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Background: The ELDERCARE-AF trial demonstrated that low-dose edoxaban prevented stroke or systemic embolism (SE) in very elderly Japanese patients with non-valvular atrial fibrillation (NVAF) in whom standard oral anticoagulant therapy was inappropriate because of high bleeding risk. The aim of this study was to elucidate the characteristics and outcomes of such patients in routine clinical practice. Methods and Results: Data were extracted from the Fushimi AF Registry for ELDERCARE-eligible NVAF patients aged ≥80 years, with a CHADS2 score ≥2 and ≥1 bleeding risk factors, as shown in the ELDERCARE-AF trial. ELDERCARE-eligible patients (n=549; 12.8% of the entire cohort, 52.9% of those aged ≥80 years and with CHADS2 score ≥2) were less often male, were older, had more comorbidity and higher risk scores than non-eligible patients from the entire cohort (n=3,734). The crude incidence (% per patient-year) of adverse events was significantly higher in ELDERCARE-eligible than non-eligible patients (stroke/SE, 4.8% vs. 2.0%; major bleeding, 3.6% vs. 1.9%; all-cause mortality, 15.5% vs. 3.9%; cardiovascular death, 2.7% vs. 0.6%; all log-rank P

A disintegrin and metalloproteinase 17 (ADAM17) is a zinc-dependent enzyme that catalyzes the cleavage of the extracellular domains of various transmembrane proteins. ADAM17 is regarded as a promising drug target for the suppression of various diseases, including cancer metastasis. We synthesized a new ADAM17 inhibitor, SN-4, composed of a zinc-binding dithiol moiety and an appendage that specifically binds to a pocket of ADAM17. We show that SN-4 inhibits the ability of ADAM17 to cleave tumor necrosis factor α (TNF-α) in vitro. This activity was reduced by the addition of zinc, indicating the importance of the zinc chelating dithiol moiety. Inhibition of TNF-α cleavage by SN-4 in cells was also observed, and with an IC50 of 3.22 µM, SN-4 showed slightly higher activity than the well-studied ADAM17 inhibitor marimastat. Furthermore, SN-4 was shown to inhibit cleavage of CD44 by ADAM17, but not by ADAM10, and to suppress cell invasion. Molecular docking showed good fitting of the specificity pocket-binding group and one SH of SN-4 and hinted at possible means of structural optimization. This study provides clues for the development of potent and selective ADAM17 inhibitors.

Background/Aim: Tumor cell destruction by boron neutron capture therapy (BNCT) is attributed to the nuclear reaction between (10)B and thermal neutrons. The accumulation of (10)B atoms in tumor cells without affecting adjacent healthy cells is crucial for effective BNCT. We previously reported that several types of liposomal boron delivery systems (BDS) delivered effective numbers of boron atoms to cancer tissues, and showed tumor-growth suppression after thermal neutron irradiation. In the present study, we examined the effects of BNCT after intra-arterial infusion of (10)B-borono-dodecaborate ((10)BSH) by liposomal BDS in rabbit hepatic cancer models. Materials and Methods: We prepared (10)BSH-entrapped transferrin-conjugated polyethylene glycol liposomes constructed with distearoyl-boron lipid (TF-PEG-DSBL), and performed thermal neutron irradiation at the Kyoto University Institute for Integrated Radiation and Nuclear Science after intra-arterial infusion into rabbit VX-2 hepatic tumors. Results: Concentrations of (10)B in VX-2 tumors on delivery with TF-PEG-DSBL liposomes reached 25 ppm on day 3 after the injection. Tumor growth was suppressed by thermal neutron irradiation after intra-arterial injection of this (10)BSH-containing liposomal BDS, without damage to normal cells. Conclusion: The present results demonstrate the applicability of (10)B-containing TF-PEG-DSBL liposomes as a novel intra-arterial boron carrier in BNCT for cancer.

Effective cleaning of a wound promotes wound healing and favours wound care as it can prevent and control biofilms. The presence of biofilm is associated with prolonged wound healing, increased wound propensity to infection, and delayed wound closure. Anionic potassium salts of fatty acids are tested with commonly used anionic surfactants, such as sodium laureth sulphate (SLES) and sodium lauryl sulphate/sodium dodecyl sulphate (SLS/SDS). The normal human dermal cells demonstrated significantly greater viability in fatty acid potassium, including caprylic acid (C8), capric acid (C10), lauric acid (C12), oleic acid (C18:1), and linoleic acid (C18:2), than in SLES or SLS after a 24‐hour incubation. Cytotoxicity by LDH assay in a 5‐minute culture in fatty acid potassium was significantly lower than in SLES or SLS. in vitro wound healing of human epidermal keratinocytes during the scratch assay in 24‐hour culture was more significantly improved by fatty acid treatment than by SLES or SLS/SDS. In a live/dead assay of human epidermal keratinocytes, C8K and C18:1K demonstrated only green fluorescence, indicating live cells, whereas synthetic surfactants, SLES and SLS, demonstrated red fluorescence on staining with propidium iodide, indicating dead cells after SLES and SLS/SDS treatment. Potassium salts of fatty acids are useful wound cleaning detergents that do not interfere with wound healing, as observed in the scratch assay using human epidermal keratinocytes. As potassium salts of fatty acids are major components of natural soap, which are produced by natural oil and caustic potash using a saponification method, this may be clinically important in wound and peri‐wound skin cleaning. In human chronic wounds, natural soap containing fatty acid potassium increased tissue blood flow based on laser speckle flowgraphs after 2 weeks (P

The surface freezing transition of a mixed adsorbed film containing cetyltrimethylammonium chloride (CTAC) and n-hexadecanol (C16OH) was utilized at the dodecane-water interface to control the stability of oil-in-water (O/W) emulsions. The corresponding surface frozen and surface liquid mixed adsorbed films were characterized using interfacial tensiometry and X-ray reflectometry. The emulsion samples prepared in the temperature range of the surface frozen and surface liquid phases showed a clear difference in their stability: the emulsion volume decreased continuously right after the emulsification in the surface liquid region, while it remained constant or decreased at a much slower rate in the surface frozen region. Compared to the previously examined CTAC-tetradecane mixed adsorbed film, the surface freezing temperature increased from 9.5 to 25.0 °C due to the better chain matching between CTAC and C16OH and higher surface activity of C16OH. This then renders such systems much more attractive for practical applications.

Morphological control of C60 fullerene using liquefied porphyrins (1 and 2) as the host matrices was explored. Slow evaporation of the solvent of the equimolar mixture of porphyrin and C60 in toluene afforded the porphyrin/C60 composite with a 3:1 molar ratio. The stoichiometric binding behaviors suggest that specific porphyrin-C60 interactions operate the formation of the porphyrin/C60 composites, as corroborated by spectroscopic and thermal properties, and glazing-incidence wide-angle X-ray diffraction. Under the bulk conditions, the conventional thermodynamic advantage of multiple binding cooperativity for molecular recognition is unlikely to explain the stoichiometric binding behaviors. Instead, we propose a size-matching effect on the porphyrin-C60 interaction in the bulk porphyrin matrices, i.e., "supramolecular solvation". The glassy nature of the porphyrin matrices was transmitted to C60 through the specific interaction, and the porphyrin/C60 composites adopted glassy states at room temperature.

Inspired by the natural spinning process, we developed an aqueous wet spinning system using a citrate buffer with polyethylene glycol (PEG), where the citrate buffer served for ion exchange and acidification and the PEG functioned for dehydration. This biomimetic condition induced the formation of solid fibers with a core–shell structure. The PEG layer could be subsequently removed by the equipped water bath, resulting in amorphous silk fibers. Due to the amorphous state, the silk fibers could be stretched at up to 12 times the original reel speed. Eventually, the mechanical properties featured an extraordinary extension of ~100% and a toughness of ~70 MJ/m3. The crystalline state of the resultant fibers was characterized by synchrotron WAXS to determine the degree of crystallinity and orientation of the beta-sheet structure. Interestingly, the citrate buffer-mediated spinning system enabled tuning of the induction of crystallization by changing the citrate buffer concentrations and coagulation time. The current amorphous spinning of regenerated silk fibers provided in-depth insights into the green and sustainable fabrication of artificial capture-silk-like fibers with unique extensibility and toughness. Inspired by the natural spinning process, we developed an aqueous spinning system with a citrate/polyethylene glycol buffer for highly extensible silk fibers. This system enabled tuning of the induction of crystallization through the buffer conditions.

Cold-stressed leaves possess an elevated risk of photodamage due to an inefficient photosynthetic apparatus during winter conditions. Recovery of cold-stressed coffee seedlings treated with different concentrations of nitrogen applied as foliar urea sprays [control (0), 5, 10, 20, and 40 mM], was investigated under optimum growth chamber conditions (25/20°C) for three months. Concentrations of nitrogen and photosynthetic pigments in the leaves increased with increasing concentration of the foliar sprays up to 20 mM. This was accompanied with a recovery of the photosynthetic apparatus and increased net carbon assimilation rate. In addition, 10 and 20 mM-treated plants also had the highest maximal efficiency of PSII compared to their lower or higher nitrogen concentration treated counterparts. Conversely, these plants contained lower concentrations of 5-caffeoylquinic acid, mangiferin, trigonelline, and caffeine than control plants. We concluded therefore that foliar sprays of the appropriate nitrogen concentration were adequate for recuperating the photosynthetic apparatus and improved the photosynthetic performance of the cold-stressed coffee seedlings.

Because acellular vascular xenografts induce an immunological reaction through macrophage infiltration, they are conventionally crosslinked with glutaraldehyde (GA). However, the GA crosslinking reaction inhibits not only the host immune reaction around the graft but also the graft's enzymatic degradability, which is one of the key characteristics of acellular grafts that allow them to be replaced by host tissue. In this study, we used an 8-arm polyethylene glycol (PEG) to successfully suppress macrophage infiltration, without eliminating graft degradation. Decellularized ostrich carotid arteries were modified with GA or N-hydroxysuccinimide-activated 8-arm PEG (8-arm PEG-NHS), which has a molecular weight of 17 kDa. To evaluate the enzymatic degradation in vitro, the graft was immersed in a collagenase solution for 12 hr. The 8-arm PEG-modified graft was degraded to the same extent as the unmodified graft, but the GA-modified graft was not degraded. The graft was transplanted into rat subcutaneous tissue for up to 8 weeks. Although CD68-positive cells accumulated in the unmodified graft, they did not infiltrate into either modified graft. However, the GA-modified grafts calcified, but the 8-arm PEG-modified graft did not calcify after transplantation. These data suggested that 8-arm PEG-NHS is a promising modification agent for biodegradable vascular xenografts, to suppress acute macrophage infiltration only.

Poly(amino acids) such as polypeptides and proteins are attractive biomass-based polymers that potentially contribute to circular economy for plastic. In the current study, we synthesized polypeptides containing periodic nylon units to incorporate thermal plasticity into polypeptides. We successfully synthesized polypeptides containing nylon units by chemoenzymatic polymerization. In addition to nylon 4, which is of biomass origin, nylon 3, nylon 5, and nylon 6 were chosen as the second monomer units with alanine, a natural amino acid. The synthesized polypeptides showed partial melting behavior prior to their thermal degradation. It was found that the nylon unit length significantly changed the thermal properties of the resulting polypeptides, as evidenced by WAXS and DSC analysis. Furthermore, the biodegradability and environmental toxicity of the synthesized polypeptides were evaluated using biological systems. The copolymer containing nylon 4 is considered as a highly potential biopolymer in terms of the polymerization results and environmental toxicity. These results open a new door for utilizing nylon-containing peptides as biomaterials, especially as thermally processable and eco-friendly structural materials.

A transimpedance amplifier (TIA)—with gamma-irradiation resistance of over 1 MGy—based on a novel 4H-SiC complementary MOS (CMOS) technology was fabricated. This TIA is robust enough to be applied in measuring instruments installed in nuclear power plants or other harshly irradiated environments. The SiC CMOS transistors comprising the TIA feature a thin (8-nm-thick) gate oxide to reduce the threshold-voltage shift ( ${V}_{{\text {th}}}$ ) due to irradiation by more than 90% compared with that of the conventional transistors. Oxynitride protection formed at the SiC–SiO2 interface in the thin gate-oxide region suppresses the deterioration of mobility by interface traps generated by the gamma radiation. The TIA consisting of these SiC-CMOS transistors operated properly up to at least 1.2 MGy without an increase in the offset voltage, although its open-loop gain was degraded due to deteriorated mobility of the p-channel metal–oxide–semiconductor field-effect transistor (MOSFET). On the other hand, increasing the drain leakage current in the nonactive region impeded further improvement of the SiC TIA under a high integral dose. To decrease the drain leakage current, a structure with a high doping concentration layer between the source and the drain in the nonactive region was fabricated. The structure stops the parasitic transistor turning on and the trap-assisted current increasing. The leakage current of the improved structure is about 42% lower than that of a conventional structure.

We designed an amphiphilic block copolymer, poly(methyl methacrylate)-block-poly[oligo(2-ethyl-2-oxazoline) methacrylate] (PMMA-b-P[O(Ox)MA]), suitable for bioinert coating. Angular-dependent X-ray...

OBJECTIVE: Hand hygiene using either 4% chlorhexidine gluconate (CHG) or natural soap during hand rubbing, followed by alcohol-based 1% CHG sanitizer lotion in the operating room was compared to assess bacterial reduction, skin moisture, skin texture, and hand hygiene using qualitative questionnaires. APPROACH: A crossover study with 36 professional scrub nurses at two medical centers was performed to compare 4% CHG followed by alcohol-based 1% CHG sanitizer lotion, the Two-stage method with handwashing using natural soap followed by alcohol-based 1% CHG sanitizer lotion, and the Waterless method, after a period of 10 days of use. The study completely followed CONSORT, www.consort-statement.org. RESULTS: There was no significant difference in bacterial reduction based on the bacterial colony-forming units between the two methods. The skin moisture and skin roughness scores were not significantly different between the two methods. The Waterless method was significantly better than the Two-stage method regarding “foaming,” “quality,” “longevity” (p

Purpose: To evaluate the usefulness of combined treatment with both continuous administration of a hypoxic cytotoxin, tirapazamine (TPZ) and mild temperature hyperthermia (MTH) in boron neu...

Polypeptides containing periodic aromatic residues in their main chains were synthesized via papain-catalyzed chemoenzymatic polymerization of tripeptide ester monomers under moderate conditions in aqueous buffers. As the monomer, 4-aminobenzoic acid (Abz) was modified with Gly or Ala at the N- and C-termini to mitigate the poor substrate specificity of papain to unnatural amino acids. The tripeptide esters, namely, GlyAbzGly and AlaAbzAla ethyl esters, can be recognized and polymerized by papain, resulting in the polypeptides poly(GlyAbzGly) and poly(AlaAbzAla), respectively, with periodic sequences containing Abz units every three residues. Copolymerization of tripeptide esters with Gly or Ala ethyl ester also proceeded in the presence of papain. The secondary structures of the Abz-containing polypeptides were investigated by IR and wide-angle X-ray diffraction (WAXD) analysis. The WAXD profile of poly(GlyAbzGly) was similar to that of polyGly, whereas poly(AlaAbzAla) adopted a sheet-like structure similar to the β-sheet of polyAla. Thermal analysis of Abz-containing polypeptides revealed that the high thermal stability of the Abz-containing polypeptides is related to the distinct sequences that periodically include Abz residues. Polypeptides containing periodic aromatic residues, 4-aminobenzoic acid (Abz), in their main chains were synthesized via papain-catalyzed chemoenzymatic polymerization of tripeptide ester monomers under moderate conditions in aqueous buffers. The secondary structures of the Abz-containing polypeptides were investigated by IR and wide-angle X-ray diffraction analysis. The WAXD profile of poly(GlyAbzGly) was similar to that of polyGly, whereas poly(AlaAbzAla) adopted a sheet-like structure similar to the β-sheet of polyAla.

The quinoxalineimide (QI) unit, containing the electron-withdrawing quinoxaline and imide groups, is an electron-deficient building block for organic semiconductor materials. In this study, three fluorinated or chlorinated QIs (QI-1F, QI-2F, and QI-2Cl), have been designed and developed. We report the impact of the fluorination or chlorination of the QI unit on the electronic structures and charge carrier transport properties as compared to unsubstituted QI (QI-2H) bearing the same n-hexyl side chains. The frontier molecular orbital energy levels downshifted with the incorporation of fluorine or chlorine atoms onto the π-framework of QI. Single-crystal structure analyses revealed that all QI-based molecules have an entirely planar backbone and are packed into two-dimensional slipped stacks with diagonal electronic coupling that enables two-dimensional charge carrier transport. Notably, the doubly fluorinated or chlorinated QIs formed compact molecular packing in the single-crystal structures through an infinite intermolecular network relative to unsubstituted QI (QI-2H). The field-effect transistor-based QI molecules exhibited typical n-channel transport properties. As compared to unsubstituted QI (QI-2H), the chlorinated QI exhibited improved electron mobilities up to 7.1 × 10−3 cm2 V−1 s−1. The threshold voltages of the fluorinated or chlorinated QI devices were clearly smaller than that of QI-2H, which reflects the lowest unoccupied molecular orbital levels of the molecules. This study demonstrates that the fluorinated or chlorinated QIs are versatile building blocks in creating n-channel organic semiconductor materials.

We developed new 10 B carriers for boron neutron capture therapy (BNCT) that can effectively transport and accumulate boron clusters into cells. These carriers consist of a lipopeptide, mercaptoundecahydrododecaborate (BSH), and a disulfide linker. The carriers were conceived according to the structure of pepducin, a membrane-penetrating lipopeptide targeting protease-activated receptor 1 (PAR1). To improve the membrane permeability of BSH, the structure was optimized using various lipopeptides possessing different peptides and lipid moieties. These synthesized lipopeptides were conjugated with BSH and evaluated for intracellular uptake using T98G glioblastoma cells. Among them, the most effectively incorporated and accumulated in the cells was compound 5 a, which contains a peptide of 13 residues derived from the intracellular third loop of PAR1 and a palmitoyl group. For further improvement of 10 B accumulation in cells, the introduction of an amine linker was investigated; intracellular uptake similar to that of 5 a was observed for compound 14, which has a piperazine linker. Both compounds 5 a and 14 showed a stronger radiosensitizing effect than BSH along on T98G cells under mixed-neutron beam irradiation. The results demonstrate that lipopeptide conjugation is effective for enhancing intracellular delivery and accumulation of BSH and improving the cytotoxic effect of BNCT.

PURPOSE To examine the effect of a change in reactor power on the response of solid tumors, referring to impact on quiescent (Q) tumor cell population. MATERIALS AND METHODS Tumor-bearing mice received 5-bromo-2'-deoxyuridine (BrdU) to label all proliferating (P) tumor cells, and were treated with boronophenylalanine-10B (BPA) or sodium mercaptododecaborate-10B (BSH). After reactor neutron beam irradiation at a power of 1 or 5 MW with an identical beam spectrum, cells from tumors were isolated and incubated with a cytokinesis blocker. The responses of BrdU-unlabeled Q and total (P + Q) tumor cells were assessed based on the frequencies of micronucleation using immunofluorescence staining for BrdU. RESULTS After neutron irradiation with or without 10B-carrier, radio-sensitivity was reduced by decreasing reactor power in both cells, especially in Q cells and after irradiation with BPA. The values of relative and compound biological effectiveness were larger at a power of 5 MW and in Q cells than at a power of 1 MW and in total cells, respectively. The sensitivity difference between total and Q cells was widened when combined with 10B-carrier, especially with BPA, and through decreasing reactor power. CONCLUSION 5 MW is more advantageous than 1 MW for boron neutron capture therapy.

Background: The aim of the study was to examine the dependency of p53 status and the usefulness of mild hyperthermia (MHT) as an inhibitor of recovery from radiation-induced damage, referring to the response of quiescent (Q) tumor cell population. Methods: Human head and neck squamous cell carcinoma cells transfected with mutant TP53 (SAS/ mp53 ) or with neo vector (SAS/ neo ) were injected subcutaneously into left hind legs of nude mice. Tumor-bearing mice received 5-bromo-2'-deoxyuridine (BrdU) continuously to label all intratumor proliferating (P) cells. They received high dose-rate I³-ray irradiation (HDR) immediately followed by localized MHT (40 °C for 2 h), or caffeine or wortmannin administration, or low dose-rate gamma-ray irradiation simultaneously with localized MHT or caffeine or wortmannin administration. Nine hours after the start of irradiation, the tumor cells were isolated and incubated with a cytokinesis blocker, and the micronucleus (MN) frequency in cells without BrdU labeling (= Q cells) was determined using immunofluorescence staining for BrdU. Results: SAS/ neo tumor cells, especially intratumor Q cell populations, showed a marked reduction in sensitivity due to the recovery from radiation-induced damage, compared with the total or Q tumor cells within SAS/ mp53 tumors that showed little recovery capacity. The recovery from radiation-induced damage was thought to be a p53- dependent event. In both total and Q tumor cells within SAS/ neo tumors, especially the latter, MHT efficiently suppressed the reduction in sensitivity caused by leaving an interval between HDR irradiation and the assay and decreasing the irradiation dose-rate, as well as the combination with wortmannin administration. Conclusions: From the viewpoint of solid tumor control as a whole, including intratumor Q-cell control, non-toxic MHT is useful for suppressing the recovery from radiation-induced damage, as well as wortmannin treatment combined with I³-ray irradiation. World J Oncol. 2019;10(3):132-141 doi: https://doi.org/10.14740/wjon1203

In cancer therapeutics, boron neutron capture therapy (BNCT) requires a platform for selective and efficient 10B delivery into tumor tissues for a successful treatment. However, the use of carborane, a promising candidate with high boron content and biostability, has significant limitations in the biomedical field due to its poor water-solubility and tumor-selectivity. To overcome these hurdles, we present in this study a fluorescent nano complex, combining fluorescent carborane and sodium hyaluronate for high boron concentration and tumor-selectivity. Tumor cells actively internalized the complex through binding hyaluronan to CD44, overexpressed on the tumor cell surface. Furthermore, the subcellular distribution of this complex could also be detected due to its fluorescent properties. Moreover, after thermal neutron irradiations, the complex produced excellent cytotoxicity, equal to or greater than that of the clinically-used BPA-fructose. Therefore, this novel complex could be potentially more suitable for BNCT than the boron agent.

Introduction: Hyperlipidemia is a well-established risk factor for cardiovascular disease. However, low cholesterol is also reported to be associated with poor outcome in chronic disease, which is called “cholesterol paradox”, and the impact of cholesterol level on the incidence of stroke or systemic embolism (SE) in atrial fibrillation (AF) remains unclear. Methods: The Fushimi AF Registry is a community-based prospective survey of the AF patients in Fushimi-ku, Kyoto, Japan. We obtained baseline total cholesterol level (TC) in 3,051 patients, and examined the relationship between TC and incidence of stroke/SE. Results: TC was inversely correlated with age and positively correlated with body weight. Patients with lower TC were more likely to be male, and had more diabetes, coronary artery disease, heart failure, prior stroke/SE, chronic kidney disease, and anemia. CHA 2 DS 2 -VASc score was inversely correlated with TC. Prescription of statin was higher in patients with lower TC, but that of oral anti-coagulants was not associated with TC. During the median follow-up of 1,476 days, stroke/SE occurred in 277 (9.1%) patients. After adjustment for the components of CHA 2 DS 2 -VASc score, body weight, and prescription of oral anti-coagulants and statins, TC had significant inverse association with the incidence of stroke/SE (hazard ratio (HR), 0.94; 95% confidence interval (CI) 0.91-0.98 for 10-mg/dl increase) (Table). TC was significantly associated with ischemic stroke/SE (HR, 0.95; 95% CI 0.91-0.99 for 10-mg/dl increase), but was not associated with intracranial bleeding (HR, 0.95; 95% CI 0.88-1.02 for 10-mg/dl increase). When we divided the patients into the elderly (≥75 years) and the young, low TC was a predictor for stroke/SE in the elderly (HR, 0.94; 95% CI 0.90-0.99 for 10-mg/dl increase), but was not in the young (HR, 0.95; 95% CI 0.90-1.01 for 10-mg/dl increase). Conclusions: Low TC might be an independent predictor for stroke/SE in elderly patients with AF.

Boron neutron capture therapy (BNCT) is a form of tumor-cell selective particle irradiation using low-energy neutron irradiation of boron-10 (10B) to produce high-linear energy transfer (LET) alpha particles and recoiling 7Li nuclei (10B [n, alpha] 7Li) in tumor cells. Therefore, it is important to achieve the selective delivery of large amounts of 10B to tumor cells, with only small amounts of 10B to normal tissues. To develop practical materials utilizing 10B carriers, we designed and synthesized novel dodecaboranethiol (BSH)-containing kojic acid (KA-BSH). In the present study, we evaluated the effects of this novel 10B carrier on cytotoxicity, 10B concentrations in F98 rat glioma cells, and micro-distribution of KA-BSH in vitro. Furthermore, biodistribution studies were performed in a rat brain tumor model. The tumor boron concentrations showed the highest concentrations at 1 h after the termination of administration. Based on these results, neutron irradiation was evaluated at the Kyoto University Research Reactor Institute (KURRI) with KA-BSH. Median survival times (MSTs) of untreated and irradiated control rats were 29.5 and 30.5 days, respectively, while animals that received KA-BSH, followed by neutron irradiation, had an MST of 36.0 days (p = 0.0027, 0.0053). Based on these findings, further studies are warranted in using KA-BSH as a new B compound for malignant glioma.

The use of anionic polyacrylamide (PAM) as a soil conditioner could help prevent soil loss by water. In this study, we determined the effective granular PAM rate that best reduces runoff and soil loss from Oxisols. Furthermore, the effectiveness of the selected PAM rate was tested by applying it in a mixture with gypsum (G) or lime (L). The study was conducted in two phases: (i) Dry PAM rates of 0 (C), 20 kg ha&minus, 1 (P20), 40 kg ha&minus, 1 (P40), and 60 kg ha&minus, 1 (P60) were applied onto soil surface and run for six consecutive rainfall storms of 70 mm h&ndash, 1 intensity for 1 h duration, and the effective PAM rate was selected, and (ii) G (4 t ha&ndash, 1) or L (2 t ha&ndash, 1) were applied alone or mixed with the selected PAM rate. The P20 was found to be effective in reducing runoff in the beginning while P40 and P60 were more effective starting from the third storm through the end of the consecutive storms, but with no statistically significant difference between P40 and P60. Hence, P40 was selected as the most suitable rate for the given test soil and rainfall pattern. On the other hand, the mixed application of P40 with G or L increased infiltration rate (IR) in the first two storms through improving soil solution viscosity. However, effectiveness of the mixtures had diminished by various degrees as rain progressed, as compared to P40 alone, which could be attributed to the rate and properties of G and L. In conclusion, the variation in effectiveness of PAM rates in reducing runoff with storm duration could indicate that the effective rates shall be selected based on the climatic region in that lower rates for the short rains or higher rates for elongated rains. Moreover, combined application of PAM with L could offer a good option to both fairly reduce soil erosion and improve land productivity especially in acidic soils like Oxisols, which requires further field verification.

Coffee plants are seasonally exposed to low chilling temperatures in many coffee-producing regions. In this study, we investigated the ameliorative effects of kinetin&mdash, a cytokinin elicitor compound on the nonenzymatic antioxidants and the photosynthetic physiology of young coffee plants subjected to cold stress conditions. Although net CO2 assimilation rates were not significantly affected amongst the treatments, the subjection of coffee plants to cold stress conditions caused low gas exchanges and photosynthetic efficiency, which was accompanied by membrane disintegration and the breakdown of chlorophyll pigments. Kinetin treatment, on the other hand, maintained a higher intercellular-to-ambient CO2 concentration ratio with concomitant improvement in stomatal conductance and mesophyll efficiency. Moreover, the leaves of kinetin-treated plants maintained slightly higher photochemical quenching (qP) and open photosystem II centers (qL), which was accompanied by higher electron transfer rates (ETRs) compared to their non-treated counterparts under cold stress conditions. The exogenous foliar application of kinetin also stimulated the metabolism of caffeine, trigonelline, 5-caffeoylquinic acid, mangiferin, anthocyanins and total phenolic content. The contents of these nonenzymatic antioxidants were highest under cold stress conditions in kinetin-treated plants than during optimal conditions. Our results further indicated that the exogenous application of kinetin increased the total radical scavenging capacity of coffee plants. Therefore, the exogenous application of kinetin has the potential to reinforce antioxidant capacity, as well as modulate the decline in photosynthetic productivity resulting in improved tolerance under cold stress conditions.

The current study investigates the phytochemical composition of coffee plant organs and their corresponding antioxidant capacities compared to green and roasted coffee beans. HPLC analysis indicated that the investigated compounds were present in all organs except mangiferin, which was absent in roots, stems and seeds, and caffeine, which was absent in stems and roots. Total phytochemicals were highest in the green beans (GB) at 9.70 mg g&minus, 1 dry weight (DW), while roasting caused a 66% decline in the roasted beans (RB). This decline resulted more from 5&ndash, CQA and sucrose decomposition by 68% and 97%, respectively, while caffeine and trigonelline were not significantly thermally affected. Roasting increased the total phenolic content (TPC) by 20.8% which was associated with an increase of 68.8%, 47.5% and 13.4% in the antioxidant capacity (TEAC) determined by 2,2&ndash, diphenyl&ndash, 1&ndash, picryl hydrazyl radical (DPPH), 2,2&ndash, azino bis (3&ndash, ethyl benzothiazoline&ndash, 6&ndash, sulphonic acid) radical (ABTS) and Ferric ion reducing antioxidant power (FRAP) assays, respectively. Amongst the leaves, the youngest (L1) contained the highest content at 8.23 mg g&minus, 1 DW, which gradually reduced with leaf age to 5.57 mg g&minus, 1 DW in the oldest (L6). Leaves also contained the highest TPC (over 60 mg g&minus, 1 GAE) and exhibited high TEAC, the latter being highest in L1 at 328.0, 345.7 and 1097.4, and least in L6 at 304.6, 294.5 and 755.1 &micro, mol Trolox g&minus, 1 sample for the respective assays. Phytochemical accumulation, TPC and TEAC were least in woody stem (WS) at 1.42 mg g&minus, 1 DW, 8.7 mg g&minus, 1 GAE, 21.9, 24.9 and 110.0 &micro, 1 sample, while herbaceous stem (HS) contained up to 4.37 mg g&minus, 27.8 mg g&minus, 110.9, 124.8 and 469.7 &micro, 1 sample, respectively. Roots contained up to 1.85 mg g&minus, 1 DW, 15.8 mg&minus, 1 GAE and TEAC of 36.8, 41.5 and 156.7 &micro, 1 sample. Amongst the organs, therefore, coffee leaves possessed higher values than roasted beans on the basis of phytochemicals, TPC and TEAC. Leaves also contain carotenoids and chlorophylls pigments with potent health benefits. With appropriate processing methods, a beverage prepared from leaves (coffee leaf tea) could be a rich source of phytochemicals and antioxidants with therapeutic and pharmacological values for human health.

A polypeptide with a GlyHisGly repeating sequence containing zwitterionic structures that effectively interact with cellulose was synthesized for dissociation of cellulose crystals. Polypeptide with the GlyHisGly sequence was synthesized by chemoenzymatic polymerization and postfunctionalization of the His residues was performed to afford imidazolium butyrate on the side chains. The resulting zwitterionic polypeptide effectively dissociated bundles of tunicate cellulose nanocrystals, even when the conditions were mild and the concentration of the polypeptide was as low as 1-2 mg mL-1. Polypeptide treatment also affected the morphology of the cell walls in cultured plant cells, and the cellulose microfibril networks and amorphous polysaccharide layer were dissociated according to atomic force microscopy (AFM). The zwitterionic polypeptide treatment did not change the crystal structure of the cellulose nanocrystals. Analysis of the mechanical properties of the cellulose nanocrystals by force curve measurements using AFM revealed that the elastic modulus of the cellulose nanocrystals increased after treatment with the zwitterionic polypeptide, indicating that the amorphous part of the cellulose nanocrystals was removed by interactions with the polypeptide. At a concentration of the polypeptide that enabled the dissociation of the cellulose network, the zwitterionic polypeptide showed negligible cytotoxicity to the plant cells. The mild and noncytotoxic technique for loosening cellulose microfibrils/nanocrystals that was developed in this study has tremendous significance for the modification of cellulose in terms of polymer chemistry, material science, and plant biotechnology.

Proteins are covalently trapped on DNA to form DNA-protein cross-links (DPCs) when cells are exposed to DNA-damaging agents. Aldehyde compounds produce common types of DPCs that contain proteins in an undisrupted DNA strand. Tyrosyl-DNA phosphodiesterase 1 (TDP1) repairs topoisomerase 1 (TOPO1) that is trapped at the 3'-end of DNA. In the present study, we examined the contribution of TDP1 to the repair of formaldehyde-induced DPCs using a reverse genetic strategy with chicken DT40 cells. The results obtained showed that cells deficient in TDP1 were sensitive to formaldehyde. The removal of formaldehyde-induced DPCs was slower in tdp1-deficient cells than in wild type cells. We also found that formaldehyde did not produce trapped TOPO1, indicating that trapped TOPO1 was not a primary cytotoxic DNA lesion that was generated by formaldehyde and repaired by TDP1. The formaldehyde treatment resulted in the accumulation of chromosomal breakages that were more prominent in tdp1-deficient cells than in wild type cells. Therefore, TDP1 plays a critical role in the repair of formaldehyde-induced DPCs that are distinct from trapped TOPO1.

The role of strain rate ( $${{\dot \varepsilon }}$$ ) in the strain-induced crystallization (SIC) of vulcanized natural rubber (NR) and synthetic isoprene rubber (IR) was studied using in situ wide-angle X-ray scattering (WAXS) (synchrotron X-ray radiation). We developed homemade extension equipment and coupled it with the synchronized time-resolved X-ray detector system. The nucleation rate (I) was determined for a wide range of $${{\dot \varepsilon }}$$ values (0.0075 s−1–330 s−1) based on the increase in the scattering intensity (IX) as a function of time (t). We found that I is proportional to $${\dot{\varepsilon }}$$ ( $$I \propto \dot \varepsilon$$ ). Based on this result, we concluded that $$\dot \varepsilon$$ plays an important role in the kinetic mechanism of the SIC of NR and IR. The role of strain rate ( $$\dot \varepsilon$$ ) in strain induced crystallization (SIC) of vulcanized natural rubber (NR) and synthetic isoprene rubber (IR) was studied by in-situ wide angle X-ray scattering (WAXS). The nucleation rate (I) was determined by measuring the slope on the plot of the scattering intensity (IX) as a function of time (t). Various I values were determined for various $$\dot \varepsilon$$ . On the plot of I vs. $$\dot \varepsilon$$ , we found that I is proportional to $$\dot \varepsilon$$ ; I ∝ $$\dot \varepsilon$$ .

Plants absorb silicon (Si) from soil solution in the form of monosilicic acid, also called orthosilicic acid (H4SiO4). Application of organic and inorganic materials containing readily soluble Si can increase Si supply in the soil and its uptake by plant. The study aimed to evaluate the release of Si from organic and inorganic material sources and its uptake by rice plant. The released phosphorus (P) from those materials was also evaluated. The inorganic materials evaluated included fly ash, steel slag, silica gel and Japanese silica gel (JSG), while the organic materials consisted of rice husk ash (RHA), rice husk burnt (RHB), media of mushroom (MM), cacao shell biochar (cacao SB) and rice straw compost (RSC). The dynamics of Si and P were observed by periodical samplings at 7, 17, 24 and 34 days after transplanting (DAT). Tiller number and plant height were measured at 16, 21 and 36 DAT. The results showed that Si concentration in solution derived from inorganic material was highest for JSG followed by silica gel (1.107 and 0.806 mmol L-1, respectively). The release of Si from organic material was higher for RHB and RHA (0.618 and 0.539 mmol L-1, respectively). Cacao SB, silica gel, JSG and RHB significantly increased plant height at 36 DAT. Meanwhile, Si materials did not significantly affect the tiller number. Of the materials used, steel slag and JSG significantly affected Si uptake by rice plant.

The present study for the first time reports the occurrence, distribution, ecological and resistance risks of antibiotics in the surface water of freshwater finfish and brackish water shellfish aquaculture in Bangladesh. Among the nine targets, seven antibiotics were detected in finfish aquaculture, whereas four in shellfish aquaculture. The concentrations (ranges) and overall detection frequency of sulfamethoxazole (SMX) (nd-20.02 ng L−1 and 73%), trimethoprim (TMP) (nd-41.67 ng L−1 and 60%), tylosin (TYL) (nd-39.34 ng L−1 and 60%), sulfadiazine (SDZ) (nd-17.97 ng L−1 and 53%), sulfamethazine (SMT) (nd-11.71 ng L−1 and 33%), sulfamethizole (SMZ) (nd-10.81 ng L−1 and 40%) and penicillin G (PC_G) (nd-7.83 ng L−1, 7%) were found in finfish aquaculture. In case of shellfish aquaculture, the concentrations (ranges) and overall detection frequency were for SMX (nd-16.77 ng L−1 and 67%), TMP (nd-11.39 ng L−1 and 20%), TYL (nd-0.16 ng L−1 and 20%) and erythromycin-H2O (ERY-H2O) (nd-3.91 ng L−1 and 20%). The present findings revealed that finfish aquaculture is more contaminated with the higher numbers and concentrations of antibiotics. The preliminary ecological and resistance risks assessment showed that the calculated risk quotients (RQs) were lower than one (RQs

This study reports the first evidence of the occurrence of PFAAs in commonly consumed seafood from the coastal area of Bangladesh. Fifteen target PFAAs in 48 seafood samples (5 finfish and 2 shellfish species) were measured by HPLC-MS/MS. The ΣPFAAs in finfish and shellfish were in the range of 0.32-14.58 and 1.31-8.34 (ng/g wet weight), respectively. Perfluorooctanesulfonate (PFOS) in finfish (0.1-3.86ng/g ww), whereas perfluorooctanoic acid (PFOA) in shellfish (0.07-2.39ng/g ww) were the most abundant PFAAs. The results were comparable with other studies worldwide, particularly from China, Spain, Sweden, and USA. The majority of monitored PFAAs did not show clear seasonal variation. However, seafood from the southeast area (Cox's Bazar and Chittagong) showed relatively higher levels of PFAAs. Moreover, the dietary exposure assessment revealed that the daily intakes of PFAAs via seafood consumption were far less than the health-based guidelines, indicating low health risk for the Bangladeshi coastal residents.

We aimed to develop a highly sensitive method to detect ESR1 mutations in cell-free DNA (cfDNA) using next-generation sequencing with molecular barcode (MB–NGS) targeting the hotspot segment (c.1600–1713). The sensitivity of MB–NGS was tested using serially diluted ESR1 mutant DNA and then cfDNA samples from 34 patients with metastatic breast cancer were analyzed with MB–NGS. The results of MB–NGS were validated in comparison with conventional NGS and droplet digital PCR (ddPCR). MB–NGS showed a higher sensitivity (0.1%) than NGS without barcode (1%) by reducing background errors. Of the cfDNA samples from 34 patients with metastatic breast cancer, NGS without barcode revealed seven mutations in six patients (17.6%) and MB–NGS revealed six additional mutations including three mutations not reported in the COSMIC database of breast cancer, resulting in total 13 ESR1 mutations in ten patients (29.4%). Regarding the three hotspot mutations, all the patients with mutations detected by MB–NGS had identical mutations detected by droplet digital PCR (ddPCR), and mutant allele frequency correlated very well between both (r = 0.850, p

Magnetic separation can be considered a green technology because it is fast, efficient, consumes low energy, and minimizes the use of solvents and the generation of waste. It has been successfully used in laboratory scale to facilitate supported catalysts’ handling, separation, recovery, and recycling. Only few materials are intrisically magnetic, hence the application of magnetic materials as catalyst supports has broaden the use of magnetic separation. Iron oxides, silica-coated iron oxides, and carbon-coated-cobalt are among the most studied catalyst supports; however, other metal oxide coatings, such as ceria and titania, are also very interesting for application in catalysis. Here we report the preparation of magnetically recoverable magnetic supports containing silica, ceria, and titania. We found that the silica shell protects the iron oxide core and allows the crystalization of ceria and titania at high temperature without compromising the magnetic properties of the catalyst supports.

Molecular aggregation structure and mechanical as well as thermal properties of novel well-defined multiblock copolymers consisting of crystalline syndiotactic polystyrene (sPS) and rubbery hydrogenated polyisoprene (hPIp) were investigated. The morphology and crystalline ordered structure of the multiblock copolymer films prepared by solvent casting from 1,2-dichlorobenzene solution depended on the volume fraction of sPS (VFsPS) and number of blocks. The multiblock copolymer films exhibited ordered morphology with low crystallinity. The crystallinity of the sPS reduced with decreasing the VFsPS. The pentablock copolymer produced more ordered morphology and less crystallinity than the triblock copolymers. The anisotropic orientation and mechanical stability of the δ form sPS crystals in the spherical sPS domains during uniaxial stretching were demonstrated. Tensile testing and dynamic mechanical analysis indicated that these multiblock copolymer films with appropriate sPS fraction are strong, tough, and e...

A liquid/liquid interfacial synthesis is employed, for the first time, to synthesize a covalent two-dimensional polymer nanosheet. Copper-catalyzed azide–alkyne cycloaddition (CuAAC) between a three-way terminal alkyne and azide at a water/dichloromethane interface generates a 1,2,3-triazole-linked nanosheet. The resultant nanosheet, with a flat and smooth texture, has a maximum domain size of 20 μm and minimum thickness of 5.3 nm. The starting monomers in the organic phase and the copper catalyst in the aqueous phase can only meet at the liquid/liquid interface as a two-dimensional reaction space; this allows them to form the two-dimensional polymer. The robust triazole linkage generated by irreversible covalent-bond formation allows the nanosheet to resist hydrolysis under both acidic and alkaline conditions, and to endure pyrolysis up to more than 300 °C. The coordination ability of the triazolyl group enables the nanosheet to act as a reservoir for metal ions, with an affinity order of Pd2+>Au3+>Cu2+.

The effects of spinning conditions on fiber properties are not well explained by the fiber structures because the birefringence, crystallinity, and SAXS patterns are often similar. In this study, the effects on the fiber structure development of polyethylene terephthalate after necking was analyzed by simultaneous WAXD/SAXS measurements. An X-shaped SAXS pattern was observed for all fibers drawn at the minimum draw ratio. In contrast, by drawing under a drawing stress of 100 MPa, the strong diffraction of the smectic phase and an obviously larger long period less than 1 ms after necking were observed for fibers spun at 500-1500 m/min, while almost no smectic phase was observed for fibers spun at 2000 m/min. A higher crystallization rate and clear draw ratio dependence of crystallization rate were also observed for the fiber spun at 2000 m/min. The clear differences in structure development can explain their differences in tensile strength and thermal shrinkage. (C) 2017 Elsevier Ltd. All rights reserved., Article, POLYMER.116:367-377(2017)

Fiber properties are decided by its structure, and the structure are mainly formed in the fiber drawing process. In this study, the effects of the draw ratio on the fiber structure development of polyethylene terephthalate after continuous neck-drawing were investigated using simultaneous WAXD/SAXS measurements. Low-oriented amorphous as-spun fibers were drawn to a draw ratio of 3.0-4.5, at which the fiber can be stably neck drawn. WAXD and SAXS images were obtained up to 2.0 ms when the structure was mainly developed. The smectic (0010) diffraction intensity and long period increased with increasing draw ratio up to 4.2, and a larger (0010) diffraction d-spacing was observed at a draw ratio of 4.5. The results suggest that more fibrillar structures were formed with increasing draw ratio up to 4.2, and more constrained molecular bundles were formed at a draw ratio of 4.5. A larger amount of constrained fibrillar structures can bear a greater tensile force in tensile tests, therefore the drawn fibers have higher tensile strengths. (C) 2017 Elsevier Ltd. All rights reserved., Article, POLYMER.116:357-366(2017)

The effect of molecular mobility of a pre-crystallized phase on the isothermal crystallization in the microphase-separated lamellar morphology of a strongly segregated crystalline-crystalline block copolymer, poly(ethylene glycol)- block -poly(perfluorooctylethyl acrylate) (PEG- b -PFA-C 8 ), was investigated. The diblock copolymer produced a microphase-separated lamellar morphology in the melt state, and the precedent crystallization of PFA-C 8 blocks provided the lamellar confinement field. The counter PEG block crystallized within the lamellar confinement field. The molecular mobility of the pre-crystallized PFA-C 8 phase was modulated by the thermal history. The structural evolution was monitored by a complementary combination of in situ time-resolved simultaneous small-angle X-ray scattering/wide-angle X-ray diffraction measurements and thermal analyses. The degree of crystallinity and the melting temperature of the PEG crystals were associated with the molecular mobility of the pre-crystallized PFA-C 8 phase. The highly packed PFA-C 8 phase (higher-ordered phase) constrained the PEG crystallization, whereas the loosely packed PFA-C 8 phase (lower-ordered phase) caused a weak restriction in the PEG crystallization to give relatively ordered PEG crystals. Subsequent crystallization in a confinement field of crystalline-crystalline block copolymers was controlled by adjusting the molecular mobility of the pre-crystallized phase.

Perfluoroalkyl acids (PFAAs) are persistent environmental pollutants that have been detected in various media including human serum. Due to concerns regarding their bioaccumulation and possible negative health effects, an understanding of routes of human exposure is necessary. PFAAs are recalcitrant in many water treatment processes, making drinking water a potential source of human exposure. This study presents the first report on contamination from PFAAs in river and drinking water in Ghana. The targeted PFAAs were perfluoroalkyl carboxylic acids (PFCAs) with C4–14 carbon chain and perfluoroalkane sulphonic acids (PFSAs) with C6, 8, 10. Five PFAA congeners – PFOA, PFOS, PFHxA, PFDA and PFPeA – were commonly detected in river and tap water. The mean concentrations of ∑ PFAAs in the Kakum and Pra Rivers were 281 and 398 ng/L, while tap water (supplied from the treatment of water from those rivers) contained concentrations of 197 and 200 ng/L, respectively. PFOA and PFOS constituted about 99% of the ∑ PFAAs. The risk quotient (RQ) attributed to drinking of tap water was estimated at 1.01 and 1.74 for PFOA and PFOS, respectively. For a country that has not produced these compounds, the RQs were unexpectedly high, raising concerns particularly about contamination from such emerging pollutants in local water sources. The study revealed limitations of local tap water treatment in getting rid of these emerging pollutants.

Background: The aim of the study was to examine the effect of tirapazamine (TPZ) on recovery from radiation-induced damage in pimonidazole-unlabeled quiescent (Q) tumor cells compared with that of metformin (Met) or mild temperature hyperthermia (MTH). Methods: Proliferating (P) cells in EL4 tumors were labeled by continuous 5-bromo-2'-deoxyuridine (BrdU) administration. Tumors received gamma-rays at 1 h after pimonidazole administration followed by Met or TPZ treatment or MTH. Twenty-four hours later, the responses of Q and total (P + Q) cells and those of the pimonidazole-unlabeled cells were assessed with micronucleation and apoptosis frequencies using immunofluorescence staining for BrdU and apoptosis frequency using immunofluorescence staining for pimonidazole, respectively. Results: With gamma-rays only, the pimonidazole-unlabeled cell fraction showed significantly enhanced radio-sensitivity compared with the whole cell fraction more remarkably in Q than total cells. However, a significantly greater decrease in radio-sensitivity in the pimonidazole-unlabeled than the whole cell fraction, evaluated using a delayed assay, was more clearly observed in Q than total cells. Post-irradiation MTH or Met treatment more clearly repressed the decrease in radio-sensitivity in the Q than total cells. Post-irradiation TPZ administration produced a large radio-sensitizing effect on both total and Q cells, especially on Q cells. In pimonidazole-unlabeled cell fractions in both total and Q cells, TPZ suppressed the reduction in sensitivity much more efficiently than MTH or Met without any radio-sensitizing effect. Conclusion: Post-irradiation TPZ administration has the potential to both suppress recovery from radiation-induced damage and enhance the radio-sensitivity both in total and Q tumor cells. Post-irradiation TPZ administration may be useful for controlling tumors. World J Oncol. 2017;8(5):137-146 doi: https://doi.org/10.14740/wjon1058w Â

Peptides exhibit no melting behavior during heating due to their strong intermolecular hydrogen bonds, which limits the use of peptides as a bulk material. Here, we added a melting point to peptides by introducing nylon monomer units via papain-catalyzed chemoenzymatic synthesis. The peptides containing 14 mol% nylon units had a melting point of approximately 200 °C.

N-Unsubstituted thienoisoindigo (TIIG) and its diphenyl derivative (dph-TIIG) are synthesized by using a tert-butoxy carbonyl (t-Boc) group as a protecting group. TIIG has a stacking structure analogous to isoindigo, and dph-TIIG is a hybrid of brickwork and herringbone structures. These compounds exhibit ambipolar transistor properties and particularly dph-TIIG shows the maximum hole and electron mobilities greater than 0.1 cm2 V−1 s−1.

This study identified seasonal water quality characteristics in two adjacent mountainous rivers (Sangharus and Sekampung Hulu Rivers) in Lampung, Indonesia and determined the impacts of fertilizer application on river chemistry as a result of social forestry management. In 2016, we measured water chemistry and conducted a farmers&rsquo, questionnaire survey to obtain information on fertilizer application. The water quality results indicated that several parameters, including nitrate (NO3) and phosphate (PO4), were significantly higher in the Sangharus River than in the Sekampung Hulu River. In addition, several parameters were influenced by dilution from high river flow in the rainy season. Some parameters were likely influenced by the weathering of parent materials. By contrast, electrical conductivity (EC) and NO3 were higher in the rainy season, which was likely linked to the dominant timing of urea fertilizer application during this season. Despite the application of fertilizers in the watersheds, NO3 levels remained below the recommended standard. However, aluminum and iron concentrations were higher than the recommended level for drinking water, which was likely due to elevated soil erosion from improper land management. Therefore, we recommend that effective land management policies be implemented through the adoption of soil conservation practices for nutrient loss prevention.

Structural change during cyclic stretching/shrinking of drawn film of linear low-density polyethylene (LLDPE) was analyzed using a combination of in-situ X-ray and NMR measurements. Small-angle X-ray scattering (SAXS) for the original drawn LLDPE film before stretching exhibits a split-layer-line pattern, indicating lamellar tilt. Stretching the film transforms the pattern into the straight-layer-line one, and subsequent shrinking regains the original split-layer-line one. Solid-state 1H-NMR measurements detected three components having different relaxation times for both originally shrunk and subsequently stretched states. Among these components, the intermediate one exhibits reversible change in relaxation time, synchronizing the stretching/shrinking cycles. This component is attributed to tie molecules, bridging the rigid components of crystalline lamellae and accompanying a small amount of the mobile component consisting of unrestricted amorphous chains. Stretching and shrinking such tie molecules induces reversible transformation of the microscopic lamellar arrangements, which causes macroscopic actuation of drawn LLDPE.

Perfluorosulfonated ionomers are the most successful ion-exchange membranes at an industrial scale. One recent, cutting-edge application of perfluorosulfonated ionomers is in polymer electrolyte fuel cells (PEFCs). In PEFCs, the ionomers are used as a component of the catalyst layer (CL) in addition to functioning as a proton-exchange membrane. In this study, the microstructures in the CLs of PEFCs were characterized by combined synchrotron X-ray scattering and transmission electron microscopy (TEM) analyses. The CL comprised a catalyst, a support, and an ionomer. Fractal dimensional analysis of the combined ultrasmall- and small-angle X-ray scattering profiles indicated that the carbon-black-supported Pt catalyst (Pt/CB) surface was covered with the ionomer in the CL. Anomalous X-ray scattering revealed that the Pt catalyst nanoparticles on the carbon surfaces were aggregated in the CLs. These findings are consistent with the ionomer/catalyst microstructures and ionomer coverage on the Pt/CB surface obtained from TEM observations.

In this work, we report the preparation of high-purity perfluorosulfonated ionomer (Nafion) nanofibers (NFs) via solution blow spinning (SBS). Fiber formation in solution jet spinning is strongly dependent on the structure of the spinning solution. Upon adding a small amount of poly(ethyleneoxide) (PEO) as a spinning aid to Nafion dispersion, most of the highly ordered Nafion aggregate disappeared, allowing the stable production of bead-free and smooth high-purity NFs (Nafion/PEO = 99/1) by SBS. The microstructure of the blowspun Nafion NFs differed from that of electrospun NFs. In the blowspun NFs, incomplete microphase separation between hydrophilic (ionic) and hydrophobic domains was observed, but the crystallization of CF2−CF2 chains was enhanced owing to the high extensional strain rate and rapid solidification during SBS. These findings provide fundamental information for the preparation and characterization of blowspun Nafion NFs.

Herein, we report a new device that generates a high-purity hydroxide solution in line. The device's container has three compartments that are isolated from each other by two cation exchange (CE) membranes. In each end of the container, an electrode is installed. The three compartments are filled with ion exchange resins. A bipolar boundary is a composite boundary comprising anion- and cation-exchangers. This device has two bipolar boundaries, which are used to separate the location of hydroxide solution generation from the location where water is electrolyzed. Therefore, it can produce high-purity hydroxide solutions that are free from gases and anionic impurities. The hydroxide solution is generated on the basis of an electrokinetic phenomenon at the surfaces of ion-exchange resins and membranes in an electric field; NaOH concentration can be controlled at rates from 0.01 to 100mM per 1mL/min by adjusting the electrical current (0-200mA) applied to the device. As the generated solution is used as an eluent for a suppressed anion chromatography, the electrical conductivity of the effluent from the suppressor is as low as that of ultra-pure water. Thus, the noise of the base-line electrical conductivity is improved, and so the detection limit of anions on the sub-ng/mL order can be achieved.