Exploring the relationship between super-leadership, self-leadership, and exercise commitment in university Taekwondo teams.

Introduction: Promoting super-leadership is crucial for the sustainable growth of college sport teams, especially as teams are experiencing a noticeable shift towards a more horizontal dynamic, where athletes themselves are emerging as leaders. However, there is a lack of research on the effectiveness of super-leadership and its possible outcomes in the context of collegiate Taekwondo teams. Methods: This study aims to investigate the impact of super-leadership on athletes' self-leadership and exercise commitment and examine the mediating role of self-leadership in this relationship among collegiate Taekwondo athletes in South Korea. A total of 147 survey data were analyzed by structural equation modeling. Results: The findings revealed that super-leadership was found to have a positive impact on both athletes' self-leadership (ß = 0.71, p < 0.001) and exercise commitment (ß = 0.30, p < 0.05). Additionally, the study reveals athletes' self-leadership significantly impacts exercise commitment (ß = 0.34, p < 0.05). Our findings also demonstrate that self-leadership was identified as a partial mediator in the relationship between super-leadership and exercise commitment (∆χ2 = 4.46, p > 0.05). Discussion: Theoretical and practical implications were discussed based on the current study's findings.

Advancing Cancer Treatment: Enhanced Combination Therapy through Functionalized Porous Nanoparticles.

Cancer remains a major global health challenge, necessitating the development of innovative treatment strategies. This review focuses on the functionalization of porous nanoparticles for combination therapy, a promising approach to enhance cancer treatment efficacy while mitigating the limitations associated with conventional methods. Combination therapy, integrating multiple treatment modalities such as chemotherapy, phototherapy, immunotherapy, and others, has emerged as an effective strategy to address the shortcomings of individual treatments. The unique properties of mesoporous silica nanoparticles (MSN) and other porous materials, like nanoparticles coated with mesoporous silica (NP@MS), metal-organic frameworks (MOF), mesoporous platinum nanoparticles (mesoPt), and carbon dots (CDs), are being explored for drug solubility, bioavailability, targeted delivery, and controlled drug release. Recent advancements in the functionalization of mesoporous nanoparticles with ligands, biomaterials, and polymers are reviewed here, highlighting their role in enhancing the efficacy of combination therapy. Various research has demonstrated the effectiveness of these nanoparticles in co-delivering drugs and photosensitizers, achieving targeted delivery, and responding to multiple stimuli for controlled drug release. This review introduces the synthesis and functionalization methods of these porous nanoparticles, along with their applications in combination therapy.

Somatodendritic organization of pacemaker activity in midbrain dopamine neurons.

The slow and regular pacemaking activity of midbrain dopamine (DA) neurons requires proper spatial organization of the excitable elements between the soma and dendritic compartments, but the somatodendritic organization is not clear. Here, we show that the dynamic interaction between the soma and multiple proximal dendritic compartments (PDCs) generates the slow pacemaking activity in DA neurons. In multipolar DA neurons, spontaneous action potentials (sAPs) consistently originate from the axon-bearing dendrite. However, when the axon initial segment was disabled, sAPs emerge randomly from various primary PDCs, indicating that multiple PDCs drive pacemaking. Ca2+ measurements and local stimulation/perturbation experiments suggest that the soma serves as a stably-oscillating inertial compartment, while multiple PDCs exhibit stochastic fluctuations and high excitability. Despite the stochastic and excitable nature of PDCs, their activities are balanced by the large centrally-connected inertial soma, resulting in the slow synchronized pacemaking rhythm. Furthermore, our electrophysiological experiments indicate that the soma and PDCs, with distinct characteristics, play different roles in glutamate- induced burst-pause firing patterns. Excitable PDCs mediate excitatory burst responses to glutamate, while the large inertial soma determines inhibitory pause responses to glutamate. Therefore, we could conclude that this somatodendritic organization serves as a common foundation for both pacemaker activity and evoked firing patterns in midbrain DA neurons.

Role of Functionalized Peptides in Nanomedicine for Effective Cancer Therapy.

Peptide-functionalized nanomedicine, which addresses the challenges of specificity and efficacy in drug delivery, is emerging as a pivotal approach for cancer therapy. Globally, cancer remains a leading cause of mortality, and conventional treatments, such as chemotherapy, often lack precision and cause adverse effects. The integration of peptides into nanomedicine offers a promising solution for enhancing the targeting and delivery of therapeutic agents. This review focuses on the three primary applications of peptides: cancer cell-targeting ligands, building blocks for self-assembling nanostructures, and elements of stimuli-responsive systems. Nanoparticles modified with peptides improved targeting of cancer cells, minimized damage to healthy tissues, and optimized drug delivery. The versatility of self-assembled peptide structures makes them an innovative vehicle for drug delivery by leveraging their biocompatibility and diverse nanoarchitectures. In particular, the mechanism of cell death induced by self-assembled structures offers a novel approach to cancer therapy. In addition, peptides in stimuli-responsive systems enable precise drug release in response to specific conditions in the tumor microenvironment. The use of peptides in nanomedicine not only augments the efficacy and safety of cancer treatments but also suggests new research directions. In this review, we introduce systems and functionalization methods using peptides or peptide-modified nanoparticles to overcome challenges in the treatment of specific cancers, including breast cancer, lung cancer, colon cancer, prostate cancer, pancreatic cancer, liver cancer, skin cancer, glioma, osteosarcoma, and cervical cancer.

Light-Responsive Layer-By-Layer Film Containing Gold Nanorods for Sequential Drug Release.

Chemically and physically stable multidrug-loaded layer-by-layer (LbL) films are promising candidates for sequential and on-demand drug release at concentrations suitable for various applications. The synergistic effect of the sequential release of drugs may enhance their therapeutic efficacy in treating skin cancer and other complex medical conditions. In this study, we prepared LbL films by alternating the deposition of cationic linear polyethylenimine, camptothecin (CPT)-loaded gold nanorods (GNRs), anionic poly(styrenesulfonate), and doxorubicin (DOX) based on electrostatic interactions. The film exhibited loading of CPT and DOX, which could be tuned according to the requirements of the application by changing the parameters of the LbL process. Herein, CPT was encapsulated in GNRs and showed good stability and absorption in the near-infrared (NIR) range (650-900 nm). The prepared LbL film showed a pH-dependent DOX release. Subsequently, the functionalized GNRs showed excellent photothermal properties, which assisted the on-demand release of CPT upon NIR irradiation with further release of DOX. Our results suggest that the LbL approach for sequential drug release can be an effective drug delivery platform owing to its cytocompatibility, anticancer effects, and stimuli-responsive properties.

P. mirabilis-derived pore-forming haemolysin, HpmA drives intestinal alpha-synuclein aggregation in a mouse model of neurodegeneration.

BACKGROUND: Recent studies suggesting the importance of the gut-microbiome in intestinal aggregated alpha synuclein (α-syn) have led to the exploration of the possible role of the gut-brain axis in central nervous system degeneration. Proteus mirabilis (P. mirabilis), a gram-negative facultative anaerobic bacterium, has been linked to brain neurodegeneration in animal studies. We hypothesised that P. mirabilis-derived virulence factors aggregate intestinal α-synuclein and could prompt the pathogenesis of dopaminergic neurodegeneration in the brain. METHODS: We used vagotomised- and antibiotic-treated male murine models to determine the pathogenesis of P. mirabilis during brain neurodegeneration. The neurodegenerative factor that is driven by P. mirabilis was determined using genetically mutated P. mirabilis. The pathological functions and interactions of the virulence factors were determined in vitro. FINDINGS: The results showed that P. mirabilis-induced motor dysfunction and neurodegeneration are regulated by intestinal α-syn aggregation in vagotomised- or antibiotic-treated murine models. We deduced that the specific virulence factor, haemolysin A (HpmA), plays a role in the pathogenesis of P. mirabilis. HpmA is involved in α-synuclein oligomerisation and membrane pore formation, resulting in the activation of mTOR-mediated autophagy signalling in intestinal neuroendocrine cells. INTERPRETATION: Taken together, the results of the present study suggest that HpmA can interact with α-syn and act as a possible indicator of brain neurodegenerative diseases that are induced by P. mirabilis. FUNDING: This study was supported by a grant from the National Research Foundation of Korea.

Peripheral metabolic alterations associated with pathological manifestations of Parkinson's disease in gut-brain axis-based mouse model.

Introduction: Parkinson's disease (PD) is a representative neurodegenerative disease, and its diagnosis relies on the evaluation of clinical manifestations or brain neuroimaging in the absence of a crucial noninvasive biomarker. Here, we used non-targeted metabolomics profiling to identify metabolic alterations in the colon and plasma samples of Proteus mirabilis (P. mirabilis)-treated mice, which is a possible animal model for investigating the microbiota-gut-brain axis. Methods: We performed gas chromatography-mass spectrometry to analyze the samples and detected metabolites that could reflect P. mirabilis-induced disease progression and pathology. Results and discussion: Pattern, correlation and pathway enrichment analyses showed significant alterations in sugar metabolism such as galactose metabolism and fructose and mannose metabolism, which are closely associated with energy metabolism and lipid metabolism. This study indicates possible metabolic factors for P. mirabilis-induced pathological progression and provides evidence of metabolic alterations associated with P. mirabilis-mediated pathology of brain neurodegeneration.

Smart Delivery Platform Using Core-Shell Nanofibers for Sequential Drug Release in Wound Healing.

An effective approach to accelerating wound healing is through a smart delivery platform that releases drugs according to the needs of different healing periods. With the growing demand for wound care and treatment, electrospun nanofibers have attracted considerable attention owing to their simple and versatile method of manufacturing, unique structure, and biological functions similar to those of the extracellular matrix. Moreover, nanofibers can be loaded with active substances that promote targeted wound healing. In this study, we investigated the performance of a core-shell nanofiber platform loaded with two drugs in the core and shell, respectively. The shell polymer, poly-l-lactic acid, initially releases the encapsulated drug into an aqueous solution at room temperature. Gold nanorods with near-infrared absorbance were incorporated in the core polymer poly(N-isopropylacrylamide) to produce localized heat by plasmon resonance when exposed to light. This allows the thermally responsive core polymer to swell and shrink for programmable drug release. Our study provides a versatile platform for controlled and safe drug delivery to wound sites and could be applied to the treatment of other topical diseases.

5-Hydroxytryptophan Reduces Levodopa-Induced Dyskinesia via Regulating AKT/mTOR/S6K and CREB/ΔFosB Signals in a Mouse Model of Parkinson's Disease.

Long-term administration of levodopa (L-DOPA) to patients with Parkinson's disease (PD) commonly results in involuntary dyskinetic movements, as is known for L-DOPA-induced dyskinesia (LID). 5-Hydroxytryptophan (5-HTP) has recently been shown to alleviate LID; however, no biochemical alterations to aberrant excitatory conditions have been revealed yet. In the present study, we aimed to confirm its anti-dyskinetic effect and to discover the unknown molecular mechanisms of action of 5-HTP in LID. We made an LID-induced mouse model through chronic L-DOPA treatment to 6-hydroxydopamine-induced hemi-parkinsonian mice and then administered 5-HTP 60 mg/kg for 15 days orally to LID-induced mice. In addition, we performed behavioral tests and analyzed the histological alterations in the lesioned part of the striatum (ST). Our results showed that 5-HTP significantly suppressed all types of dyskinetic movements (axial, limb, orolingual and locomotive) and its effects were similar to those of amantadine, the only approved drug by Food and Drug Administration. Moreover, 5-HTP did not affect the efficacy of L-DOPA on PD motor manifestations. From a molecular perspective, 5-HTP treatment significantly decreased phosphorylated CREB and ΔFosB expression, commonly known as downstream factors, increased in LID conditions. Furthermore, we found that the effects of 5-HTP were not mediated by dopamine1 receptor (D1)/DARPP32/ERK signaling, but regulated by AKT/mTOR/S6K signaling, which showed different mechanisms with amantadine in the denervated ST. Taken together, 5-HTP alleviates LID by regulating the hyperactivated striatal AKT/mTOR/S6K and CREB/ΔFosB signaling.

Janus Distillation Membrane via Mussel-Inspired Inkjet Printing Modification for Anti-Oil Fouling Membrane Distillation.

In this work, inkjet printing technology was used to print a thin layer of a hydrophilic solution containing polydopamine as a binder and polyethyleneimine as a strong hydrophilic agent on a commercial hydrophobic membrane to produce a Janus membrane for membrane distillation. The pristine and modified membranes were tested in a direct-contact membrane distillation system with mineral oil-containing feedwater. The results revealed that an integrated and homogenous hydrophilic layer was printed on the membrane with small intrusions in the pores. The membrane, which contained three layers of inkjet-printed hydrophilic layers, showed a high underwater oil contact angle and a low in-air water contact angle. One-layer inkjet printing was not robust enough, but the triple-layer coated modified membrane maintained its anti-oil fouling performance even for a feed solution containing 70 g/L NaCl and 0.01 v/v% mineral oil concentration with a flux of around 20 L/m2h. This study implies the high potential of the inkjet printing technique as a facile surface modification strategy to improve membrane performance.

Microbubble Delivery Platform for Ultrasound-Mediated Therapy in Brain Cancers.

The blood-brain barrier (BBB) is one of the most selective endothelial barriers that protect the brain and maintains homeostasis in neural microenvironments. This barrier restricts the passage of molecules into the brain, except for gaseous or extremely small hydrophobic molecules. Thus, the BBB hinders the delivery of drugs with large molecular weights for the treatment of brain cancers. Various methods have been used to deliver drugs to the brain by circumventing the BBB; however, they have limitations such as drug diversity and low delivery efficiency. To overcome this challenge, microbubbles (MBs)-based drug delivery systems have garnered a lot of interest in recent years. MBs are widely used as contrast agents and are recently being researched as a vehicle for delivering drugs, proteins, and gene complexes. The MBs are 1-10 µm in size and consist of a gas core and an organic shell, which cause physical changes, such as bubble expansion, contraction, vibration, and collapse, in response to ultrasound. The physical changes in the MBs and the resulting energy lead to biological changes in the BBB and cause the drug to penetrate it, thus enhancing the therapeutic effect. Particularly, this review describes a state-of-the-art strategy for fabricating MB-based delivery platforms and their use with ultrasound in brain cancer therapy.

Proximal dendritic localization of NALCN channels underlies tonic and burst firing in nigral dopaminergic neurons.

In multipolar nigral dopamine (DA) neurons, the highly excitable proximal dendritic compartments (PDCs) and two Na+ -permeable leak channels, TRPC3 and NALCN, play a key role in pacemaking. However, the causal link between them is unknown. Here we report that the proximal dendritic localization of NALCN underlies pacemaking and burst firing in DA neurons. Our morphological analysis of nigral DA neurons reveals that TRPC3 is ubiquitously expressed in the whole somatodendritic compartment, but NALCN is localized within the PDCs. Blocking either TRPC3 or NALCN channels abolished pacemaking. However, only blocking NALCN, not TRPC3, degraded burst discharges. Furthermore, local glutamate uncaging readily induced burst discharges within the PDCs, compared with other parts of the neuron, and NALCN channel inhibition dissipated burst generation, indicating the importance of NALCN to the high excitability of PDCs. Therefore, we conclude that PDCs serve as a common base for tonic and burst firing in nigral DA neurons. KEY POINTS: Midbrain dopamine (DA) neurons are slow pacemakers that can generate tonic and burst firings, and the highly excitable proximal dendritic compartments (PDCs) and two Na+ -permeable leak channels, TRPC3 and NALCN, play a key role in pacemaking. We find that slow tonic firing depends on the basal activity of both the NALCN and TRPC3 channels, but that burst firing does not require TRPC3 channels but relies only on NALCN channels. We find that TRPC3 is ubiquitously expressed in the entire somatodendritic compartment, but that NALCN exists only within the PDCs in nigral DA neurons. We show that NALCN channel localization confers high excitability on PDCs and is essential for burst generation in nigral DA neurons. These results suggest that PDCs serve as a common base for tonic and burst firing in nigral DA neurons.

Effects of Nanobubbles in Dermal Delivery of Drugs and Cosmetics.

Dermal delivery, which delivers drugs and cosmetics through the skin, has attracted significant attention due to its non-invasive and simple administration compared with oral or injectable administration. However, delivery of the ingredients through the skin barrier is difficult because the primary function of the skin is to protect the human body by preventing the invasion of contaminants. Although various techniques have been developed to overcome skin barriers, chemical toxicity, complicated processes, and expensive equipment still remain as obstacles. Moreover, green chemistry, which minimizes or eliminates the use of toxic chemicals, is required in the cosmetic industry. Thus, the development of a new method for dermal delivery is required. In this study, we provide a new method for dermal delivery using nanobubbles (NBs). NBs generated in oil improve the delivery effect of the active ingredients through the high Brownian motion and charge-balancing effect. Franz cell experiments and depigmentation experiments using the B16F10 melanoma cells were conducted to confirm the enhanced delivery effects. The system using NBs will contribute to the advancement of the dermal delivery of drugs and cosmetics.

Association of Driving Fitness and Driving Efficacy in the Elderly with Generalized Anxiety Disorder.

Purpose: The purpose of this study was to investigate the relationship between driving fitness and driving efficacy in elderly patients with generalized anxiety disorder and identify factors influencing anxiety. Methods: The anxiety level, driving efficacy, and driving performance were assessed for 45 elderly drivers who had been diagnosed with or were suspected of having an anxiety disorder in the past. The Korean-Self-rating Anxiety Scale (K-SAS), Korean-Adelaide Driving Self-Efficacy Scale (K-ADSES), and Korean-Drivers 65 Plus (K-D65+) were used as test tools. Factors affecting anxiety and the differences between the groups with high anxiety symptoms and anxiety in the normal range were analyzed. Results: There were differences in driving efficiency and driving performance between elderly drivers with anxiety scores in the normal range and those with mild-to-moderate anxiety (p < 0.05). Significant factors (p < 0.001) influencing driving anxiety in the high anxiety group were GAD duration (ß = 0.170), driving difficulty (ß = 10.648), drug use (ß = 0.656), traffic sign/signal awareness (ß = -0.870). Conclusion: Our results suggest that a combination of a driving rehabilitation approach and interventions that can provide emotional support and reduce mental health anxiety, as well as exposure treatment for driving performance training, may be necessary for driving rehabilitation of the elderly with generalized anxiety disorder.

Identification of a potent NAFLD drug candidate for controlling T2DM-mediated inflammation and secondary damage in vitro and in vivo.

Accumulation of glucose/sugar results in the formation of reactive di-carbonyl compounds such as MGO and GO that interact with several amino acids and proteins to form toxic advanced glycation end products (AGEs). Induction of AGEs breakdown can control symptoms and severity in T2DM and other related complications like NAFLD where AGEs are the key players. Therefore, an AGE cross-link breaker has been suggested for preventing the onset/progression of NAFLD. In this study, we reported novel synthetic naphthalene-2-acyl thiazolium derivatives (KHAGs). Among synthesized KHAG derivatives, we observed that a novel KHAG-04, a 1,4-dimethoxynaphthalen-2-acyl thiazolium salt which is an analog of alagebrium, dramatically cleaves MGO/GO-AGE cross-links, and it also inhibited inflammation by lowering the level of nitric oxide production and IL-1ß and TNF-α secretion in LPS and/or MGO-AGE-activated macrophage. Moreover, it also reduced FFA and MGO-AGE-induced lipogenesis in Hep-G2 cells. In mice, KHAG-04 significantly reduced the level of glyoxal in the liver, which was induced by DMC. Furthermore, KHAG-04 treatment significantly reduced blood glucose levels, lipid accumulation, and inflammation in the NAFLD/T2DM animal model. Novel KHAG-04-mediated induction of AGEs breakdown could be the possible reason for its anti-inflammatory, antihyperglycemic, and anti-lipidemic effects in cells and NAFLD in the T2DM animal model, respectively. Further research might explore the pharmacological efficacy and usefulness and consider the ability of this compound in the treatment strategy against various models of NAFLD in T2DM where MGO/GO-AGEs play a key role in the pathogenesis.

Lactococcus lactis KF140 Reduces Dietary Absorption of Nε - (Carboxymethyl)lysine in Rats and Humans via ß-Galactosidase Activity.

Background and Aims: Excessive intake of advanced glycation end products (AGEs), which are formed in foods cooked at high temperatures for long periods of time, has negative health effects, such as inflammatory responses and oxidative stress. Nε-(Carboxymethyl)lysine (CML) is one of the major dietary AGEs. Given their generally recognized as safe status and probiotic functionalities, lactic acid bacteria may be ideal supplements for blocking intestinal absorption of food toxicants. However, the protective effects of lactic acid bacteria against dietary AGEs have not been fully elucidated. Materials and Methods: We investigated the effect of treatment with Lactococcus lactis KF140 (LL-KF140), which was isolated from kimchi, on the levels and toxicokinetics of CML. The CML reduction efficacies of the Lactococcus lactis KF140 (LL-KF140), which was isolated from kimchi, were conducted by in vitro test for reducing CML concentration of the casein-lactose reaction product (CLRP) and in vivo test for reducing serum CML level of LL-KF140 administered rats at 2.0 × 108 CFU/kg for14 days. In addition, 12 volunteers consuming LL-KF140 at 2.0 × 109 CFU/1.5 g for 26 days were determined blood CML concentration and compared with that before intake a Parmesan cheese. Results: Administration of LL-KF140 reduced serum CML levels and hepatic CML absorption in rats that were fed a CML-enriched product. In a human trial, the intake of LL-KF140 prevented increases in the serum levels of CML and alanine aminotransferase after consumption of a CML-rich cheese. LL-KF140 was determined to presence in feces through metagenome analysis. Furthermore, ß-galactosidase, one of the L. lactis-produced enzymes, inhibited the absorption of CML and reduced the levels of this AGE, which suggests an indirect inhibitory effect of LL-KF140. This study is the first to demonstrate that an L. lactis strain and its related enzyme contribute to the reduction of dietary absorption of CML.

Dimensionally controlled graphene-based surfaces for photothermal membrane crystallization.

Membrane-based photothermal crystallization - a pioneering technology for mining valuable minerals from seawater and brines - exploits self-heating nanostructured interfaces to boost water evaporation, so achieving a controlled supersaturation environment that promotes the nucleation and growth of salts. This work explores, for the first time, the use of two-dimensional graphene thin films (2D-G) and three dimensional vertically orientated graphene sheet arrays (3D-G) as potential photothermal membranes applied to the dehydration of sodium chloride, potassium chloride and magnesium sulfate hypersaline solutions, followed by salt crystallization. A systematic study sheds light on the role of vertical alignment of graphene sheets on the interfacial, light absorption and photothermal characteristics of the membrane, impacting on the water evaporation rate and on the crystal size distribution of the investigated salts. Overall, 3D-G facilitates the crystallization of the salts because of superior light-to-heat conversion leading to a 3-fold improvement of the evaporation rate with respect to 2D-G. The exploitation of sunlight graphene-based interfaces is demonstrated as a potential sustainable solution to aqueous wastes valorization via recovery in solid phase of dissolved salts using renewable solar energy.

Role Value, Occupational Balance, and Quality of Life: A Cross-Sectional Study on Exploring the Urban Older People Perspective in South Korea.

The purpose of this study was to investigate the role value, occupational balance, and quality of life among urban older adults in South Korea. We recruited 90 urban older adults in Seoul, Gyeonggi-do and Chungcheong-do. Assessments used (1) Role Checklist, (2) Life Balance Inventory (LBI), and (3) WHO Quality of Life Scale abbreviated version (WHOQOL-BREF). Our results showed that the roles that were perceived as very valuable were as family members, housekeepers, and guardians (in descending order). The roles that were perceived as less valuable were students, volunteers, and organizational members (in descending order). The activities that individuals were actively pursuing were hygiene management, rest, and healthy eating (in descending order). By contrast, the activities that were not being actively pursued were composing (music, poetry), preparing for event planning, dancing, yoga, and taekwondo. The total score of the Role Checklist and WHOQOL-BREF total (r = 0.343, p < 0.01), K-LBI total and WHOQOL-BREF total (r = 0.386, p < 0.01), and role value total and K-LBI (r = 323, p < 0.01) showed a statistically significant correlation. As a result of the regression analysis, the sub-item of work balance that affected the quality of life was managing appearance (R2 = 51.7, p < 0.001). These data showed that the role of urban older adults in Korea was mainly played within the family. The level of participation was low in the areas of instrumental daily life activities, work, leisure, and social participation. We propose that this population needs to be provided with opportunities for active aging through broader professional participation.

Stimuli-Responsive Adaptive Nanotoxin to Directly Penetrate the Cellular Membrane by Molecular Folding and Unfolding.

Biological nanomachines, including proteins and nucleic acids whose function is activated by conformational changes, are involved in every biological process, in which their dynamic and responsive behaviors are controlled by supramolecular recognition. The development of artificial nanomachines that mimic the biological functions for potential application as therapeutics is emerging; however, it is still limited to the lower hierarchical level of the molecular components. In this work, we report a synthetic machinery nanostructure in which actuatable molecular components are integrated into a hierarchical nanomaterial in response to external stimuli to regulate biological functions. Two nanometers core-sized gold nanoparticles are covered with ligand layers as actuatable components, whose folding/unfolding motional response to the cellular environment enables the direct penetration of the nanoparticles across the cellular membrane to disrupt intracellular organelles. Furthermore, the pH-responsive conformational movements of the molecular components can induce the apoptosis of cancer cells. This strategy based on the mechanical motion of molecular components on a hierarchical nanocluster would be useful to design biomimetic nanotoxins.

Highly stable gold nanolayer membrane for efficient solar water evaporation under a harsh environment.

Interfacial solar water evaporation has attracted tremendous attention for sunlight harvesting for water purification. However, salt formation and stability of the photothermal materials (PTMs) remain a challenge that need addressing before bringing this technology to real-world applications. In this work, a nanoscale thin film of gold (Au) on a polytetrafluoroethylene (PTFE) membrane has been prepared using a magnetic sputtering technique. The fabricated membrane displays a robust mechanical strength and chemical stability arising from the adhesiveness of the thin film Au nanolayer on the PTFE membrane as well as the chemical inertness of the noble metal PTM. The Au nanolayer/PTFE membrane with cellulose sponge substrate resulted in an evaporation rate of 0.88 kg m-2 h-1 under 1 sun intensity. Remarkable salt ion rejection of 99.9% has been obtained, meeting the required standard for drinking water. Moreover, the membrane exhibited excellent stability and reusability in natural seawater and high salinity brine (150 g/L) and even in severe conditions (acidic, basic, and oxidized). No noticeable salt formation was observed on the evaporator surface after the tests. These findings reveal promising prospects for using a magnetron sputtering technique to fabricate a stable photothermal membrane for seawater and high salinity brine desalination.