Search

In the hopes of observing the highest-energy neutrinos (E>1 EeV) populating the Universe, both past (RICE, AURA, ANITA) and current (RNO-G, ARIANNA, ARA and TAROGE-M) polar-sited experiments exploit the impulsive radio emission produced by neutrino interactions. In such experiments, rare single event candidates must be unambiguously identified above backgrounds. Background rejection strategies to date primarily target thermal noise fluctuations and also impulsive radio-frequency signals of anthropogenic origin. In this paper, we consider the possibility that ‘fake’ neutrino signals may also be generated naturally via the ‘triboelectric effect.’ This broadly describes any process in which force applied at a boundary layer results in displacement of surface charge, leading to the production of an electrostatic potential difference ΔV. Wind blowing over granular surfaces such as snow can induce such a potential difference, with subsequent coronal discharge. Discharges over timescales as short as nanoseconds can then lead to radio-frequency emissions at characteristic MHz–GHz frequencies. Using data from various past (RICE, AURA, SATRA, ANITA) and current (RNO-G, ARIANNA and ARA) neutrino experiments, we find evidence for such backgrounds, which are generally characterized by: (a) a threshold wind velocity which likely depends on the experimental trigger criteria and layout; for the experiments considered herein, this value is typically O(10 m/s), (b) frequency spectra generally shifted to the low-end of the frequency regime to which current radio experiments are typically sensitive (100–200 MHz), (c) for the strongest background signals, an apparent preference for discharges from above-surface structures, although the presence of more isotropic, lower amplitude triboelectric discharges cannot be excluded.

Abstract The TAROGE-M radio observatory is a self-triggered antenna array on top of the ∼2700 m high Mt. Melbourne in Antarctica, designed to detect impulsive geomagnetic emission from extensive air showers induced by ultra-high energy (UHE) particles beyond 1017 eV, including cosmic rays, Earth-skimming tau neutrinos, and particularly, the “ANITA anomalous events” (AAE) from near and below the horizon. The six AAE discovered by the ANITA experiment have signal features similar to tau neutrinos but that hypothesis is in tension either with the interaction length predicted by Standard Model or with the flux limits set by other experiments. Their origin remains uncertain, requiring more experimental inputs for clarification. The detection concept of TAROGE-M takes advantage of a high altitude with synoptic view toward the horizon as an efficient signal collector, and the radio quietness as well as strong and near vertical geomagnetic field in Antarctica, enhancing the relative radio signal strength. This approach has a low energy threshold, high duty cycle, and is easy to extend for quickly enlarging statistics. Here we report experimental results from the first TAROGE-M station deployed in January 2020, corresponding to approximately one month of livetime. The station consists of six receiving antennas operating at 180-450 MHz, and can reconstruct source directions of impulsive events with an angular resolution of ∼0.3°, calibrated in situ with a drone-borne pulser system. To demonstrate TAROGE-M's ability to detect UHE air showers, a search for cosmic ray signals in 25.3-days of data together with the detection simulation were conducted, resulting in seven identified candidates. The detected events have a mean reconstructed energy of 0.95-0.31+0.46 EeV and zenith angles ranging from 25° to 82°, with both distributions agreeing with the simulations, indicating an energy threshold at about 0.3 EeV. The estimated cosmic ray flux at that energy is 1.2-0.9+0.7 × 10-16 eV-1 km-2 yr-1 sr-1, also consistent with results of other experiments. The TAROGE-M sensitivity to AAEs is approximated by the tau neutrino exposure with simulations, which suggests comparable sensitivity as ANITA's at around 1 EeV energy with a few station-years of operation. These first results verified the station design and performance in a polar and high-altitude environment, and are promising for further discovery of tau neutrinos and AAEs after an extension in the near future.

Bears harbor various endoparasites that pose risks to humans and other animals. However, information on parasitic infections in Asiatic black bears in South Korea (Korea) is limited, and potential hazards still exist because of the close contact between bears and humans on bile farms. The present study was conducted to assess the gastrointestinal parasite infection status in captive Asiatic black bears (Ursus thibetanus) at bile farms in Korea. Additionally, we aimed to characterize the molecular aspects of Baylisascaris transfuga (Nematoda: Ascarididae), the sole species investigated throughout the study. Fecal examinations were performed on a total of 84 fecal samples collected from three bear farms in Hwacheon-gun (gun = County) and Donghae-si (si = City), Gangwon-do (do = Province), and Dangjin-si, Chungcheongnam-do. Eggs were identified morphologically, and an adult worm expelled in the feces was analyzed molecularly using the partial cytochrome c oxidase subunit 1 and 2 (cox1 and cox2) gene markers. The prevalence of helminthic eggs was 10.7 %, identified as B. transfuga based on morphological characteristics. The eggs, which were oval and brown with thick shells, had a mean length of 87.3 ± 8.9 μm on the long axis and 70.7 ± 6.1 μm on the short axis (n = 30). An adult female roundworm found in the feces of one individual, measuring 27 cm in length and 0.4 cm in width, was also identified as same species through genetic methods. Herein, we described the prevalence of B. transfuga in captive bears in Korea and its molecular characteristics for the first time. Additionally, we reviewed the sequences of the genus Baylisascaris available in the International Nucleotide Sequence Database Collection, noting that many of these sequences often have ambiguous or potentially incorrect identifications, complicating the understanding of their phylogenetic status. This investigation is part of disease screening efforts aimed at enhancing the welfare of captive bears prior to their imminent relocation to sanctuaries. Health monitoring and endoparasite control in farmed bears should be carried out in both veterinary and public health contexts., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Genetic variation leads to phenotypic variability in pluripotent stem cells that presents challenges for regenerative medicine. Although recent studies have investigated the impact of genetic variation on pluripotency maintenance and differentiation capacity, less is known about how genetic variants affecting the pluripotent state influence gene regulation in later stages of development. Here, we characterized expression of more than 12,000 genes in 127 donor-matched Diversity Outbred (DO) mouse embryonic stem cell (mESC) and neural progenitor cell (mNPC) lines. Quantitative trait locus (QTL) mapping identified 2,947 expression QTL (eQTL) unique to DO mNPCs and 1,113 eQTL observed in both mNPCs and mESCs with highly concordant allele effects. We mapped three eQTL hotspots on Chromosomes (Chrs) 1, 10, and 11 that were unique to mNPCs. Target genes of the Chr 1 hotspot were overrepresented for those involved in mRNA processing, DNA repair, chromatin organization, protein degradation, and cell cycle. Mediation analysis of the Chr 1 hotspot identified Rnf152 as the best candidate mediator expressed in mNPCs, while cross-cell type mediation using mESC gene expression along with partial correlation analysis strongly implicated genetic variant(s) affecting Pign expression in the mESC state as regulating the mNPC Chr 1 eQTL hotspot. Together these findings highlight that many local eQTL confer similar effects on gene expression in multiple cell states; distant eQTL in DO mNPCs are numerous and largely unique to that cell state, with many co-localizing to mNPC-specific hotspots; and mediation analysis across cell types suggests that expression of Pign early in development (mESCs) shapes the transcriptome of the more specialized mNPC state.

Glucagon-like peptide 1 receptor agonists (GLP-1RAs) are increasingly being used to treat diabetes and obesity. However, their effectiveness and risks have not yet been systematically evaluated in a comprehensive set of possible health outcomes. Here, we used the US Department of Veterans Affairs databases to build a cohort of people with diabetes who initiated GLP-1RA (n = 215,970) and compared them to those who initiated sulfonylureas (n = 159,465), dipeptidyl peptidase 4 (DPP4) inhibitors (n = 117,989) or sodium-glucose cotransporter-2 (SGLT2) inhibitors (n = 258,614), a control group composed of an equal proportion of individuals initiating sulfonylureas, DPP4 inhibitors and SGLT2 inhibitors (n = 536,068), and a control group of 1,203,097 individuals who continued use of non-GLP-1RA antihyperglycemics (usual care). We used a discovery approach to systematically map an atlas of the associations of GLP-1RA use versus each comparator with 175 health outcomes. Compared to usual care, GLP-1RA use was associated with a reduced risk of substance use and psychotic disorders, seizures, neurocognitive disorders (including Alzheimer's disease and dementia), coagulation disorders, cardiometabolic disorders, infectious illnesses and several respiratory conditions. There was an increased risk of gastrointestinal disorders, hypotension, syncope, arthritic disorders, nephrolithiasis, interstitial nephritis and drug-induced pancreatitis associated with GLP-1RA use compared to usual care. The results provide insights into the benefits and risks of GLP-1RAs and may be useful for informing clinical care and guiding research agendas., Competing Interests: Competing interests: Y.X. and Z.A.A. are uncompensated consultants for Pfizer. No other potential competing interests relevant to this article are reported., (© 2025. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Perovskite nanocrystals (PNCs) are promising active materials because of their outstanding optoelectronic properties, which are finely tunable via size and shape. However, previous synthetic methods such as hot-injection and ligand-assisted reprecipitation require a high synthesis temperature or provide limited access to homogeneous PNCs, leading to the present lack of commercial value and real-world applications of PNCs. Here, we report a room-temperature approach to synthesize PNCs within a liquid crystalline antisolvent, enabling access to PNCs with a precisely defined size and shape and with reduced surface defects. We demonstrate that elastic strains and long-range molecular ordering of the liquid crystals play a key role in not only regulating the growth of PNCs but also promoting high surface passivation of PNCs with ligands. The approach is a simple, rapid, and room-temperature process, yet it enables access to highly homogeneous PNCs on a mass scale with substantially reduced surface defect states leading to significantly enhanced optoelectronic features. Our results provide a versatile and generalizable strategy to be broadly compatible with a range of nanomaterials and other synthetic methods such as ligand exchange and microfluidic processes.

Silicon (Si) anodes have long been recognized to significantly improve the energy density and fast-charging capability of lithium-ion batteries (LIBs). However, the implementation of these anodes in commercial LIB cells has progressed incrementally due to the immense volume change of Si across its full state-of-charge (SOC) range. Here, we report an anode-tailored full-cell design (ATFD), which incorporates micrometer-sized silicon (μ-Si) alone, for operation over a limited, prespecified SOC range identified as 30-70%. This range allows homogeneous (de)lithiation throughout the electrode, accompanied by an acceptable level of volume change. The ATFD-based cell exhibits 21.3% higher gravimetric energy density than that of its graphite-based counterpart in a commercial 18650 cylindrical cell and 84.6% capacity retention after 500 cycles even at a fast-charging rate of 3 C. This study indicates that the partial, intermediate SOC operation of the μ-Si anode can markedly increase the energy density and boost the fast-charging capability of a LIB cell, a challenging task in traditional cell engineering., Competing Interests: Competing interests statement:T.L. and J.W.C. have filed a Korean patent derived from this work.

This paper introduces a novel approach to estimating censored quantile regression using inverse probability of censoring weighted (IPCW) methodology, specifically tailored for data sets featuring partially interval-censored data. Such data sets, often encountered in HIV/AIDS and cancer biomedical research, may include doubly censored (DC) and partly interval-censored (PIC) endpoints. DC responses involve either left-censoring or right-censoring alongside some exact failure time observations, while PIC responses are subject to interval-censoring. Despite the existence of complex estimating techniques for interval-censored quantile regression, we propose a simple and intuitive IPCW-based method, easily implementable by assigning suitable inverse-probability weights to subjects with exact failure time observations. The resulting estimator exhibits asymptotic properties, such as uniform consistency and weak convergence, and we explore an augmented-IPCW (AIPCW) approach to enhance efficiency. In addition, our method can be adapted for multivariate partially interval-censored data. Simulation studies demonstrate the new procedure's strong finite-sample performance. We illustrate the practical application of our approach through an analysis of progression-free survival endpoints in a phase III clinical trial focusing on metastatic colorectal cancer., (© 2024 The Author(s). Biometrical Journal published by Wiley‐VCH GmbH.)

Hematopoietic cell transplantation (HCT) is a promising treatment for hematologic malignancies, but intensive conditioning leads to immunosuppression and susceptibility to healthcare-associated infections (HAI). Despite standard prevention measures, bloodstream infections (BSI) impact a significant percentage of immunocompromised HCT patients. Incidence of BSI can be mitigated by chlorhexidine gluconate (CHG) bathing-an underutilized infection-prevention strategy. Gaining HCT recipients' perceptions on CHG bathing can inform strategies to improve adherence and enhance patient outcomes., Purpose: This study explored patients' perceived facilitators, barriers, and education/knowledge related to CHG bathing and thus addresses the gap in implementation for immunocompromised HCT patients., Methods: This study used a qualitative description approach to explore patients' perceived facilitators, barriers, and knowledge of CHG bathing. Fourteen HCT recipients (mean 51 ± 16 years) completed semi-structured interviews. Data were analyzed using a rapid qualitative analysis approach to identify themes., Results: Participants identified facilitators to using CHG wipes including ease of use, comfort, and staff assistance, along with barriers including wait time, discomfort, and physical challenges. Patient education themes encompassed patient understanding of CHG purpose, perceived ease in learning/application, inconsistent instruction, and inconsistent procedures., Conclusion: CHG bathing is a valuable infection prevention strategy for HCT patients. Participants' perspectives highlight the importance of addressing practical challenges and improving education to enhance adherence. This study contributes insights from HCT recipients, emphasizing the need for patient-centered interventions to reduce HAI and improve overall patient care., Competing Interests: Declarations. Ethics approval: All procedures performed in this study were in accordance with the ethical standards of the institution and the Declaration of Helsinki. The study protocol was approved by Duke University's Institutional Review Board (Protocol # Pro00093701). Consent to participate: Verbal informed consent was obtained prior to the interview. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Irgarol 1051 is an herbicide extensively utilized in antifouling paint due to its ability to inhibit photosynthesis. Irgarol and its photodegradation products are highly persistent in waters and sediments, although they are present in low concentrations. However, our understanding of the harmful effects of Irgarol on non-target organisms remains limited. In this study, we assessed the effects of acute (24 h) and chronic (14 days across three generations) exposure to different concentrations (including the 1/10 NOEC, NOEC, and 1/10 LC50 calculated from the 24-h acute toxicity test) of Irgarol using the water flea Moina macrocopa. Acute exposure to 1/10 LC50 significantly decreased survival, feeding rate, thoracic limb activity, heart rate, and acetylcholinesterase activity. Elevated levels of intracellular reactive oxygen species and malondialdehyde, along with a significant increase in catalase and superoxide dismutase activity, suggested the induction of oxidative stress in response to 1/10 LC50. An initial boost in glutathione level and the enzymatic activities of glutathione peroxidase and glutathione reductase, followed by a plunge, implies some compromise in the antioxidant defense system. Upon chronic exposure to the NOEC value, both generations F1 and F2 displayed a significant decrease in survival rate, body length, number of neonates per brood, and delayed sexual maturation, suggesting maternal transfer of potential damage through generations. Taken together, Irgarol induced acute toxicity through physiological and cholinergic damage, accompanied by the induction of oxidative stress, in the water flea. Even its sub-lethal concentrations can induce detrimental effects across generations when consistently exposed., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Slim cameras are essential in state-of-the-art consumer electronics such as smartphones or augmented/virtual reality devices. However, reducing the camera thickness faces challenges primarily due to the thick lens systems. Current lens systems, composed of stacked refractive lenses, are fundamentally constrained from becoming thinner due to the presence of empty spaces between lenses and the excessive volume of each lens. Here, we present a lens system using metasurface folded optics to overcome these pervasive issues. In our design, metasurfaces are arranged horizontally on a glass wafer and direct light along multifolded paths inside the substrate. This approach achieves an ultra-slim lens system with a thickness of 0.7 millimeters and 2× thinner relative to the EFL, thereby overcoming the inherent limitations of conventional optical platforms. It delivers quasi-diffraction-limited imaging quality with a 10° field of view and an f number of 4 at an operational wavelength of 852 nanometers. Our findings provide a compelling platform for compact cameras using folded nano-optics.

This study investigated the effects of acupuncture and warm acupuncture on the expression and mechanism of the AMP-activated protein kinase ( AMPK ) signalling pathway associated with lipid accumulation in the liver tissue of rats with metabolic dysfunction-associated fatty liver disease (MAFLD) induced by a high-fat diet. Sprague-Dawley rats were categorised into four groups: control (CON), untreated MAFLD (MAFLD), and two MAFLD groups treated with acupuncture (ACU) and warm acupuncture (WA). The treatment groups underwent 16 application sessions over 8 weeks at the SP9 and BL18 acupoints. We measured the expression levels of AMPK , sterol regulatory element-binding protein1 ( SREBP1 ), acetyl-coenzyme A carboxylase ( ACC ), peroxisome proliferator-activated receptorα ( PPARα ), carnitine palmitoyltransferase1 ( CPT1 ), and CPT2 . AMPK was activated in both ACU and WA groups. WA downregulated both SREBP1 and ACC expression at the protein level, whereas the acupuncture treatment downregulated SREBP1 expression. Additionally, WA selectively induced the activation of signalling pathways related to AMPK, PPARα, CPT1 , and CPT2 at the mRNA level. Histological observations confirmed that fat accumulation was reduced in both the ACU and the WA groups compared to the MAFLD group. The WA treatment-promoted amelioration of HFD-induced MAFLD may be related to the activation of the AMPK/SREBP1/ACC pathway in the liver.

Rheumatoid arthritis is a debilitating inflammatory condition which has a high disease burden. While there is emerging evidence that certain foods and diets could have anti-inflammatory properties and there are published 'anti-inflammatory' diets, there is very little understanding of patient beliefs and perceptions about the impact of diet on symptom management or attitudes to particular dietary interventions. This scoping review aims to summarize the existing literature around the beliefs that patients with rheumatoid arthritis hold regarding the impact of diet on disease activity and joint pain. It also examines the current state of evidence regarding the impact of specific dietary interventions on patient reported and objective parameters of RA disease activity. A search was conducted across seven databases for studies which included reporting on dietary beliefs related to disease management or investigations on the effect of particular diets on disease activity or joint pain. Articles were excluded if they examined extracted compounds or individual dietary supplements. Included studies were synthesized narratively. We retrieved 25,585 papers from which 68 were included in this review: 7 assessed dietary beliefs, 61 explored dietary interventions. The available literature on patient beliefs has been largely limited to quantitative studies with limited qualitative exploration. The Mediterranean, fasting and vegan diets appear to have the most benefit with regards to rheumatoid arthritis outcomes for patients. Research which examines RA patient's beliefs and attitudes about the impact of diet on their RA symptoms and disease is currently lacking., (© 2024. The Author(s).)

Background: Interest in the role of employability in student-dietitian transitions is increasing. However, little is known about the cross-cultural transition-to-work experience of Australian-trained dietetic graduates of international backgrounds, as well as strategies to optimise work-readiness. The present study aimed to explore graduates' career narratives and identify employability capitals that enabled successful transitions to work., Methods: A qualitative interpretive approach was employed via a cultural lens. Eighteen participants from five Asian countries who had graduated from an Australian university within 3-15 years, with work experience in Australia or in their respective home countries, took part in in-depth interviews. Thematic analysis was performed, guided by the graduate capitals based approach., Results: Transition-to-work was dynamic and non-linear; four themes and 12 subthemes identified: (1) upon graduation, participants felt ambivalent about their decision to either stay in Australia or return home, influenced by graduate visa restrictions, and individual perceptions of their ability to mobilise cultural strengths to gain employment; (2) to get a foot in the door, participants demonstrated resilience, embraced uncertainty and utilised social networks to increase employment opportunities in Australia and their home countries; (3) regardless of which country they worked, graduates reported struggling with their cross-cultural identities in the workplace; and (4) eventually, these graduates appreciated their ethnic capital, thrived in their work and extended a helping hand to their junior cross-cultural dietitians., Conclusions: Initiatives facilitating connections to the host country and supporting cultural and ethnic capital development, along with ongoing research reviewing employability capital applications, will benefit cross-cultural dietetic graduates and the communities they potentially will serve., (© 2024 The Author(s). Journal of Human Nutrition and Dietetics published by John Wiley & Sons Ltd on behalf of British Dietetic Association.)

The bovine embryo production industry has seen significant growth over the past two decades, particularly in the production of in vitro produced embryos. This growth, driven by advancements in cryopreservation, in vitro culture mediums, ovum pick-up (OPU) procedures, ultrasonography devices, and embryo transfer (ET) has been notable. Particularly, ET is crucial for disseminating high genetic merit and amplifying foreign breeds by importing frozen embryos. This retrospective study aimed to assess factors affecting conception per embryo transfer (CPET) in Holstein-Friesian cattle in South Korea from October 2008 to July 2022. We evaluated type of embryo breed, type of embryo production (fresh and frozen; in vitro and in vivo production), recipient conditions including estrus type, corpus luteum quality, parity (nulliparous heifers, primiparous, and multiparous cows), and the daily mean temperature-humidity index (THI) as an index for heat stress. Type of embryo breed and estrus had no significant impact on CPET. However, we observed higher CPET in recipients with good quality corpus luteum, nulliparous heifers, and surrogates receiving fresh in vitro and frozen in vivo embryos. Importantly, CPET was not adversely affected by mild heat stress conditions (up to daily mean THI 76), indicating that using frozen in vivo embryos produced by multiple ovulation embryo transfer and fresh in vitro embryos by OPU-ET can help alleviate the subfertility issues in dairy cattle caused by global warming in Korea., (Copyright © 2024. Published by Elsevier Inc.)

Primary retroperitoneal mucinous cystic tumors (PRMCT) are divided into 3 groups: benign, borderline malignancy, and malignant. We report a rare case of benign retroperitoneal mucinous cystadenoma of a 59-year-old Caucasian female who presented to our clinic with moderate intermittent left upper quadrant abdominal pain for several months, accompanied by early satiety, and unintentional weight loss of 10 pounds. An abdominal contrast-enhanced computed tomography (CT) scan indicated the presence of a 6.5 × 8.8 cm multilobulated mass in the left upper quadrant, characterized by a homogenous appearance with smooth margins. Upper endoscopic ultrasound and fine needle aspiration were performed. Cytology and histology results yielded rare inflammatory cells and debris with no cytological evidence of malignancy. The case was discussed at the hepatopancreatobiliary conference; the patient underwent a robotic resection of the mass with a gastric rim. Primary retroperitoneal mucinous cystadenomas are commonly managed by complete surgical excision. Robotic excision presents an alternative approach for handling this uncommon neoplastic lesion., (© 2024 The Authors. Published by Elsevier Inc. on behalf of University of Washington.)

Background: Whether use of SGLT2 inhibitors reduces the risk of cardiovascular and kidney events in people who contracted SARS-CoV-2 infection is not clear., Methods: We used the healthcare databases of the United States Department of Veterans Affairs to build a cohort of 107,776 participants on antihyperglycemic therapy and had SARS-CoV-2 infection between March 01, 2020 and June 10, 2023. Within them, 11,588 used SGLT2 inhibitors and 96,188 used other antihyperglycemics. We examined the risks of major adverse cardiovascular events (MACE)-a composite of death, myocardial infarction and stroke, and major adverse kidney events (MAKE)-a composite of death, eGFR decline > 50%, and end stage kidney disease after balancing baseline characteristics between groups through inverse probability weighting. Survival analyses were conducted to generate hazard ratio (HR) and absolute risk reduction per 100 person-years (ARR)., Results: Over a median follow up of 1.57 (IQR: 1.05-2.49) years, compared to the control group, SGLT2 inhibitors use is associated with reduced risk of MACE (HR 0.82 (0.77, 0.88), ARR 1.73 (1.21, 2.25)) and reduced risk of MAKE (HR 0.75 (0.71, 0.80), ARR 2.62 (2.13, 3.11)). Compared to the control group, SGLT2 inhibitors use is associated with reduced risk of the secondary outcomes of hospitalization (HR 0.94 (0.90, 0.98), ARR 1.06 (1.36, 1.76)), anemia (HR 0.71 (0.65, 0.76), ARR 2.43 (1.95, 2.90)), and acute kidney injury (HR 0.84 (0.79, 0.89), ARR 1.86 (1.29, 2.42))., Conclusions: Among people with SARS-CoV-2 infection on antihyperglycemic therapy, compared to those on other antihyperglycemics, those on SGLT2 inhibitors have less risk of adverse cardiovascular and kidney outcomes., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

In this paper, a novel thermo-optic metagrating based on phase-change material (vanadium dioxide, VO 2 ) is proposed for broadband, polarization-independent, and non-dispersive transmission modulation at the telecommunication wavelengths. In the pursuit of concurrent attainment of multiple performance objectives, nanostructured VO 2 metagratings are optimized numerically using inverse design algorithms. Notably, adjoint optimization pertaining to both phases of VO 2 facilitates better modulation capabilities within free-form shaped VO 2 metagratings compared to shape-optimized methods with predetermined designs. It is verified that the free-form metagrating modulator achieves broad bandwidth (∼300 nm), large modulation depth (>0.8) and non-dispersive transmittance (∼0.2), and polarization independent operation. The design ensures polarization-independence, verified through both simulations and experiments. Experimental validation included fabricating VO 2 metagratings and measuring their performance across varying temperatures. The results demonstrate agreement with theoretical predictions, highlighting the device's potential for applications in next-generation spatial light modulators, optical routers, and three-dimensional optical scanning sensors. This study underscores the promising capabilities of VO 2 -based metagratings in dynamic optical modulation and broadband telecommunication applications.

Deflectors are essential for modulating beam direction in optical systems but often face form factor issues or chromatic aberration with conventional optical elements, such as prisms, mirrors, and diffractive/holographic optical elements. Despite recent efforts to address such issues using metasurfaces, their practicality remains limited due to operation wavelengths in the near-infrared or the fabrication difficulties inherent in the multilayer scheme. Here, we propose a novel single-layer metasurface achieving multiwavelength chromatic aberration-free deflection across the visible spectrum by employing the robust freeform design strategy to simplify the fabrication process. By properly selecting diffraction orders for red, green, and blue wavelengths to achieve identical wavelength-diffraction-order products, the metasurface deflects light at a consistent angle of 41.3° with a high efficiency. The coupled Bloch mode analysis explains the physical properties, and experimental fabrication and characterization confirm its effectiveness. This approach holds potential for various applications such as AR/VR, digital cameras, and high-quality optical systems.

A novel green-absorbing organic molecule featuring dual intramolecular chalcogen bonds is synthesized and characterized. This molecule incorporates two such bonds: one between a tellurium atom and the oxygen atom of a carbonyl moiety, and the other between the tellurium atom and the adjacent nitrogen atom within a pyridine moiety. The molecule, featuring dual intramolecular chalcogen bonds exhibits a narrow absorption spectrum and elevated absorption coefficients, closely aligned with a resonance parameter of approximately 0.5. This behavior is due to its cyanine-like characteristics and favorable electrical properties, which are a direct result of its rigid, planar molecular structure. Therefore, this organic molecule forming dual intramolecular chalcogen bonds achieves superior optoelectronic performance in green-selective photodetectors, boasting an external quantum efficiency of over 65% and a full-width at half maximum of less than 95 nm while maintaining the performance after 1000 h of heating aging at 85 °C. Such organic photodetectors are poised to enhance stacked organic photodetector-on-silicon hybrid image sensors, paving the way for the next-generation of high-resolution and high-sensitivity image sensors., (© 2024 The Author(s). Small published by Wiley‐VCH GmbH.)