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Carbonaceous and alternative supporting materials for platinum (Pt) and palladium (Pd) have been explored for the cathodic electrocatalysis in low-temperature fuel cells. Pd and Pt are widely used for catalysis owing to their remarkable electrocatalytic activity toward water splitting and fuel cell reactions. Supporting materials play a paramount role in defining electrocatalytic properties such as durability, selectivity, and activity. The conventional supporting material such as carbon black is unable to fit all the requirements under the severe operating conditions of fuel cells due to its poor corrosion resistance and limited mass transport of fuels to active catalyst sites. Nowadays the scientific research is being concentrated on devising different altered carbonic and carbon-free supporting materials for catalysts to improve the catalytic activity, stability, and selectivity of noble metal electrocatalysts. Lately, Pt, Pd and their alloy catalysts supported on modified carbonaceous and carbon-free materials have attracted solid interest owing to their prominent characteristics contributing to the remarkable fuel cell efficacy. Therefore, it is reasonable to explore this theme, regarding a variety of supporting materials, their advantages, drawbacks and future perspectives. In this mini-review, we selectively summarize recent advancements on several types of key supporting materials: carbon (graphene, carbon nanotubes, mesoporous carbon, and doped carbon nanostructures), non-carbon (transition metals oxides, borides, nitrides, and carbides) and hybrid nanocomposites.

As higher education faces challenges in driving innovation, the effectiveness of academic leaders affects an institution’s overall performance. In Taiwan, most of the leading research focuses on leadership in primary and secondary schools. In this study, we interviewed a public university’s academic and administrative directors to outline the responsibilities and expectations of academic leaders, and investigated the problems and challenges that they faced during their work process to propose the support and leadership development needed for them to navigate through the obstacles and challenges. The results illustrate that an ideal academic leader should possess the following essential qualities and skills: enthusiasm, empathy, fairness and openness, and interpersonal communication skills. Academic leaders are faced with problems including budget, student enrollment, professors’ rights, and conflicts between professors and students, and challenges resulting from social change, such as faculty recruitment, student career development, university transformation and self-efficacy in administration. According to these findings, we propose suggestions for revising election procedures of institutional leaders and a leadership development program. The study contributes to this research field by offering insights of the problems and challenges of transiting from a faculty member to an administrator and by proposing a support system to enhance department leaders’ awareness of the importance of their roles and responsibilities in building consensus toward university development direction.

The urgent need of catalysts with improved performances toward the hydrogen evolution reaction (HER) is still one of the crucial issues for the water splitting electrocatalysis. Herein, we exhibit ...

Background:Identifying neural substrates that are differentially affected by drugs of abuse and natural rewards is key to finding a target for an efficacious treatment for substance abuse. Melanin-concentrating hormone is a polypeptide with an inhibitory effect on the mesolimbic dopamine system. Here we test the hypothesis that melanin-concentrating hormone in the lateral hypothalamus and nucleus accumbens shell is differentially involved in the regulation of morphine and food-rewarded behaviors.Methods:Male Sprague–Dawley rats were trained with morphine (5.0 mg/kg, subcutaneously) or food pellets (standard chow, 10–14 g) to induce a conditioned place preference, immediately followed by extinction training. Melanin-concentrating hormone (1.0 µg/side) or saline was infused into the nucleus accumbens shell or lateral hypothalamus before the reinstatement primed by morphine or food, and locomotor activity was simultaneously monitored. As the comparison, melanin-concentrating hormone was also microinjected into the nucleus accumbens shell or lateral hypothalamus before the expression of food or morphine-induced conditioned place preference.Results:Microinfusion of melanin-concentrating hormone into the nucleus accumbens shell (but not into the lateral hypothalamus) prevented the reinstatement of morphine conditioned place preference but had no effect on the reinstatement of food conditioned place preference. In contrast, microinfusion of melanin-concentrating hormone into the lateral hypothalamus (but not in the nucleus accumbens shell) inhibited the reinstatement of food conditioned place preference but had no effect on the reinstatement of morphine conditioned place preference.Conclusions:These results suggest a clear double dissociation of melanin-concentrating hormone in morphine/food rewarding behaviors and melanin-concentrating hormone in the nucleus accumbens shell. Melanin-concentrating hormone could be a potential target for therapeutic intervention for morphine abuse without affecting natural rewards.

This paper introduces an approach to synthesize bimetallic nanoparticles under an alternating temperature field in aqueous solution. During the synthesis, pyro-catalytic barium titanate is used as the substrate to reduce the metallic ions dispersed in the solution due to the generated charges at the surface of pyro-materials under temperature oscillation. Chloroauric acid and potassium tetrachloroplatinate are used as precursors to produce gold/platinum bimetallic nanoparticles through a pyro-catalytic process. Transmission electron microscopy characterization, in combination with energy dispersive X-ray spectroscopy mapping, demonstrates that the bimetallic nanoparticle is composed of an Au core and Au/Pt alloy shell structure. Compared to the conventional approaches, the pyroelectric synthesis approach demonstrated in this work requires no toxic reducing agents and waste heat can be used as a thermal energy source in the synthesis. Hence, it offers a potential “green” synthetic method for bimetallic nanoparticles.

The interaction between water and graphene oxide (GO), including water adsorption and desorption, has been widely used to demonstrate moisture-electric energy transformation (MEET). By taking advantage of water desorption stimulated by infrared (IR) light from a graphene oxide film with a gradient of oxygen-containing groups (O-group), a self-powered IR detection approach that can convert IR light into electric signals is demonstrated. The temperature sensitivity reaches 4.2 mK. With further optimization of the materials and structures, the performance of such self-powered IR detection can be further improved. The mechanism of the detection involving an IR/thermal effect on the interaction between vapor molecules and solid materials also has potential applications in thermal detection, thermal energy conversion, and chemical sensing.

Converting solar energy into storable thermal energy within organic phase change materials has emerged as a promising way to overcome solar intermittency and continuously harness solar-thermal energy for many heating-related applications. The low thermal conductivity and leakage issue of the phase change materials, however, limit scalable solar-thermal energy storage and their practical applications. Inspired by the dynamic thermoregulation behavior of butterfly wings, here we demonstrate rapid roll-to-roll solar-thermal energy harvesting within flexible form-stable composite phase change materials. Instead of static charging the bulk materials, the thin composite sheets are exposed to solar radiation for rapid charging while being continuously rolled. Due to shortened heat-diffusion distance and rollability of the composites, it achieves fast uniform solar-thermal energy storage within the bulk storage media. The flexibility of charged composites also enables broad tuning of the discharging behavior, and offers the possibility to explore wearable thermotherapy and other flexible solar-thermal applications.

Reservoirs are artificial ecosystems that modify the hydrological and environmental components nearby. The long-term monitoring of fish assemblages in reservoirs may provide key information to understand how these artificial ecosystems allow fish population fluctuations and identify proper conservation strategies. A sentinel-site approach method assessed changes in fish assemblages in the Feitsui Reservoir (1024 ha) over 14 years, including the periods 2006–2008, 2010–2011, 2016, 2018, and 2020. Fish assemblages, sampled using gill nets, were composed of 38 species (12 families and 8 orders) with Cyprinidae as the dominant family; the fish fauna were dominated by species of the family Cyprinidae (71%) and Cichlidae (20.3%). Principal component analysis and nonmetric multidimensional scaling categorized the assemblages into two groups (cold and warm seasons), and we identified three parameters that were significantly correlated with the season (p < 0.05): SD (R = −0.04), Chl-a (R = 0.01), and algal count (R = 0.19); the algal count was higher in the warm season than in the cold season. The fish assemblage in the cold and warm seasons contained no exclusive taxa, contributing to the dissimilarity between the groups. The fish assemblage for the years before and after 2010 indicated partial overlap between the two groups; S. macrops contributed greatly to the separation of the two periods (>10% each; SIMPER) and O. mossambicus was dominant in assemblage structures after 2010. Our findings show the importance of long-term fish monitoring for the investigation of the effects of nonnative fish species on native fish species composition.

Purpose The use of nanocarriers to improve the delivery and efficacy of antimetastatic agents is less explored when compared to cytotoxic agents. This study reports the entrapment of an antimetastatic Signal Transducer and Activator of Transcription 3 (STAT3) dimerization blocker, Stattic (S) into a chitosan-coated-poly(lactic-co-glycolic acid) (C-PLGA) nanocarrier and the improvement on the drug’s physicochemical, in vitro and in vivo antimetastatic properties post entrapment. Methods In vitro, physicochemical properties of the Stattic-entrapped C-PLGA nanoparticles (S@C-PLGA) and Stattic-entrapped PLGA nanoparticles (S@PLGA, control) in terms of size, zeta potential, polydispersity index, drug loading, entrapment efficiency, Stattic release in different medium and cytotoxicity were firstly evaluated. The in vitro antimigration properties of the nanoparticles on breast cancer cell lines were then studied by Scratch assay and Transwell assay. Study on the in vivo antitumor efficacy and antimetastatic properties of S@C-PLGA compared to Stattic were then performed on 4T1 tumor bearing mice. Results The S@C-PLGA nanoparticles (141.8 ± 2.3 nm) was hemocompatible and exhibited low Stattic release (12%) in plasma. S@C-PLGA also exhibited enhanced in vitro anti-cell migration potency (by >10-fold in MDA-MB-231 and 5-fold in 4T1 cells) and in vivo tumor growth suppression (by 33.6%) in 4T1 murine metastatic mammary tumor bearing mice when compared to that of the Stattic-treated group. Interestingly, the number of lung and liver metastatic foci was found to reduce by 50% and 56.6%, respectively, and the average size of the lung metastatic foci was reduced by 75.4% in 4T1 tumor-bearing mice treated with S@C-PLGA compared to Stattic-treated group (p < 0.001). Conclusion These findings suggest the usage of C-PLGA nanocarrier to improve the delivery and efficacy of antimetastatic agents, such as Stattic, in cancer therapy., Graphical Abstract

Dynamic localization, which originates from the phenomena of particle evolution suppression under an externally applied AC electric field, has been simulated by suppressed light evolution in periodically-curved photonic arrays. However, experimental studies on their quantitative dynamic transport properties and application for quantum information processing are rare. Here we fabricate one-dimensional and hexagonal two-dimensional arrays, both with sinusoidal curvature. We successfully observe the suppressed single-photon evolution patterns, and for the first time measure the variances to study their transport properties. For one-dimensional arrays, the measured variances match both the analytical electric field calculation and the quantum walk Hamiltonian engineering approach. For hexagonal arrays, as anisotropic effective couplings in four directions are mutually dependent, the analytical approach suffers, while quantum walk conveniently incorporates all anisotropic coupling coefficients in the Hamiltonian and solves its exponential as a whole, yielding consistent variances with our experimental results. Furthermore, we implement a nearly complete localization to show that it can preserve both the initial injection and the wave-packet after some evolution, acting as a memory of a flexible time scale in integrated photonics. We demonstrate a useful quantum simulation of dynamic localization for studying their anisotropic transport properties, and a promising application of dynamic localization as a building block for quantum information processing in integrated photonics., Comment: 4 figures

We demonstrate a rapid one-step scalable microwave heating-based method to prepare Ti

Retracted on authors' request due to detected data flaws. Reference: Rui Zhang, Jibin Li, Xiaofei Yan, Keer Jin, Wenya Li, Xin Liu, Jianfeng Zhao, Wen Shang, Yefu Liu. Long Noncoding RNA Plasmacytoma Variant Translocation 1 (PVT1) Promotes Colon Cancer Progression via Endogenous Sponging miR-26b. Med Sci Monit. 2018; 24: LBR8685-8692. 10.12659/MSM.910955.

The P1/HC-Pro viral suppressor of potyvirus suppresses posttranscriptional gene silencing (PTGS). The fusion protein of P1/HC-Pro can be cleaved into P1 and HC-Pro through the P1 self-cleavage activity, and P1 is necessary and sufficient to enhance PTGS suppression of HC-Pro. To address the modulation of gene regulatory relationships induced by turnip mosaic virus (TuMV) P1/HC-Pro (P1/HC-ProTu), a comparative transcriptome analysis of three types of transgenic plants (P1Tu, HC-ProTu, and P1/HC-ProTu) were conducted using both high-throughput (HTP) and low-throughput (LTP) RNA-Seq strategies. The results showed that P1/HC-ProTu disturbed the endogenous abscisic acid (ABA) accumulation and genes in the signaling pathway. Additionally, the integrated responses of stress-related genes, in particular to drought stress, cold stress, senescence, and stomatal dynamics, altered the expressions by the ABA/calcium signaling. Crosstalk among the ABA, jasmonic acid, and salicylic acid pathways might simultaneously modulate the stress responses triggered by P1/HC-ProTu. Furthermore, the LTP network analysis revealed crucial genes in common with those identified by the HTP network in this study, demonstrating the effectiveness of the miniaturization of the HTP profile. Overall, our findings indicate that P1/HC-ProTu-mediated suppression in RNA silencing altered the ABA/calcium signaling and a wide range of stress responses.

Background: Malignant ventricular arrhythmias caused by thyroid storm, such as ventricular tachycardia (VT) or ventricular fibrillation (VF), which are life-threatening, are rare. We report the case of a patient who suffered from cardiac arrest caused by thyroid storm and the rare VF; the patient showed a favorable neurologic outcome after receiving targeted temperature management (TTM) treatment by intravascular cooling measures.Case presentation: A 24-year-old woman who had lost 20 kg in the preceding 2 months presented to the emergency department with diarrhea, vomiting, fever, and tachycardia. Thyroid function testing showed increased free triiodothyronine (FT3) and free thyroxine (FT4), decreased thyroid-stimulating hormone (TSH), and positive TSH-receptor antibody (TRAB). She was diagnosed with hyperthyroidism and had experienced sudden cardiac arrest (SCA) due to ventricular fibrillation (VF) caused by thyroid storm. The patient was performed with targeted temperature management (TTM) by intravascular cooling measures. Regular follow-up in the endocrinology department showed a good outcome.Conclusions: Our case not only suggests a new method of cooling treatment for thyroid storm, but also provides evidence for the success of TTM on patients resuscitated from in-hospital cardiac arrest (IHCA) who remain comatose after return of spontaneous circulation (ROSC).

Bundling of single-walled carbon nanotubes (SWCNTs) significantly undermines their superior thermal and electrical properties. Realizing stable, homogeneous, and surfactant-free dispersion of SWCNTs in solvents and composites has long been regarded as a key challenge. Here, we report amine-containing aromatic and cyclohexane molecules, which are common chain extenders (CEs) for epoxy curing in industry, can be used to effectively disperse CNTs. We achieve single-tube-level dispersion of SWCNTs in CE solvents, as demonstrated by the strong chirality-dependent absorption and photoluminescence emission. The SWCNT-CE dispersion remains stable under ambient conditions for months. The excellent dispersibility and stability are attributed to the formation of an n-type charge-transfer complex through the NH-π interaction between the amine group of CEs and the delocalized π bond of SWCNTs, which is confirmed by the negative Seebeck coefficient of the CE-functionalized SWCNT films, the red shift of the G band in the Raman spectra, and the NH-π peak in X-ray photoelectron spectroscopy. The high dispersibility of CEs significantly improves the electrical and thermal transport of macroscale CNT assemblies. The sheet resistance of the CE-dispersed SWCNT thin films reaches 161 Ω sq-1 at 80.8% optical transmittance after functional modification by HNO3. Moreover, the CEs cross-link CNTs and epoxy molecules, forming a pathway for phonon transport in CNT/epoxy nanocomposites. The thermal conductivity of the CE-CNT-epoxy composite is enhanced by 1850% compared with the original epoxy, which is the highest enhancement reported to date for CNT/epoxy nanocomposites. The CE-based NH-π interaction provides a new paradigm for the effective and stable dispersion of SWCNTs in a facile and scalable process.

Biological systems outperform engineered systems in many aspects due to billions of years of evolution in advance. With the integration of biological components, engineered functional systems can enjoy the benefits of biological systems, as well as the blurring of the boundary with living systems, including humans.

Electrically driven steam generation is a critical process for many heating-related applications such as sterilization and food processing. Current systems, which rely on heating up the bulk water to generate steam, face the dilemma in achieving a large evaporation flux and fast thermal response. Herein, we report a self-floating electrically driven interfacial evaporator for fast high-efficiency steam generation independent of the amount of loaded bulk water in the system. Through localized heating of the wicked water at the air–water interface, the evaporator has achieved an electrical-to-steam energy conversion efficiency of ∼90% at a heating power density of 10 kW/m2 and a fast thermal response of 20 s. The interfacial evaporation design not only achieves a high evaporation efficiency within a broad range of heating power densities by using different wicking materials, but also enables attaining a high evaporation temperature under low heating power densities by tuning the ratio of the vapor outlet area and the evaporation surface area. By integrating an interfacial evaporator within a sanitizer, the resultant system has demonstrated a faster steam temperature rise and superior steam sterilization performance than the commercial bulk heating-based approach.

Direct absorption-based solar collectors, which rely on volumetric absorption of sunlight by optical nanofluids, have emerged as a superior way to conventional surface absorption-based collectors for harvesting solar-thermal energy. In this short review, we summarize the recent progress on preparing medium-to-high-temperature solar-thermal nanofluids that can be potentially used in direct absorption-based solar collectors under concentrated solar fluxes. Emphasis is placed on discussing the challenge and strategies to achieve stable dispersion of the optical nanofluids.

Retinoblastoma(RB)is the most common intraocular malignant tumor in children, which often occurs in infants and young children. It can damage the eyesight, eyeball and even life-threatening of children. The occurrence and development is closely related to the genome and epigenome. The treatment and prognosis of hereditary RB in all cases depends on the initial stage of the disease, and when the disease is diagnosed and treated early, the survival rate exceeds 95%. The survival rate of RB was less than 50% when extraocular dissemination occurred in late stage. Therefore, the treatment focus on RB is to save the lives of children through early tumor monitoring and prevention. The secondary goal is to preserve globe salvage and to preserve vision to the maximum extent possible. The research on RB genetics is helpful to find specific targets through gene screening, monitoring and search, which is very necessary to improve the survival rate of children and to research targeted therapy.

In this work, the use of gold nanoparticles (AuNPs), synthesised using Curcuma mangga (CM) extract in photothermal killing of breast cancer (MCF-7) cells is demonstrated. CM-AuNPs showed higher photothermal heating efficiency compared to citrate-AuNPs upon irradiation with a 532 nm laser. In addition, treatment of MCF-7 cells with CM-AuNPs coupled with laser irradiation for 120 s was found to significantly reduce (72%) the cell viability compared to about 13%, obtained with citrate-AuNPs. Results from flow cytometry showed that the CM-AuNP-dependent photothermal-induced MCF-7 cells death was triggered mainly by apoptosis mechanism. All these results suggested the potential use of CM-AuNPs as therapeutic agents in cancer therapy.

This work explores an alternative vapor sensing mechanism through analyzing dynamic desorption process from butterfly wings for the differentiation of both individual and mixed vapors quantitatively. Morpho butterfly wings have been used in differentiating individual vapors, but it is challenging to use them for the differentiation of mixed vapor quantitatively. This paper demonstrates the use of Morpho butterfly wings for the sensitive and selective detection of closely related vapors in mixtures. Principal components analysis (PCA) is used to process the reflectance spectra of the wing scales during dynamic desorption of different vapors. With the desorption-based detection mechanism, individual vapors with different concentrations and mixed vapors with different mixing ratios can be differentiated using the butterfly wing based sensors. Both the original butterfly wings and butterfly wings with surface modification show the capability in distinguishing vapors in mixtures, which may offer a guideline for further improving selectivity and sensitivity of bioinspired sensors.

This paper demonstrates a facile solar steam generator for the generation of high-temperature steam at ambient pressure. The steam generator consists of a coiled copper tube (CCT) that serves as both solar collector and vapor heater. Both the inner and outer surfaces of the CCT are coated with black superhydrophobic copper oxide layer to improve the solar absorption, and such superhydrophobic layer prevents the condensation and clogging of water vapor during the heating process. Solar vapor is generated at the inlet of CCT through interfacial evaporation and subsequently heated inside the CCT as the vapor travels from the inlet to the outlet. By employing this approach, steam temperature that exceeds 100 °C under 1-sun illumination is demonstrated. Furthermore, steam temperature could reach as high as 250 °C under 10-sun illumination at ambient pressure. Successful sterilization experiment was also performed in this work to demonstrate the potential application of the high temperature steam generated. Such demonstrated approach helps open up the potential usage of solar-driven interfacial evaporation in applications that involve high-temperature steam, including medical sterilization, chemical manufacturing and food processing. Keywords: High-temperature steam, Photothermal conversion materials, Solar steam generation, Sterilization, Vapor heating

Solar-driven interfacial evaporation, as one of the most effective ways to convert and utilize solar energy, has attracted lot of interest recently. Most of the previous research studies, however, mainly focused on nonpatterned solar absorbers by improving the structural and chemical characteristics of the solar absorbers used in the interfacial evaporation systems. In this work, we investigated the influence of patterned surface on the evaporation performance of solar absorbers. The patterned surfaces studied, which include black patterns and white patterns, were achieved by selectively printing carbon black on the air-laid paper. Such a design leads to the lateral temperature differences between adjacent patterns of the solar absorber under solar illumination. The temperature differences result in the lateral heat and mass transfer between those patterns, which can effectively accelerate solar-driven vapor generation. With similar patterns and same coverage of carbon black, the increase in the circumference of the surface patterns leads to the increase in the evaporation performance. Additionally, we found that the evaporation performance can be optimized through the design of surface patterns, which demonstrates the potential in reducing the usage of the light-absorbing materials in the solar absorber. The findings in this work not only expand the understanding of the interfacial evaporation systems but also offer additional guidelines in designing interfacial evaporation systems.

Solar-thermal energy storage within phase change materials (PCMs) can overcome solar radiation intermittency to enable continuous operation of many important heating-related processes. The energy harvesting performance of current storage systems, however, is limited by the low thermal conductivity of PCMs, and the thermal conductivity enhancement of high-temperature molten salt-based PCMs is challenging and often leads to reduced energy storage capacity. Here, we demonstrate that magnetically moving mesh-structured solar absorbers within a molten salt along the solar illumination path significantly accelerates solar-thermal energy storage rates while maintaining 100% storage capacity. Such a magnetically-accelerated movable charging strategy increases the latent heat solar-thermal energy harvesting rate by 107%, and also supports large-area charging and batch-to-batch solar-thermal storage. The movable charging system can be readily integrated with heat exchanging systems to serve as energy sources for water and space heating by using abundant clean solar-thermal energy.

Direct absorption solar collectors, which use optical nanofluids to volumetrically absorb and convert sunlight into heat, have emerged as promising devices to harvest solar-thermal energy for many heat-related applications. Nanofluids, however, generally suffer from aggregation issues and the widely investigated water-based fluids only enable solar-thermal harvesting at relatively low temperatures. Herein, we report a facile way to prepare stably dispersed reduced graphene oxide-ethylene glycol (rGO-EG) fluids for solar-thermal energy harvesting at medium temperatures. Without the use of complex surface modification process, the homogeneous dispersion of rGO-EG fluids was achieved by utilizing the favorable interaction between the oxygen-containing groups on the rGO surfaces and EG molecules. The rGO-EG fluids were prepared by reducing the GO-EG fluids that are uniformly dispersed with ethanol-wetted GO through a single step of heating. The prepared rGO-EG fluids have suitable thermophysical properties for direct solar-thermal energy harvesting, such as broadband absorption of sunlight, high specific heat capacity and low viscosity. The rGO-EG fluids have shown stable uniform dispersion up to 120 °C and have demonstrated consistent solar-thermal energy harvesting performance during repeated solar radiation at ∼110 °C.

This work explores an alternative approach to generate electric energy from a solar-driven interfacial water evaporation system. A thermo-electrochemical redox couple was combined with an evaporation system to take advantage of the temperature difference between the air–liquid interface and the bulk solution of water. An open thermo-electrochemical cell (TEC) was demonstrated to achieve the parallel processes of clean water generation and also electricity generation. Both deionized (DI) water and seawater (from the East China Sea) were used for the preparation of the electrolyte of the TEC system. Under one-sun illumination, the peak output electric power of the TEC with the seawater-based electrolyte was ∼0.5 mW m−2. The electric output of the TEC with the solution of seawater still reached ∼2.3 × 10−2 mW m−2 even without solar illumination due to the temperature difference generated by natural evaporation, which provides a possibility for electricity generation at night. The TECs can also be connected in series to increase the output voltage to charge capacitors or power LEDs, as demonstrated in the work.