Polarity-Driven Fluorescence Monitoring of Lipid Droplet Dynamics in Dry Eye Disease.

The emergence of lipid droplets (LDs) has been recognized as cellular markers of ocular surface hyperosmosis, which is recognized as a fundamental mechanism driving dry eye disease (DED), while their dynamics during DED progression and therapy remains unlocked. For this purpose, an LD-specific fluorescent probe P1 is presented in this work that exhibits highly selective and sensitive emission enhancement in response to a decreased ambient polarity (Δf) from 0.209 to 0.021. The hydrophobic nature of P1 enables specific staining of LDs, facilitating visualization of changes in polarity within these cellular structures. Utilizing P1, we observe a decrease in polarity accompanied by an increase in the size and number of LDs in hyperosmotic human corneal epithelial cells (HCECs). Furthermore, interplays between LDs and cellular organelles such as mitochondria and the Golgi apparatus are visualized, suggesting the underlying pathogenesis in DED. Notably, the variations of LDs are observed after the inhibition of ferroptosis or activation of autophagy in hyperosmotic HCECs, implying the great potential of LDs as indicators for the design and efficacy evaluation of DED drugs regarding ferroptosis or autophagy as targets. Finally, LDs are confirmed to be overproduced in corneal tissues from DED mice, and the application of clinical eye drops effectively impedes these changes. This detailed exploration underscores the significant roles of LDs as an indicator for the deep insight into DED advancement and therapy.

Correlation of fluid-attenuated inversion recovery sequence vascular hyperintensity in magnetic resonance with collateral circulation and short-term clinical prognosis in acute ischemic stroke.

Background: Accurately assessing the prognosis of patient with large-scale cerebral infarction caused by acute middle cerebral artery (MCA) occlusion in the early stages of onset can help clinicians to actively and effectively intervene, thus reducing mortality and disability rates. This study set out to investigate the predictive value of fluid-attenuated inversion recovery vascular hyperintensity (FVH) on collateral circulation and clinical prognosis. Methods: The clinical data of 70 patients admitted to The First People's Hospital of Lianyungang from January 2018 to December 2021 with acute cerebral infarction due to occlusion of the proximal end of the M1 segment in the MCA were retrospectively collected. All patients had their first onset of disease and did not receive thrombolytic therapy at the time of onset. Subsequently, they underwent endovascular thrombectomy for treatment. The FVH and collateral vessel scores were derived according to patients' fluid-attenuated in version recovery (FLAIR) sequence and time-of-flight magnetic resonance angiography images. Based on the 90-day Modified Rankin Scale (mRS), patients were allocated to a good prognosis group (mRS ≤2) and a poor prognosis group (mRS =3-6). The correlation between the FVH and collateral vessel scores was assessed using the Spearman rank correlation test. Pearson correlation coefficient analysis was used to assess the correlation between FVH and the 90-day mRS together with the infarct size. Univariate analysis, multivariate binary logistic regression analysis, and receiver operating characteristic (ROC) curve analysis were adopted to identify those factors potentially. associated with the prognosis of patients with acute ischemic stroke (AIS). Results: Out of 70 patients with acute unilateral MCA occlusion (MCAO) who met the inclusion criteria, 62 showed positive FVH sign. These 62 patients were divided into a good prognosis group (n=32) and a poor prognosis group (n=30) based on the mRS score 90 days after discharge. The Spearman rank correlation test indicated that FVH was positively correlated with collateral vessel grade (Spearman rho =0.865; P<0.001); meanwhile, Pearson correlation coefficient analysis indicated that FVH score had moderate negative correlation with 90-day mRS score (r=-0.605; P<0.001). The results of multivariate binary logistic regression analysis indicated that collateral vessel grade and FVH score may be associated with the prognosis of patients with AIS, and the area under the curve (AUC) of FVH score was larger than collateral vessel grade (AUC =0.738). Conclusions: There was a positive correlation between FVH score and collateral vessel grade, and FVH score could indicate collateral circulation. FVH score was negatively correlated with 90-day mRS score and infarct volume and thus can predict clinical prognosis.

Clinical comprehensive treatment protocol for managing diabetic foot ulcers: A retrospective cohort study.

BACKGROUND: Diabetic foot ulcers (DFUs) are a common complication of diabetes, often leading to severe infections, amputations, and reduced quality of life. The current standard treatment protocols for DFUs have limitations in promoting efficient wound healing and preventing complications. A comprehensive treatment approach targeting multiple aspects of wound care may offer improved outcomes for patients with DFUs. The hypothesis of this study is that a comprehensive treatment protocol for DFUs will result in faster wound healing, reduced amputation rates, and improved overall patient outcomes compared to standard treatment protocols. AIM: To compare the efficacy and safety of a comprehensive treatment protocol for DFUs with those of the standard treatment protocol. METHODS: This retrospective study included 62 patients with DFUs, enrolled between January 2022 and January 2024, randomly assigned to the experimental (n = 32) or control (n = 30) group. The experimental group received a comprehensive treatment comprising blood circulation improvement, debridement, vacuum sealing drainage, recombinant human epidermal growth factor and anti-inflammatory dressing, and skin grafting. The control group received standard treatment, which included wound cleaning and dressing, antibiotics administration, and surgical debridement or amputation, if necessary. Time taken to reduce the white blood cell count, number of dressing changes, wound healing rate and time, and amputation rate were assessed. RESULTS: The experimental group exhibited significantly better outcomes than those of the control group in terms of the wound healing rate, wound healing time, and amputation rate. Additionally, the comprehensive treatment protocol was safe and well tolerated by the patients. CONCLUSION: Comprehensive treatment for DFUs is more effective than standard treatment, promoting granulation tissue growth, shortening hospitalization time, reducing pain and amputation rate, improving wound healing, and enhancing quality of life.

Bioinspired Genetic and Chemical Engineering of Protein Hydrogels for programable Multi-responsive Actuation.

Protein hydrogels with tailored stimuli-responsive features and tunable stiffness have garnered considerable attention due to the growing demand for biomedical soft robotics. However, integrating multiple responsive features toward intelligent yet biocompatible actuators remains challenging. Here, we report a facile approach that synergistically combines genetic and chemical engineering for the design of protein hydrogel actuators with programable complex spatial deformation. Genetically engineered silk-elastin-like proteins (SELPs) were encoded with stimuli-responsive motifs and enzymatic crosslinking sites via simulation-guided genetic engineering strategies. Chemical modifications of the recombinant proteins were also used as secondary control points to tailor material properties, responsive features, and anisotropy in SELP hydrogels. As a proof-of-concept example, diazonium coupling chemistry was exploited to incorporate sulfanilic acid groups onto the tyrosine residues in the elastin domains of SELPs to achieve patterned SELP hydrogels. These hydrogels can be programmed to perform various actuations, including controllable bending, buckling, and complex deformation under external stimuli, such as temperature, ionic strength, or pH. With the inspiration of genetic and chemical engineering in natural organisms, this work offers a predictable, tunable, and environmentally sustainable approach for the fabrication of programmed intelligent soft actuators, with implications for a variety of biomedical materials and bio-robotics needs. This article is protected by copyright. All rights reserved.

Imaging ultra-weak UV light below 100 pW cm-2 using a 4H-SiC photodetector with an Al2O3 interfacial layer.

Weak light detection is crucial in various practical applications such as night vision systems, flame monitoring, and underwater operations. Decreasing the dark current of a photodetector can effectively mitigate noises, consequently enhancing the signal-to-noise ratio and overall weak light detection performance. Herein, we demonstrate a 4H-SiC UV photodetector capable of detecting extremely weak UV light. This device comprises a photosensitive layer of 4H-SiC, two TiN electrodes and an atomically thin Al2O3 interfacial layer between TiN and the C surface of 4H-SiC. Under 360 nm UV light illumination, the proposed Al2O3 device demonstrates an ultra-low dark current of 18 fA, possibly benefiting from the effective passivation of interfacial carriers, and a boosted photo-to-dark current ratio of 6.7 × 107. Consequently, it achieves a weak-light detection limit as low as 31.8 pW cm-2, significantly outperforming the control device lacking Al2O3. When compared to previously reported SiC photodetectors, our Al2O3 device boasts an exceptional large linear dynamic range of 172 dB. Leveraging this, we construct a photodetector array capable of clearly imaging an object under ultra-weak light illumination below the 100 pW cm-2 level. The proposed photodetector represents a significant advancement in the development of highly sensitive image sensors for weak light detection.

SERPINH1 promoted the proliferation and metastasis of colorectal cancer by activating PI3K/Akt/mTOR signaling pathway.

BACKGROUND: Serpin peptidase inhibitor clade H member 1 (SERPINH1) was initially recognized as an oncogene implicated in various human malignancies. Nevertheless, the clinical relevance and functional implications of SERPINH1 in colorectal cancer (CRC) remain largely elusive. AIM: To investigate the effects of SERPINH1 on CRC cells and its specific mechanism. METHODS: Quantitative real-time polymerase chain reaction, western blotting analysis, The Cancer Genome Atlas data mining and immunohistochemistry were employed to examine SERPINH1 expression in CRC cell lines and tissues. A series of in-vitro assays were performed to demonstrate the function of SERPINH1 and its possible mechanisms in CRC. RESULTS: SERPINH1 demonstrated elevated expression levels in both CRC cells and tissues, manifested at both mRNA and protein tiers. Elevated SERPINH1 levels correlated closely with advanced T stage, lymph node involvement, and distant metastasis, exhibiting a significant association with poorer overall survival among CRC patients. Subsequent investigations unveiled that SERPINH1 overexpression notably bolstered CRC cell proliferation, invasion, and migration in vitro, while conversely, SERPINH1 knockdown elicited the opposite effects. Gene set enrichment analysis underscored a correlation between SERPINH1 upregulation and genes associated with cell cycle regulation. Our findings underscored the capacity of heightened SERPINH1 levels to expedite G1/S phase cell cycle progression via phosphatidylinositol 3-kinase/AKT/mechanistic target of rapamycin pathway activation, thereby facilitating CRC cell invasion and migration. CONCLUSION: These findings imply a crucial involvement of SERPINH1 in the advancement and escalation of CRC, potentially positioning it as a novel candidate for prognostic assessment and therapeutic intervention in CRC management.

Detecting Visible to Near-Infrared II Light via CsPbBr3 Nanocrystals/Y6 Heterojunctions.

In the endeavor to develop advanced photodetectors (PDs) with superior performance, all-inorganic perovskites, recognized for their outstanding photoelectric properties, have emerged as highly promising materials. Due to their unique electronic structure and band characteristics, the majority of all-inorganic perovskite materials are not sensitive to near-infrared (NIR) light. Here, we demonstrate the fabrication of a high-performance broadband PD comprising CsPbBr3 perovskite NCs/Y6 planar heterojunctions. The incorporation of Y6 not only facilitates charge transfer from CsPbBr3 NCs to Y6 for enhancing photodetection performance under visible illumination but also broadens the absorption spectrum range of the whole device toward the NIR regime. As a result, the heterojunction PD exhibits a photo-to-dark-current ratio above 105, a dynamic range of 149.5 dB, and an impressive lowest detection limit of incident power density of 1.6 nW/cm2 under 505 nm illumination. In the NIR regime, where photon energy is below the bandgap of CsPbBr3, electron-hole pairs can still be produced in the Y6 layer even when illuminated at 1120 nm. Consequently, photodetection is uniquely possible in PDs that incorporate heterojunctions when the illumination wavelength is longer than 565 nm. At 850 nm, the heterojunction device is capable of detecting light with power densities as low as 1.3 µW/cm2 corresponding to a LDR of 99.8 dB. The exceptional performance is attributed to the creation of a heterojunction between CsPbBr3 NCs and Y6. These findings propose a novel approach for developing broadband PDs based on perovskite NC materials.

High-Quality Solution-Processed Quasi-2D Perovskite for Low-Threshold Lasers.

Spin-coated quasi-two-dimensional halide perovskite films, which exhibit superior optoelectronic properties and environmental stability, have recently been extensively studied for lasers. Crystallinity is of great importance for the laser performance. Although some parameters related to the spin-coating process have been studied, the in-depth understanding and effective control of the acceleration rate on two-dimensional perovskite crystallization during spin-coating are still unknown. Here we investigate the effect of solvent evaporation on the microstructure of the final perovskite films during the spin-coating process. The crystallization quality of the film can be significantly improved by controlling solvent evaporation. As a result, the prepared quasi-2D perovskite film exhibits a stimulated emission threshold (pump: 343 nm, 6 kHz, 290 fs) of 550 nm as low as 16.2 µJ/cm2. Transient absorption characterization shows that the radiative biexciton recombination time is reduced from 738.5 to 438.3 ps, benefiting from the improved crystallinity. The faster biexciton recombination significantly enhanced the photoluminescence efficiency, which is critical for population inversion. This work could contribute to the development of low-threshold lasers.

Revealing the Development Patterns of the Mandibular Glands of Apis mellifera carnica Based on Transcriptomics and Morphology.

The mandibular gland in worker bees synthesizes and secretes the organic acids present in royal jelly, and its development directly affects yield and quality. Therefore, we aimed to analyze the differences in morphology and gene expression in the mandibular glands of Apis mellifera carnica worker bees of different ages (3, 6, 9, 12, and 16 d). We dissected their mandibular glands and performed morphological and transcriptomic analyses to investigate the development of the mandibular gland and the molecular regulatory mechanisms involved in royal jelly secretion. Microscopy revealed that mandibular gland development is likely completed in the early stages. There were no significant differences in the structural morphology or organelles involved in the secretion of royal jelly at different ages. Transcriptomics revealed a total of 1554 differentially expressed genes, which were mainly involved in fat metabolism, lipid transport, and energy metabolism. The extracellular matrix-receptor interaction pathway was significantly enriched and contributed to the royal jelly secretion process. These results elucidate the genetic basis of the role of the mandibular gland in royal jelly secretion in A. mellifera and provide a reference for the genetic improvement of bees with high royal jelly production in the future.

Jeans and language: kin networks and reproductive success are associated with the adoption of outgroup norms.

Traditional norms of human societies in rural China may have changed owing to population expansion, rapid development of the tourism economy and globalization since the 1990s; people from different ethnic groups might adopt cultural traits from outside their group or lose their own culture at different rates. Human behavioural ecology can help to explain adoption of outgroup cultural values. We compared the adoption of four cultural values, specifically speaking outgroup languages/mother tongue and wearing jeans, in two co-residing ethnic groups, the Mosuo and Han. Both groups are learning outgroup traits, including each other's languages through contact in economic activities, education and kin networks, but only the Mosuo are starting to lose their own language. Males are more likely to adopt outgroup values than females in both groups. Females of the two groups are no different in speaking Mandarin and wearing jeans, whereas males do differ, with Mosuo males being keener to adopt them than Han males. The reason might be that Mosuo men experience more reproductive competition over mates, as Mosuo men have larger reproductive skew than others. Moreover, Mosuo men but not others gain fitness benefits from the adoption of Mandarin (they start reproducing earlier than non-speakers). This article is part of the theme issue 'Social norm change: drivers and consequences'.

GAS6 attenuates sepsis-induced cardiac dysfunction through NLRP3 inflammasome-dependent mechanism.

Sepsis is a major health threat and often results in heart failure. Growth arrest-specific gene 6 (GAS6), a 75-kDa vitamin K-dependent protein, participates in immune regulation and inflammation through binding to AXL (the TAM receptor family). This study was designed to examine the myocardial regulatory role of GAS6 in sepsis. Serum GAS6 levels were increased in septic patients and mice while myocardial GAS6 levels were decreased in septic mice. Single-cell RNA sequencing further revealed a decline in GAS6 levels of nearly all cell clusters including cardiomyocytes. GAS6 overexpression via adeno-associated virus 9 (AAV9) overtly improved cardiac dysfunction in cecum ligation and puncture (CLP)-challenged mice, along with alleviated mitochondrial injury, endoplasmic reticulum stress, oxidative stress, and apoptosis. However, GAS6-elicited beneficial effects were removed by GAS6 knockout. The in vitro study was similar to these findings. Our data also noted a downstream effector role for NLRP3 in GAS6-initiated myocardial response. GAS6 knockout led to elevated levels of NLRP3, the effect of which was reconciled by GAS6 overexpression. Taken together, these results revealed the therapeutical potential of targeting GAS6/AXL-NLRP3 signaling in the management of heart anomalies in sepsis.

Molecular engineering and bioimaging applications of C2-alkenyl indole dyes with tunable emission wavelengths covering visible to NIR light.

As an important member of dyes, small-molecule fluorescent dyes show indispensable value in biomedical fields. Although various molecular dyes have been developed, full-color dyes covering blue to red region derived from a single chromophore are still in urgent demand. In this work, a series of dyes based on C2-alkenyl indole skeleton were synthesized, namely AI dyes, and their photophysical properties, cytotoxicity, and imaging capacity were verified to be satisfactory. Particularly, the maximal emission wavelengths of these dyes could cover a wide range from visible to NIR light with large Stokes shifts. Besides, the optical and structural discrepancies between the C2- and C3- alkenyl AI dyes were discussed in detail, and the theoretical calculations were conducted to provide insights on such structure-activity relationship. Finally, as a proof-of-concept, a fluorescent probe AI-Py-B capable of imaging endogenous ONOO- was presented, demonstrating the bioimaging potentials of these alkenyl indole dyes. This work is anticipated to open up new possibilities for developing dye engineering and bio-applications of natural indole framework.

Fluorescence Imaging of Diabetic Cataract-Associated Lipid Droplets in Living Cells and Patient-Derived Tissues.

Diabetic cataract (DC) surgery carries risks such as slow wound healing, macular edema, and progression of retinopathy and is faced with a deficiency of effective drugs. In this context, we proposed a protocol to evaluate the drug's efficacy using lipid droplets (LDs) as the marker. For this purpose, a fluorescent probe PTZ-LD for LDs detection is developed based on the phenothiazine unit. The probe displays polarity-dependent emission variations, i.e., lower polarity leading to stronger intensity. Especially, the probe exhibits photostability superior to that of Nile Red, a commercial LDs staining dye. Using the probe, the formation of LDs in DC-modeled human lens epithelial (HLE) cells is validated, and the interplay of LDs-LDs and LDs-others are investigated. Unexpectedly, lipid transfer between LDs is visualized. Moreover, the therapeutic efficacy of various drugs in DC-modeled HLE cells is assessed. Ultimately, more LDs were found in lens epithelial tissues from DC patients than in cataract tissues for the first time. We anticipate that this work can attract more attention to the important roles of LDs during DC progression.

[Effects of moxibustion at Yongquan (KI 1) on cognition function and lower limb motor function in patients with post-stroke cognitive impairment of kidney essence deficiency].

OBJECTIVE: To observe the effects of moxibustion at Yongquan（KI 1） on the cognitive function and lower limb motor function in patients with post-stroke cognitive impairment of kidney essence deficiency. METHODS: Eighty-four patients with post-stroke cognitive impairment of kidney essence deficiency were randomly divided into an observation group（42 cases，1 case dropped off）and a control group（42 cases，1 case dropped off）.The control group was treated with medication，electroacupuncture，rehabilitation training and repetitive transcranial magnetic stimulation（rTMS）；on the basis of the treatment as the control group，moxibustion at bilateral Yongquan（KI 1）was adopted in the observation group.Both groups were treated once a day，5 days a week with 2-day interval，4 weeks were required. The Montreal cognitive assessment (MoCA) score, mini-mental state examination (MMSE) score, Fugl-Meyer assessment-lower extremity (FMA-LE) score, Berg balance scale (BBS) score, functional independence measure (FIM) score, modified fall efficacy scale (MFES) score and scale for the differentiation of syndromes of vascular dementia (SDSVD) score before and after treatment were observed in the two groups. RESULTS: After treatment，the MoCA, MMSE, FMA-LE, BBS, FIM and MFES scores were higher than those before treatment in both groups (P<0.05), and the scores in the observation group were higher than those in the control group (P<0.05). After treatment，the SDSVD scores were lower than those before treatment in both groups (P< 0.05), and the SDSVD score in the observation group was lower than that in the control group (P< 0.05). CONCLUSION: Moxibustion at Yongquan（KI 1） can improve the cognitive function and motor and balance function of lower limbs in patients with post-stroke cognitive impairment of kidney essence deficiency，reduce the risk of fall and improve the quality of life.

The Photoperiod-Driven Cyclical Secretion of Pineal Melatonin Regulates Seasonal Reproduction in Geese (Anser cygnoides).

The photoperiod is the predominant environmental factor that governs seasonal reproduction in animals; however, the underlying molecular regulatory mechanism has yet to be fully elucidated. Herein, Yangzhou geese (Anser cygnoides) were selected at the spring equinox (SE), summer solstice (SS), autumn equinox (AE), and winter solstice (WS), and the regulation of seasonal reproduction via the light-driven cyclical secretion of pineal melatonin was investigated. We show that there were seasonal variations in the laying rate and GSI, while the ovarian area decreased 1.5-fold from the SS to the AE. Moreover, not only did the weight and volume of the pineal gland increase with a shortened photoperiod, but the secretory activity was also enhanced. Notably, tissue distribution further revealed seasonal oscillations in melatonin receptors (Mtnrs) in the pineal gland and the hypothalamus-pituitary-gonadal (HPG) axis. The immunohistochemical staining indicated higher Mtnr levels due to the shortened photoperiod. Furthermore, the upregulation of aralkylamine N-acetyltransferase (Aanat) was observed from the SS to the AE, concurrently resulting in a downregulation of the gonadotrophin-releasing hormone (GnRH) and gonadotropins (GtHs). This trend was also evident in the secretion of hormones. These data indicate that melatonin secretion during specific seasons is indicative of alterations in the photoperiod, thereby allowing for insight into the neuroendocrine regulation of reproduction via an intrinsic molecular depiction of external photoperiodic variations.

Biotic and abiotic stresses on honeybee health.

Honeybees are the most critical pollinators providing key ecosystem services that underpin crop production and sustainable agriculture. Amidst a backdrop of rapid global change, this eusocial insect encounters a succession of stressors during nesting, foraging, and pollination. Ectoparasitic mites, together with vectored viruses, have been recognized as central biotic threats to honeybee health, while the spread of invasive giant hornets and small hive beetles also increasingly threatens colonies worldwide. Cocktails of agrochemicals, including acaricides used for mite treatment, and other pollutants of the environment have been widely documented to affect bee health in various ways. Additionally, expanding urbanization, climate change, and agricultural intensification often result in the destruction or fragmentation of flower-rich bee habitats. The anthropogenic pressures exerted by beekeeping management practices affect the natural selection and evolution of honeybees, and colony translocations facilitate alien species invasion and disease transmission. In this review, the multiple biotic and abiotic threats and their interactions that potentially undermine bee colony health are discussed, while taking into consideration the sensitivity, large foraging area, dense network among related nestmates, and social behaviors of honeybees.

Symptoms mediate the relationship between childhood trauma and non-suicidal self-injury: A hospital-based study of adolescents with mood disorder.

BACKGROUND: Childhood trauma has a significant impact on the development of adolescents, which may lead to interpersonal and psychological problems. Determining the incidence and consequences of childhood trauma in psychiatric clinical practice is of great significance. METHODS: A survey was conducted among adolescents with mood disorders. Childhood Trauma Questionnaire (CTQ), the Adolescent Non-Suicidal-Self-Injury Behavior Function Assessment Scale (ANBFAS) and a series of psychological scales were filled face to face. Path analysis was used to examine the causation structure of childhood trauma-related symptoms. RESULTS: A total of 117 participants (74.5%) had experienced at least one type of trauma. Interpersonal and psychological features of adolescent patients with childhood trauma were detailed in this study. The path analysis model showed that the relationships between childhood trauma and NSSI were mediated by depressive symptoms and thinking disorders, respectively, whereas depressive symptoms individually mediated the correlation between childhood trauma and sleep disturbances in adolescent patients with psychiatric disorders (χ2 /df = 1.23). CONCLUSION: For adolescent patients with childhood trauma, psychological counseling for interpersonal relationships should start with families and peers. It is important to treat their depressive symptoms and thinking disorders and alleviate NSSI behavior and sleep disorders.

Effects of local domestication warrant attention in honey bee population genetics.

Honey bees, Apis mellifera, have for millennia been managed and exploited by humans and introduced into most suitable regions worldwide. However, given the lack of records for many introduction events, treating A. mellifera populations as native would predictably bias genetic studies regarding origin and evolution. Here, we used the Dongbei bee, a well-documented population, introduced beyond the natural distribution range approximately 100 years ago, to elucidate the effects of local domestication on animal population genetic analyses. Strong domestication pressure was detected in this population, and the genetic divergence between Dongbei bee and its ancestral subspecies was found to have occurred at the lineage level. Results of phylogenetic and time divergence analyses could consequently be misinterpreted. Proposing new subspecies or lineages and performing analyses of origin should thus strive to eliminate anthropogenic effects. We highlight the need for definitions of landrace and breed in honey bee sciences and make preliminary suggestions.

Atomic-level chemical reaction promoting external quantum efficiency of organic photomultiplication photodetector exceeding 108% for weak-light detection.

Low-cost, solution-processed photomultiplication organic photodetectors (PM-OPDs) with external quantum efficiency (EQE) above unity have attracted enormous attention. However, their weak-light detection is unpleasant because the anode Ohmic contact causes exacerbation in dark current. Here, we introduce atomic-level chemical reaction in PM-OPDs which can simultaneously suppress dark current and increase EQE via depositing a 0.8 nm thick Al2O3 by the atomic layer deposition. Suppression in dark current mainly originates from the built-in anode Schottky junction as a result of work function decrease of hole-transporting layer of which the chemical groups can react chemically with the bottom surface of Al2O3 layer at the atomic-level. Such strategy of suppressing dark current is not adverse to charge injection under illumination; instead, responsivity enhancement is realized because charge injection can shift from cathode to anode, of which the neighborhood possesses increased photogenerated carriers. Consequently, weak-light detection limit of the forwardly-biased PM-OPD with Al2O3 treatment reaches a remarkable level of 2.5 nW cm-2, while that of the reversely-biased control is 25 times inferior. Meanwhile, the PM-OPD yields a record high EQE and responsivity of 4.31 × 108% and 1.85 × 106 A W-1, respectively, outperforming all other polymer-based PM-OPDs.