Continuous hydrogen evolution from cyclohexanes over platinum catalysts supported on activated carbon fibers

The continuous production of hydrogen from cyclohexanes is achieved effectively using Pt/ACF (ACF = activated carbon fiber) catalysts in a fixed-bed flow reactor. The Pt catalysts are more effective than a Pd/ACF catalyst for the reaction. Besides cyclohexane, methylcyclohexane, 1,4-dimethylcyclohexane, and p-menthane can also be employed as hydrogen source in the reaction system.     

Effect of sulfasalazine on B cell hyperactivity in patients with rheumatoid arthritis

OBJECTIVE: We investigated the in vitro immunomodulatory effects of sulfasalazine on B cells in rheumatoid arthritis (RA). METHODS: Reversed hemolytic plaque assay and 3H-thymidine incorporation were measured. RESULTS: B cells from patients with RA showed hyperactivity to stimulation by Staphylococcus aureus Cowan I. Sulfasalazine significantly inhibited this B cell hyperactivity in a dose dependent manner. The kinetic study and a decrease in 3H-thymidine incorporation on Day 3 indicate that sulfasalazine inhibited the early phase (0-48 h) of B cell proliferation in these patients. Sulfapyridine also inhibited B cell hyperactivity in these patients, but 5-aminosalicylic acid and N-acetylsulfapyridin had no significant effect. CONCLUSION: Sulfasalazine exhibited a direct immunosuppressive effect on B cell hyperactivity in patients with RA, which may be responsible for its therapeutic effectiveness in this disorder.     

Structural characterization of a new galactofuranose-containing glycolipid antigen of Paracoccidioides brasiliensis

An acidic glycolipid (Band 1), purified from P. brasiliensis by a combination of ion exchange chromatography, HPLC, and HPTLC, was found to be reactive with sera of all patients with paracoccidioidomycosis (PCM). Monosaccharide analysis of Band 1 yielded mannose and galactose in a 2:1 ratio, while mild acid hydrolysis and mild periodate oxidation/NaB3H4 reduction indicated the presence of a terminal galactofuranose. Preliminary analysis of 1H-NMR and MS data suggests that the structure of the glycan is Galf beta 1-->6(Manp alpha 1-->3)Manp beta 1-->2Ins (Ins = myo-inositol). Removal of the galacto-furanose decreased by 60-80% the reactivity of sera from PCM patients with Band 1, suggesting that this residue is immunodominant. With the presumed absence of galactofuranose in mammalian hosts, compounds containing this residue may be useful targets for therapy of several parasitic and fungal diseases.     

Superovulatory responses in Japanese black beef cows following largest follicle aspiration or human chorionic gonadotrophin (hCG) treatment

The effect of largest follicle aspiration or hCG administration before induction of superovulation on the ovarian response of Japanese Black beef cows was investigated using a crossover design in which induction of superovulation was attempted in every cow. The superovulatory response of cows whose largest follicle had been aspirated from the ovaries by ultrasound-guided follicular aspiration 1 day before induction of superovulation, did not differ from the response in non-treated control cows. In contrast, in cows given 5,000 IU of hCG 3 days before induction of superovulation, the proportions of fertilized ova and transferable embryos significantly decreased compared with the other groups.     

A 20 GHz 8 bit multiplexer IC implemented with 0.5 μm WNx/W-gate GaAs MESFET's

An ultrahigh-speed 8 bit multiplexer (MUX) has been developed for future-generation optical-fiber communication systems having a data rate of 20 Gb/s. This IC was fabricated using a 0.5 μm WN_x/W-gate GaAs MESFET process based on optical lithography, ion implantation, and furnace annealing for good reproducibility and high throughput. The WN_x/W bilayer gate has a low sheet resistance, improving the circuit high frequency performance. To attain 20 GHz operation, advanced circuit techniques for the source-coupled FET logic (SCFL) were introduced. A cross coupled source-follower (CCSF) was developed mainly for the highest speed buffers to enhance the bandwidth. The first-stage T-type flip-flop was designed with optimization techniques and operated up to 21.1 GHz     

Inhibition of demecolcin-induced DNA synthesis by inhibitors of phospholipase C and protein kinase C

PURPOSE OF STUDY: Interleukin-2 (IL-2) is a potent activator of lymphocytes, but its effectiveness as an anti-cancer agent is compromised by several adverse side effects including pulmonary edema. One explanation for the pulmonary toxicity of IL-2 is that activated lymphocytes directly induce the pulmonary vascular endothelium to become more leaky. METHODS: To test this hypothesis the number of total lymphocytes, gamma delta T cells, and CD2-positive cells (alpha beta T cells and natural killer cells) in peripheral blood and lung lymph of sheep were compared before and after IL-2 infusion. Hemodynamic and lymph dynamic changes were also evaluated. RESULTS: IL-2 decreased mean aortic pressure, increased cardiac output, lowered systemic vascular resistance, and doubled lung lymph flow (P < or = 0.05), but had no effect on plasma or lymph oncotic pressure. The lymph protein concentration and the lymph-to-plasma protein concentration ratio were not different after IL-2 infusion. IL-2 had no effect on the number of total lymphocytes, gamma delta T cells, or CD2-positive cells in the peripheral blood. In contrast, the number of total lymphocytes, gamma delta T cells, and CD2-positive cells in lung lymph decreased significantly (P < or = 0.05). CONCLUSIONS: The lymphocyte populations decreased more than could be explained by the increase in lymph flow, demonstrating that lung lymphocytes were not reduced simply by dilution. These results imply that the pulmonary edema associated with IL-2 is not caused by activated lymphocytes.     

Minor role of fractographic features in basic fatigue crack propagation properties

The fatigue crack propagation rate and the fatigue threshold were investigated for transverse-butt-welded joints of the austenitic stainless steel SUS304. Specimens were of the center-cracked type. In three sets of tests the fatigue crack passed through the weld metal, and in the other two sets, through the base metal. The fatigue crack propagation properties coincided with each other at different stress ratios for the weld metal, and at the higher stress ratios for the base metal. The propagation properties improved at the stress ratio of zero for the base metal. The absence of a stress ratio effect means that the coincided properties are basic ones in which fatigue crack closure does not occur. However, fractographic appearance and surface roughness were quite different between weld metal and base metal. The coincidence of fatigue crack propagation properties in spite of the difference in fractographic features reveals that the fractographic appearance and surface roughness only have a minor effect on basic fatigue crack propagation behaviour.     

Cloning, functional expression and tissue distribution of rabbit alpha 1d-adrenoceptor

We attempt to determine the utility of CERAD in detecting early Alzheimer's disease (AD). CERAD battery was administered to a group of 14 control subjects, 12 patients with possible dementia prodromes and to patients with Alzheimer's disease stratified according to severity (16 mild, 8 moderate). Other measures as some subtest of the Wechsler memory scale and the Rey Complex Figure Test were also applied. Delayed recall as well as logical memory of Wechsler memory scale were found to be the best discriminators for detecting very mild cases of AD (Prodromes) (p < 0.05). None of the memory test proved of value in staging the disorder. Visuospatial functions are better determinants of the progression of the illness. Fluency also distinguish between control subjects and very mild cases. These findings suggest that delayed recall memory and probably executive function are the most useful and sensitive indicators of Alzheimer's disease.     

Development of a Cyclogyro-Based Flying Robot With Variable Attack Angle Mechanisms

This paper presents an experimental study on the development of a cyclogyro-based flying robot with a new variable angle of attack mechanism. A cyclogyro is a flying machine supported in the air by power-driven rotors that rotate about a horizontal axis, like the paddle-wheels of a steamboat. Machines of this type have been designed by some companies but there has been no record of any successful flights. Our design starts with a new variable angle of attack mechanism with an eccentric (rotational) point in addition to a rotational point connecting to a motor. The main feature of the mechanism with the eccentric rotational point is the ability to change attack of angles in accordance with the wing positions (as determined by the rotational angles of the cyclogyro) without actuators. The design parameters (wing span, the number of wings, and eccentric distance) of the flying robot are determined through a series of experiments. Experimental results show that the cyclogyro-based flying robot with the new variable angle of attack mechanism is capable of generating sufficient lift force for flying.