N-Carbon-Doped Binary Nanophase of Metal Oxide/Metal-Organic Framework for Extremely Sensitive and Selective Gas Response

Metal-organic frameworks (MOFs), which are highly ordered structures exhibiting sub-nanometer porosity, possess significant potential for diverse gas applications. However, their inherent insulative properties limit their utility in electrochemical gas sensing. This investigation successfully modifies the electrical conductivity of zeolitic imidazolte framework-8 (ZIF-8) employing a straightforward surface oxidation methodology. A ZIF-8 polycrystalline layer is applied on a wafer-scale oxide substrate and subjects to thermal annealing at 300 °C under ambient air conditions, resulting in nanoscale oxide layers while preserving the fundamental properties of the ZIF-8. Subsequent exposure to NO2 instigates the evolution of an electrically interconnected structure with the formation of electron-rich dopants derived from the decomposition of nitrogen-rich organic linkers. The N-carbon-hybridized ZnO/ZIF-8 device demonstrates remarkable sensitivity (≈130 ppm-1 ) and extreme selectivity in NO2 gas detection with a lower detection limit of 0.63 ppb under 150 °C operating temperature, surpassing the performance of existing sensing materials. The exceptional performances result from the Debye length scale dimensionality of ZnO and the high affinity of ZIF-8 to NO2 . The methodology for manipulating MOF conductivity through surface oxidation holds the potential to accelerate the development of MOF-hybridized conductive channels for a variety of electrical applications.

Metal-Organic Framework Membrane Hybridized with Graphitic Materials for Gas Separation

Metal-organic frameworks (MOFs) are an exceptional class of crystalline materials that have been extensively used to fabricate membranes for various applications such as gas separation, ion transport, and desalination due to their well-defined pore structure, chemical features, and simple synthesis process. The incorporation of graphitic carbon materials in MOFs has garnered significant attention as it can provide abundant nucleation sites and modulate gas transport by influencing the orientation or rigidity of MOF crystals without changing their porous structure. This review insights of previous studies utilizing graphene, graphene oxide, carbon nanotubes, and graphene nanoribbons for MOF-based gas separation membranes, particularly focusing on polycrystalline MOF membrane hybridization with graphitic materials. We also briefly discuss the use of carbon/MOF hybrid materials for preparing mixed matrix membranes.

Preclinical studies of a PARP targeted, Meitner-Auger emitting, theranostic radiopharmaceutical for metastatic ovarian cancer

Advanced ovarian cancer currently has few therapeutic options. Poly(ADP-ribose) polymerase (PARP) inhibitors bind to nuclear PARP and trap the protein-inhibitor complex to DNA. This work investigates a theranostic PARP inhibitor for targeted radiopharmaceutical therapy of ovarian cancer in vitro and PET imaging of healthy mice in vivo.

METHODS

[77Br]RD1 was synthesized and assessed for pharmacokinetics and cytotoxicity in human and murine ovarian cancer cell lines. [76Br]RD1 biodistribution and organ uptake in healthy mice were quantified through longitudinal PET/CT imaging and ex vivo radioactivity measurements. Organ-level dosimetry following [76/77Br]RD1 administration was calculated using RAPID, an in-house platform for absorbed dose in mice, and OLINDA for equivalent and effective dose in human.

RESULTS

The maximum specific binding (Bmax), equilibrium dissociation constant (Kd), and nonspecific binding slope (NS) were calculated for each cell line. These values were used to calculate the cell specific activity uptake for cell viability studies. The half maximal effective concentration (EC50) was measured as 0.17 (95 % CI: 0.13-0.24) nM and 0.46 (0.13-0.24) nM for PARP(+) and PARP(-) expressing cell lines, respectively. The EC50 was 0.27 (0.21-0.36) nM and 0.30 (0.22-0.41) nM for BRCA1(-) and BRCA1(+) expressing cell lines, respectively. When measuring the EC50 as a function of cellular activity uptake and nuclear dose, the EC50 ranges from 0.020 to 0.039 Bq/cell and 3.3-9.2 Gy, respectively. Excretion through the hepatobiliary and renal pathways were observed in mice, with liver uptake of 2.3 ± 0.4 %ID/g after 48 h, contributing to estimated absorbed dose values in mice of 19.3 ± 0.3 mGy/MBq and 290 ± 10 mGy/MBq for [77Br]RD1 and [76Br]RD1, respectively.

CONCLUSION

[77Br]RD1 cytotoxicity was dependent on PARP expression and independent of BRCA1 status. The in vitro results suggest that [77Br]RD1 cytotoxicity is driven by the targeted Meitner-Auger electron (MAe) radiotherapeutic effect of the agent. Further studies investigating the theranostic potential, organ dose, and tumor uptake of [76/77Br]RD1 are warranted.

Effective single web-structured electrode for high membrane electrode assembly performance in polymer electrolyte membrane fuel cell

To achieve a sustainable society, CO₂ emissions must be reduced and efficiency of energy systems must be enhanced. The polymer electrolyte membrane fuel cell (PEMFC) has zero CO₂ emissions and high effectiveness for various applications. A well-designed membrane electrolyte assembly (MEA) composed of electrode layers of effective materials and structure can alter the performance and durability of PEMFC. We demonstrate an efficient electrode deposition method through a well-designed carbon single web with a porous 3D web structure that can be commercially adopted. To achieve excellent electrochemical properties, active Pt nanoparticles are controlled by a nanoglue effect on a highly graphitized carbon surface. The developed MEA exhibits a notable maximum power density of 1082 mW/cm² at 80°C, H₂/air, 50% RH, and 1.8 atm; low cathode loading of 0.1 mg_Pt/cm²; and catalytic performance decays of only 23.18 and 13.42% under commercial-based durability protocols, respectively, thereby achieving all desirables for commercial applications.

Microwave-assisted design of nanoporous graphene membrane for ultrafast and switchable organic solvent nanofiltration

Layered two-dimensional materials can potentially be utilized for organic solvent nanofiltration (OSN) membrane fabrication owing to their precise molecular sieving by the interlayer structure and excellent stability in harsh conditions. Nevertheless, the extensive tortuosity of nanochannels and bulky solvent molecules impede rapid permeability. Herein, nanoporous graphene (NG) with a high density of sp² carbon domain was synthesized via sequential thermal pore activation of graphene oxide (GO) and microwave-assisted reduction. Due to the smooth sp² carbon domain surfaces and dense nanopores, the microwave-treated nanoporous graphene membrane exhibited ultrafast organic solvent permeance (e.g., IPA: 2278 LMH/bar) with excellent stability under practical cross-flow conditions. Furthermore, the membrane molecular weight cut-off (MWCO) is switchable from 500 Da size of molecule to sub-nanometer-size molecules depending on the solvent type, and this switching occurs spontaneously with solvent change. These properties indicate feasibility of multiple (both binary and ternary) organic mixture separation using a single membrane. The nanochannel structure effect on solvent transport is also investigated using computation calculations.

Intravascular ultrasound-guided optimization for chronic total occlusion-percutaneous coronary intervention with multiple drug-eluting stents

Background

Multiple stenting in the chronic total occlusion (CTO) lesions is frequently required, however associated with poorer clinical outcomes. It is demonstrated that intravascular ultrasound (IVUS)-guided CTO-percutaneous coronary intervention (PCI) is related to a lower risk of adverse clinical events.

Purpose

We aimed to evaluate the clinical impact of stent optimization under IVUS guidance for multiple stenting, comparing with single stenting.

Methods

A total of 916 patients receiving drug-eluting stent (DES) under IVUS guidance were classified into two groups (stent optimization and non-optimization) according to optimization criteria (an absolute expansion criteria; minimal stent area ≥4.9 mm2 and a relative expansion criteria; 80% of mean reference lumen area). Of total population, 314 patients (34.3%) were treated with single stent and 575 patients (62.7%) were treated with multiple stents, respectively. Ischemic-driven target-lesion revascularization (TLR)/reocclusion was evaluated.

Results

Under IVUS guidance, 316 patients (34.5%) met IVUS criteria for stent optimization The achieving rates were 53% in the single stent group and 24% in the multiple stents group, respectively, (p<0.001). During a median of 4.7 years, the multiple stent group showed a significantly higher TLR/reocclusion rate, compared with the single stent group (12.8% vs. 5.2%, adjusted hazard ratio [HR] 2.51, 95% confidence interval [CI] 1.20–5.25, p=0.01). (Figure 1) Meeting both the absolute and relative expansion criteria was associated with a significantly low rate of TLR/reocclusion rate (12.5% vs. 5.2%, adjusted HR 0.34, 95% CI: 0.15–0.79, p=0.01). Under IVUS-guidance, there was no significant difference between multiple stenting and single stenting in case of achieving the optimization criteria (6.5% vs. 4.2%, p=0.11), whereas non-optimization group in the patients with multiple stenting showed a significantly higher rate of TLR/reocclusion, compared with IVUS-optimization group in the patients with single stenting (14.5% vs. 4.2%, p=0.002). (Figure 2)

Conclusions

In CTO-PCI with DES, multiple stenting significantly increased the risk of TLR/reocclusion. IVUS-guided optimization for multiple stenting showed a comparable long-term risk of TLR/reocclusion to single stenting with IVUS optimization. Hence, achieving IVUS expansion criteria may help to reduce the risk of TLR/reocclusion in CTO-PCI with multiple DES overlapping.

Funding Acknowledgement

Type of funding sources: None.

Sodium-glucose co-transporter-2 inhibitors after acute myocardial infarction in type 2 diabetes patients: a population-based investigation from South Korea

Background

Whether the early use of sodium-glucose co-transporter-2 (SGLT2) inhibitors has cardioprotective effects following acute myocardial infarction (AMI) is unknown.

Purpose

We aimed to evaluate the association between the early initiation of SGLT2 inhibitors and cardiac event rates in diabetes patients with AMI undergoing percutaneous coronary intervention (PCI).

Methods

Based on the National Health Insurance claims data in South Korea, patients aged 18 years or older who had undergone PCI for the diagnosis of AMI between 2014 and 2018 were analyzed. Patients treated with SGLT2 inhibitors or other glucose-lowering drugs were matched based on a propensity score. The primary endpoint was a composite of all-cause mortality and hospitalizations for heart failure (HF). Major adverse cardiac events (MACE; a composite of all-cause death, non-fatal MI, and ischemic stroke) were compared as the secondary endpoint.

Results

After 1:2 propensity score matching, a total of 26,814 patients were assigned to the SGLT2 inhibitors group (938 patients) and the no use of SGLT2 inhibitors group (1,876 patients), respectively. During a median follow-up of 2.1 years, compared to no use of SGLT2 inhibitors, the early use of SGLT2 inhibitors was associated with lower risks of both the primary endpoint (9.8% vs. 13.9%, adjusted hazard ratio [HR] = 0.68, 95% confidence interval [CI]: 0.54 to 0.87, p=0.002) and secondary endpoint (9.1% vs. 11.6%, adjusted HR = 0.77, 95% CI: 0.60 to 0.99, p=0.04) (Figure 1). All-cause mortality and hospitalizations for HF were significantly lower in the early use of SLGT2 inhibitors group (adjusted HR = 0.55; 95% CI: 0.37 to 0.80; p=0.002; and HR = 0.74; 95% CI: 0.56 to 0.98; p=0.03, respectively). The incidence of non-fatal MI and ischemic stroke were not statistically different (Figure 2).

Conclusions

The early use of SGLT2 inhibitors in diabetes patients treated with PCI for AMI was associated with a significantly lower risk of cardiovascular events including all-cause mortality, hospitalizations for HF, and MACE. Our results suggest that the use of SGLT2 inhibitors could expand to the acute phase of AMI survivors with diabetes to reduce mortality and the subsequent development of congestive HF and ischemic events.

Funding Acknowledgement

Type of funding sources: Private hospital(s). Main funding source(s): This work was partly supported by the Research Institute of Medical Science, The Catholic University of Korea, Eunpyeong St. Mary's Hospital, Seoul, Republic of Korea.

Skin manifestations and clinical features of drug reaction with eosinophilia and systemic symptoms (DRESS): A retrospective multicenter study of 125 patients

BACKGROUND

Drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe adverse drug reaction generally accompanied by skin manifestations as the first and most frequent symptoms. However, skin manifestations and associated clinical features of DRESS have not been fully explored and evaluated.

OBJECTIVES

This study aimed to describe the skin manifestations of DRESS in detail and analyze their association with demographic characteristics and extra-cutaneous clinical features.

METHODS

We conducted this retrospective study on patients with DRESS diagnosed between September 2009 and August 2021 at three medical institutes and validated using the RegiSCAR score. Data regarding demographics, skin manifestations, and clinical characteristics were retrieved through thorough chart reviews.

RESULTS

Among 182 potential cases of DRESS, the validated 125 cases were analyzed. A widespread rash extending over more than 50% of the body surface area was observed in 122 patients (97.6%) and typical facial edema was experienced by 67 patients (53.6%). Polymorphous maculopapules were the most common rash morphology (106, 84.8%): specifically, exfoliative (59, 47.2%), urticarial (57, 45.6%), and purpuric forms (39, 31.2%) were common. Mucosal involvement was observed in 41 patients (32.8%). Patients with carboxamide antiepileptics (carbamazepine and oxcarbazepine) experienced more edema (P = .014) and typical facial edema than those with allopurinol (P = .021). The RegiSCAR score was higher in patients with purpura (P < .01).

CONCLUSIONS

Skin manifestations of DRESS exhibit a wide range of skin lesions and can vary according to the culprit drugs. Early suspicion and prompt intervention are needed to improve prognosis.

Graphene Nanoribbon/Carbon Nanotube Hybrid Hydrogel: Rheology and Membrane for Ultrafast Molecular Diafiltration

Hybrids based on carbon nanotubes (CNTs) and graphene nanoribbons (GNRs) are expected to have synergistic effects for various applications. Herein, we demonstrate a simple one-pot synthesis of a CNT/GNR hybrid material by adjusting the oxidation and unzipping conditions of multi-walled CNTs (MWNTs). The MWNT/graphene oxide nanoribbon (GONR) hybrid was dispersed in various solvents, particularly showing the hybrid hydrogel phase in water at a concentration of 40 mg mL^-1. The MWNT/GONR hydrogel exhibited shear-thinning behavior, which can be beneficial for coating a large-area MWNT/GONR layer onto a polymeric porous support by using a scalable slot-die coater. The MWNT/GONR membrane exhibited an outstanding nanofiltration performance, with a molecular weight cutoff of 300 Da and a dye/salt diafiltration performance with a separation factor of 1000 and a water flux of 367.8 LMH, far surpassing the upper bound of diafiltration performance of the existing membranes.

High-aspect ratio zeolitic imidazolate framework (ZIF) nanoplates for hydrocarbon separation membranes

Metal-organic frameworks with high aspect ratios have the potential to yield high-performance gas separation membranes. We demonstrate the scalable synthesis of high–aspect ratio zeolitic imidazolate framework (ZIF)–8 nanoplates via a direct template conversion method in which high aspect ratio–layered Zn hydroxide sheets [Zn₅(NO₃)₂(OH)₈] were used as the sacrificial precursor. Successful phase conversion occurs as a result of the collaboration of low template stability and delayed delivery of 2-methylimidazole in weakly interacting solvents, particularly using acetone. When the ZIF-8 nanoplates with an average aspect ratio of 20 were shear aligned in the 6FDA-DAM polymer matrix by bar coating, the separation performance for propylene/propane far surpassed that of the previously reported mixed matrix and polymeric membranes, showing a propylene permeability of 164 Barrer and selectivity of 33.4 at 40 weight % loadings.

Ultrafast H2-selective nanoporous multilayer graphene membrane prepared by confined thermal annealing

H₂ selective dense pores are generated in a graphene oxide (GO) layer by thermal-decomposition of oxygen-functional groups under high pressure. The nanoporous GO membrane shows H₂/CO₂ selectivity of 12.1 and H₂ permeability of 10360 Barrer.

Large-Area Ti3C2Tx-MXene Coating: Toward Industrial-Scale Fabrication and Molecular Separation

Large-scale fabrication of MXene films is in high demand for various applications, but it remains difficult to meet industrial requirements. In this study, we develop a slot-die coating method for the preparation of large-area MXene membranes. The technique allows the fabrication of continuous and scalable coatings with a rapid coating speed of 6 mm s^-1. The thickness can be readily controlled from the nanometer scale to the micrometer scale, and the alignment of the nanosheet is enhanced by the shear force of the slot-die head. Molecular separation experiments employing a film with a thickness of approximately 100 nm are performed. A nanofiltration performance with water permeance of 190 LMH/bar and molecular weight cutoff of 269 Da is achieved, surpassing previously reported results obtained using MXene-based nanofiltration membranes. The stability of the membrane is highlighted by its nanofiltration performance of 30 days under harsh oxidizing conditions, which is the longest operation ever achieved for a 2D material-based membrane. The extraordinary stability of the film suggests its high potential for industrial and practical applications. The antioxidizing phenomena can be attributed to self-protection of the MXene surface by adsorbed organic molecules, which are particularly stabilized with positively charged molecules via chemisorption.

Computational modeling for antiarrhythmic drugs for atrial fibrillation according to the genotypes

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This work was supported by a grant [HI19C0114] from the Ministry of Health and Welfare. Additionally, the work was funded by grants [NRF-2019R1C1C100907512], and [NRF-2020R1A2B01001695] from the Basic Science Research Program run by the National Research Foundation of Korea (NRF) under the Ministry of Science, ICT & Future Planning (MSIP).

Background

The efficacy of antiarrhythmic drugs (AAD) can vary in patients with atrial fibrillation (AF) and the PITX2 gene affects the responsiveness of AADs. We explored the virtual AAD (V-AAD) responses between wild-type and PITX2+/- deficient AF conditions by realistic in-silico AF modeling.

Methods

We tested the V-AADs in AF modeling integrated with patients’ 3D-computed tomography and 3D-electroanatomical mapping, acquired in 25 patients (68% male, 59.8 ± 9.8 years old, 32.0% paroxysmal type). The ion currents for the PITX2+/- deficiency and each AAD (amiodarone, sotalol, dronedarone, flecainide, and propafenone) were defined based on previous publications.

Results

We compared the wild-type and PITX2+/- deficiency in terms of the action potential duration (APD90), conduction velocity (CV), maximal slope of restitution (Smax), and wave-dynamic parameters, such as the dominant frequency (DF), phase singularities (PS), and AF termination rates according to the V-AADs. The PITX2+/- deficient model exhibited a shorter APD90 (p &lt; 0.001), a lower Smax (p &lt; 0.001), mean DF (p = 0.012), PS number (p &lt; 0.001), and a longer AF cycle length (AFCL, p = 0.011). Five V-AADs changed the electrophysiology in a dose dependent manner. AAD-induced AFCL lengthening (p &lt; 0.001) and reductions in the CV (p = 0.033), peak DF (p &lt; 0.001) and PS number (p &lt; 0.001) were more significant in PITX2+/- deficient than wild-type AF. PITX2+/- deficient AF was easier to terminate with class IC AADs than the wild-type AF (p = 0.018).

Conclusions

The computational modeling-guided AAD test was feasible for evaluating the efficacy of multiple AADs in patients with AF. AF wave-dynamics and electrophysiological characteristics are different among the PITX2 deficient and the wild-type genotype models. BaselineChanges after AADClass ICClass IIIWild-typePITX2+/-p-valueWild-typePITX2+/-p-valueWild-typePITX2+/-p-valueWild-typePITX2+/-p-valueAPD90, (ms)243.7 ± 33.8184.4 ± 15.5&lt;0.00138.2 ± 37.343.4 ± 56.20.223275.9 ± 43.5219.0 ± 39.2&lt;0.001284.9 ± 32.8233.8 ± 71.4&lt;0.001CV, (m/s)0.78 ± 0.320.70 ± 0.210.347-0.15 ± 0.18-0.20 ± 0.260.0330.63 ± 0.320.53 ± 0.300.0270.60 ± 0.360.43 ± 0.33&lt;0.001Mean Smax0.787 ± 0.280.531 ± 0.18&lt;0.0010.005 ± 0.260.115 ± 0.24&lt;0.0010.828 ± 0.310.694 ± 0.320.0030.768 ± 0.320.608 ± 0.27&lt;0.001Mean AFCL, (ms)146.96 ± 24.61164.78 ± 22.730.01122.62 ± 24.5537.92 ± 32.72&lt;0.001165.44 ± 36.96190.85 ± 35.61&lt;0.001169.05 ± 25.26203.35 ± 34.78&lt;0.001Peak DF, (Hz)10.68 ± 2.9711.82 ± 3.340.211-2.98 ± 4.94-5.46 ± 4.66&lt;0.00110.01 ± 4.397.23 ± 4.20&lt;0.0016.30 ± 4.325.80 ± 4.070.301Mean DF, (Hz)6.80 ± 0.886.22 ± 0.710.012-1.95 ± 2.44-2.20 ± 1.990.2065.75 ± 1.784.53 ± 2.00&lt;0.0014.14 ± 2.393.69 ± 2.000.077PS Number, (N)101086 ± 9608814150 ± 24778&lt;0.001-59322 ± 99288-7409 ± 27856&lt;0.00150579 ± 6523611568 ± 21868&lt;0.00132951 ± 558643524 ± 8302&lt;0.001PS Life Span, (ms)109.36 ± 113.90102.24 ± 226.640.889-24.87 ± 72.06-41.38 ± 126.350.073103.36 ± 180.6868.05 ± 162.790.14871.91 ± 141.8655.99 ± 217.970.454Table. Effects of AADs in the Wild-type and PITX2+/- Deficiency groupAbstract Figure. Wild-type vs. PITX2+/- baseline model

Diamine vapor treatment of viscoelastic graphene oxide liquid crystal for gas barrier coating

A layered graphene oxide/ethylenediamine (GO/EDA) composite film was developed by exposing aqueous GO liquid crystal (GOLC) coating to EDA vapor and its effects on the gas barrier performance of GO film were systematically investigated. When a GO/EDA coating with a thickness of approximately 1 μm was applied to a neat polyethylene terephthalate (PET) film, the resultant film was highly impermeable to gas molecules, particularly reducing the gas permeance up to 99.6% for He and 98.5% for H₂ in comparison to the neat PET film. The gas barrier properties can be attributed to the long diffusion length through stacked GO nanosheets. The EDA can crosslink oxygen-containing groups of GO, enhancing the mechanical properties of the GO/EDA coating with hardness and elastic modulus values up to 1.14 and 28.7 GPa, respectively. By the synergistic effect of the viscoelastic properties of GOLC and the volatility of EDA, this coating method can be applied to complex geometries and EDA intercalation can be spontaneously achieved through the scaffold of the GOLC.

Tuning the hierarchical pore structure of graphene oxide through dual thermal activation for high-performance supercapacitor

Herein, we introduce a simple method to prepare hierarchical graphene with a tunable pore structure by activating graphene oxide (GO) with a two-step thermal annealing process. First, GO was treated at 600 °C by rapid thermal annealing in air, followed by subsequent thermal annealing in N₂. The prepared graphene powder comprised abundant slit nanopores and micropores, showing a large specific surface area of 653.2 m²/g with a microporous surface area of 367.2 m²/g under optimized conditions. The pore structure was easily tunable by controlling the oxidation degree of GO and by the second annealing process. When the graphene powder was used as the supercapacitor electrode, a specific capacitance of 372.1 F/g was achieved at 0.5 A/g in 1 M H₂SO₄ electrolyte, which is a significantly enhanced value compared to that obtained using activated carbon and commercial reduced GO. The performance of the supercapacitor was highly stable, showing 103.8% retention of specific capacitance after 10,000 cycles at 10 A/g. The influence of pore structure on the supercapacitor performance was systematically investigated by varying the ratio of micro- and external surface areas of graphene.

Graphene Oxide Nanoribbon Hydrogel: Viscoelastic Behavior and Use as a Molecular Separation Membrane

The preparation of carbon materials based hydrogels and their viscoelastic properties are essential for their broad application and scale-up. However, existing studies are mainly focused on graphene derivatives and carbon nanotubes, and the behavior of graphene nanoribbon (GNR), a narrow strip of graphene, remains elusive. Herein, we demonstrate the concentration-driven gelation of oxidized GNR (graphene oxide nanoribbon, GONR) in aqueous solvents. Exfoliated individual GONRs sequentially assemble into strings (∼1 mg/mL), nanoplates (∼20 mg/mL), and a macroporous scaffold (50 mg/mL) with increasing concentration. The GONR hydrogels exhibit viscoelastic shear-thinning behavior and can be shear-coated to form large-area GONR films on substrates. The entangled and stacked structure of the GONR film contributed to outstanding nanofiltration performance under high pressure, cross-flow, and long-term filtration, while the precise molecular separation with 100% rejection rate was maintained for sub-nanometer molecules.

Evaluation of morphokinetic characteristics of zona pellucida free mouse pre-implantation embryos using time-lapse monitoring system

The mammalian zygote cleaves and develops to blastocyst within the zona pellucida (ZP) in vivo. The presence or absence of ZP may affect the characteristics of the embryo, including blastomere alignment, cell-cell junction, and compaction. This study aimed to compare the morphokinetic characteristics of ZP intact and ZP free mouse pre-implantation embryos with time-lapse monitoring system. Mouse 2-cell embryos were collected 1.5 days post coitum (dpc), and their ZPs were removed by treatment with acid Tyrode's solution. All embryos were cultured in vitro up to the outgrowth stage at 7.5 dpc. In this study, ZP did not influence the cumulative times from 2-cell to further stages and blastulation. Interestingly, ZP free embryos at 4-cell stage have three patterns of blastomere alignment according to the number of contact points between blastomeres. However, blastomere alignment did not lead to any differences in morphokinetic comparisons. Regardless of the presence or absence of ZP, embryos compacted after the 8-cell stage took shorter time to become blastocysts than embryos compacted pre-8-cell stage. Nevertheless, cell-cell junction proteins required for successful compaction were similarly expressed between ZP intact and ZP free embryos. ZP intact embryos compacted post-8-cell stage had higher rate of reaching blastocysts than compacted ZP intact embryos before 8-cell stage while the outgrowth/blastocyst rate was similar. In this study, the presence or absence of ZP did not influence embryonic development and expression of cell surface glycoproteins, whereas compaction timing may be one of the criteria for evaluating embryo quality. ZP free embryos may become an alternative for overcoming cases with ZP problems in a human ART program.

High energy redshifted and enhanced spectral broadening by molecular alignment

We demonstrate an efficient approach for enhancing the spectral broadening of long laser pulses and for efficient frequency redshifting by exploiting the intrinsic temporal properties of molecular alignment inside a gas-filled hollow-core fiber (HCF). We find that laser-induced alignment with durations comparable to the characteristic rotational time scale TRotAlign enhances the efficiency of redshifted spectral broadening compared to noble gases. The applicability of this approach to Yb lasers with (few hundred femtoseconds) long pulse duration is illustrated, for which efficient broadening based on conventional Kerr nonlinearity is challenging to achieve. Furthermore, this approach proposes a practical solution for high energy broadband long-wavelength light sources, and it is attractive for many strong field applications.

Effects of dispersed copper nanoparticles on Ni-ceria based dry methanol fuelled low temperature solid oxide fuel cells

Methanol is an attractive energy source due to its portability and thermodynamic coke resistance by its oxygen content. In order to operate dry methanol fuel low temperature solid oxide fuel cells (LT-SOFCs), it is important to solve the problems of carbon formation and its low performance. In this study, copper impregnation was selected to decrease the carbon deposition and enhance the performance at low temperature. The interaction of copper, ceria and nickel improves CO oxidation capacity which improves coke tolerance and nano-sized nickel copper alloys improved durability and catalytic performance under methanol feed. It markedly amplified the performance about 0.4 W cm⁻² at 550 °C with the durable operation at 1.4 A cm⁻² over 50 h. Loading copper nanoparticles is promising method for Ni-ceria based LT-SOFC using methanol fuel with high performance and stable operation.

Copper impregnation was selected to decrease the carbon deposition and enhance the performance at low temperature of dry methanol fuelled low temperature solid oxide fuel cells.

Selective Ion Transporting Polymerized Ionic Liquid Membrane Separator for Enhancing Cycle Stability and Durability in Secondary Zinc-Air Battery Systems

Rechargeable secondary zinc-air batteries with superior cyclic stability were developed using commercial polypropylene (PP) membrane coated with polymerized ionic liquid as separators. The anionic exchange polymer was synthesized copolymerizing 1-[(4-ethenylphenyl)methyl]-3-butylimidazolium hydroxide (EBIH) and butyl methacrylate (BMA) monomers by free radical polymerization for both functionality and structural integrity. The ionic liquid induced copolymer was coated on a commercially available PP membrane (Celguard 5550). The coat allows anionic transfer through the separator and minimizes the migration of zincate ions to the cathode compartment, which reduces electrolyte conductivity and may deteriorate catalytic activity by the formation of zinc oxide on the surface of the catalyst layer. Energy dispersive X-ray spectroscopy (EDS) data revealed the copolymer-coated separator showed less zinc element in the cathode, indicating lower zinc crossover through the membrane. Ion coupled plasma optical emission spectroscopy (ICP-OES) analysis confirmed over 96% of zincate ion crossover was reduced. In our charge/discharge setup, the constructed cell with the ionic liquid induced copolymer casted separator exhibited drastically improved durability as the battery life increased more than 281% compared to the pure commercial PP membrane. Electrochemical impedance spectroscopy (EIS) during the cycle process elucidated the premature failure of cells due to the zinc crossover for the untreated cell and revealed a substantial importance must be placed in zincate control.

Synthesis and application of hexagonal perovskite BaNiO3 with quadrivalent nickel under atmospheric and low-temperature conditions

A hexagonal perovskite BaNiO3 with unusually high-valence nickel(iv) was synthesized under atmospheric and low-temperature conditions by an ethylenediamine-derived wet-chemical route. Secondary phases disappeared with increase in the pH value, and the single-phase BaNiO3 was successfully synthesized at pH 10. The specific surface area was ∼32 m(2) g(-1), which is significantly enhanced compared to the BaNiO3 (0.3 m(2) g(-1)) synthesized by flux-mediated crystal growth. The BaNiO3 was used as an oxygen-evolution reaction (OER) catalyst, and the specific mass activity was ∼5 times higher than that of the BaNiO3 synthesized by flux-mediated crystal growth. As a result, the ethylenediamine-derived sol-gel synthesis could be a simple technique to prepare crystalline compounds such as perovskites and spinels, with unusually high-valence transition metals.