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Aluminum alloys have been widely used for automobile and aircraft parts. In cutting of aluminum alloy, adhesion sometimes occurs to deteriorate surface finish. The study discusses the adhesion characteristics in drilling of aluminum alloy (A7075) with a flat tool at a point angle of 180 degrees. The adhesion volumes on the rake face of the tool were measured in drillings of blind holes for the cutting speeds and the feed rates. Then, the stress and the temperature distributions were estimated in the cutting simulation. In the simulation, the cutting force is predicted in the chip flow model based on the minimum cutting energy. The cutting temperature is analyzed in Finite volume method using the result in the cutting force prediction. The adhesion volumes are associated with the stress and temperature on the rake face. The adhesion volume becomes large in the temperature ranged from 400 to 500 K. The adhesion volume increases with the stress up to 500 MPa.

Hepatocellular carcinoma often arises in cirrhotic livers. Patients with severe liver cirrhosis who undergo hepatectomy often develop postoperative liver failure, even if the hepatectomy is limited. Here, we report six patients with severe liver cirrhosis (Child-Pugh B/C and indocyanine green retention rate at 15 min ≥ 40%) who underwent pure laparoscopic hepatectomy. Their perioperative course was favorable and comparable to that of other hepatocellular carcinoma patients with mild-moderate liver cirrhosis. In patients with severe liver cirrhosis, pure laparoscopic hepatectomy minimizes the disturbance in collateral blood and lymphatic flow caused by laparotomy and liver mobilization, as well as the mesenchymal injury caused by compression of the liver. It limits complications such as massive ascites, which can lead to severe postoperative liver failure. Good candidates for the procedure include patients with severe liver cirrhosis who have tumors on the liver surface and in whom adaptation to ablation therapy is difficult and/or who experience local recurrence after repeat treatments.

Purpose To assess the association between serum total bilirubin levels and diabetic retinopathy prevalence in participants of the Hisayama Study who had diabetes and impaired glucose metabolism. Design Population-based, cross-sectional study. Participants Of 3119 participants of the Hisayama Study Eye Examinations in 2007, Japan, 1672 aged ≥40 years with either diabetes or impaired glucose metabolism (defined by a 75-g oral glucose tolerance test) were enrolled in the present study. Methods Diabetic retinopathy was assessed via ophthalmic examination after pupil dilatation. The presence and the severity of diabetic retinopathy were determined by grading of color fundus photographs using the modified Airlie House classification system. Association of diabetic retinopathy with serum bilirubin quartiles was assessed using logistic regression model adjusting for age and known risk factors for diabetic retinopathy. Main Outcome Measures Prevalent diabetic retinopathy. Results Diabetic retinopathy was present in 70 of 1672 (4.2%) participants. The prevalence of diabetic retinopathy in persons with the highest bilirubin quartile (≥0.9 mg/dL) was 2.7%, compared with the prevalence of 3.4%, 5.1%, and 5.1% in those with the first ( Conclusions Elevated serum bilirubin levels may be protective against diabetic retinopathy among persons with either diabetes or impaired glucose metabolism, independent of known risk factors for diabetic retinopathy. Financial Disclosure(s) The authors have no proprietary or commercial interest in any of the materials discussed in this article.

Designing stem cell transplantation (SCT) conditioning regimens for Fanconi anemia (FA) has proved difficult because of hypersensitivity to the DNA cross-linking agents. We performed chromosome fragility tests with 56 FA patients and with 50 non-FA patients with severe aplastic anemia or myelodysplastic syndrome. We evaluated peripheral blood lymphocyte specimens cultured for 72 hours and treated with mitomycin C, diepoxybutane (DEB), cyclophosphamide (CY) metabolites, cytosine arabinoside (Ara-C), and fludarabine (Flu) metabolite (9-beta-D-arabinofuranosyl-2-fluoroadenine [2-F-Ara-A]). The DEB and CY metabolite tests were highly sensitive and specific for FA (P10(-4)) for both tests), and the number of aberrations per cell for DEB correlated with that for the CY metabolite test (P10(-4)) but did not correlate with the number of aberrations per cell for the Ara-C and 2-F-Ara-A tests. The difference in breakage frequencies between FA and non-FA patients for cultures treated with 2-F-Ara-A was not statistically significant. Most of the breakages observed in cells treated with 2-F-Ara-A-and Ara-C were chromatid breaks. It may be possible to determine the appropriate CY dose in the preconditioning regimen for SCT in FA patients on the basis of the in vitro effects on fragility, and Flu or Ara-C may be a safer drug than high-dose CY for conditioning in FA patients.

Selective growth of AlGaInAs/InP on masked substrate is investigated by low-pressure metalorganic chemical vapor deposition (MOCVD). Tetrabromocarbon (CBr 4 ) is introduced into the reactor during epitaxial growth as etching gas. The etching action of CBr 4 on AlGaInAs grown on planar substrate only affects In atoms, and has little influence on Al and Ga. Selective area growth of AlGaInAs multi-quantum wells (MQWs) on masked substrate is carried out by introducing CBr 4 during growth of Al-containing layers except wells. Polycrystals on the dielectric mask decrease with CBr 4 flow rate and complete selectivity is achieved with CBr 4 flow rate of 3.2 μmol/min when the growth temperature and the growth rate are 680°C and 30 nm/min, respectively, which correspond to our optimum condition for the growth of AlGaInAs. From the results of photoluminescence and broad-type laser diode of MQW, the introduction of CBr 4 does not seem to degrade the crystallinity of AlGaInAs/InP.

揮発性有害大気汚染物質の平均濃度をキャピラリーカラムGC/MSで長期間観測するための試料導入方法を検討した。平均濃度を求めるために, 2つの試料採取容器に試料を交互に採取し測定をおこなった。これにより分析周期の如何に関わらず試料採取を連続して行うことが可能となった。測定回数を減らすことで少ないデータで平均濃度を効率よく求めることが可能となった。

A 1.3 /spl mu/m Al-oxide confined inner stripe laser on p-InP substrate (PACIS) has been demonstrated for low cost laser array application. First, we have investigated the oxidation rate of Al/sub x/In/sub 1-x/As layer grown on InP substrate. The optimum conditions were found to be oxidation temperature=500/spl deg/C, layer thickness=100 nm, and Al-contents=0.48 (lattice-match) taking oxidation rate and surface morphology into account. The 50 nm-thick Al/sub 0.48/In/sub 0.52/As-oxide layer provides good current blocking for laser applications. Based on the above investigations, the fabricated PACIS laser shows a low threshold current of 4.0 mA and a high slope efficiency of 0.6 W/A. We have also confirmed high reliability under driving time over 3,000 hours at 85/spl deg/C, 5 mW. A 22-channel laser array consisted of PACIS structure have the average threshold current of 3.98 mA and the standard deviation of 0.42 mA.

Mode field converter (MFC) integrated 1.3 /spl mu/m GaInAsP laser diode with a monitoring photodiode through a semiconductor/air Bragg reflector (SABAR) has been successfully demonstrated. Instead of conventional cleavage, the SABAR can provide not only Fabry-Perot resonance with high reflectivity, but also possibility of integration of laser with the other functional devices. We have obtained a threshold current of 22 mA in the followed laser structure (L=270 /spl mu/m, W=7 /spl mu/m, SABAR pairs N=1), and detector photocurrent of 1.13 mA (@5 mW). The experimental SABAR reflectivity is 50%, which is estimated by threshold characteristics and efficiency of light output power. The laser has a mode field converter (MFC) section, resulting in narrow beam divergence 11/spl deg/ along vertical axis. This integrated laser is very promising candidate for coming optical module in low power consumption and low cost access network systems.

We have investigated oxidation rate of an AlInAs layer grown on InP substrate. It is found that oxidation rate in Al/sub x/In/sub 1-x/As layer increases with temperature and layer thickness, and shows no dependence on Al-content in the range of 0.48 (lattice-match) to 0.7. The electrical characteristics of 50 nm-thick AlInAs-oxide shows good current blocking for laser application. The optimum temperature was found to be around 500/spl deg/C, taking oxidation rate and surface morphology into account. AlInAs-oxide confined inner stripe laser (ACIS) is fabricated for the first time.

In conclusion, 980 nm lasers using strained GaInAsP QW lasers have been fabricated by MOCVD for the first time. Low threshold and high power operation have been obtained.

In-situ etching of GaInAsP/InP and AlGaInAs/InP double-heterostructures in a MOCVD reactor was carried out with carbon tetrabromide (CBr/sub 4/). The InP layer was easily etched with proportion to the amount of CBr/sub 4/, and a smooth surface was obtained after etching. On the contrary, it was difficult to etch the GaInAsP layer and many residues were observed. The AlGaInAs layer was not etched at all and it was concluded that the AlGaInAs layer could be used as an etching-stop layer. When an epitaxial layer was successively grown after in-situ etching, a high-quality regrowth interface, such as reduced defects and oxygen concentration, was obtained.

A novel disordering technique of multiple quantum wells (MQWs) is realized by a layer structure consisted of n-InP/p-InP/GaInAsP MQW (/spl lambda/g=1.5 /spl mu/m) grown by MOCVD. The emission wavelength of the MQW shifts to the shorter side under the existence of a n-InP cap layer. The energy shift becomes larger with increase of growth temperature and thickness of the n-InP cap, and reaches as large as 130 meV (1500 nm->1300 nm) at 650/spl deg/C and 3000 nm, respectively. From the depth profile measured by secondary ion mass spectroscopy, interdiffusion of group V elements (As and P) between well and barrier is the origin of the blue shift.

A technique for lead discovery vs RNA targets utilizing mass spectrometry (MS) screening methods is described. The structure-activity relationships (SAR) derived from assaying weak binding motifs allows the pharmacophores discovered to be elaborated via "SAR by MS" to higher affinity ligands. Application of this strategy to a subdomain of the 23S rRNA afforded a new class of compounds with functional activity.

A mixture-based combinatorial library of 14-membered macrocycles was synthesized to target ribosomal RNA and uncover a new class of antibacterial agents. High-throughput screening identified a macrocyclic mixture that inhibited cell-free-coupled transcription/translation in Escherichia coli-derived extracts, with an IC(50) value in the 25-50 microM range. In a follow-up library of 64 single macrocycles, 8 gave IC(50) values ranging from 12 to 50 microM in the cell-free protein synthesis inhibition assay. Some of the macrocycles were screened in a translation inhibition assay, and IC(50) values generally paralleled those obtained in the uncoupled transcription/translation assay. Additional analogues were prepared in a preliminary structure-activity relationship study, and more potent macrocycles were identified with low micromolar activity (IC(50) values = 2-3 microM). Some of these macrocycles displayed antibacterial activity against lipopolysaccharide mutant E. coli bacterial cells (IC(50) values = 12-50 microM).

1.3 /spl mu/m Al-oxide confined inner stripe lasers and laser arrays on p-InP substrate (PACIS) have been fabricated as light sources for parallel data transmission. An Al/sub 0.48/In/sub 0.52/As layer lattice-matched to InP is used as the oxidised layer. A fabricated PACIS laser shows a low threshold current of 4.0 mA and a high slope efficiency of 0.6 W/A, resulting from the good current blocking characteristics of the oxidised layer. High reliability over a driving time of >4000 h at 85/spl deg/C, 5 mW has been realised. A 22-channel PACIS laser array has an average threshold current of 3.98 mA with standard deviation of 0.42 mA.

The authors have fabricated a 1.3 /spl mu/m GaInAsP strained-layer QW (Al-oxide confined inner stripe) laser on a p-InP substrate using an AlInAs-oxide layer for the first time. A low threshold current of 6.8 mA, a high slope efficiency of 0.55 W/A and single lateral mode operation were obtained. Both low threshold and single lateral mode operations indicate that real-index inner stripe structure could be realised using AlInAs-oxide.

Absorption, distribution, excretion and metabolism of [3H]gliclazide, N-(3-3H-4-methylbenzenesulfonyl)-N′-(3-azabicyclo-[3,3,0]oct-3-yl]urea, a new hypoglycemic agent possessing unique pharmacological properties, were studied by radiometry and autoradiography in rats after oral administration in 10 mg/kg.

A combined use of deuterium labelling and recently developed scanning thinlayer chromatography/matrix-assisted-secondary-ion mass spectrometry(TLC/SIMS) was applied for identification of metabolites of zonisamide in rat urine. Zonisamide with deuterium distribution of d2/d3/d4=1/2/1 were prepared and orally given to rats at the dose of 40 mg/kg. Metabolites were extracted from 48 hr-urine and subjected to TLC/SIMS. The specific distribution of deuterium made easy the identification of the urinary metabolites by simple inspection of the spectrum for the presence of triplet ion clusters.In rat urine unchanged drug and three metabolites, N-acetyl-3-sulfamoylmethyl-1, 2-benzisoxazole, 1, 2-benzisoxazoel-3-carboxylic acid, and the sulfate of (2-hydroxybenzoyl)methanesulfonamide, were identified, and the presence of a polar conjugate of unchanged drug was suggested. Cleavage of N-O bond in benzisoxazole ring was demonstrated.

Infrared studies of the copolymers in a chloroform solution have revealed that, in each series of copolymers, the transition from the left- to the right-handed α-helix simultaneously brings about sharp changes in the characteristic amide frequencies. The frequencies of the NH-stretching, amide I, and amide II bands of the copolymers in the left-handed α-helix are higher by ca. 13 cm−1, ca. 10 cm−1, and ca. 5 cm−1 respectively than those in the right-handed α-helix. The amide bands of the copolymers in the right-handed form lie in the normal frequency ranges as established for α-helical polypeptides. On the contrary, the amide frequencies of poly-β-benzyl-L-aspartate or the copolymers in the left-handed form are anomalous. The anomalous amide frequencies of the lefthanded helix are to be ascribed to the reversal in the helical sense, but not to the particular aspartate group, since the copolyaspartate esters in the right-handed helix exhibit normal amide frequencies. The transition in the helical sense is ...

A new high-performance liquid chromatographic procedure is described for the simultaneous determination of plasma and urinary uric acid, xanthine, hypoxanthine, allopurinol, oxipurinol, orotic acid and orotidine whose quantities are varied by allopurinol treatment in man. Creatinine was also measurable. The method was established by high-performance liquid chromatography and gas chromatography—mass spectrometry.

Following intraperitoneal administration to rats of [14C]loperamide, [carbonyl-14] 4-(p-chlorophenyl)-4-hydroxy-N,N-dimethyl-alpha, alpha-diphenyl-1-piperidine butyramide, metabolites in feces and urine were separated, and identified by means of mass spectrometry. In feces, six metabolites were identified in addition to the unchanged drug. The main metabolic pathways involved are dealkylation in the dimethyl amide moiety to give desmethyl- and didesmethylloperamide, both of which were in turn monohydroxylated either in the alpha-phenyl ring or possibly in the alpha-carbon in the piperidine ring. It is noteworthy that metabolites hydroxylated in the piperidine ring were isolated as pyridinium derivatives, possibly due to spontaneous aromatization of its 2,4-dihydroxy-4-(p-chlorophenyl)piperidine ring. In urine, only two metabolites were found and identified to be desmethyl- and didesmethylloperamide, since [14C]loperamide was excreted into urine only in a small amount.