Synergistic Effects of Polybenzimidazole and Aramide on Enhancing Flame-Retardancy and Solubility

Aromatic and functional polymers with processibility derived from biobased starting materials are prerequisite considering sustainable society. Poly(2,5-benzimidazole)s are rigid-rod polymers to show ultrahigh thermal stability such as flame retardance, while usually suffer from poor solubility. Here, poly(benzimidazole-co-amide)s are synthesized from two biobased monomers, 3,4-diaminobenzoic acid and a semirigid comonomer, 4-aminohydrocinnamic acid. The copolymers with an amide composition of 80 mol% and higher are soluble in widely used polar solvents to fabricate the films keeping high flame retardance, which is comparable with popular high-performance polymers such as aromatic polyimides, polyetheretherketone, polyphenylene sulfide, etc.     

Defining Dry Eye from a Clinical Perspective

Over the past decades, the number of patients with dry eye disease (DED) has increased dramatically. The incidence of DED is higher in Asia than in Europe and North America, suggesting the involvement of cultural or racial factors in DED etiology. Although many definitions of DED have been used, discrepancies exist between the various definitions of dry eye disease (DED) used across the globe. This article presents a clinical consensus on the definition of DED, as formulated in four meetings with global DED experts. The proposed new definition is as follows: “Dry eye is a multifactorial disease characterized by a persistently unstable and/or deficient tear film (TF) causing discomfort and/or visual impairment, accompanied by variable degrees of ocular surface epitheliopathy, inflammation and neurosensory abnormalities.” The key criteria for the diagnosis of DED are unstable TF, inflammation, ocular discomfort and visual impairment. This definition also recommends the assessment of ocular surface epitheliopathy and neurosensory abnormalities in each patient with suspected DED. It is easily applicable in clinical practice and should help practitioners diagnose DED consistently. This consensus definition of DED should also help to guide research and clinical trials that, to date, have been hampered by the lack of an established surrogate endpoint.     

Streptococcal infection in the pathogenesis of Beh?et's disease and clinical effects of minocycline on the disease symptoms

Although the precise pathoetiology of Beh?et's disease (BD) remains obscure, patients with BD have a high incidence of chronic infectious foci, indicating an enhanced susceptibility to chronic tonsillitis, and dental caries. Sometimes, clinical symptoms appear after treatment of these foci in BD patients. It is believed that BD might be related to an allergic reaction to a bacterial infection in view of the many clinical symptoms, especially the presence of aphthous and genital ulcerations. An attempt to obtain cutaneous responses to bacterial antigens has been carried out using various vaccines developed from bacteria isolated from the ulcerative lesions and oral cavities of BD patients. BD patients often show intense hypersensitivity to various strains of streptococci, not only by their cutaneous reactions but also by in vitro testing. In this report, we describe our previous studies on the correlation between streptococcal antigens and the pathogenesis of BD and also discuss the recent reports of other authors. The intense hypersensitivity to streptococcal antigens acquired after streptococcal infection is thought to play an important role in the appearance of symptoms in BD patients since the production of pro-inflammatory cytokines by peripheral blood mononuclear cells (PBMC) was enhanced when stimulated with streptococcal antigen in a culture system. Minocycline, an antibiotic to which certain strains of streptococci are sensitive, reduced the frequency of clinical symptoms in BD patients as well as the production of pro-inflammatory cytokines by BD-PBMC stimulated with streptococcal antigen.     

Comparison of activities in selective catalytic reduction of NOx by C3H8 over Co/MFI, Fe/MFI, and H/MFI zeolite catalysts

The Co/MFI(SiO₂/Al₂O₃ = 30) were prepared by a precipitation method with NaOCl in alkali solutions exhibited high activities to N₂ at 250 °C for the selective catalytic reduction (SCR) of NO_x. These catalysts showed two UV–vis bands at 700 and 400 nm, indicating the presence of octahedral Co(III) as well as tetrahedral Co(II). The high SCR activity over such Co(III, II)/MFI(30) seems to come from Co(III)---O moieties. The Co(II)MFI(30) catalysts prepared from Co(II)Cl₂ exhibited low SCR activities due to the presence of tetrahedral Co(II) ions in MFI. Less CO formation occurred over Co/MFI catalysts. The Fe/MFI(30) catalyst exhibited high activity due to the presence of some Fe---O species in MFI but more amount of CO were produced during SCR. H/MFI(30) catalyst exhibited a good SCR activity. However, more amount of carbonaceous deposits were produced on it. The correlation between acid concentration and SCR activity was discussed over H/MFIs.     

Radiation detector made of a high-quality polycrystalline diamond

Radiation detector was made of a high-quality CVD polycrystalline diamond composed of frost column like structure diamond grains, and induced charge distribution spectra and drift velocities were measured by using alpha particles. As a result, the CVD polycrystalline achieved maximum induced charge of 83% of HP/HT type IIa diamond. Moreover, the CVD crystal had lower charge loss on electrons compared with the HP/HT type IIa diamond. Drift velocities of electrons and holes were v_e = 7.7 × 10⁴ and v_h = 7.3 × 10⁴cm/s at an electric field of 20 kV/cm, respectively. In addition, response function measurement for 14 MeV neutrons was carried out.     

A non-specific lipid transfer protein from Arabidopsis is a cell wall protein

Lipid transfer proteins (LTPs), mediate the transfer of phospholipids between membranes in vitro. However, the in vivo function of LTPs is not known. To determine the precise location of a non-specific LTP from Arabidopsis, a cDNA clone was used to produce an Arabidopsis LTP:protein A fusion. Antibodies raised against the fusion were used to localize the Arabidopsis LTP by immunoelectron microscopy. LTP was found to be located in the cell wall, mainly in epidermal cells. This location appears to be inconsistent with the proposed role of the protein in intracellular lipid transfer.     

Analysis of brushless three-phase synchronous generator without exciter

Recently, a demand for small-capacity generators has been increasing as electric sources in small ships and automobiles or as portable electric sources driven by engines. It is desired that the structure of small-capacity generators be simple and robust, and that the generators be highly reliable, easily maintained and controlled. This paper describes an analysis of the original brushless synchronous generator without exciter. The output voltage can be adjusted in the wide range by controlling the stator dc current. To analyze the characteristics of this generator, the finite element method is applied. It is found that the results of theoretical analysis agree well with the experimental results.     

Metabolism of tetramethrin isomers in rat: II. Identification and quantitation of metabolites

1. To examine the metabolic fate of (1RS, trans)- or (1RS, cis)-tetramethrin [3, 4, 5, 6-tetrahydrophthalimidomethyl (1RS, trans)- or (1RS, cis)-chrysanthemate], rat was administered a single oral dose of trans- or cis-[alcohol-14C]tetramethrin at dose levels of 2 or 250 mg/kg. 2. The radiocarbon was almost completely eliminated from rat within 7 days after administration in all groups. 14C-recoveries (expressed as percentages relative to the dosed 14C) in faeces and urine were 38-58 and 42-58% respectively in rat administrated trans-[alcohol-14C]tetramethrin, and in faeces and urine were 66-91 and 9-31% respectively in rat administered cis-[alcohol-14C]tetramethrin. 3. Fourteen metabolites found in excreta were purified by using several chromatographic techniques and identified by spectroanalyses (nmr and MS). Five sulphonate derivatives and three dicarboxylic acid derivatives were found. 4. The main metabolites were sulphonate derivatives in the faeces, and in the urine, alcohols, dicarboxylic acid and reduced metabolites derived from the 3,4,5,6-tetrahydrophthalimide moiety.