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The general three‐dimensional high‐frequency oscillatory flow near a stagnation point is investigated through the method of matched asymptotic expansions. The nonlinear Reynolds's stresses create a steady streaming motion in the fluid. It is found that this streaming is minimized when the surface near the stagnation point is axisymmetric and is maximized when the surface is a saddle.

A rigid rotating cylindrical shaft is vibrating along a diameter in a viscous fluid. Two different cases are investigated through the method of inner and outer expansions. The case of small amplitude vibrations is characterized by the diffusion of vorticity. The coupling of rotation with vibration introduces a normal force, of both inviscid and viscous origins, perpendicular to the direction of oscillation. As rotation increases, the induced steady streaming becomes more skewed and weaker. The case of fast rotation is characterized by the transport of vorticity. Rotation affects both the drag and normal force. The steady torque is increased due to the induction of a steady secondary rotary flow.

Irradiation of 6MU with 254 nm light, 6MU6MU are formed with cis-syn and cis-anti configurations in frozen aqueous solutions and with predominantly cis configurations in frozen t-butanol solutions; no dimerization occurs in methanol “puddles”. Irradiated with 254 nm light, 6MU6MU with predominantly trans configurations are obtained in H 2 O and D 2 O solutions; dimer yields in D 2 O are three times that in H 2 O. Irradiated with 313 nm light, acetone photosensitized dimerization gives only trans-syn and trans-anti dimers. The total dimer yields decrease as the solvent is changed from 90% CH 3 COOH, CH 3 OH, CH 3 CN to non-polar solvent p-dioxane. Our results contradict the general belief that if dipole moment increases in the transition state leading to head-to-head or syn dimers, the dimer yield increases in a solvent with high dipole moment. The study of pH effects indicated that keto-enol equilibrium of 6MU probably controls the dimer yields and distributions of these photosensitized dimerization processes. With 1,3,6- trimethyluracil, the total dimer yields decrease with increasing pH; however, the product compositions remained unchanged over the entire pH range. This finding suggests that the ketonic or protonated ketonic form of an α,β-unsaturated ketone molecule is the favored structure for photodimerization and ketoenol equilibrium influences the compositions of dimers.

Summary Kinetic analysis of the forward and backward reactions of 1,3-dimethyluracil and uridine showed that the rate constants and kinetic orders of the photochemical reactions were strongly dependent upon the substituent groups present in the excited molecules. Thus the irradiation of 1,3-dimethyluracil in aqueous solution with ultraviolet light followed first-order kinetics in 0–1 mM solution, while in 0.5, 1 and 5 mM solutions the reaction was pseudo-zeroth-order. Such a change in the order of reaction is characteristic for a light-dependent reaction. For uridine, the reaction followed first-order kinetics for all concentrations between 0.5 and 10 mM, showing that the dark step may be rate determining. Effect of pH in buffered solution and dilute hydrochloric acid solution, light intensity and temperature on the rate of reactions were studied and are discussed. Quantum yields for the various reactions were calculated. The reconstitution reaction of 1,3-dimethyluracil from 6-hydroxy-1,3-dimethylhydrouracil was first-order in both acid and base catalyzed dehydration. The 6-hydroxyhydrouridine reverted to uridine by a first-order reaction when catalyzed by acid and by a second-order reaction when catalyzed by base.

A circular cylinder in an infinite fluid rotates rigidly about a fixed axis which is parallel to, but does not coincide with, its geometric axis. It is found that, depending on the relative magnitude of the Reynolds number R and eccentricity ε, the flow may have two, one or no boundary layers. General solutions for R [Lt ] are obtained. It is found that owing to eccentricity there exist both a flow periodic in the circumferential direction and a non-periodic flow which is a function only of the radial distance from the centre of the cylinder. The non-periodic flow is caused by the nonlinear Reynolds stress and contributes to the torque experienced by the cylinder. The high Reynolds number case, \[ 1 \Lt R \Lt\epsilon^{-\frac{3}{2}}, \] is solved by matched asymptotic expansions. The stream function can be represented by Hankel functions of order 1/3 and a slight decrease in torque is found. In the low Reynolds number case, R [Lt ] 1, the torque is increased owing to eccentricity when R < 0·145 and decreased when R > 0·145. A physical explanation is presented.

Separation and stall of an impulsively started elliptic cylinder at an angle of attack are investigated through the method of inner and outer expansions. The assumptions are large Reynolds numbers and small times. The interactions between the boundary layer and the outer inviscid flow are taken into consideration. Uniformly valid solutions are obtained for general two-dimensional cylinders. The movements of the separation points on an elliptic cylinder are calculated. Stall is found to be strongly dependent on the thickness ratio and the angle of attack of the cylinder but to be weakly dependent on the Reynolds number.

A hydrodynamic theory for the locomotion of spirochetes is presented. The theory is based on a possible arrangement of internal fibrils such that self rotation about a local body axis is possible. This self rotation is responsible for cancelling the torque produced by the traveling helical waves of the body. The hydrodynamic theory follows the method used by Taylor, but with different boundary conditions. A relationship between the radius of body cross section, amplitude and wavelength of the helical wave is obtained for a spirochete traveling with no apparent slippage of water. The angular velocity of rotation about a local body axis is also determined. The theoretical results compare favorably with direct measurements of body geometry.

Summary Irradiation of uridine in aqueous solution with ultraviolet light gives 6-hydroxyhydrouridine as the first isolable product. 5-Hydroxyhydrouridine, a possible intermediate or product, has been eliminated as involved in this photochemical reaction. The mechanism of the irradiation reaction is thus probably identical to that of 1, 3-dimethyluracil. Improved procedures for the preparation of 5-bromouridine and 5-hydroxyuridine are also presented.

The equations governing high-frequency oscillatory viscous flows are investigated through the separation of the steady and the unsteady parts. All Reynolds number ranges are studied and the orders of magnitude of the steady streaming produced by the Reynolds stresses are established.The oscillating circular cylinder at low Reynolds numbers is studied through the method of inner and outer expansions. Steady recirculating cells exist near the cylinder. The results compare very well with experiments. Analytic expressions for the streamfunction and the drag coefficient are obtained.The oscillating flow towards an infinite plate is investigated in detail. The steady streaming is caused by the steady component of the Reynolds stress. The pressure gradient always causes reverse flow near the solid boundary.

Summary Upon freezing an aqueous solution, the formation of crystalline ice forces the solute molecules into solid aggregates. Therefore, identical photodimerimtion of pyrimidines occur in either frozen aqueous solutions or dry solid films. No photodimerization of pyrimidines was evidenced in a homogeneous glycerol glass. Upon freezing an aqueous solution containing solute and a small percentage of organic solvent, the solute molecules together with some organic solvent form ‘puddles’. Therefore, a photochemical reaction in this organic solvent was observed. Only those pyrimidines having an α,β-unsaturated keto group in their structure undergo photodimerization. The mechanism through which the cyclobutyl ring is formed most probably involves a diradical intermediate. The unstable thymine monohydrate crystal has the most favorable orientation for two thymine molecules to form dimer. Therefore, the photodimerization process for thymine is less favored in dry solid film than in frozen aqueous solution because the thymine monohydrate crystalline lattice collapses under low humidity.

— Uracil, 5-hydroxymethyluracil, and 5-formyluracil have been identified by paper chromatography as the photo-oxidation products from an aqueous solution of thymine which was irradiated with germicidal lamps. These findings are parallel to the photochemical changes of 1,3-dimethylthyniine as reported in the preceding paper.

A sphere is started impulsively in an incompressible viscous fluid of infinite extent. The Reynolds number is assumed to be large. The time of investigation is assumed to be small. The Navier–Stokes equations, written in spherical polar coordinates, are then iterated using the method of inner and outer expansions. Uniformly valid solutions are obtained to second order. The drag is also predicted.

W E are one of the most affluent, and effluent, people in the world. Recent investigations suggest that over a ton per person of various types of solid wastes is collected annually in the United States [4, p. 13] and over one percent of GNP is spent on collection and disposal [2, p. 3]. What are solid wastes? In addition to garbage and municipal refuse, solid wastes include wastes from commercial, industrial, agricultural, and demolition sources. The composition of solid wastes has been changing dramatically over time, and volume has been continuously increasing. Pressing problems connected with this growing amount of material have been recognized in many cities and metropolitan areas, and efforts are being made to find solutions. However, solid waste problems are by no means confined to cities and large metropolitan areas. Failure to recognize solid waste problems in rural areas may be one reason why open dumps, open-dump burning, and littering occur and are making many rural areas lose their advantage over cities in environmental quality. As urban frontiers penetrate deeper into rural areas, solid waste problems in rural areas will become more critical. To add to the problems, sparsely populated rural areas are becoming prime candidates for location of disposal sites for wastes generated in large metropolitan areas. The need for attention to solid wastes is accentuated by the fact that governments in rural areas are not as well equipped in manpower, expertise, and other resources to deal with solid waste problems as are governmental units for cities and larger metropolitan areas. There is an almost unexplainable void in economic analyses of solid waste disposal. The purpose of this paper is to probe economic issues in solid waste disposal and to suggest problems for analytical research.

— This paper reports the isolation and the identification of ammonia, methylamine, 5-carboxy-l, 3-dimethyluracil, acetic acid, formic acid, 5-formyluracil, and formaldehyde from an aqueous solution of 1,3-dimethylthymine which was irradiated with 254 mμ light resulting in a decrease of 50 per cent of the original ultraviolet absorbancy. The isolation of 5-formyl-l, 3-dimethyluracil as a major photoproduct indicated the possible photo-oxidation of the 5-methyl group of thymine derivatives. The possible presence of an oxidized intermediate in DNA may prove important in radiation biology.

Flow field of impulsively started circular cylinder, noting drag due to nonlinear convection

— The observation of the photo-oxidation of the 5-methyl group of thymine derivatives in aqueous solution led to the suggestion of the formation of dithymine peroxide (TOOT) as the common initial intermediate. The mechanisms for converting TOOT into various oxidation products were discussed. Stereochemically, TOOT can be considered as an outstanding intermediate for the irradiation of DNA. Also, the identification of 5-formyluracil as a photoproduct may provide a chemical explanation for the crosslinking of DNA to protein.

The boundary layer equations, formulated in cylindrical polar coordinates, are applied to a circular cylinder in a slightly viscous stream which is oscillating with a high reduced frequency. The resistance is correctly calculated to the second order. The first order part, 45 ∘ 45^\circ out of phase, is due to the interaction of viscosity with acceleration. The second order part, − 90 ∘ -90^\circ out of phase, is due to the interaction of viscosity with curvature. The interaction of viscosity with inertia, which is of second order also, contributes no resistance.

The transaminase activity of roach muscle homogenate was measured by the spectrophotometric method for oxalacetic acid. The transaminase activity of muscle from allatectomized roaches of both sexes of adults and nymphs was significantly lower than in normal animals. There was also a significant difference between sexes. The reduction in transaminase activity of muscle from female adults was about twice that of male adults but between nymphs the difference due to sex was not nearly so striking. The activity of muscle tissue due to allatectomy was considerably more reduced in male nymphs than in male adults. The significance of these results is discussed.

Nach oraler Zufuhr des oligen Jodadditionspraparates “Jodipin” wird durch die Pankreaslipase wahrend der Darmpassage, fermentativ Jod abgespalten, resorbiert und durch die Nieren ausgeschieden. Dieses eliminierte Jod last sich qualitativ im Harn nachweisen. Erfolgt keine Jod-ausscheidung im Harn, so kann eine fehlende oder unzulangliche Lipaseaktivitat angenommen werden. Mit Hilfe dieser Methode wurden insgesamt 100 Kinder untersucht und zwar 52 eutrophe (Gruppe A), 41 dystrophe (Gruppe B) und 7 an cystischer Pankreasfibrose erkrankte Kinder (Gruppe C). Wahrend alle eutrophen Kinder 4 Std nach der oralen Jodipingabe eine positive Jodprobe im Harn aufwiesen, waren 22% der dystrophen Kinder noch jodnegativ. Insgesamt ergab sich besonders in der Harnverdunnung 1:16 eine (auch statistisch gesicherte) Differenz zwischen den eutrophen und dystrophen Kindern in dem Sinne, das die dystrophen Kinder eine deutlich verzogerte Jodeliminierung aufwiesen. Die Gruppe der an cystischer Pankreasfibrose erkrankten Kinder hatte eine noch wesentlich ausgepragtere Verzogerung oder sogar ganzlich fehlende Ausscheidung von Jod im Harn. Wenn auch dadurch eine sehr eindrucksvolle Differenz zwischen den eutrophen Kindern und denen mit cystischer Pankreasfibrose gefunden worden ist, so sind diese Unterschiede schiede swischen den dystrophen und denen mit cystischer Pankreasfibrose zwar auch nachweisbar, aber die Differenzierung ist hier schwieriger. Unter Berucksichtigung der erorterten Fehlermoglichkeiten ergibt sich aber aus dieser Untersuchung, das der Jodipintest zur Voruntersuchung von Kindern, die auf das Vorliegen einer cystischen Pankreasfibrose verdachtig sind, sicherlich praktisch geeignet ist. Allerdings mus die endgultige Diagnose dieser Erkrankung nach, wie vor von den Ergebnissen der Schweis-Elektrolyt-Bestimmung und der Untersuchung des Duodenalsaftes abhangig gemacht werden.

WHEN 5,6-unsubstituted pyrimidines (I) such as uracil, uridine and 1,3-dimethyluracil are irradiated with ultra-violet light, the absorption spectra gradually decrease with a simultaneous increase in end absorption. These spectra can be reversed to the original by acid, alkali or heat1. However, compounds substituted in the 5-position (II), such as thymine, thymidine and 1,3-dimethyl-thymine, do not show reversal under similar conditions. Most investigators have suggested that this difference may be due to totally different photochemical reaction mechanisms in the two cases2.

The effects of ultraviolet irradiation on 6-hydroxy1,3- dimethylhydrouracil resulted in the formation of N,N' -dimethylmalonamide via 1,3- dimethylbarbituric acid. The irradiation reaction sequence was investigated. The kinetics were studied, and the mechanisms were discussed. (auth)

A class of exact solutions of the Navier-Stokes equations has been generalized. This class of solutions has the property that the non-linear terms of the Navier-Stokes equations are self-canceling such that the resultant equations are linear and solvable. Examples in Cartesian coordinates and their applications are also illustrated.

The first isolated product of the ultraviolet irradiation of 1,3- dimethyluracil was identified by synthesis as 6-hydroxyl-1,3-dimethylhydrouracil. 5-Hydroxy1,3-dimethylhydrouracil was eliminated as a possible intermediate in this process. A mechanism for this process was proposed. (auth)

// Mei Wang 1, * , Yang Liu 2, 3, * , Jiahua Zou 1 , Rui Yang 1 , Fan Xuan 1 , Yi Wang 3 , Ning Gao 4 , Hongjuan Cui 1 1 State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China 2 Department of Respiration, the Third Hospital of Hebei Medical University, Shijiazhuang, China 3 Cardiovascular Department, Second Affiliated Hospital of University of South China, Hengyang, China 4 Department of Pharmacognosy, College of Pharmacy, Third Military Medical University, Chongqing, China * These authors have contributed equally to this work Correspondence to: Hongjuan Cui, e-mail: hongjuan.cui@gmail.com , hcui@swu.edu.cn Ning Gao, e-mail: gaoning59@gmail.com Keywords: TAZ, cell proliferation, colony formation, neuroblastoma Received: Novmember 25, 2014 Accepted: February 11, 2015 Published: March 24, 2015 ABSTRACT Neuroblastoma is a common childhood malignant tumor originated from the neural crest-derived sympathetic nervous system. A crucial event in the pathogenesis of neuroblastoma is to promote proliferation of neuroblasts, which is closely related to poor survival. However, mechanisms for regulation of cell proliferation and tumorigenicity in neuroblastoma are not well understood. Here, we report that overexpression of TAZ in neuroblastoma BE(2)-C cells causes increases in cell proliferation, self renewal and colony formation, which was restored back to its original levels by knockdown of TAZ in TAZ-overexpression cells. Inhibition of endogenous TAZ attenuated cell proliferation, colony formation and tumor development in neuroblastoma SK-N-AS cell, which could be rescued by re-introduction of TAZ into TAZ-knockdown cells. In addition, we found that overexpressing TAZ-mediated induction of CTGF and PDGF-β expression, cell proliferation and colony formation were inhibited by knocking down CTGF and PDGF-β with siRNA in TAZ-overexpressing cell. Overall, our findings suggested that TAZ plays an essential role in regulating cell proliferation and tumorigenesis in neuroblastoma cells. Thus, TAZ seems to be a novel and promising target for the treatment of neuroblastoma.