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In this communication, we report a new class of oscillation mode, dome-shaped mode (DSM), in liquid crystal (LC) microlasers. A record high Q-factor over 24 000 is achieved in LC soft-matter microlasers. We successfully presented a proof-of-concept demonstration of red, green, blue (RGB) LC-DSM microlaser pixels with a 74% broader achievable color gamut than the standard RGB color space. Besides, the detection limit for acetone vapor molecules is as low as 0.5 ppm, confirming the excellent potential of the proposed LC-DSM microlaser in ultra-high sensitivity detection. Agency for Science, Technology and Research (A*STAR) Published version This work is supported by A*Star-AME-IRG-A20E5c0083, NRF-CRP23-2019-0007. V. D. T. acknowledges the support from the Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number 103.03- 2021.62. J. Y. also acknowledges the support from the National Science Fund for Distinguished Young Scholars of China (61925501), the Guangdong Introducing Innovative and Entrepreneurial Teams (2019ZT08X340) and Introducing Leading Talents (2019CX01X010) of ‘‘The Pearl River Talent Recruitment Program’’ of Guangdong Province.

Objective. This research mainly discusses the influence of prehospital emergency care (PHEC) on the rescue success rate and complication rate of senile patients with acute myocardial infarction (AMI). Methods. We selected 200 senile AMI patients who visited between January 2019 and January 2021, and retrospectively analyzed their clinical data. According to the differences in nursing methods, the patients were assigned to control group ( n = 90 ) and observation group ( n = 110 ), which were treated with routine nursing and PHEC, respectively. Intergroup comparisons were made in terms of rescue success rate, nursing efficacy, clinical parameters and complication rate. Results. After investigation, the nursing efficacy was higher in the observation group compared with the control group. Additionally, the observation group was observed with statistically shorter time to thrombolysis and hospital stay, as well as evidently lower mortality and complication rates. Conclusion. The above demonstrates that PHEC can effectively improve the rescue success rate and rescue efficacy, and facilitate the recovery of senile AMI patients, with a low complication rate compared with the routine care, which plays an important role in ensuring patients’ life safety and is worth popularizing clinically.

In recently developed organic semiconductors, the continuously improving sample purity makes the stability of the chemical bonds of organic materials themselves become a key factor in device stability, which provides greater uncertainty for the generation of "zeroth defect", and the spatial resolution of performance at different positions becomes particularly important. In this work, complete maps of electroluminescent, photoluminescent, and Raman scattering in the same area on an organic light-emitting diode during its operation have been achieved with a confocal spectrometer with multiple laser sources. The different spectral characters help to establish different regions and suggest the mechanism of degradation. In particular, Raman scattering has been shown to be very sensitive in a multilayer device to a change in thickness of several nanometers. In amorphous films with few defects, the very weak film uniformity, including the thickness and degree of aggregation, would induce dramatic degradation. The relatively thin and/or loosely textured region easily locally overheats and has the highest probability of "zeroth defect" generation. This method has high spatial resolution, a low level of damage to samples, good reproducibility, and multiple interconnected pieces of information, which is significant for online quality prediction and mechanistic analysis.

Pheochromocytomas (PCCs) are rare neuroendocrine tumors that originate from chromaffin cells in the adrenal gland. However, the cellular molecular characteristics and immune microenvironment of PCCs are incompletely understood. Here, we performed single-cell RNA sequencing (scRNA-seq) on 16 tissues from 4 sporadic unclassified PCC patients and 1 hereditary PCC patient with Von Hippel-Lindau (VHL) syndrome. We found that intra-tumoral heterogeneity was less extensive than the inter-individual heterogeneity of PCCs, a finding inconsistent with the widely-used PASS evaluation system. We further divided the unclassified PCC patients into two types, metabolism-type (marked by NDUFA4L2 and COX4I2) and kinase-type (marked by RET and PNMT), validated by immunohistochemical staining. Trajectory analysis of tumor evolution revealed that metabolism-type PCC cells display phenotype of consistently active metabolism and increased malignant potential, while kinase-type PCC cells showed decreased epinephrine synthesis and neuron-like phenotypes. Cellular communication analysis showed activation of the annexin pathway and a strong inflammation reaction in metabolism-type PCCs and activation of FGF signaling in the kinase-type PCC. Although multispectral immunofluorescence staining showed a lack of CD8+T cell infiltration in both metabolism-type and kinase-type PCCs, only the kinase-type PCC exhibited downregulation ofHLA-Ⅰmolecules that possibly regulated byRET, suggesting the potential of combined therapy with kinase inhibitors and immunotherapy for kinase-type PCCs; in contrast, the application of immunotherapy to metabolism-type PCCs (with antigen presentation ability) is likely unsuitable. Our study presents a single-cell transcriptomics-based molecular classification and microenvironment characterization of PCCs, providing clues for potential therapeutic strategies to treat PCCs.

Scientific understanding of trophic magnification factors (TMFs) is conducive to formulating environmental management measures. Trophic position (TP) of species is the key parameter in TMFs assessment. Nitrogen stable isotopes (δ

We analyzed the generation and dissemination of relevant information on wildlife utilization based on the African bush elephant (Loxodonta africana Blumenbach.), the tiger (Panthera tigris L.) and the totoaba, a species of marine fish, (Totoaba macdonaldi Gilbert) as examples, whose populations are more threatened by the illegal wildlife trade. We compared the illegal trade in wildlife with related information in order to find possible associations, searched for relevant information on major international websites to summarize similarities in information production and dissemination, and used a “Zhiwei” dissemination analysis platform to analyze the dissemination of information circulated at Microblog. The results show that the most influential information related to the trade in wildlife is mainly generated from news media websites and new self-media platforms, usually from non-governmental organizations concerned with wildlife protection. The main factors that affect the depth and breadth of disseminating relevant information on wildlife utilization include the participation of relatively influential opinion leaders, the verification ratio of forwarding users, the number of followers, and affective identification. Misleading information can stimulate and promote poaching and smuggling, regardless of their real market demand or their products. Therefore, all links in the course of information dissemination should be carefully examined in order to purify the information environment and reduce adverse effects of misleading information on wildlife protection.

Non-fullerene organic solar cells (NFOSC) demonstrate record efficiencies exceeding 16%. In comparison with cells with the fullerene-based acceptor, the NFOSC benefit from a longer wavelength absor...

The exciton migration mechanism in organic photovoltaic devices is still an ambiguity owing to the insufficient understanding of molecular arrangement on a microscopic scale. Herein, we reveal the relationship between the molecular stacking modes and exciton migration for a representative fused-ring electron acceptor, namely, ITIC. The precise molecular stacking patterns are extracted, and directional Coulombic couplings are calculated based on the information of a single-crystal structure, which proves the anisotropic character for exciton motion. The theoretical analysis results indicate ultrafast exciton migration along the head-to-tail stacking directions with maximum migration length of 330 nm in the finite lifetime of 1 ns. Experimentally, the exciton diffusion length is determined to be 183 nm by exciton-exciton annihilation measurement. This work reveals head-to-tail type intermolecular stacking induces strong anisotropic Coulombic coupling, leading to the ultrafast and long-range exciton migration in nonfullerene systems.

Prestressed concrete (PC) continuous girder-arch composite bridges, using concrete filled steel tubes (CFST) as the arch ribs to support the PC main girder, have gained their popularity in recently constructed large span bridges. The adoption of CFSTs brings many advantages, such as the concrete infill help to prevent the occurrence of local buckling in steel tubes, while the steel tubes can serve as framework for concrete core and strengthen the encased concrete. In order to achieve the above merits, the arch foots connecting the CFST arch ribs and PC girder are supposed to have sufficient strength and stiffness. However, the extensive use of CFST arch ribs showed that concrete cracking are commonly found at the arch foots. This paper studied the structural behavior of arch foot by employing a comprehensive numerical model. The influence of pumping pressure from concrete infill at construction stage on local stress of the arch foots was presented and discussed. The results indicated that the radial stress produced by pumping pressure at the joint zone squeezed the concrete around the arch foots, which resulted in significant hoop tensile stresses in the surrounding concrete. The outcomes of this study can provide technical support to improve the construction quality and structure stability, and optimize the construction procedures for this type of bridges.

Background: Annual health examination is recommended for the prevention and treatment of cardiovascular diseases and diabetes. However, whether it is effective for the prevention of hyperlipidemia and hyperglycemia remains unclear. Methods: A retrospective analysis of clinical samples using the laboratory information system was performed. From 2012 to 2019, 5043 participants (1755 males and 3288 females) have completed the annual health examination for 8 consecutive years, which was the follow-up group. In the same period, 136,994 participants (the control group) had a health examination only 1 time. Serum levels of fasting triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C) and glucose (GLU) were measured.Results: Compared with 2019 of the control group, serum TC and GLU in the 8th year of the follow-up group increased markedly in some of age groups (p < 0.001). Serum TG and TC in the 8th year were much higher compared with the 1st year of the follow-up group, especially for the female (p < 0.001). Moreover, the prevalence of hyperlipidemia and hyperglycemia in the 8th year showed significant increase compared with the 1st year of the follow-up group and 2019 of the control group (all p < 0.05).Conclusions: Annual health examination didn’t perform a positive effect in the prevention of hyperlipidemia and hyperglycemia. Health management should be paid more attention to prevent cardiovascular disease and diabetes.

The Architect HIV Ag/Ab Combo has been implemented worldwide as a screening test for more than ten years. However, its high sensitivity may lead to false-positive results in a low-prevalence setting.This study was carried out to evaluate the performance of the Architect HIV Ag/Ab Combo based on the sample-to-cutoff (S/CO) ratios, to explore the optimal cutoff value to predict HIV infection and reduce the frequency of false-positive results. A retrospective analysis of clinical samples using the Architect HIV Ag/Ab Combo between July 2011 and February 2020 was performed. The sensitivity, specificity, positive predictive value (PPV), and false-positive rate (FPR) were evaluated and the receiver operating characteristic curve (ROC) analysis was used to determine the optimal cutoff value to predict HIV infection.During the study period, 531 out of 692,155 samples were repeatedly reactive by the Architect HIV Ag/Ab Combo. The median S/CO value of HIV-positive were significantly higher than that of false-positive. The PPV of males (85.68%) was significantly higher than that of females (47.89%). The optimal cutoff value estimated by ROC analysis was 8.96 with the highest sum of sensitivity (100.00%) and specificity (100.00%) for males. However, for females, the optimal cutoff value was 26.97 with the highest sum of sensitivity (100.00%) and specificity (100.00%).For the Architect HIV Ag/Ab Combo, the optimal cutoff value needs to be set for the different genders to predict the final status of HIV infection reliably.

Meeting the challenge of direct electrically driven organic semiconductor lasers (OSLs), the design of OSL materials is being studied. Polarized species generally exist in conjugated organic materials and play an important role in the photophysics procedure; therefore, understanding these species is beneficial for designing novel OSL materials. Here, we use the amplified spontaneous emission effect as a medium to reveal a carbazole-benzothiadiazole-based polarized species induced by a charge transfer process. Spectroscopic analysis confirms that this polarized species that acted as a CT pair defect has a negative influence on the ASE stability and solid state fluorescent quantum yield. This inspires us to be cautious in terms of some specific molecular group combinations when designing OSL materials.

At least one third of sharks and their cartilaginous relatives (Class Chondrichthyes) meet the IUCN Red List Criteria for being threatened with extinction. Overfishing is the primary threat, with less than 4% of the world's shark catches managed for sustainability. The high‐value shark‐fin trade has gained the greatest attention as a conservation issue, yet there has been little research on shark‐fin consumer preferences, and how these might be leveraged to deliver sustainability goals. We used an online discrete choice experiment to explore preferences for price, quality, rarity, and finning among 2914 shark‐fin soup consumers in China. Overall, consumers prefer higher priced and rare shark‐fins, obtained without finning, yet we found three distinct groups with substantial heterogeneity between them. Our results provide evidence for the conspicuous consumption nature of shark‐fin use, but also suggest these preferences could be leveraged to incentivize responsible shark fishing. In addition, messaging for future unsustainable demand reduction should focus on shark‐finning and animal welfare as opposed species rarity and extinction.

The widespread dissemination of information related to wildlife utilization in new online media and traditional media undoubtedly impacts societal conservation concepts and attitudes, thus triggering public discussions on the relationship between conservation and utilization. A study on how public attitudes and concepts are affected by the related information on wildlife utilization is helpful to implement the scientific wildlife conservation and management strategies, and to propose targeted measures to optimize the information environment. We designed the questionnaire to investigate the public’s awareness and agreement with related information on wildlife utilization so as to measure how information with different dissemination channels, source types, and content orientation influenced the public’s concept of wildlife conservation and utilization. The questionnaire was distributed in seven major geographical regions throughout China. Out of a total of 1645 questionnaires that were collected, 1294 questionnaires were valid, with an effective rate of 78.7%. Results show that respondents had the greatest awareness of information on preventing unsustainable and illegal utilization, and the lowest awareness of information on promoting unsustainable utilization, and that awareness of information that against utilization was higher than that of information which supported sustainable utilization. At the same time, respondents showed the greatest agreement for information on preventing unsustainable utilization and the lowest agreement for information on promoting unsustainable utilization, also, their agreement with information that against utilization was higher than that for information which supported sustainable use. Respondents had a high level of awareness of information on wildlife related to COVID-19 provided by experts. Gender, age, the level of development of the city in which they live, education, vegetarianism, and religious beliefs all affected respondents’ agreement with related information on wildlife utilization. This research suggests that the publicity and education of scientific conservation methods should be emphasized in the future conservation education. In addition, scholars in the field of wildlife research should assume the role of ‘influencer’ and give full play to the scientific guidance of public opinion.

Sustainable wildlife management (SWM) is based on a synergy of traditional/local knowledge, advances in scientific knowledge, and fast-evolving economic and social circumstances. A widely accepted cornerstone of SWM globally is that conservation and utilization need to be effectively integrated, emphasizing the benefits humans can derive from biodiversity, thereby further encouraging people to protect and value wildlife though its management. However, with demand from biological resources growing at an unprecedented rate and the emergence of social media, conservationists must respond quickly to new challenges and conflicts associated with species management and public policy. For example, the rise of the “Compassionate Conservation” (CC) movement, fueled by social marketing and media, which promotes the welfare of individual animals, has introduced a set of challenges for conventional conservation management as it opposes most or all forms of wildlife utilization and hunting. CC advocates are increasingly influential at global and national policy levels, hence, it is imperative that conservationists are informed and aware of the future challenges from a rapidly changing global society. In this paper, we report the findings of a large semi-structured questionnaire in China which investigated the attitude of the urban public toward sustainable wildlife management (SWM) and wildlife conservation across a range of issues and identified the key socio-economic and demographic factor drivers for those attitudes. The survey was conducted from November 2018 to October 2020, across 15 cities randomly selected among China’s seven administrative geographic regions. The survey was initially conducted through face-to-face interviews, but later, due to COVID-19 restrictions, was completed via online questionnaires. A Likert seven-point scale method was used to score the public’s degree of agreement or disagreement for each question, a multivariate stepwise linear regression method was used to analyze whether the overall attitude of the respondents toward SWM and wildlife conservation was affected by their demographic characteristics, and a classification and regression tree (CART) was used to conduct an in-depth analysis of the issues with negative scores in the questionnaire, so as to understand how the respondents’ demographic characteristics affected the public’s attitude about such issues, which could supplement results obtained from the multivariate stepwise linear regression analysis. The results show that the public are broadly supportive of SWM, but only moderately so. On issues of “Animal Welfare and Rights,” “Wildlife Utilization and Captive Breeding,” and “Trophy Hunting”, the core concerns of the “Compassionate Conservation” movement and the overall public view are more antagonistic to conventional SWM. We also find specific demographic characteristics significantly influence attitudes about SWM, with vegetarians, those with religious beliefs, and with lower educational standards demonstrating weaker support for SWM. For younger people, “Animal Welfare and Rights” is a special concern, hence, we identify this as a key issue to be addressed for SWM and conservation in the future. Our research suggests that conservation organisations may need to adapt their management aims and practices to avoid direct conflict with the rising tide of animal rights sentiment, especially among the young. Furthermore, significant investment will be required to promote science-based conservation in social marketing on all social media platforms to help educate and engage the public with the science behind conservation management.

Different from the widely used constant discrimination factor Δ

Hot exciton luminogens capable of harvesting nonemissive triplet excitons via reverse intersystem crossing from high-order triplet (hRISC) to singlet have great potential in high-efficiency fluorescent organic light-emitting diodes (OLEDs). Although spin-orbit coupling (SOC) is regarded as a key factor affecting the RISC process, its effects on hot exciton materials are poorly understood. Herein, we design and synthesize two blue-emitting hot exciton luminogens, PABP and PAIDO, to study this issue by modulating the excited-state properties. Theoretical and experimental research contributions demonstrate that a stronger SOC between energetically close S1 (π-π*) and Tn (T3, n-π*) of PAIDO gives rise to faster and more efficient hRISC in comparison to that of PABP, leading to a higher external quantum efficiency and a higher exciton utilization efficiency. Crucially, the experimentally measured hRISC rate (khRISC) of hot exciton materials is on the order of 107 s-1, which is much faster than that of the thermally activated delayed fluorescence materials.

A novel, efficient, deep-blue fluorescent emitter mPAC, with a meta-connected donor-acceptor structure containing phenanthroimidazole (PPI) as the donor and phenylcarbazole-substituted anthracene (An-CzP) as the acceptor, was designed and synthesized. The meta-linkage provided a highly twisted molecular conformation, which efficiently interrupts the intramolecular π-conjugation, resulting in a deep-blue emission. The optimized nondoped device based on mPAC displayed a deep-blue emission with a narrow full width at half-maximum of 56 nm and Commission Internationale de L'Eclairage coordinates of (0.16, 0.09). The maximum external quantum efficiency (EQE

Urban forest parks are major ecological sites in the suburban areas of large cities with good forest vegetation and forest ecological environment, providing people with recreation, tourism, fitness and other suburban activities, and are an important component of the urban landscape system. The spatial density and development intensity of people, facilities and places in the park are higher than those in general forest areas, and the risk of forest disasters is high. To effectively prevent the occurrence of forest disasters and ensure the safety of touring, this paper takes Chengdu Longquan Mountain Forest Park as an example, and divides the key areas of the forest park into high risk areas, medium risk areas and low risk areas through coupled analysis of forest fire risk factors, forest pest risk factors and geological disaster risk factors, and builds a system of prevention, prevention, resistance and rescue for different risk levels. The system is a combination of prevention, resistance and rescue, with points leading to lines, and lines leading to surfaces, forming a disaster prevention system that combines “points, lines and surfaces”, with human, physical, technical and institutional prevention complementing each other, providing a model for reducing the risk of disasters and ensuring the health and safety of forest parks.

Taking African elephant (Loxodonta africana), tiger (Panthera tigris) and totoaba (Totoaba macdonaldi), whose populations are more threatened by illegal trade, as examples, this study aims to analyze the generation and dissemination mechanism of relevant information on wildlife utilization, and explore their association with illegal wildlife trade. We compared illegal wildlife trade with related information in order to find potential associations, searched for relevant information on major international websites to summarize similarities of related information production and dissemination, and used “Zhiwei” dissemination analysis platform to analyze the dissemination of information circulated at Microblog. The results show that the most influential information related to the use of wildlife is mainly generated from news media websites and new self-media platforms, mainly from non-governmental organizations concerned with wildlife protection. The main factors that affect the depth and breadth of disseminating relevant information on wildlife utilization include participation of relatively influential opinion leaders, the verification ratio of forwarding users, the number of fans, and affective commitment. Misleading information can stimulate and promote poaching and smuggling of wildlife, regardless of the real market demand for them or their products. Therefore, we should carefully examine all links in the course of information dissemination to purify the information environment and reduce the adverse effects of misleading information on wildlife protection.

The use of trophy hunting as a wildlife management option has been a highly controversial topic, especially in southern Africa, but trophy hunting has historically also taken place also throughout Asia. In China, trophy hunting was the topic of intense public discussion more than a decade ago, leading ultimately to the suspension of this practice in 2006. Yet, this debate was dominated by urban voices, with no formal consultation of rural populations from minorities such as the Tibetan herders who previously benefited financially from commercial trophy hunting acting as guides and who are also concerned about the negative impact of rising blue sheep numbers on livestock grazing. We used a discrete choice experiment econometric method to better understand the trade‐offs made by both urban and rural populations across China in relation trophy hunting as a rural development and wildlife management tool. We find that trophy hunting is supported by the majority of rural residents but opposed by most urban residents, although there is heterogeneity within both these groups. We recommend that policy‐making in this realm should be informed by a better understanding of the preferences of different stakeholders, including the local people who bear the costs of living with wildlife.

Biochemistry is an important curriculum for all medical students but has long been considered obscure and of very little or indirect relevance to medical or clinical practice, which markedly diminishes the enthusiasm and motivation of medical students in learning. Biochemistry teachers always face a tremendous challenge to deliver an attractive and high-quality lecture class. Inspired by convincing studies that show numerous benefits of undergraduate research, we tried to modify our teaching method in the past 5 years by incorporating classical scientific research stories into our traditional lecture class, such as the discovery of the semi-conservative DNA replication, telomeric DNA and telomerase, the tricarboxylic acid cycle (TCA cycle), and so on. Through this story-based teaching, we not only helped them deeply understand the textbook content, but also introduced the process of real scientific research to the students in an interesting way. Our efforts aim to combine the delivery of knowledge with the inspiration of students' active learning. We found that most students involved in our classes responded positively. As described in the survey, they were strongly attracted by those research stories; rather than feeling bored about the Biochemistry textbook, they experienced curiosity which fostered their active learning. They also learned to appreciate the beauty of science. More importantly, their impression on how the authentic science research was done was instructive for their critical thinking.

Ion-doped states are significant for improving the performance in organic semiconductor-based devices, which require clear characterization to understand their relationship with conductivity and charge transporting mechanisms. In this paper, Raman spectroscopy is used to track the evolution of a dianion-anion-neutral mixture in a perylene bisimide (PBI)-doped film under air, with z-scanning carried out in the confocal mode. The precise distribution for the different states along the film depth is realized within 3.5 μm. The whole film is clearly divided into three regions: the ion-poor state, transition region and ion-rich state. The ion ratio and distribution are strongly related to the film conductivity and the onset voltage shift. Changes in the distribution of the ionic species during oxidation and electrode catalysis are clearly recorded by z-scanning, which is beneficial for understanding the charge transfer properties as well as the mechanism underlying working devices.

光学陶瓷是一种透明的特种陶瓷, 可兼备单晶的高稳定性和玻璃、流体和其他非晶材料的大尺寸的优点, 是有潜力的激光增益介质. 因为对晶体尺寸和对称性有严格要求, 而且需要高温烧结过程, 只有少数无机非金属材料可用于制备光学陶瓷. 本文报道了一种由配位聚合物(或称金属—有机框架)组成的新型陶瓷. 通过简单地降低溶剂挥发速度, MAF-4(即SOD型二甲基咪唑锌, 也称ZIF-8)的纳米晶即可融合形成致密的陶瓷状块体, 甚至具有毫米级尺寸和高达84%可见光透过率. 该金属—有机光学陶瓷MOOC-1可以负载荧光染料sulforhodamine 640并保持其发光特性, 包括很高的量子产率63.6%和极低的放大自发辐射阈值31 μJ cm-2. 其他几种金属—有机框架的纳米晶也可以在类似条件下融合成陶瓷或光学陶瓷. 考虑到金属—有机框架的结构和功能多样性, 金属—有机陶瓷不但可用作光学器件, 还可能在吸附、分离、传感等相关领域展现潜力.

Neutral perylene bisimides (PBI) are well-known n-type organic semiconductors, with number of challenging electronic properties in their neutral and reduced states. We report the characteristic electronic properties of PBI anionic films. We unexpectedly discovered that pristine PBI dianion film showed p-type character, while oxidized dianion film (dominant neutral state with few radical anions) showed normal n-type semiconductor character based on Seebeck effect measurements. Both kinds of films exhibit high electrical conductivity with a potential for thermoelectric applications. The mechanism of polarity reversal is proposed.

Polycyclic aromatics (PCAs) possess excellent photoelectric properties, but the construction of such compounds has been a quite challenging subject of study, mainly due to very low solubility. Herein we report a precursor synthesis strategy for polycyclic aromatic conjugated polymers. A soluble precursor polymer, that containing fusible “double U-shaped aromatic” (DUA) and perylenetetracarboxydiimide (PDI) units, was firstly synthesized by Suzuki coupling. The stereo aromatic units in polymer backbone were found to be converted into polycyclic aromatic units, i.e. hexa-peri-hexabenzocoronene (HBC), by chemical or electrochemical oxidation, which resulted in a formation of insoluble polycyclic aromatic conjugated polymers. The electrochemical oxidations that occurred at the interface of electrode and solution exhibited higher cyclization reactivity and leads to the formation of high quality films on the electrode surface. Characterization by Raman and UV-visible (UV-Vis) spectroscopy validated the successful formation of this HBC structure. Some potential applications of such thin films are being explored, and here we focus on the characteristics of supercapacitors based on their excellent electrochemical properties.

Based on the “far-field” effect of surface plasma resonance, simultaneous red–green–blue electroluminescence enhancement by facile synthesized gold nanospheres were realized in this work, which would be difficult and complex to attain using wavelength-selected localized surface plasma resonance. The plasmonic “far-field” effect can simultaneously enhance the whole emission region in the white light range, because the enhancing regions from blue to red emission are largely overlapped. By doping gold nanospheres embedded in a poly(3,4-ethylene dioxythiophene):polystyrene sulfonic acid (PEDOT:PSS) layer, yield enhancement is achieved in more than 95% devices with the best enhancing ratio of 60% and the commission International de L’Eclairage (CIE) coordinate is stable at approximately (0.33, 0.36). The plasmonic “far-field” effect requires an ultra-low working concentration of Au NPs in picomolar magnitude, and shows little negative effect on the electronic process and light scattering, which has big potential in realizing highly efficient white organic light emitting diodes.

Gold nanoparticles are doped into a low refractive buffer layer (PMMA) to promote the amplified spontaneous emission (ASE) performance of a red-emissive polymer (MEH-PPV) in a slab waveguide device structure: Quartz/PMMA/MEH-PPV/Air. This facile device structure with the PMMA buffer layer results in a significant ∼12 fold enhancement of the ASE intensity and lowers the gain threshold by ∼40%. Remarkably, the enhanced ASE intensity beyond the gain threshold is much stronger than the control device without gold nanoparticles. Our results show that the surface plasmon resonance of gold nanoparticles in the slab waveguide structure can effectively increase the density of excited states (gain) and decrease energy losses (loss) and can be easily fabricated by solution processing methods. Our investigations indicate that buffer layer modification with metal nanoparticles exhibits huge potential for practical applications in the performance enhancement of organic lasers.

Electrochemical polymerization (EP) is a well-established method used in the fabrication of conjugated polymer films with optoelectronic function. The quality of the deposited film (including bulk compactness and surface morphology) is the crux of device application. In this work, an Au-nanoparticle modified ITO electrode is found to significantly improve the quality of an electrochemically polymerized film from a carbazole-based fluorescence precursor (OCBzC). This modified electrode lowers the oxidation potential of OCBzC by 40 mV and improves the redox reversibility, which is suitable for limiting the side-reactions during the redox induced polymerization at the electrode interface. Such an Au-nanoparticle modified ITO electrode also shows significant electro-catalysis and induced interfacial nucleation effects, and increases the diffusion coefficients of OCBzC by 25% and the interfacial electron-transfer rate by 90%. As a result, the nucleation rate of the electro-deposited products is increased and electro-polymerized films with more smooth and compact morphology are formed. The de-doped film shows a strong luminescence and lower leak current when employed in an organic light-emitting diode (OLED), especially on a pixel microelectrode.

African elephants are iconic species threatened by poaching and China was considered as one of the main destinations for illegally sourced ivory. In this article we combine two surveys of ivory carving enterprises with other data sets, including Chinese government seizure statistics, market prices for illegal ivory and substitute goods, to understand the impact of enforcement and demand reduction measures on ivory prices and poaching. Our analysis indicates the strong enforcement measures to combat ivory smuggling temporarily suppressed the tendency of illegal trade while stimulating a steep rise in illegal ivory prices thereafter. Peaking in 2012–2013, prices thereafter fell due to government measures to reduce demand under China's ‘Ecological Civilization’ programme and the announcement of ‘The Eight-point Regulation of the Centre’. Our survey suggests that most Chinese carving enterprises were intending to close or to diversify their business activities away from ivory carving as a result of the total ban on domestic ivory trading by 31st December 2017. And China had banned domestic ivory trade for over half a year and all ivory carving enterprises closed their ivory business activities since this domestic ban. In order to prevent ivory demand in other countries that may undermine Chinese efforts, we argue that other countries now also need to adopt multifaceted actions to curtail their domestic ivory trade. Keywords: Elephant poaching, Ivory, Trade ban, Demand reduction, Enforcement

Purely organic electroluminescent materials, such as thermally activated delayed fluorescent (TADF) and triplet-triplet annihilation (TTA) materials, basically harness triplet excitons from the lowest triplet excited state (T1 ) to realize high efficiency. Here, a fluorescent material that can convert triplet excitons into singlet excitons from the high-lying excited state (T2 ), referred to here as a "hot exciton" path, is reported. The energy levels of this compound are determined from the sensitization and nanosecond transient absorption spectroscopy measurements, i.e., small splitting energy between S1 and T2 and rather large T2 -T1 energy gap, which are expected to impede the internal conversion (IC) from T2 to T1 and facilitate the reverse intersystem crossing from the high-lying triplet state (hRISC). Through sensitizing the T2 state with ketones, the existence of the hRISC process with an ns-scale delayed lifetime is confirmed. Benefiting from this fast triplet-singlet conversion, the nondoped device based on this "hot exciton" material reaches a maximum external quantum efficiency exceeding 10%, with a small efficiency roll-off and CIE coordinates of (0.15, 0.13). These results reveal that the "hot exciton" path is a promising way to exploit high efficient, stable fluorescent emitters, especially for the pure-blue and deep-blue fluorescent organic light-emitting devices.

A correction to this paper has been published: https://doi.org/10.1007/s11676-021-01306-y.

The debates about the extent to which phytoplankton in freshwater ecosystems are regulated by top-down or bottom-up forces have been ongoing for decades. This study examines the effects of bottom-up and top-down factors on the phytoplankton functional groups in a eutrophic lake. Phytoplankton and zooplankton were sampled and physical-chemical variables measured from May 2019 to October 2019 in Lake Hulun, China. Approximately 43 phytoplankton species were observed and grouped into 23 functional groups. For the zooplankton, about 27 species were observed and classified into 8 functional groups. The study revealed that the bottom-up effects of physical-chemical variables on some phytoplankton functional groups was stronger than the top-down effects of zooplankton. Water temperature (WT), total phosphorus (TP), total nitrogen (TN), conductivity (Cond), water transparency (SD), and dissolved oxygen (DO) significant influence the biomass of the phytoplankton functional groups. The biomass of phytoplankton functional groups was influenced positively by nutrient availability likely because nutrients influence the growth and reproduction of phytoplankton in freshwater. WT and DO had a positive influence on biomass of phytoplankton functional groups. Conversely, phytoplankton biomass revealed a decreasing trend when SD and Cond significantly increased. This study showed that zooplankton functional groups were positively correlated with phytoplankton biomass implying that the top-down control of phytoplankton by the zooplankton in the lake is not strong enough to produce a negative effect. It is evident that the zooplankton functional groups in Lake Hulun are controlled more by bottom-up force than top-down.