Thermally stable multi-mode polymer optical waveguide fabricated by single-step photo-patterning of fluorinated polyimide/epoxy hybrids

ABSTRACT Novel polyimide (PI)/epoxy hybrid material for single-step photo-patterning of optical waveguides was prepared by blending of a semi-aromatic fluorinated poly(amic acid silylester) (PASE), a cycloaliphatic epoxy compound, and a photo-acid generator. A large refractive index change (δn, > 0.01), which is sufficient for multi-mode optical waveguides, was obtained between the polymer films prepared with and without UV irradiation. The refractive index change was generated by cationic reaction between the silylated carbonyl ester groups of PASE and epoxy rings, which was initiated by UV irradiation and promoted by successive thermal curing. The difference in molecular structures, which results in the refractive index changes, were characterized by FT-IR measurements, and it was clarified that the films with and without UV irradiation showed PASE and PI structures, respectively. These films exhibited high thermal stability higher than 230°C, which are desirable for waveguide fabrication for optical inter-connects and lightwave circuits. Using this hybrid material, channel-type optical waveguides were successfully fabricated by the single-step photo-patterning procedure without development by aqueous or organic solvents, which is more facile and economical for waveguide mass-fabrication

Insulin-like growth factor 1 predicts decompensation and long-term prognosis in patients with compensated cirrhosis

AimInsulin-like growth factor 1 (IGF-1), which is primarily produced in hepatocytes and is associated with liver functional reserve, plays a crucial role in the pathological condition of cirrhosis. This study aimed to investigate the usefulness of serum IGF-1 levels for predicting the long-term prognosis and decompensation development in patients with cirrhosis.MethodsWe retrospectively evaluated 148 patients with cirrhosis and divided them into three groups according to baseline IGF-1 levels: low (L)-, intermediate (I)-, and high (H)-IGF-1 groups. The cumulative survival rates were compared among these groups in compensated and decompensated cirrhosis, respectively. Significant and independent factors associated with mortality and decompensation development were identified using Cox proportional hazards regression analysis.ResultsThe median observation period was 57.1 (41.7–63.2) months. Thirty (20.3%) patients died of liver disease-related events and 21 (22.3%) patients with compensated cirrhosis developed decompensation. Multivariate analysis identified low serum IGF-1 levels as a significant and independent factor associated with mortality (all patients: hazard ratio [HR], 0.967; p = 0.004; patients with compensated cirrhosis: HR, 0.927; p = 0.002). The cumulative survival rates were significantly lower in the L-IGF-1 group than in the H-IGF-1 and I-IGF-1 groups (all patients: p < 0.001 and = 0.009; patients with compensated cirrhosis: p = 0.012 and 0.003, respectively). However, in decompensated cirrhosis, the cumulative survival rates demonstrated no significant differences among the three groups. The cumulative decompensation incidence rates were significantly higher in the L-IGF-1 group than in the H-IGF-1 and I-IGF-1 groups (p < 0.001 and = 0.009, respectively). Low serum IGF-1 levels were significantly and independently associated with decompensation development (HR, 0.939; p < 0.001).ConclusionLow serum IGF-1 levels were significantly and independently associated with decompensation development and poor long-term prognosis in patients with compensated cirrhosis. Therefore, IGF-1 may be useful for predicting decompensation-related events and should be regularly monitored in the management of compensated phase

Thermally stable multi-mode polymer optical waveguide fabricated by single-step photo-patterning of fluorinated polyimide/epoxy hybrids

ABSTRACT Novel polyimide (PI)/epoxy hybrid material for single-step photo-patterning of optical waveguides was prepared by blending of a semi-aromatic fluorinated poly(amic acid silylester) (PASE), a cycloaliphatic epoxy compound, and a photo-acid generator. A large refractive index change (δn, > 0.01), which is sufficient for multi-mode optical waveguides, was obtained between the polymer films prepared with and without UV irradiation. The refractive index change was generated by cationic reaction between the silylated carbonyl ester groups of PASE and epoxy rings, which was initiated by UV irradiation and promoted by successive thermal curing. The difference in molecular structures, which results in the refractive index changes, were characterized by FT-IR measurements, and it was clarified that the films with and without UV irradiation showed PASE and PI structures, respectively. These films exhibited high thermal stability higher than 230°C, which are desirable for waveguide fabrication for optical inter-connects and lightwave circuits. Using this hybrid material, channel-type optical waveguides were successfully fabricated by the single-step photo-patterning procedure without development by aqueous or organic solvents, which is more facile and economical for waveguide mass-fabrication

Midterm surgical results of total cavopulmonary connection: clinical advantages of the extracardiac conduit method

AbstractObjectiveWe evaluated the midterm surgical outcomes of intra-atrial lateral tunnel and extracardiac conduit total cavopulmonary connection to clarify the clinical superiority.MethodsPatients (n = 167) underwent total cavopulmonary connection (88 with lateral tunnel and 79 with extracardiac conduit) from November 1991 to March 1999. Survival, incidence of reoperation and late complications, exercise tolerance, hemodynamic variables, and plasma concentration of natriuretic peptide type A were compared. In the lateral tunnel group, time-related change in lateral tunnel size was investigated for its relationship to postoperative arrhythmias.ResultsThe 8-year survival was 93.2% in the lateral tunnel group and 94.9% in the extracardiac conduit group. Seven reoperations were performed in the lateral tunnel group but none in the extracardiac conduit group. Supraventricular arrhythmias developed in 14 patients (15.9%) in the lateral tunnel group and in 4 patients (5.1%) in the extracardiac conduit group (P = .003). Freedom from cardiac-related events was 72.5% in the lateral tunnel group and 89.8% in the extracardiac conduit group at 8 years (P = .0098). Hemodynamic variables and exercise tolerance were similar in both groups but plasma natriuretic peptide type A concentration, a parameter of atrial wall tension, was higher in the lateral tunnel group. In the lateral tunnel group, intra-atrial tunnel size increased by 19.4% during the 44.2-month interval and the percent increase in tunnel size was an independent predictor of supraventricular arrhythmias.ConclusionsThe midterm survival, hemodynamic variables, and exercise tolerance were similar and satisfactory in both lateral tunnel and extracardiac conduit groups; however, the incidence of cardiac-related events was significantly less frequent in the extracardiac conduit group. In the lateral tunnel group, careful observation is required to monitor the relationship of the dilating tendency of the intra-atrial tunnel and the development of late complications

Cathepsins B and L in synovial fluids from patients with rheumatoid arthritis and the effect of cathepsin B on the activation of pro-urokinase

To clarify the pathophysiological role of cathepsins in rheumatoid arthritis (RA), we investigated whether cathepsin B or cathepsin L was increased in synovial fluid (SF) of RA joints, and whether the cathepsin isolated from SF of RA patients activated pro-urokinase or not. Thus, we estimated the content of cathepsins in SF of RA patients by measuring their activities by fluorospectrometry, using Z-Phe-Arg-MCA as the substrate. Cathepsin activity was approxymately 4-fold higher in the SF of RA patients than in those of patients with osteoarthritis. Cathepsin B and cathepsin L were separated by cation-exchange column chromatography. As a result, a large peak corresponding to cathepsin B and a very small peak correponding to cathepsin L were detected. Biochemical sequential fractionation of the cathepsin purified from the SF showed that the large peak was mainly composed of cathepsin B. This purified enzyme induced conversion of pro-urokinase to urokinase, and the Km for pro-urokinase was approximately 8.27μM. These findings indicated that an imbalance between cathepsin B and its inhibitors occurred due to increased concentrations of active cathepsin B in RA articular lesions, and that cathepsin B might be related to the degradation of cartilage in RA by activating the fibrinolytic cascade

Tobacco Root Endophytic Arthrobacter Harbors Genomic Features Enabling the Catabolism of Host-Specific Plant Specialized Metabolites

Plant roots constitute the primary interface between plants and soilborne microorganisms and harbor microbial communities called the root microbiota. Recent studies have demonstrated a significant contribution of plant specialized metabolites (PSMs) to the assembly of root microbiota. However, the mechanistic and evolutionary details underlying the PSM-mediated microbiota assembly and its contribution to host specificity remain elusive. Here, we show that the bacterial genus Arthrobacter is predominant specifically in the tobacco endosphere and that its enrichment in the tobacco endosphere is partially mediated by a combination of two unrelated classes of tobacco-specific PSMs, santhopine and nicotine. We isolated and sequenced Arthrobacter strains from tobacco roots as well as soils treated with these PSMs and identified genomic features, including but not limited to genes for santhopine and nicotine catabolism, that are associated with the ability to colonize tobacco roots. Phylogenomic and comparative analyses suggest that these genes were gained in multiple independent acquisition events, each of which was possibly triggered by adaptation to particular soil environments. Taken together, our findings illustrate a cooperative role of a combination of PSMs in mediating plant species-specific root bacterial microbiota assembly and suggest that the observed interaction between tobacco and Arthrobacter may be a consequence of an ecological fitting process

Magnetic design for an electrodeless discharged lamp

We proposed an analysis method for plasma in an electrodeless discharged lamp light-emitting by inductively-coupled plasma, and a design of a power coupler was investigated by focusing on the electric power from the exciting coil to the plasma. We found that the power of the plasma was increased and of an Al stage was decreased with moving the core upward. This result suggests that the moving of the core upward is effective to reduce wasted power loss by eddy current and improves the lamp efficiency. In order to verify the result, we changed the position of the power coupler in the commercial lamp. Resultantly, the luminous flux of the lamp was increased by approximately 150 lm (lumen), when the power coupler was moved upward by 25 mm compared with the position of a commercial lamp. Therefore, we can conclude that our proposed method is applicable to the design of the lamp and suitable design is important to obtain high lamp efficiency

Hemobilia Derived from Cystic Artery Pseudoaneurysm

Cystic artery pseudoaneurysm (CAP) is a rare disease, with small number of previous reports related to CAP. Besides, it is frequently prone to critical condition due to arterial bleeding. Here, we presented a case of ruptured CAP with acute calculus cholecystitis and its subsequent successful management with temporary endoscopic biliary drainage for obstructive jaundice and embolization for the culprit artery without cholecystectomy. Since CAP is at high risk of bleeding, intravascular treatment, which is only one currently available therapeutic option, is urgently required in the clinical sites