-1) with nearly 100% CO selectivity, but the PBA would be basically CRR-inactive without either Ni or Fe. Experimental and calculation studies demonstrate that Fe and Ni display distinct functionalities. Specifically, Fe is an efficient mediator that boosts the electron transfer both from the photosensitizer to FeNix PBA and from FeNix PBA to CO2, and Ni serves as the active site for CO2 adsorption and reduction. Intriguingly, when there is already sufficient Ni in the catalyst, further increase of the Ni content gives marginal gains in the CO2 adsorption affinity that cannot offset the weakened electron transfer due to the Ni excess. The findings can help advance the design of bimetallic MOF catalysts that mimic naturally occurring bimetallic catalysts.

Humble leadership and its outcomes: A meta-analysis.

The importance of humble leadership has garnered attention from both researchers and practitioners. Unfortunately, despite the accumulation of recent findings on the effects of leader humility, a quantitative review remains scant. In addressing this void, this study is among the first to conduct a meta-analytic review of humble leadership and its outcomes. Eighty-four correlations (N = 16,534) from 53 independent studies are synthesized. The authors found that: (a) humble leadership is positively related to affective commitment (ρ = 0.56), affective trust (ρ = 0.62), creativity (ρ = 0.39), engagement (ρ = 0.40), leader-member exchange (LMX) (ρ = 0.58), job satisfaction (ρ = 0.51), organizational identification (ρ = 0.48), psychological empowerment (ρ = 0.33), self-efficacy (ρ = 0.24), task performance (ρ = 0.33), and voice (ρ = 0.34); and that (b) humble leadership contributes a significant incremental variance beyond transformational, servant, and ethical leadership in several crucial criterion variables, providing solid evidence for the construct's uniqueness. However, humble leadership does not explain incremental variance in some criterion variables, indicating that future studies should control for the influence of some positive leadership (e.g., transformational and servant leadership). Age, gender, study design, country, and year partially moderate the correlations of interest. We discuss our findings with caution and propose future research directions.