A negative photoconductivity photodetector based on two-dimensional Nb3Cl8.

Negative photoconductivity (NPC)-based photodetectors offer a new direction for energy-efficient photodetection technologies, featuring low energy consumption and high responsivity. Two-dimensional (2D) materials are particularly promising for implementing NPC due to their large surface area, abundant surface states, and tunable bandgap properties. In this context, 2D Nb3Cl8, with its unique kagome lattice structure and broad absorption spectrum, has attracted considerable interest. Notably, metal halides such as Nb3Cl8 demonstrate significant potential as NPC materials due to their low anionic and cationic bonding strength, which allows for the formation of vacancy defects with high probability. However, the NPC characteristics of Nb3Cl8 have not been thoroughly investigated. In this study, we fabricated field-effect transistors (FETs) using Nb3Cl8 single crystals synthesized via chemical vapor transport (CVT). These devices exhibited an electron mobility of 4.24 × 10-3 cm2 V-1 s-1 and a high Ion/Ioff ratio of 1.42 × 104. Notably, Nb3Cl8-based photodetectors demonstrated consistent NPC behavior across a wide wavelength range of 400-1050 nm, with a high responsivity of 156.82 mA W-1 at 400 nm. We propose that the trapping effect due to defect levels within the bandgap is the primary cause of this NPC phenomenon. The present findings reveal the unique photodetector properties of Nb3Cl8 and highlight its promise in energy-efficient photodetectors and various optoelectronic applications.

Size-dependent toxic interaction between polystyrene beads and mercury on the mercury accumulation and multixenobiotic resistance (MXR) of brackish water flea Diaphanosoma celebensis.

Due to their worldwide distribution and persistence, mercury (Hg), and nano- and microplastics (NMPs) pose major threats to global ocean ecosystems. Hg and NMPs co-exist in the ocean and can interact with each other. However, information on the toxicity of this interaction to marine biota remains limited. Thus, we investigated the toxicological interaction between HgCl2 (Hg) and NMPs by studying the influence of different sizes of polystyrene beads (0.05-, 0.5-, and 6-µm) on Hg accumulation in the brackish water flea Diaphanosoma celebensis. The Hg adsorption capacity of NPs (0.05-µm) was higher than that of MPs (0.5- and 6-µm). Only the group co-exposed to both Hg and NPs showed increased Hg content in D. celebensis. Multixenobiotic resistance (MXR) activity and transcriptional modulation of transporter genes (ABCBs and ABCCs) were decreased by NMP exposure, particularly by NPs, suggesting MXR disruption by NPs. However, only the activity of multidrug resistance-associated proteins (MRPs; ABCCs) increased with Hg exposure and decreased upon NP+Hg co-exposure, indicating an important role of ABCC in Hg efflux. Furthermore, in vivo toxicity tests showed a synergistic toxic interaction between Hg and NPs on the reproduction of D. celebensis. Our findings suggest that NPs have the potential to enhance the toxicity of Hg, increasing Hg accumulation not only by serving Hg as a carrier but also by disrupting MXR.

Hair Growth Promoting Effects of Solubilized Sturgeon Oil and Its Correlation with the Gut Microbiome.

Androgenetic alopecia is a common disease that occurs in both men and women. Several approved medications have been used to treat this condition, but they are associated with certain side effects. Therefore, use of extracts derived from natural products, such as Siberian sturgeon (Acipenser baerii), and the regulation of the gut microbiota have become important topics of research. Sturgeon is known for its high nutritional value and anti-inflammatory properties; however, its effects on androgenetic alopecia and gut microbiota remain uncharacterized. Here, we aimed to investigate whether solubilized sturgeon oil (SSO) promotes hair growth and regulates the gut microbiome. C57BL/6 mice were divided into four groups. Three groups received topical applications of distilled water, SSO, or minoxidil, and one group was orally administered SSO. Each treatment was administered over 4 weeks. Histopathological analysis revealed a significant increase in follicle number (p < 0.001) and follicle diameter (p < 0.05). Immunohistochemical analysis revealed upregulation of ß-catenin and ERK-1, markers involved in hair growth-promoting pathways. Furthermore, microbiome analysis revealed that the reduced gut microbiota was negatively correlated with these markers. Our findings indicate that oral administration of SSO promotes hair growth and regulates the abundance of hair growth-promoting gut microbiota.

Augmented Extraction Efficiency of a Hot D Exciton in MoS2 via Intervalley Scattering.

Prolonging hot carrier cooling, a crucial factor in optoelectronic applications, including hot carrier photovoltaics, presents a significant challenge. High-energy band-nesting excitons within parallel bands offer a promising and underexplored avenue for addressing this issue. Here, we exploit an exceptional D exciton cooling prolongation of 2 to 3 orders of magnitude compared to sub-picosecond in typical transition metal dichalcogenides (TMDs) owing to the complex Coulomb environment and the sequential and mismatch-valley relaxation. Simultaneously, the intervalley scattering upconversion of band-edge excitons with the slow D exciton formation in the metastable Γ valley/hill also reduces the cooling rate. We successfully extract D and C excitons as hot carriers through integrating with various thicknesses of TiOx, achieving the highest efficiency of 98% and 85% at a Ti thickness of 2 nm. Our findings highlight the potential of band-nesting excitons for extending hot carrier cooling time, paving the way for advancements in hot carrier-based optoelectronic devices.

Coronavirus nucleocapsid-based vaccine provides partial protection against hetero-species coronavirus in murine models.

Most coronavirus vaccines focus on the spike (S) antigen, but the frequent mutations in S raise concerns about the vaccine efficacy against new variants. Although additional antigens with conserved sequences are have been tested, the extent to which these vaccines can provide immunity against different coronavirus species remains unclear. In this study, we assessed the potential of nucleocapsid (N) as a coronavirus vaccine antigen. Immunization with MERS-CoV N induced robust immune responses, providing significant protection against MERS-CoV. Notably, MERS-CoV N elicited cross-reactive T cell responses to SARS-CoV-2 N and significantly reduced lung inflammation following a SARS-CoV-2 challenge in the transient hACE2 mouse model. However, in K18-hACE transgenic mice, the vaccine showed limited protection. Collectively, our findings suggest that coronavirus N can be an effective vaccine antigen against homologous viruses, but its efficacy may vary across different coronaviruses, highlighting the need for further research on pan-coronavirus vaccines using conserved antigens.

Beta-arrestin 1 mediated Src activation via Src SH3 domain revealed by cryo-electron microscopy.

Beta-arrestins (ßarrs) are key regulators and transducers of G-protein coupled receptor signaling; however, little is known of how ßarrs communicate with their downstream effectors. Here, we use cryo-electron microscopy to elucidate how ßarr1 recruits and activates non-receptor tyrosine kinase Src. ßarr1 binds Src SH3 domain via two distinct sites: a polyproline site in the N-domain and a non-proline site in the central crest region. At both sites ßarr1 interacts with the aromatic surface of SH3 which is critical for Src autoinhibition, suggesting that ßarr1 activates Src by SH3 domain displacement. Binding of SH3 to the central crest region induces structural rearrangements in the ß-strand V, finger, and middle loops of ßarr1 and interferes with ßarr1 coupling to the receptor core potentially impacting receptor desensitization and downstream signaling.

Developing a list of Alert Alien Species in South Korea.

Along with transportation development, climate change and socio-economic changes, invasive alien species (IAS) are causing a significant decline in biodiversity around the world. Internationally, policies for pre-invasion management of IAS are being emphasised to minimise damage from biological invasions. In South Korea, through the 2nd Alien Species Management Plan (2019-2023), IAS that are not yet present in the country but are likely to be introduced are designated as Alert Alien Species (AAS). In this study, the overall process of AAS designation is summarised and improvements to the current system are presented. To select AAS, an invasive alien species database (IASD) of 8,456 species was built by integrating the IAS lists from many countries. Amongst them, 1,534 species, included in IASD at genus, family and order level, were excluded and 3,298 species confirmed to have been introduced to South Korea were excluded from the AAS candidate species. After the creation and review of species profiles by experts, 150 species were finally designated as AAS in 2023. The AAS discovery process needs to reflect international trends of IAS and be continuously supplemented through policy research of other countries. In addition, the IAS management system in South Korea, in which various ministries play their own roles with sufficient data sharing, should be systematically linked from introduction to control of IAS.

Coupling photocatalytic CO2 reduction and CH3OH oxidation for selective dimethoxymethane production.

Currently, conventional dimethoxymethane synthesis methods are environmentally unfriendly. Here, we report a photo-redox catalysis system to generate dimethoxymethane using a silver and tungsten co-modified blue titanium dioxide catalyst (Ag.W-BTO) by coupling CO2 reduction and CH3OH oxidation under mild conditions. The Ag.W-BTO structure and its electron and hole transfer are comprehensively investigated by combining advanced characterizations and theoretical studies. Strikingly, Ag.W-BTO achieve a record photocatalytic activity of 5702.49 µmol g-1 with 92.08% dimethoxymethane selectivity in 9 h of ultraviolet-visible irradiation without sacrificial agents. Systematic isotope labeling experiments, in-situ diffuse reflectance infrared Fourier-transform analysis, and theoretical calculations reveal that the Ag and W species respectively catalyze CO2 conversion to *CH2O and CH3OH oxidation to *CH3O. Subsequently, an asymmetric carbon-oxygen coupling process between these two crucial intermediates produces dimethoxymethane. This work presents a CO2 photocatalytic reduction system for multi-carbon production to meet the objectives of sustainable economic development and carbon neutrality.

Role of the V2R-ßarrestin-Gßγ complex in promoting G protein translocation to endosomes.

Classically, G protein-coupled receptors (GPCRs) promote signaling at the plasma membrane through activation of heterotrimeric Gαßγ proteins, followed by the recruitment of GPCR kinases and ßarrestin (ßarr) to initiate receptor desensitization and internalization. However, studies demonstrated that some GPCRs continue to signal from internalized compartments, with distinct cellular responses. Both ßarr and Gßγ contribute to such non-canonical endosomal G protein signaling, but their specific roles and contributions remain poorly understood. Here, we demonstrate that the vasopressin V2 receptor (V2R)-ßarr complex scaffolds Gßγ at the plasma membrane through a direct interaction with ßarr, enabling its transport to endosomes. Gßγ subsequently potentiates Gαs endosomal translocation, presumably to regenerate an endosomal pool of heterotrimeric Gs. This work shines light on the mechanism underlying G protein subunits translocation from the plasma membrane to the endosomes and provides a basis for understanding the role of ßarr in mediating sustained G protein signaling.

Effects of hydrologic regimes on the loading and spatiotemporal variation of mercury in the microtidal river estuary.

The potential effect of hydrological conditions on distribution and loadings of Hg species was investigated in the microtidal Hyeongsan River Estuary (HRE). Dissolved Hg (DHg) and dissolved methylmercury (DMeHg) from the creek receiving industrial wastes were effectively settled to sediment during the post-typhoon period, while persistent input from the Hg-contaminated creek without settling was observed during the dry periods. The event-based mean approach was applied to explore the hydrological effects on the annual flux of Hg. The largest inputs of DHg and particulate Hg (PHg) were found in the Hg-contaminated creek, and DHg input was higher in the dry than wet periods whereas PHg input was higher in the wet than dry periods. In sediment, Hg and MeHg concentrations decreased after the typhoon, attributed to erosion of surface sediments. Overall, the HRE serves as an effective sink of Hg that reduces the degree of Hg contamination in coastal water.

The Life Functioning Scale: a Measurement Tool Developed to Assess the Physical Functioning Abilities of Community-Dwelling Adults Aged 50 Years or Older.

Background: This study aimed to develop an instrument for assessing physical functioning among adults aged 50 years or older living in the community. Methods: Based on a review of various national health surveys and cohort studies, a 144-item bank was constructed for assessing physical functioning. Focus group interviews were conducted among adults aged 50 years or older to investigate their level of understanding of 60 selected items, followed by a pretest of the items on a nationally representative sample (n = 508). The final 25-item questionnaire was tested on an independent sample (n = 259) for validity and reliability based on classical test and item response theories. Predictive validity at the 6-month follow-up was tested in a separate sample (n = 263). Results: The newly developed Life Functioning (LF) scale assessed the dimensions of functional limitations, disabilities, and social activities. The scale satisfied a one-dimensionality assumption with good item fit and demonstrated criterion validity, construct validity, high internal consistency (Cronbach's alpha = 0.93), and test-retest reliability (intra-class correlation coefficient = 0.84; 95% CI, 0.76-0.89). The LF scale comprised 25 items with a total score ranging from 0 to 100. Higher scores indicated higher levels of functioning. The LF score was significantly associated with the physical functioning score at 6 months. Conclusion: The LF scale was developed to assess the physical functioning of people in their late midlife or older. Future studies should test the instrument on a national sample and evaluate its application in diverse population subgroups.

Fluorinated Organic Cations Derived Chiral 2D Perovskite Enabling Enhanced Spin-Dependent Oxygen Evolution Reaction.

Chirality-induced spin selectivity observed in chiral 2D organic-inorganic hybrid perovskite holds promise to achieve spin-dependent electrochemistry. However, conventional chiral 2D perovskites suffer from low conductivity and hygroscopicity, limiting electrochemical performance and operational stability. Here, a cutting-edge material design is introduced to develop a stable and efficient chiral perovskite-based spin polarizer by employing fluorinated chiral cation. The fluorination approach effectively promotes the charge carrier transport along the out-of-plane direction by mitigating the dielectric confinement effect within the multi-quantum well-structured 2D perovskite. Integrating the fluorinated cation incorporated spin polarizer with BiVO4 photoanode considerably boosts the photocurrent density while reducing overpotential through a spin-dependent oxygen evolution reaction. Furthermore, the hydrophobic nature of fluorine in spin polarizer endows operational stability to the photoanode, extending the durability by 280% as compared to the device with non-fluorinated spin polarizer.

Particulate Matter-Induced Neurotoxicity: Unveiling the Role of NOX4-Mediated ROS Production and Mitochondrial Dysfunction in Neuronal Apoptosis.

Urban air pollution, a significant environmental hazard, is linked to adverse health outcomes and increased mortality across various diseases. This study investigates the neurotoxic effects of particulate matter (PM), specifically PM2.5 and PM10, by examining their role in inducing oxidative stress and subsequent neuronal cell death. We highlight the novel finding that PM increases mitochondrial ROS production via stimulating NOX4 activity, not through its expression level in Neuro-2A cells. Additionally, PMs provoke ROS production via increasing the expression and activity of NOX2 in SH-SY5Y human neuroblastoma cells, implying differential regulation of NOX proteins. This increase in mitochondrial ROS triggers the opening of the mitochondrial permeability transition pore (mPTP), leading to apoptosis through key mediators, including caspase3, BAX, and Bcl2. Notably, the voltage-dependent anion-selective channel 1 (VDAC1) increases at 1 µg/mL of PM2.5, while PM10 triggers an increase from 10 µg/mL. At the same concentration (100 µg/mL), PM2.5 causes 1.4 times higher ROS production and 2.4 times higher NOX4 activity than PM10. The cytotoxic effects induced by PMs were alleviated by NOX inhibitors GKT137831 and Apocynin. In SH-SY5Y cells, both PM types increase ROS and NOX2 levels, leading to cell death, which Apocynin rescues. Variability in NADPH oxidase sources underscores the complexity of PM-induced neurotoxicity. Our findings highlight NOX4-driven ROS and mitochondrial dysfunction, suggesting a potential therapeutic approach for mitigating PM-induced neurotoxicity.

Strategies to Enrich Electrochemical Sensing Data with Analytical Relevance for Machine Learning Applications: A Focused Review.

In this review, recent advances regarding the integration of machine learning into electrochemical analysis are overviewed, focusing on the strategies to increase the analytical context of electrochemical data for enhanced machine learning applications. While information-rich electrochemical data offer great potential for machine learning applications, limitations arise when sensors struggle to identify or quantitatively detect target substances in a complex matrix of non-target substances. Advanced machine learning techniques are crucial, but equally important is the development of methods to ensure that electrochemical systems can generate data with reasonable variations across different targets or the different concentrations of a single target. We discuss five strategies developed for building such electrochemical systems, employed in the steps of preparing sensing electrodes, recording signals, and analyzing data. In addition, we explore approaches for acquiring and augmenting the datasets used to train and validate machine learning models. Through these insights, we aim to inspire researchers to fully leverage the potential of machine learning in electroanalytical science.

Polyhexamethylene guanidine phosphate induces pyroptosis via reactive oxygen species-regulated mitochondrial dysfunction in bronchial epithelial cells.

Pyroptosis is a form of programmed cell death characterized by gasdermin (GSDM)-mediated pore formation in the cell membrane, resulting in the release of pro-inflammatory cytokines and cellular lysis. Increasing evidence has shown that pyroptosis is responsible for the progression of various pulmonary disorders. The inhalation of polyhexamethylene guanidine (PHMG) causes severe lung inflammation and pulmonary toxicity; however, the underlying mechanisms are unknown. Therefore, in this study, we investigate the role of pyroptosis in PHMG-induced pulmonary toxicity. We exposed bronchial epithelial cells, BEAS-2B, to PHMG phosphate (PHMG-p) and evaluated cell death type, reactive oxygen species (ROS) levels, and relative expression levels of pyroptosis-related proteins. Our data revealed that PHMG-p reduced viability and induced morphological alterations in BEAS-2B cells. Exposure to PHMG-p induced excessive accumulation of mitochondrial ROS (mtROS) in BEAS-2B cells. PHMG-p activated caspase-dependent apoptosis as well as NLRP3/caspase-1/GSDMD-mediated- and caspase-3/GSDME-mediated pyroptosis through mitochondrial oxidative stress in BEAS-2B cells. Notably, PHMG-p reduced mitochondrial respiratory function and induced the translocation of Bax and cleaved GSDM into the mitochondria, leading to mitochondrial dysfunction. Our results enhanced our understanding of PHMG-p-induced lung toxicity by demonstrating that PHMG-p induces pyroptosis via mtROS-induced mitochondrial dysfunction in bronchial epithelial cells.

Antibodies expand the scope of angiotensin receptor pharmacology.

G-protein-coupled receptors (GPCRs) are key regulators of human physiology and are the targets of many small-molecule research compounds and therapeutic drugs. While most of these ligands bind to their target GPCR with high affinity, selectivity is often limited at the receptor, tissue and cellular levels. Antibodies have the potential to address these limitations but their properties as GPCR ligands remain poorly characterized. Here, using protein engineering, pharmacological assays and structural studies, we develop maternally selective heavy-chain-only antibody ('nanobody') antagonists against the angiotensin II type I receptor and uncover the unusual molecular basis of their receptor antagonism. We further show that our nanobodies can simultaneously bind to angiotensin II type I receptor with specific small-molecule antagonists and demonstrate that ligand selectivity can be readily tuned. Our work illustrates that antibody fragments can exhibit rich and evolvable pharmacology, attesting to their potential as next-generation GPCR modulators.

Spectrally Resolved Exciton Polarizability for Understanding Charge Generation in Organic Bulk Hetero-Junction Diodes.

Despite decades of research, the dominant charge generation mechanism in organic bulk heterojunction (BHJ) devices is not completely understood. While the local dielectric environments of the photoexcited molecules are important for exciton dissociation, conventional characterizations cannot separately measure the polarizability of electron-donor and electron-acceptor, respectively, in their blends, making it difficult to decipher the spectrally different charge generation efficiencies in organic BHJ devices. Here, by spectrally resolved electroabsorption spectroscopy, we report extraction of the excited state polarizability for individual donors and acceptors in a series of organic blend films. Regardless of the donor and acceptor, we discovered that larger exciton polarizability is linked to larger π-π coherence length and faster charge transfer across the heterojunction, which fundamentally explains the origin of the higher charge generation efficiency near 100% in the BHJ photodiodes. We also show that the molecular packing of the donor and acceptor influence each other, resulting in a synergetic enhancement in the exciton polarizability.

A Practical Algorithm for Integrating Skincare to Improve Patient Outcomes and Satisfaction With Energy-Based Dermatologic Procedures.

BACKGROUND: Medical aesthetic procedures for facial antiaging with laser and energy-based devices (EBDs) are rapidly increasing, but standards integrating skincare before, during, and after these treatments are lacking. The algorithm for integrated skin care for facial antiaging treatment with EBDs aims to stimulate healing, reduce downtime, and improve comfort and treatment outcomes. METHODS: A panel of 8 global physicians employed a modified Delphi method and reached a consensus on the algorithm integrating skincare based on the best available evidence, the panel's clinical experience, and opinions. RESULTS: The algorithm has a pretreatment (starts 2 - 4 weeks before the procedure) and treatment (day of treatment) section, followed by care after the procedure (0 - 7 days) and follow-up care (1 - 4 weeks after the procedure or ongoing). Applying a broad-spectrum sunscreen with an SPF 50 or higher, combined with protective measures such as wearing a wide-brimmed hat and sunglasses, is recommended to protect the face from sun exposure. Dyschromia is a significant concern for those with skin of color (SOC). Clinicians may recommend skincare using a gentle cleanser and moisturizer containing vitamins C and E, retinoid, or other ingredients such as niacinamide, kojic acid, licorice root extract, azelaic acid, and tranexamic acid, depending on the patient's facial skin condition. CONCLUSION: Medical aesthetic procedures for facial antiaging with EBDs integrating skincare or topical treatments may improve outcomes and patient satisfaction. Topical antioxidants and free radical quenchers can combat photodamage and may offer a safe alternative to topical hydroquinone.  J Drugs Dermatol. 2024;23(5):353-359.     doi:10.36849/JDD.8092.