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Turbulence measurements obtained from concurrent tower and aircraft observations are analyzed to test G.I. Taylor's hypothesis (1938) of the equivalence between Eulerian space and Eulerian time spectra. The correlation and spectral data (along with data obtained from three other airplane turbulence programs) were also examined to ascertain the validity of Kolmogoroff's prediction (1940) for the behavior of the correlation coefficients and spectral densities in the inertial subrange. At heights of 300–400 ft above the ground, the tower and aircraft observations provide the same turbulence spectrum for wavelengths at least as large as 600 and 900 ft, for mean wind speeds of about 20 and 30 ft sec−1, respectively. The evidence is that the Kolmogoroff range is not approached for the wavelength range examined in this paper. The shortest wavelength sampled is on the order of 88 ft, at heights above the ground ranging from 200 to 2000 ft. It appears that at these heights, the Kolmogoroff spectrum, if va...

A field of turbulence and space and time wind variability in the lee of a ridge line is observed with double theodolite wind data. It is shown that the most turbulent areas occur above the lee slope and are associated with the sharp transition zone between the wind shadow regime just above the slope and the prevailing flow. This transition zone is quite intermittent in time and variable in height and is usually characterized by sustained vertical gusts which may extend to 3 km downwind of the ridge line. The scale of turbulence in the transition zone is quite large. Examples of pure thermodynamic upslope winds are also given. The effect of insolation and prevailing wind speed on the turbulent regime in the valley is discussed and it is shown that the zone of maximum turbulence and wind unrest tends to move to ridge line height under relatively stable temperature gradient conditions.

A description is given of the experimental techniques employed in a study of urban air pollution in the New York Metropolitan Area. The experimental measurements consist of an anemometer network, an SO2 ground network, an upper level wind network and programmed flight of a helicopter, and fixed winged aircraft equipped to measure pressure height, temperature, wet bulb depression, and SO2 concentration. Some highlights of the observational program are shown. These include detailed pictures of the height distribution of the urban heat island, associated wind flow patterns, and their effect on the distribution of concentration within the city. Some examples are given of the three-dimensional distribution of temperature and SO2 within the urban area. These observations are discussed in the context of a numerical model.

The two dimensional diffusion of a polydispersed cloud in the surface layers of the atmosphere is treated by integrating the monodispersed solution over a distribution of particle sizes. An analytic solution is constructed from consideration of the non-dimensional parameters upon which the value of the integrals depend. It is possible then to construct criteria for neglecting either the dispersion of particle terminal velocity or the diffusive action of turbulent eddies. The criteria are fully worked out for the case of a log normal distribution of mass versus terminal velocity. For this case, the criteria depend only on the logarithm of the ratios of the median terminal velocity to the diffusion velocity, and on the logarithmic standard deviation of the terminal velocity distribution.

SummaryRibosomal S6 kinase 1 (S6K1) is a major mTOR downstream signaling molecule that regulates cell size and translation efficiency. Here, we report that short isoforms of S6K1 are overproduced in breast cancer cell lines and tumors. Overexpression of S6K1 short isoforms induces transformation of human breast epithelial cells. The long S6K1 variant (Iso-1) induced opposite effects. It inhibits Ras-induced transformation and tumor formation, while its knockdown or knockout induces transformation, suggesting that Iso-1 has a tumor-suppressor activity. Furthermore, we found that S6K1 short isoforms bind and activate mTORC1, elevating 4E-BP1 phosphorylation, cap-dependent translation, and Mcl-1 protein levels. Both a phosphorylation-defective 4E-BP1 mutant and the mTORC1 inhibitor rapamycin partially blocked the oncogenic effects of S6K1 short isoforms, suggesting that these are mediated by mTORC1 and 4E-BP1. Thus, alternative splicing of S6K1 acts as a molecular switch in breast cancer cells, elevating oncogenic isoforms that activate mTORC1.

In patients with serous adenocarcinoma (SAC) of the endometrium, we evaluated the prognostic importance of clinicopathological parameters, DNA ploidy, and immunoexpression of p53, estrogen receptor (ER), progesterone receptor (PR), and Ki-67. In a series of 73 stage I and II SAC, DNA ploidy analysis was performed on hysterectomy specimens using DNA image cytometry. Immunohistochemical analysis of p53, ER, PR, and Ki-67 expression was additionally performed. In the review of the histological slides by three gynecologic pathologists, the presence of a serous component was not agreed upon in 17 (23 %) cases. The remaining 56 cases, consisting of pure SAC or SAC mixed with endometrioid adenocarcinoma, were further analyzed. Tumor recurrence was observed in 14 patients, and 28 patients died during the follow-up period. Patients with diploid (n = 19), aneuploid (n = 29), and tetraploid (n = 8) tumor had 5-year recurrence rates of 10, 38, and 53 %, respectively (p = 0.09). A DNA ploidy parameter, 5c exceeding rate, was found to be a prognostic marker for recurrence (p = 0.03), progression-free survival (p

SummaryResistance to chemotherapy represents a major obstacle for long-term remission, and effective strategies to overcome drug resistance would have significant clinical impact. We report that recurrent ovarian carcinomas after paclitaxel/carboplatin treatment have higher levels of spleen tyrosine kinase (SYK) and phospho-SYK. In vitro, paclitaxel-resistant cells expressed higher SYK, and the ratio of phospho-SYK/SYK positively associated with paclitaxel resistance in ovarian cancer cells. Inactivation of SYK by inhibitors or gene knockdown sensitized paclitaxel cytotoxicity in vitro and in vivo. Analysis of the phosphotyrosine proteome in paclitaxel-resistant tumor cells revealed that SYK phosphorylates tubulins and microtubule-associated proteins. Inhibition of SYK enhanced microtubule stability in paclitaxel-resistant tumor cells that were otherwise insensitive. Thus, targeting SYK pathway is a promising strategy to enhance paclitaxel response.

The authors have made an extensive analysis dealing with the determination of parameters in the Deacon profile using wind velocity and temperature data obtained by a research group of the Johns Hopkins University [1953]. The opportunity for making an analysis of the same micrometeorological data presented itself during my stay in Department of Oceanography, the A. & M. College of Texas, and after my return to my present work. The following paragraphs describe the method used in my analysis and some of the results thus obtained.

Low-level wind profiles measured during Project Great Plains were used in the determination of z0, the roughness parameter, and β, the parameter related to profile curvature in Deacon's formula. Anemometers were geometrically spaced at five levels between 40 and 640 cm. The zo values, one for each observation period, found from the four lowest anemometers exceeded the ZQ values found from the four highest anemometers. The p values computed from the highest anemometers departed more from unity than did the p values computed from the lowest set. Since the apparent variability of p with height may be due entirely to the variability of z0, another analysis was conducted with the z0 value fixed for all levels and all hours of an observation period. Although the β variation was reduced by this technique, the departure of β from unity continued to increase with height. Since the Calder-Deacon solutions of equations of diffusion from continuous point and infinite line sources are functions of β and z0 the effects of the height variation of β and z0 on predictions of ground-level concentration were examined. The effects were found to be significant. When for each observation period, β was plotted against a modified form of the Richardson Number, the fitted curves did not coincide. There are indications that during inversion conditions the greatest departures from β = 1 occurred on nights characterized by the presence of a well-defined low-level wind maximum.