Metasurface assisted terahertz (THz) real-time and label-free biosensors have attracted intense attention. However, it is still challenging for specific detection of highly absorptive liquid samples ...with high sensitivity in the THz range. Here, we incorporated graphene with THz metasurface into a microfluidic cell for sensitive biosensing. The proposed THz graphene-metasurface microfluidic platform can effectively reduce the volume of the sample solution and boost the interaction between biomolecules and THz waves, thus enhancing the sensitivity. As a proof of concept, comparative experiments using other three kinds of microfluidic cells (pure microfluidic cell, metasurface-based microfluidic cell and graphene-based microfluidic cell) were conducted to explore and verify the sensing mechanism, which evidences the high sensitivity of delicate sensing based on the hybrid graphene-metasurface THz microfluidic device. Furthermore, to perform biosensing applications on that basis, specific aptamers were modified on the graphene-metasurface, enabling DNA sequences of foodborne pathogen Escherichia coli O157:H7 to be recognized. Based on the THz microfluidic biosensor, 100 nM DNA short sequences can be successfully detected. The sensing results of antibiotics and DNA based on the graphene-metasurface microfluidic biosensor confirm the superiority of the proposed design and considerable promise in THz biosensing. The novel sensing platform provides the merits of enabling highly sensitive, label-free, low-cost, easy to use, reusable, and real-time biosensing, which opens an exciting prospect for nanomaterial-metasurface hybrid structure assisted THz label-free biosensing in liquid environment.
•A novel microfluidic platform integrating graphene with metasurface is reported.•Sensitive terahertz molecular detection in liquid environment is realized.•DNA sequences of foodborne pathogen can be recognized with high selectivity.•The biosensing capability can be restored through a simple regeneration process.•The hybrid metasurface-graphene structure can improve the sensitivity.
Home-sharing platforms, such as Airbnb, Inc., serve as a peer-to-peer (P2P) marketplace for users to rent out empty lodging spaces to others for a short-term period. The concerns over the disruptive ...nature of such home-sharing platforms, particularly on the traditional industries and the neighborhood in which the lodgings are provided, have resulted in lawmakers imposing or considering to impose short-term rental (STR) regulations. This research, which anchors on the public interest theory and the prospect theory, examines the overall effect of STR regulation and identifies effective individual regulatory passages on the supply side of P2P home-sharing platforms. Our subsequent empirical analysis results suggest that the regulatory intervention is less likely to restrain the growth of the home-sharing economy in the long-run even though there is a short-term deterrent effect of STR regulation on new entrants to the market. Different regulatory passages exert varying effects on the new entrants and the exit of the incumbent hosts. In specific, three regulatory passages, namely, cap, standards, and eviction restrictions, have a parsimonious effect on containing both the new listing and the delisting. This study not only advances our understanding of the emergent sharing economy in the space of STR services but also provides insights into the effectiveness of STR regulatory passages in containing STR activities.
High-speed underwater optical wireless communication (UOWC) was achieved using an 80 μm blue-emitting GaN-based micro-LED. The micro-LED has a peak emission wavelength of ~440 nm and an underwater ...power attenuation of 1 dB/m in tap water. The -3 dB electrical-to-optical modulation bandwidth of the packaged micro-LED increases with increasing current and saturates at ~160 MHz. At an underwater distance of 0.6 m, 800 Mb/s data rate was achieved with a bit error rate (BER) of 1.3 × 10
, below the forward error correction (FEC) criteria. And we obtained 100 Mb/s data communication speed with a received light output power of -40 dBm and a BER of 1.9 × 10
, suggesting that UOWC with extended distance can be achieved. Through reflecting the light emission beam by mirrors within a water tank, we experimentally demonstrated a 200 Mb/s data rate with a BER of 3.0 × 10
at an underwater distance of 5.4 m.
Klebsiella michiganensis is a pathogenic bacterium related to mulberry (Morus alba L.) wilt disease. Here, Luo et al present the complete genome sequence of Klebsiella michiganensis AKKL-001, ...isolated from diseased mulberry in Guangxi, China. The complete genome sequence of K. michiganensis AKKL-001 was characterized by a 6,149,586-base circular chromosome with a 55.80% GC content. This genome will contribute to epidemiological and comparative genomic studies of genus Klebsiella. To their knowledge, this is the first genome announcement of a mulberry-associated bacterium from the genus Klebsiella. Mulberry (Morus alba L.) is a woody plant belonging to the family Moraceae and is widespread in Asia, Africa, and Europe and has diverse beneficial characters.
Abstract The issue of academic procrastination is highly prevalent among university students. It not only has a deterimental effect on students' academic performance but also poses a risk to their ...physical and mental well-being. Anxiety, as a negative emotion, has attracted researchers’ attention in relation to academic procrastination. Research indicates a correlation between state anxiety and academic procrastination, but the underlying mechanisms that drive this association remain unclear. When individuals experience ego-depletion, it can lead to psychological exhaustion, subsequently leading to procrastination. Gender role conceptions, shaped by sociocultural and psychological mechanisms, have profound implications on individuals’ cognition, emotions, and behaviors. This study primarily aims to explore the relationship between state anxiety and academic procrastination among university students, with a particularly focus on the mediating role of ego-depletion and the moderating role of gender. A survey using the State Anxiety Scale, Ego-Depletion Scale, and Irrational Procrastination Scale was administered to 3370 undergraduates. State anxiety shows positive correlations with ego depletion and academic procrastination ( r = 0.665, p < 0.01; r = 0.491, p < 0.01), while ego depletion is also positively linked to academic procrastination ( r = 0.500, p < 0.01). State anxiety serves as a positive predictor of academic procrastination, with a confidence interval of 95% 0.626, 0.696; additionally, ego depletion partially mediates the relationship between state anxiety and academic procrastination, with a confidence interval of 95% 0.168, 0.251. Gender acts as a moderator in directly predicting the impact of state anxiety on academic procrastination and in the latter stage of mediating the effect of ego depletion. State anxiety can significantly and positively predict academic procrastination among university students. Ego-depletion partially mediates the relationship between state anxiety and academic procrastination. The direct predictive effect of state anxiety on academic procrastination, as well as the mediating role of ego-depletion, is moderated by gender. This provides educators and university students themselves with reference for addressing the issue of academic procrastination.
In serving college students with mental disorders, on-campus mental health professionals have been lacking integrative theoretical frameworks to guide their missions of prevention, remedy, and ...development facilitation. In the current paper, we propose the positive clinical psychology as a theoretically and practically valuable framework for these missions by narratively reviewing the preventive, remedial, and developmental mechanisms derived from the theory and summarizing the most recent empirical evidence that supports each mechanism. We further discuss why and how these mechanisms and findings can be applied to on-campus mental health services to facilitate the resilience and optimal development of college students with mental disorders. Particularly, the use of resilience-focused and strength-based intervention strategies are promoted for services.In serving college students with mental disorders, on-campus mental health professionals have been lacking integrative theoretical frameworks to guide their missions of prevention, remedy, and development facilitation. In the current paper, we propose the positive clinical psychology as a theoretically and practically valuable framework for these missions by narratively reviewing the preventive, remedial, and developmental mechanisms derived from the theory and summarizing the most recent empirical evidence that supports each mechanism. We further discuss why and how these mechanisms and findings can be applied to on-campus mental health services to facilitate the resilience and optimal development of college students with mental disorders. Particularly, the use of resilience-focused and strength-based intervention strategies are promoted for services.
Abstract
The effects of thermally and Fe(II) activated potassium persulfate (PPS) on sludge dewatering performance were compared systematically. Sludge dewaterability was monitored by measuring ...capillary suction time (CST) and sludge specific resistance to filtration (SRF), and the degradation effect was characterized by chemical oxygen demand (COD), total organic carbon (TOC), ammonia nitrogen (NH4+-N) and extracellular polymeric substances (EPS). The change of extracellular polymer substance (EPS) including soluble, loosely bound and tightly bound EPS (S-EPS, LB-EPS and TB-EPS) with time and PPS dosage was monitored to discuss the oxidation efficiency of thermally and Fe(II) activated PPS. Sludge supernatant was analyzed by three-dimensional fluorescence excitation–emission spectra (3D-EEM) to confirm the protein transformation. The result showed that sludge dewaterability in terms of CST and SRF were enhanced with increasing PPS dosage and condition time of two activated methods. While Fe(II) activated PPS could reduce sludge CST and SRF to preferred values at low PPS dosage and short condition time. Meanwhile, sludge degradation effect was also more obvious. Mechanically, sludge TB-EPS in proteins and polysaccharides converted to SB-EPS was faster with Fe(II) activated PPS. In addition, thermally activated PPS tended to oxidize the protein in the supernatant first.
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•Meta-analysis of the effects of litter manipulation on soil nitrogen (N) cycling.•Litter addition increased soil N pools whereas litter removal reduced them.•Responses of soil net N ...mineralization were higher in dry and cold regions.•Soil available N and N2O emission increased with increasing litter input rate.•Litter addition increased soil N leaching mainly via DON leaching.
Alterations in aboveground plant litter inputs due to global climate change can strongly change soil nitrogen (N) cycling, which will influence soil processes and functions. However, a comprehensive evaluation for the effects of altered litter inputs on soil N cycling is not available. We evaluated these effects using a global meta-analysis based on 1829 observations from 119 studies across different ecosystems including forests, shrublands and grasslands. Results showed that litter addition significantly increased soil N pools including total N (TN), dissolved organic N (DON), ammonium (NH4+), nitrate (NO3–) and microbial biomass N (MBN) by 4–––24 %, while litter removal decreased them by 10–––42 %. High initial soil TN pool weakened the positive effect of litter addition on soil TN. Moreover, litter addition significantly increased soil net N mineralization (+19 %), DON leaching (+56 %) and nitrous oxide (N2O) emission (+27 %), whereas litter removal reduced net N mineralization (-10 %) and increased NO3– leaching (+51 %). The response of soil net N mineralization to litter addition was stronger in broadleaved forests than that in coniferous forests, and negatively correlated with mean annual temperature and precipitation. The responses of soil TN, NH4+, NO3–, MBN and N2O emission to litter manipulation increased with increasing litter input rates. Therefore, altered litter inputs had strong effects on soil N cycling and these effects were regulated by soil N status, ecosystems, climates and experimental conditions. Our results provide insights into understanding how altered plant litter input affects soil N cycling and help better assess the soil processes under global climate change.
The inability of wounds to heal effectively through normal repair has become a burden that seriously affects socio-economic development and human health. The therapy of acute and chronic skin wounds ...still poses great clinical difficulty due to the lack of suitable functional wound dressings. It has been found that dressings made of polyurethane exhibit excellent and diverse biological properties, but lack the functionality of clinical needs, and most dressings are unable to dynamically adapt to microenvironmental changes during the healing process at different stages of chronic wounds. Therefore, the development of multifunctional polyurethane composite materials has become a hot topic of research. This review describes the changes in physicochemical and biological properties caused by the incorporation of different polymers and fillers into polyurethane dressings and describes their applications in wound repair and regeneration. We listed several polymers, mainly including natural-based polymers (e.g., collagen, chitosan, and hyaluronic acid), synthetic-based polymers (e.g., polyethylene glycol, polyvinyl alcohol, and polyacrylamide), and some other active ingredients (e.g., LL37 peptide, platelet lysate, and exosomes). In addition to an introduction to the design and application of polyurethane-related dressings, we discuss the conversion and use of advanced functional dressings for applications, as well as future directions for development, providing reference for the development and new applications of novel polyurethane dressings.
Abstract
Electrolysis zero-valent iron activated peroxymonosulfate (EZVI-PMS) was applied to enhance sludge dewaterability and disintegration performance. Sludge dewaterability was characterized by ...capillary suction time (CST), specific resistance to filtration (SRF), and disintegration performance was explored by measuring sludge DNA content, ammonia nitrogen, chemical oxygen demand (COD), extracellular polymeric substances (EPS) and dissolved organic carbon (DOC). EPS, including soluble EPS (SB-EPS), loosely bound EPS (LB-EPS), and tightly bound EPS (TB-EPS) were analyzed by three dimensional fluorescence excitation-emission spectrum (3D-EEM) to confirm the proteins' transformation tendency. DOC, protein and polysaccharide in EPSs were quantified to investigate the conditioning mechanism. The results showed that sludge CST and SRF were reduced significantly when the current was 0.2 A and PMS dosage was 130 mg/gDS with the reductions of 43.8% and 74.1%, respectively, and DNA was released from sludge cells to the liquid phase. Mechanically, sludge TB-EPS converted to SB-EPS with DOC in TB-EPS decreasing from 367.0 mg/L to 210 mg/L, while DOC in SB-EPS increased from 44 mg/L to 167.4 mg/L. Besides, the changes of protein and polysaccharide contents in SB-EPS and TB-EPS were similar to DOC, and protein in TB-EPS transformed to other protein-like or organic substances obviously.
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