Chemical (Sr,Co)-doping effect on critical current density for Dy123 melt-solidified bulks

The dilute impurity doping for CuO-chain site was found to largely improve the critical current properties of both Y123 single crystals and Y123 melt-solidified bulks in our previous study. In addition, dilute Sr-doping to Ba site is also effective for enhancement of J_c without serious decrease in T_c as in the case of dilute Zn doping for CuO₂-plane site. In the present study, we have attempted further enhancement of flux pinning force of the Dy123 melt-solidified bulk, which is essentially more promising materials than Y123, by impurity doping for Cu site in the CuO-chain and for Ba site. Although the (Sr,Co)-co-doped Dy123 melt-solidified bulks showed systematically suppressed T_c with their doping levels, high T_c's well exceeding 90 K were maintained. All the Sr-doped or Co-doped Dy123 bulks exhibited higher J_c than the undoped one. More improved J_c properties were achieved by (Sr,Co)-co-doping, suggesting that pinning potential at local regions around doped impurities become deeper by Co-doping, resulting in stronger point-defect-like pinning sites. In addition, more detailed studies on the dilute Sr-doping and the dilute (Sr,Co)-Co-doping were carried out for Y123 single crystals in order to clarify the difference between their doping effects on the J_c properties. The vortex transition field, H^*, to the disordered state in the M–H loops for the Co-doped Y123 single crystal was located at the lower field than that of the Sr-doped one, meaning that the Co ions strongly affect the vortex system compared with the Sr ions.     

Association of mineral metabolism factors with all-cause and cardiovascular mortality in hemodialysis patients: the Japan dialysis outcomes and practice patterns study

Abnormalities in mineral metabolism have been linked to mortality in hemodialysis (HD) patients. We postulated that these abnormalities would have a particularly large deleterious impact on deaths due to cardiovascular causes in Japan. This study describes the recent status of abnormal mineral metabolism, significant predictors, and potential consequences in the Dialysis Outcomes and Practice Patterns Study (DOPPS), Phases 1 and 2, in Japan. Major predictor variables were patient demographics, comorbidities, and laboratory markers of mineral metabolism such as albumin-adjusted serum calcium (calciumAlb), phosphorus, and intact PTH (iPTH). In a cross section of 3973 Japanese HD patients in DOPPS I and II, a large faction had laboratory values outside of the recommended Kidney Disease Outcomes Quality Initiative (K/DOQI) guideline range for serum concentrations of phosphorus (51% of patients above upper target range), calciumAlb (43.7% above), calcium-phosphorus (Ca x P) product (41.1% above), and iPTH (18.6% above). All-cause mortality was significantly and independently associated with calciumAlb (relative risk [RR]=1.22 per 1 mg/dL, p=0.0005) and iPTH (RR=1.04 per 100 pg/mL, p=0.04). Cardiovascular mortality was significantly associated with calciumAlb (RR=1.28, p=0.02), phosphorus (RR=1.13 per 1 mg/dL, p=0.008), Ca x P product (RR=1.07 per 2 mg(2)/dL(2), p=0.002), and PTH (RR=1.08, p=0.0001). This study expands our understanding of the relationship between altered mineral metabolism and mortality outcomes, showing slightly stronger associations with cardiovascular causes than observed for all-cause mortality. These findings have important therapeutic implications for Japanese HD patients.     

Differential expression of costimulatory molecules in chronic inflammatory periodontal disease tissue

OBJECTIVES: To present the technique of the extended subcranial approach to the anterior skull base and to review the results in 55 patients who underwent the procedure. STUDY DESIGN: Retrospective review of the records of 55 patients who underwent the extended subcranial approach to the anterior skull base between 1994 and 1998 for the treatment of various neoplasms originating in the nasal cavity, nasopharynx, paranasal sinuses, orbit, or meninges, as well as for the repair of complex craniofacial trauma and/or cerebrospinal fluid (CSF) leak. Preoperative patient evaluation and the surgical technique are also reviewed. METHODS: Patient records were retrospectively reviewed and tabulated for age, sex, and indications for procedure, with special focus on early outcome and complications. RESULTS: Twenty-six patients underwent oncologic resections, 22 patients had reduction of complex fronto-naso-orbital and skull base fractures, and seven patients had repair of CSF leak. Significant complications in the oncologic group consisted of one hematoma requiring needle aspiration and two cases of temporary nontension pneumocephalus. In the fracture group, one patient died because of extensive intracerebral damage and multiorgan failure, and one patient had nontension pneumocephalus coupled with CSF leakage and one patient had temporary nontension pneumocephalus. The most common late complication in all three groups was anosmia. CONCLUSIONS: Based on their review, the authors conclude that the extended subcranial approach to the anterior skull base is a safe, versatile, and effective procedure for the surgical treatment of various pathological conditions involving the anterior skull base.     

An accurate center frequency tuning scheme for 450-KHz CMOS Gm-C bandpass filters

This paper describes a center frequency tuning technique for a second intermediate-frequency (IF) bandpass filter. The utilization of the step signal response ensures the direct measurement of the center frequency. This tuning technique guarantees the accuracy of the design. A 450-kHz G_m-C bandpass filter tuned using this technique has been developed to integrate the IF module for personal digital cellular (PDC) handsets for use in 0.35-μm CMOS. The filter with the tuning scheme achieves a center frequency accuracy of ±0.5%     

Ab initio molecular orbital calculations of the NMR chemical shieldings for mannose and mannobiose

The ¹³C and ¹H NMR shielding constants for -methylmannose and -methylmannobiose have been calculated using the ab initio gauge-including atomic orbital (GIAO) method to study the conformational dependencies of the NMR chemical shifts of the sugars. The molecular structures were fully optimized using B3LYP/6-31G^* and the NMR shielding constants were calculated at both Hartree–Fock (HF) and density functional (DF) levels of theory with various kinds of basis sets. The values determined using the B3LYP hybrid functional were a little closer to those obtained experimentally than those determined at the HF level. Both, HF and B3LYP with the 6-311+G(2d,p) basis were found to give a very good correlation between the experimental and calculated shielding constants, especially for ¹³C.     

Investigation of shielding method of ELF magnetic field generated from conductors

We have studied experimentally the shielding method of ELF magnetic field applied to the source of line conductors. For the single‐phase line current, it appears to be difficult to achieve effective shielding. On the other hand, for the balanced three‐phase conductors, including triangle and twisted configuration, a certain reduction of generated magnetic field was achieved by adjusting the configuration of conductors or by surrounding the conductors with cylindrical shielding materials made of ferromagnetic materials or nonferromagnetic metals. Normalized characteristics between phase current, distance between source current and observation point, distance between phase conductors, and the pitch of twisted cable were derived. In addition, the effect of unbalanced current was also investigated. © 2000 Scripta Technica, Electr Eng Jpn, 131(2): 12–19, 2000     

Synthesis of 2H‐Thiopyrans by Rhodium(II) Acetate‐Catalyzed Reaction of 4‐Amino‐2,5‐dihydro‐3‐thiophenecarbonitriles with α‐Diazocarbonyl Compounds. Part 1

4‐Amino‐2,5‐dihydro‐3‐thiophenecarbonitriles 1 reacted with dimethyl diazomalonate in the presence of rhodium(II) acetate to give regioselectively 4‐cyano‐2H‐thio‐pyrans 2 (C ₂— S insertion), and 5‐cyano‐2H‐thiopyrans (C ₅— S insertion) were not isolated. Similar insertion was also observed in the reaction of 1 with methyl diazoacetoacetate and ethyl diazobenzoylacetate. The starting compounds 1 were synthesized by the reaction of tetrahydro‐4‐oxo‐3‐thiophene‐carbonitrile with morpholine, piperidine, and pyrrolidine in the presence of formic acid in ethanol.     

Rhodium(II) acetate-catalyzed Reaction of 2-Amino-4,5-dihydro-3-furancarbonitriles with α-Diazo-β-keto Esters

2-Amino-4,5-dihydro-3-furancarbonitriles ( 1 ) react with α-diazo-β-keto esters in the presence of rhodium (II) acetate to give alkyl 2H-pyran-2-carboxylates ( 2 ) in good yields. Benzoylation of 2 with benzoyl chloride provided alkyl 3-benzoylimino-2H-pyran-2-carboxylates ( 4 ). The formation of 2 could be explained by a mechanism involving an oxonium ylide derived from the rhodium carbenoids and 1 .     

Fluorescent in situ hybridization in combination with filter cultivation (FISHFC) method for specific detection and enumeration of viable Clostridium perfringens

To reduce time for enumeration of viable Clostridium perfringens, fluorescence in situ hybridization in combination with filter cultivation (FISHFC) was employed. The method utilized a CLP-180 probe, based on the 16S rRNA region of C. perfringens, and FISHFC fluorescence microscopy to detect C. perfringens, but not organisms from other species. Optimal cultivation requirements for micro-colony formation were TSC medium, anaerobic conditions, 37 °C, and incubation for 6 h. Under these conditions, micro-colony diameters reached 100 μm, a size sufficient for hybridization. Enumeration of C. perfringens using the CLP-180-aided FISHFC method was realized in 9 h as compared to 3–5 days required by the conventional plate count method. Moreover, viable C. perfringens counts of food samples from the two methods were not significantly different.     

Preservative effect of combined treatment with electrolyzed NaCl solutions and essential oil compounds on carp fillets during convectional air-drying

The antimicrobial and antioxidant effects on carp fillet samples of treatments with alkaline electrolyzed NaCl solution EW (-) prior to treatment with acidic electrolyzed NaCl solution EW (+) and 1% solutions of the essential oils consisting of 0.5% carvacrol and 0.5% thymol (1% Cv+Ty) were tested. First carp fillet samples were treated with EW (-), then EW (+), followed by 1% (C+T), represented as [EW (-)/EW (+)/1% (Cv+Ty)] for 15 min, during drying at 45 degrees C. Samples were subsequently evaluated by microbiological, chemical and sensory analyses. Microbiological analyses indicated that the initial total microbial counts of samples treated with EW (-)/EW (+), 1% (Cv+Ty) or EW (-)/EW (+)/1% (Cv+Ty) were significantly (p< or =0.05) reduced, compared with the control sample. Treatment with EW (-)/EW (+)/1% (Cv+Ty) gave the strongest overall inhibition of microbial growth when compared to all of the other treatments. The volatile basic nitrogen (VBN) value of samples treated with EW (-)/EW (+)/1% (Cv+Ty) was kept at low level (18.46+/-0.45) until the end of drying period (5 days), compared with control samples (40.33+/-0.58). Treatment with EW (-)/EW (+)/1% (Cv+Ty) during drying significantly reduced the peroxide values (PV) and thiobarbituric acid values (TBA). Sensory evaluation indicated that there were significant differences (p< or =0.05) in the color, odor, taste, flavor and texture, on the end of the 5-day drying period between samples treated with EW (-)/EW (+)/1% (Cv+Ty), as compared to all of the other treatments. We conclude that treatment with EW (-)/EW (+)/1% (Cv+Ty) had stronger antimicrobial and antioxidant effects than all of the other treatments on carp fillets during drying, and could be a good alternative to artificial preservatives in food industry.