Self-template-assisted micro-phase segregation in blended liquid-crystalline block copolymers films toward three-dimensional structures.

In-plane mesopatterns derived from block-copolymer (BCP) micro-phase segregation in thin films have attracted much interest in practical applications as well as fundamental research programs. However, phase segregation along the film-normal direction has been less studied. Here, we describe a strategy to concurrently, yet independently, control in-plane micro-phase and out-of-plane macro-phase segregation in multiblended films composed of liquid-crystalline BCPs (LCBCPs), affording spontaneously layered three-dimensional (3D) mesostructures. This strategy relies on sequential liquid crystallization during the cooling process in thermal annealing as follows. The constituent LCBCP with the highest isotropic-transition temperature (Tiso) first liquid-crystallizes and segregates from the other LCBCP mixture remaining in isotropic states to form a noncontaminated layer at the top surface. This preformed LCBCP layer preserves its inherent in-plane pattern and acts as a template guiding the subsequent micro-phase segregations of the other low-Tiso LCBCPs underneath. This self-template-assisted micro-phase segregation (STAMPS) readily provides 3D mesostructures, the potential toward rational material design of which is also demonstrated in water-separation applications.

Tunable Thermal Switch via Order-Order Transition in Liquid Crystalline Block Copolymer.

Organic material-based thermal switch is drawing much attention as one of the key thermal management devices in organic electronic devices. This study aims at tuning the switching temperature (TS) of thermal conductivity by using liquid crystalline block copolymers (BCs) with different order-order transition temperature (Ttr) related to the types of mesogens in the side chain. The BC films with low Ttr of 363 K and high Ttr of 395 K exhibit reversible thermal conductivity switching behaviors at TS of ∼360 K and ∼390 K, respectively. The BC films also exhibit thermal conductivity variation originating from the anisotropy of the internal structures: poly(ethylene oxide) domains and liquid crystals. These results demonstrate that the switching behavior is attributed to an order-order transition between BC films with vertically arranged cylinder domains and the ones with ordered sphere domains. This highlights that BCs become a promising thermal conductivity switching material with tailored TS.

[Clinical Features of Endocrine Disorders with Immune Checkpoint Inhibitor in Patients with Non-Small Cell Lung Cancer].

Immune checkpoint inhibitors(ICIs)could cause immune-related adverse events(irAEs), of which endocrine disorders are relatively common. Symptoms include fatigue, anorexia, and shock, making diagnosis and treatment difficult. This study aimed to analyze the characteristics of patients with non-small cell lung cancer concomitant with endocrine disorders as irAEs. In total, 83 patients who were administered ICIs for advanced or postoperative recurrent non-small cell lung cancer between February 2016 and February 2021 were identified. We retrospectively studied the clinical course and findings of 7 patients who developed endocrine disorders after treatment. Four patients had hypopituitarism, and 3 patients had thyroid dysfunctions. There were 6 male patients and 1 female patient. Regarding anticancer agents, 5 patients received ICI alone, and 2 patients received ICI plus cytotoxic chemotherapies. The patients received treatment from the irAE treatment team in our hospital, and 5 of 7 patients could were able to be readministered ICIs. Endocrine disorders as irAEs require collaboration with specialized departments for early diagnosis and treatment.

Ice/Salt-Assisted Synthesis of Ultrathin Two-Dimensional Micro/Mesoporous Iron and Nitrogen Co-Doped Carbon as an Efficient Electrocatalyst for Oxygen Reduction.

An ice/salt-assisted strategy has been developed to achieve the green and efficient synthesis of ultrathin two-dimensional (2D) micro/mesoporous carbon nanosheets (CNS) with the dominant active moieties of Fe-N4 (Fe-N-CNS) as high-performance electrocatalysts for the oxygen reduction reaction (ORR). The strategy involves freeze-drying a mixture of iron porphyrin and KCl salt using ice as template followed by a confined pyrolysis with KCl as an independent sealed nanoreactor to facilitate the formation of 2D carbon nanosheets, N incorporation, and porosity creation. The well-defined assembly of ultrathin 2D carbon nanosheets ensures high utilization of D1 and D3 Fe-N4 active sites, and effectively promotes the mass transport of ORR reactants by virtue of the pronounced mesoporous structure. The resulting Fe-N-CNS electrocatalyst was shown to exhibit superior ORR activity, better electrochemical durability, and methanol tolerance towards ORR in alkaline electrolyte relative to the commercial Pt/C electrocatalyst.

Helical micromotor operating under stationary DC electrostatic field.

The direct current (DC) motor is a rotary device that converts DC electrical energy into mechanical energy. However, it is known that, in downsizing the currently available macromotor, rotary motion of DC micromotors cannot work well due to the larger viscous effect. Here, we report simple DC micromotors working under a new principle. We previously revealed that in an oil phase containing an ionic surfactant, non-spherical particles exhibit various types of regular motions such as spinning and circular orbital motions. In this study, we found that a microhelix exhibits a new type of periodic motion, namely, the cork-screw-type rotation, in a specific direction depending on the material of the helix, metal or non-metallic organics. The results show that a left-handed nickel helix rotates in the clockwise direction when viewed from the positive electrode, whereas an organic one rotates in the opposite direction (anti-clockwise) under the same electrode arrangement with stationary constant DC voltage. In addition, we demonstrate that the cork-screw rotation is switched to opposite direction by changing the handedness (chirality). It is to be noted that the micromotors reported here maintain their stable motion without any mechanical support such as rotational axes or electronic switching devices. The invented DC micromotor would be applicable for mechanical and fluidic devices, being useful as a smart device in microrobots and microfluidics.

Electrostatic Repulsion-Induced Desorption of Dendritic Viologen-Arranged Molecules Anchored on a Gold Surface through a Gold-Thiolate Bond Leading to a Tunable Molecular Template.

We investigated the adsorption and desorption behavior of self-assembled monolayers (SAMs) on gold derived from dendritic viologen-arranged molecules with an ω-mercaptodecyl group (A n, n (dendritic generation) = 0-3) at the apex of the dendritic structure in polar solvents. The adsorption of the dendritic molecules occurred quickly and saturated within a few minutes in an acetonitrile/ethanol (1/1, v/v) mixture at a concentration of 2 mM. Atomic force microscopy images of the SAMs showed flat surfaces regardless of the dendritic generation because the peripheral viologen units were closely packed at the surface of the molecular layer. Individual A3 molecules immobilized on the substrate were observed by scanning tunneling microscopy measurements of a mixed SAM with decanethiol. The desorption behaviors of dendritic molecules from the A n-SAMs in several solvents such as water were also investigated. The spontaneous desorption of the A n-SAM occurred more rapidly than that of a conventional n-alkanethiol SAM. However, the desorption was inhibited by adding electrolytes such as NaNO3 due to the shielding effect on the electrostatic repulsion between the dendritic molecules. These results indicate that the surface density of the dendritic molecules can be controlled through the desorption.

Nanoporous Films with Sub-10 nm in Pore Size from Acid-Cleavable Block Copolymers.

Nanoporous thin films with pore size of sub-10 nm are fabricated using an acid-cleavable block copolymer (BCP), a benzoic imine junction between poly(ethylene oxide) (PEO) and poly(methacrylate) (PMAAz) bearing an azobenzene side chain (denoted as PEO-bei-PMAAz) as the precursor. After a thermal annealing, the block copolymers are self-assembled to form highly ordered PEO cylinders within a PMAAz matrix normal to the film, even in the case of low BCP molecular weight due to the existing of the liquid crystalline (LC) azobenzene rigid segment. Thus, PMAAz thin films with pore size of ≈7 nm and density of ≈1012 cm-2 are obtained after removal of the PEO minor phase by breaking the benzoic imine junction under mild acidic conditions. This work enriches the nanoporous polymer films from BCP precursors and introduces the LC property as a functionality which can further enhance the mechanical properties of the films and broaden their applications.

Water-Rich Fluid Material Containing Orderly Condensed Proteins.

A fluid material with high protein content (120-310 mg mL-1 ) was formed through the ordered self-assembly of native proteins segregated from water. This material is instantly prepared by the simple mixing of a protein solution with anionic and cationic surfactants. By changing the ratio of the surfactants based on the electrostatic characteristics of the target protein, we observed that the surfactants could function as a versatile molecular glue for protein assembly. Moreover, these protein assemblies could be disassembled back into an aqueous solution depending on the salt conditions. Owing to the water-retaining properties of the hydrophilic part of surfactants, the proteins in this material are in a water-rich environment, which maintains their native structure and function. The inclusion of water also provides functional extensibility to this material, as demonstrated by the preparation of an enzymatically active gel. We anticipate that the unique features of this material will permit the use of proteins not only in solution but also as elements of integrated functionalized materials.

[Comparison of the Cost-Effectiveness of the SOX and COX Regimens in Patients with Unresectable Advanced and Recurrent Colorectal Cancer Using a Clinical Decision Analysis Approach].

Phase III clinical trials have comfirmed that the S-1 plus oxaliplatin(SOX)is inferior to the capecitabine plus oxaliplatin (COX)regimen in the treatment of metastatic colorectal cancer.On the basis of these findings, we compared, using a clinical decision analysis-based approach, the cost-effectiveness of the SOX and COX regimens.Herein, we simulated the expected effects and costs of the SOX and COX regimens using the markov model.Clinical data were obtained from Hong's 2012 report.The cost data comprised the costs for pharmacist labor, material, inspection, and treatment for adverse event, as well as the total cost of care at the advanced stage.The result showed that the expected cost of the SOX and COX regimen was 1,538,330 yen, and 1,429,596 yen, respectively, with an expected survival rate of 29.18 months, and 28.63 months, respectively.The incremental cost-effectiveness ratio of the SOX regimen was 197,698 yen/month; thus, the SOX regimen was found to be more cost-effective that the COX regimen.

Metal nanodot arrays fabricated via seed-mediated electroless plating with block copolymer thin film scaffolding.

We present an alternative approach to fabricating hexagonally arranged nanodot arrays of various metals by seed-mediated electroless plating with a cylinder-forming block copolymer thin film, PEO-b-PMA(Az), as a scaffold. Metal ions were selectively incorporated into PEO cylinders, followed by their reduction to metal and the etching of the scaffold to obtain highly ordered seed arrays of Au, Pd, and Pt. Nanodot arrays of the target metals (Au, Ag, and Ni) were selectively grown on the seed with their highly ordered arrangement by electroless plating. We studied the fabrication processes' suitability for control of the nanodot array size, as well as the plasmonic properties thereof.

Reversible Size Control of Liquid-Metal Nanoparticles under Ultrasonication.

This paper describes the reversible control of the size of liquid-metal nanoparticles under ultrasonication. Gallium was utilized as a liquid metal, which has a melting point of 29.8 °C. Investigating the effects of ultrasonication (power, time, and temperature) on the formation of gallium nanoparticles revealed that the process is similar to the formation of oil in water (O/W) or water in oil (W/O) emulsions, as the temperature significantly affects the size of the gallium nanoparticles (GaNPs). Under ultrasonication, the balance between the break-up and coalescence of the GaNPs can be adjusted by changing the temperature or adding acid through modulating the natural surface oxide layer (which can be removed with acid) and the stabilizing effect of the surfactant dodecanethiol. Coalescence was predominant at higher temperatures, whereas particle break-up was found to be predominant at lower temperatures. Furthermore, the change in size was accompanied by a shift in the plasmonic absorption of the GaNPs in the UV region.

Transition-metal-free controlled polymerization of 2-perfluoroaryl-5-trimethylsilylthiophenes.

A catalytic amount of fluoride anion promoted the polymerization of 2-pentafluorophenyl-5-trimethylsilylthiophene, providing a high-molecular-weight conjugated polymer in a chain-growth-like manner. The resulting polymer with a controlled molecular weight and a low molecular weight distribution was obtained in a high yield. The mechanism involves a pentacoordinated fluorosilicate as a key intermediate. The active polymerization end also initiated the second polymerization to afford well-defined block copolymers.

[Clinical evaluation of lapatinib therapy in metastatic breast cancer using the Bayes meta-analysis].

The efficacy of treatments involving lapatinib for patients with metastatic breast cancers was evaluated in a Bayesian metaanalysis of published data from randomized controlled clinical trials. Four randomized controlled trials including 2,708 patients met the inclusion criteria. Among these patients, 568 were positive for the human epidermal growth factor receptor 2(HER2). The clinical benefit rate(CBR)for HER2-positive patients was the primary outcome of the analysis, and the overall survival(l OS) and the number needed to treat(NNT)were the secondary outcomes of the reported meta-analysis. The Bayesian metaanalysis was conducted according to the Markov-chain Monte-Carlo technique in WinBUGS. The CBR for HER2-positive patients was significantly improved(odds ratio[OR]: 2.281, 95% confidence interval[CI]: 1.490-3.628), whereas no statistically significant improvement was seen in the overall patient CBR(OR: 1.559, 95% CI: 0.768-3.238). The OS hazard ratio (HR)and NNT for the CBR were also estimated for HER2-positive patients. The difference in the OS HR was not statistically significant(HR: 0.789, 95% CI: 0.556-1.086)for HER2-positive patients. The improvement in the NNT for the CBR was statistically significant(NNT 5.164, 95% CI: 3.803-8.723)for HER2-positive patients.

Conjugated polymer chains confined in vertical nanocylinders of a block-copolymer film: preparation, characterization, and optoelectronic function.

Hybrid materials composed of phase-separated block copolymer films and conjugated polymers of the phenylenevinylene family (PPV) are prepared. The PPV chains are embedded in vertical cylinders of nanometer diameter in the block-copolymer films. The cylinders span continuously the whole film thickness of 70 nm. Incorporation of the PPV chains into the one-dimensional cylinders leads to modified photoluminescence spectra and to large absorption anisotropy. The hybrid films show electroluminescence from the PPV chains in a simple light-emitting device at minute doping concentrations, and also exhibit a factor of 19 increase in electron transport efficiency along the single PPV chains.

Doublet or Triplet Antiemetic Prophylaxis for Nausea and Vomiting Induced by Trastuzumab Deruxtecan: an Open-Label, Randomized, and Multicenter Exploratory Phase 2 Study.

Background: Trastuzumab deruxtecan is classified as an anticancer agent that poses a moderate emetic risk in the international guidelines for antiemetic therapy. The guidelines recommend emesis prophylaxis using a two-drug combination therapy comprising a 5-hydroxytryptamine-3 receptor antagonist (5-HT3RA) and dexamethasone (DEX). However, the high incidence of nausea and vomiting associated with trastuzumab deruxtecan is problematic. The National Comprehensive Cancer Network guideline version 1.2023 classified trastuzumab deruxtecan as having a high risk of emesis and changed its recommendation to a triplet regimen including a neurokinin-1 receptor antagonist (NK1RA). However, the emetogenic potential of trastuzumab-deruxtecan and the optimal antiemetic prophylaxis are controversial. Hence, this exploratory phase 2 study aimed to assess the efficacy and safety of treatment comprising 5-HT3RA and DEX with or without a NK1RA in preventing trastuzumab deruxtecan-induced nausea and vomiting. Methods: We conducted an open-label and randomized exploratory phase 2 study at 14 centers in Japan. Patients with breast cancer who were scheduled to receive trastuzumab deruxtecan were enrolled in this study. The patients were randomly assigned to receive granisetron and DEX (arm GD) or granisetron, DEX, and aprepitant (fosaprepitant; arm GDA). The primary endpoint was complete response (CR; no emesis or no rescue therapy) during the overall phase (120 h after the start of trastuzumab deruxtecan). Results: Between September 2020 and March 2023, 40 patients were randomly assigned to the GD (n = 19) or GDA (n = 21) arm. In the GDA arm, one patient who did not complete the use of the rescue medication listed in the diary was excluded from the efficacy analysis, which included the use of rescue medication. The CR rates during the overall phase were 36.8% and 70.0% in the GD and GDA arms, respectively (odds ratio 0.1334; 95% confidence interval [CI]: 0.0232-0.7672; P = 0.0190), with a difference of 33.2%. No grade 3 or 4 toxicity related to antiemetic therapy was observed. Conclusions: Patients receiving trastuzumab deruxtecan require triple therapy, including mandatory NK1RA administration.

Photoelectrode characteristics of partially hydrolyzed aluminum phthalocyanine chloride/fullerene C60 composite nanoparticles working in a water phase.

Photoelectrochemical measurements were used to study the photoelectrode characteristics of composite nanoparticles composed of fullerene C60 and partially hydrolyzed aluminum phthalocyanine chloride (AlPc). In cyclic voltammetry measurements, the electrodes coated with the composite nanoparticles were found to have photoanodic [electron donor: 2-mercaptoethanol (ME)] and photocathodic (electron acceptor: O2) characteristics similar to those of the vapor-deposited p/n junction electrode. Their photoanodic features were further investigated with respect to the transient photocurrent response to light irradiation and the dependence on ME concentration (under potentiostatic conditions), from which it was noted that there was a decrease in the initial spiky photocathodic current and saturation of the steady-state photoanodic current at a higher ME concentration. Thus, the reaction kinetics was probably dominated by charge transport process. Moreover, external and internal quantum efficiency spectrum measurements indicated that the composite nanoparticles responded to the full spectrum of visible light ( < 880 nm) for both the photoanodic and photocathodic current. The present research will assist comprehension of photocatalytic behavior of the composite nanoparticles.

Solvent induced formation of an ordered nanorod array of gold/polymer composite by block copolymer film templating.

We report a novel method to fabricate ordered arrays of gold-polymer composite nanorods with the orientation in the vertical direction using block copolymer (BCP) film. The salt precursor is selectively infiltrated within vertically aligned cylindrical domains of the BCP film by immersing the template in a simple aqueous solution of HAuCl(4). Scanning electron microscopy suggests that the salt might be uniformly positioned along the polymeric cylinders. A subsequent vacuum ultraviolet light irradiation simultaneously reduces the HAuCl(4) into spherical gold nanoparticles with mean diameter around 2 nm and removes the matrix of the BCP template to produce metal-polymer composite nanorods. While the solvent is methanol, the salt might be concentrated at the bottom of the BCP film. As a result, a periodic pattern of gold nanoparticles with average diameter around 11 nm is formed where the BCP film is completely etched away. The solvent can effectively tune the spatial distribution of the salt precursor along the polymeric cylinders, which is responsible for the different morphologies of the photochemically fabricated nanostructures.

Self-organized formation and self-repair of a two-dimensional nanoarray of Ge quantum dots epitaxially grown on ultrathin SiO2-covered Si substrates.

Two-dimensional nanoarrays of Ge quantum dots (QDs) with the ability to self-repair were epitaxially grown by self-organization on Si substrates using an ultrathin SiO(2) film technique. Nanometer-sized voids were patterned on ultrathin SiO(2) films by transcription of the pattern of block copolymer films using a selective etching method and worked as nucleation sites for QD growth. The epitaxial QDs were elastically strain-relaxed without misfit dislocations and of uniform size. The epitaxial structures of Si-capped QD nanoarrays exhibited strong photoluminescence near 1.5 microm.

Vibrational Cooling in Oligomeric Viologens of Different Sizes and Topologies.

Vibrational cooling was investigated in a set of homologous dimers and trimers with methyl viologen repeat units (MV2+). The rapid, <500 fs decay of the D1 excited state of monoreduced viologen (MV+•) via a conical intersection allows the preparation of a vibrationally hot D0 ground state with a large excess energy of 1.7 eV, which is equivalent to the initial effective temperature of ∼800 K. Pump-probe spectroscopy was used to monitor the disappearance of the characteristic D0 → D1 hot absorption band, which appears at longer wavelengths than the steady-state spectrum of "cold" MV+• in equilibrium with the solvent. It is assumed that the vibrational excitation of the ground is initially confined to the same monoreduced viologen repeat unit, which was optically excited to the localized electronic D1 state, although some degree of redistribution may occur already in the excited state. The observed cooling rates depend on the size and topology of the oligomer, with the linear trimer exhibiting significantly faster thermalization than the branched one. The experimental results were corroborated by molecular dynamics simulations carried out in the harmonic approximation. The dynamics of the thermal equilibration in these systems appears to be consistent with primarily ballistic initial propagation of the vibrational excess energy over distances as large as ∼4 nm and suggests the presence of interference between the equivalent pathways in the branched trimer.

Terahertz emission from gold nanorods irradiated by ultrashort laser pulses of different wavelengths.

Electron photoemission and ponderomotive acceleration by surface enhanced optical fields is considered as a plausible mechanism of terahertz radiation from metallic nanostructures under ultrafast laser excitation. To verify this mechanism, we studied experimentally terahertz emission from an array of gold nanorods illuminated by intense (~10-100 GW/cm2) femtosecond pulses of different central wavelengths (600, 720, 800, and 1500 nm). We found for the first time that the order of the dependence of the terahertz fluence on the laser intensity is, unexpectedly, almost the same (~4.5-4.8) for 720, 800, and 1500 nm and somewhat higher (~6.6) for 600 nm. The results are explained by tunneling currents driven by plasmonically enhanced laser field. In particular, the pump-intensity dependence of the terahertz fluence is more consistent with terahertz emission from the sub-cycle bursts of the tunneling current rather than with the ponderomotive mechanism.