bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparative evaluation of wound healing potency of Vitex trifolia L. and Vitex altissima L.
Authors: Manjunatha B. K. , Vidya S. M. , Krishna V. , Mankani K. L. , Singh S. D. Jagadeesh , Manohara Y. N. 
Published: February 2007

AbstractThe wound healing potency of ethanol leaf extracts of V. trifolia L. and V. altissima L. was evaluated in excision, incision and dead space wound models. Both plants were found to possess significant wound healing activity which was evidenced by a decrease in the period of epithelialization, an increase in the rate of wound contraction, skin breaking strength, granulation tissue dry weight, hydroxyproline content and breaking strength of granulation tissue. Histopathological study of the granulation tissue also showed an increased collagenation when compared with the control group of animals. Of the two extracts, the ethanol leaf extract of V. trifolia showed maximum wound healing activity compared with the leaf extract of V. altissima. However, on comparison with the control group, both leaf extracts were found to possess significant wound healing potency. Copyright © 2007 John Wiley & Sons, Ltd.
Carbenoxolone and triterpenoids inhibited mucin secretion from airway epithelial cells
Authors: Heo Ho Jin , Kim Cheolsu , Lee Hyun Jae , Kim Young Sik , Kang Sam Sik , Seo Un Kyo , Kim Yun Hee , Park Yang Chun , Seok Jeong Ho , Lee Choong Jae 
Published: February 2007

AbstractThis study investigated whether carbenoxolone, oleanolic acid and ursolic acid affect ATP‐induced mucin secretion from cultured airway epithelial cells. Confluent primary hamster tracheal surface epithelial (HTSE) cells were metabolically radiolabeled using 3H‐glucosamine for 24 h and chased for 30 min in the presence of varying concentrations of each agent to assess the effects on 3H‐mucin secretion. The possible cytotoxicity of each agent was investigated with a lactate dehydrogenase assay. The results were as follows: (1) carbenoxolone, oleanolic acid and ursolic acid significantly inhibited the secretion of airway mucin induced by ATP; (2) none of the compounds showed significant cytotoxicity at any concentration. This result suggests that carbenoxolone, oleanolic acid and ursolic acid can regulate ‘mucin secretion induced by ATP’ – a phenomenon simulating mucus overproduction from inflamed airway epithelial cells – by directly acting on airway mucin‐secreting cells. Copyright © 2007 John Wiley & Sons, Ltd.
Forecasting the coastal rainfall of burma
Authors: Kha Maung Maung 
Published: February 2007

AbstractThis paper describes an attempt to drive forecasting formulae for the mansoon rainfalls during the season, June to August, for the Arakan Coast, the Irrawaddy Delta and the Tenasserim Coast of Burma.The method used is partly synoptic and partly statistical. In the first place, the anomalies (i.e., deviations from long‐period mean values) of monthly pressure and temperature over the world from January to May in the years of extraordinarily deficient and excessive rainfalls are plotted on world maps. These maps are then examined with a view to finding features which are common to years of deficient rainfall and which are reversed in years of excessive rainfall.When such features have been found, the appropriate arithmetical data representing these features are correlated with the rainfalls of the three regions. Sir Gilbert Walker's methods are then employed for evaluating regression equations connecting the rainfall with the factors correlated.Forecasting formulae (regression equations) are developed separately for the Arakan Coast rainfall, the Irrawaddy Delta rainfall and the Tenasserim Coast rainfall. The total theoretical correlation coefficients between the forecast and actual rainfall are .80, .80 and .87 respectively.
Inclined streamline flow
Authors: Schaffer T. W. 
Published: February 2007

AbstractEquations of motion for air‐currents flowing at an angle to the horizontal are derived. From these an equation is developed relating the veering or backing of the wind with height to the rate of ascent of the air and the local rate of rise of temperature. An implication concerning the upper pressure field is briefly investigated and finally some simple illustrative examples are given.
Rainless days of London
Authors: Belasco J. E. 
Published: February 2007

AbstractThe incidence of the 12,616 rainless days which have occurred at London (Kew) during the 70 years, 1878 to 1947, has been examined, a rainless day being one on which less than 0·1 mm. of rain has fallen.The average number of rainless days is greatest in June and least in November. On the average just under half the days in the year are rainless.For the 70 years, the frequency of rainless days on each day of the year has been found, that on May 21 being the greatest, that on October 28 the least. Many of the days when this frequency is exceptionally high or low are associated respectively either with the anticyclonic or stormy “singularities” of C.E.P. Brooks, or with large positive and negatives departures from the mean daily pressure at Kew.The shortest rainless spells (1 and 2 days) are most frequent in October, the longest (exceeding 14 days) in July. Spells of more than 14 days have not been recorded between October 28 and January 22. Spells exceeding 6 days' duration occur at all seasons of the year. They are to be expected most frequently in June and least so just after Christmas. The odds to one against the occurence of a rainless day being included in a rainless spell exceeding 14 days are about 10 in June and July and 118 in January.An examination has been made of the synoptic succession which marks the onset, course and termination of the nine longest rainless spells and a brief summary given.
Heat transport and zonal stress between latitudes
Authors: Priestley C. H. B. 
Published: February 2007

AbstractThe meridional flux of heat, water vapour, and momentum can be directly evaluated at any station where regular radio soundings and upper wind measurements are made. Physically and mathematically it is convenient to separate the flux into an eddy flux, due to the migrant pressure systems, a standing‐eddy flux attributed to the semi‐permanent systems, and a third component arising from the toroidal circulation.The first and third have been evaluated for a two‐year period at Larkhill. Certain earlier conjectures concerning the general circulation and internal heat adjustment of the atmosphere are hereby directly confirmed. The distribution of eddy flux with height and with season are studied. Among the more important new results is that, in this region at least, the eddy‐flow of heat at some levels is from regions of low towards higher mean temperature and that the eddy‐fluxes of heat in sensible and latent form are approximately equal.The horizontal eddy stress is not uniquely determined by the direction of increasing angular momentum, and its sense may vary from season to season.The main purpose of this preliminary work is to draw attention to the method and its potential importance in physical climatology, and to appeal for a global investigation which is beyond the capacity of any one individual.
Vertical diffusion in the lowest layers of the atmosphere
Authors: Deacon E. L. 
Published: February 2007

AbstractA semi‐empirical treatment of the vertical diffusion of matter in the lowest layers of the atmosphere is given in the following and shown to be in good agreement with the results of carefully conducted field experiments made over two different types of natural land surface. The present work extends the treatment of diffusion in an adiabatic atmosphere given by Calder (1948) by allowing for the effects of thermal stratification.The treatment is based on the results of an extensive investigation of vertical profiles of mean wind velocity in the lowest ten metres of the atmosphere (mainly carried out at the Chemical Defence Experimental Station, Porton, Salisbury Plain). A complete account of this study will probably be published as aGeophysical Memoirof the Meteorological Office.
Constant‐Height Balloons – Calculation of Geostrophic Departures
Authors: Durst C. S. , Gilbert G. H. 
Published: February 2007

AbstractThe accelerations observed during the flight of seven constant‐height balloons are examined.These observations extended over periods of 2 to 4 1/2 hr. It is found that the values of the geostrophic departures determined from the accelerations are closely comparable with the values deduced independently from contour charts and observed winds.The variations in the acceleration are greater than would be expected from errors in wind determination alone; it is deduced that this is due to the wind at the level of flight being affected by eddies giving rise to fluctuations of the order of 3 to 4 kt in the value of the mean wind determined over half‐hour intervals.
A study of the transfer of heat and water vapour above a surface of short grass
Authors: Rider N. E. , Robinson G. D. 
Published: February 2007

AbstractThe profiles of temperature, humidity and wind have been determined by conventional methods in the lowest 2 m of the atmosphere above a close‐cut grass surface, with simultaneous observations of the heat absorbed in the soil and of the short‐wave and long‐wave radiative flux of heat. Twentynine sets of observations were made; the details are given in Appendix I.The ratio of the gradients of temperature and humidity is found to be independent of height, and changes with height of the vertical convective flux of heat and of water vapour are relatively small; the ratio of the coefficients of eddy diffusion of heat and water vapour is therefore independent of height. These coefficients are then assumed equal and the convective fluxes of heat and of water vapour determined (Bowen's method). The fluxes are also determined by an aerodynamic method which assumes equality of the eddy viscosity and the appropriate diffusion coefficient. The results of the two methods agree in most cases, in both stable and unstable stratifications, but there are some exceptions which cannot be explained.Absorption of radiation by the air is investigated. It is shown that this is comparable in effect with convection in the control of temperature and relative humidity. Particular attention is paid to four occasions with very light wind (including two with fog formation) when horizontal mixing appeared to be of major importance.Some examples are presented of wind profiles which do not conform to the law proposed by Deacon. A value between 0.5 and 1.5 is suggested for the critical Richardson number.
On the direct measurement of humidity mixing ratio and its fluctuations
Authors: Sheppard P. A. , Elnesr M. K. 
Published: February 2007

AbstractAn apparatus is described for the direct measurement of humidity mixing ratio. It is designed primarily for recording the turbulent fluctuations in the mixing ratio in the lower atmosphere, and is based on an electrical analogue of the wet‐bulb equation, using dry‐ and wet‐bulb thermocouples.Field tests give agreement with Assmann psychrometer values to within less than 1 per cent under favourable conditions for comparison.
Synoptic properties of frontal surfaces
Authors: Godson W. L. 
Published: February 2007

AbstractThe mathematical consequences of a first‐order temperature discontinuity at a front are developed for the fields of pressure, temperature, and geostrophic wind. These results are applied to determine the correct construction of synoptic charts in the vicinity of fronts, and to determine criteria for obtaining the boundary levels of frontal surfaces, as well as their orientations and slopes. Techniques for qualitative and quantitative evaluation of vertical motions at fronts are also presented. These concepts, and analytical methods based on them, are illustrated by reference to the synoptic situation over North America on 4 April 1950. Particular attention is paid to the structure of occluded frontal waves, their three‐dimensional analysis and representation.
The slopes of cumulus clouds in relation to external wind shear
Authors: Malkus Joanne S. 
Published: February 2007

AbstractAn equation for the slope of cumulus clouds is derived. It is shown to depend upon the vertical ascent rate, the external wind shear and the horizontal frictional forces between the cloud and its surroundings. These frictional forces are of two origins: one due to entrainment or mixing with the outside air, and the other due to form or body drag.Four observational cases are presented, one concerning trade cumulus, and three involving clouds in mid‐latitudes. In two of these, measurement of updraught speed, wind shear, and cloud slope permit an estimate of the magnitude of the friction forces. The minimum contribution due to entrainment is approximately equal to that inferred by Stommel for trade cumulus.
Orographic cirrus clouds
Authors: Ludlam F. H. 
Published: February 2007

AbstractObservations are described from which it is inferred that the air flowing over small hills (1,000 ft high) may even in the cirrus levels suffer vertical displacements of 2,000 ft or more, which cause the formation of clouds able to travel away from the hills, and may be responsible for a diurnal variation in cirrus frequency.
The evaluation of infra‐red radiative fluxes due to atmospheric water vapour
Authors: Godson W. L. 
Published: February 2007

AbstractAn empirical technique is developed for obtaining the flux transmission, over a narrow spectral interval, of an assembly of layers of varying pressure and temperature. Although verified only for a regular spectrum of the type proposed by Elsasser (1942), the technique should be valid for any type of spectrum. Using this technique as a check, an empirical method of sufficient accuracy is developed for evaluating the integrated flux transmission of an assembly of layers. This latter method enables the radiation‐chart procedures, advocated by Elsasser (1942), Robinson (1947), and Yamamoto (1952), to be tested for simply‐stratified atmospheric models. Such tests reveal that the effects of temperature are inadequately taken into account. A principle advocated by Cowling (1950b) is developed into a radiation‐chart procedure, in which the absorbing mass of each individual layer is corrected to a standard temperature and pressure. The coordinates of such a radiation chart are presented, but unfortunately adequate experimental data for the construction of such a chart are not yet available.
Turbulence in clouds as a factor in precipitation
Authors: East T. W. R. , Marshall J. S. 
Published: February 2007

AbstractVisual and radar observations of the height of formation of precipitation in shower clouds in relation to temperature, and measurements of droplet population, show that when cumulus clouds produce showers it is often by coalescence, rather than by an ice‐phase process.Langmuir's work gave the conditions necessary for collisions to take place between droplets. The droplets of young cumulus clouds are less than 20 microns in radius and calculation shows that they are too small and settle too slowly by gravity alone to grow at an appreciable rate by colliding with each other.The updraught in a cumulus cloud is highly turbulent so that the air containing the droplets is being perpetually accelerated in a random way. An analysis of random acceleration in one dimension shows that it would produce collisions if violent enough, and in conjunction with gravity would start droplets into growth. Once their radii reached about 20 microns they would continue to grow with or without turbulence. Such a mechanism is consistent with the observed changes in droplet size distribution.Provided that sufficient energy were available in a suitable frequency range, turbulence would initiate a shower in a cumulus cloud. Numerical confirmation of the mechanism awaits suitable measurements of small‐scale turbulence in cloud, but meanwhile an alternative approach through macroscopic energy considerations might prove fruitful.
The terminal velocity of snowflakes
Authors: Langleben M. P. 
Published: February 2007

AbstractMeasurements of the terminal velocity of aggregate snowflakes at the ground indicate that the velocity is approximately proportional to the one‐tenth power of the mass. The constant of proportionality is dependent on the basic crystal types in the aggregates. It is moreover greatly increased by riming or by slight melting of the snowflakes.When snow grows markedly at a generating level, the rate of fall of the snow particles as determined from radar observations is found to correspond to the velocities of aggregates. It is thus inferred that aggregation can occur at temperatures far below the freezing point.
Provisional maps of the reliability of annual rainfall in East Africa
Authors: Glover J. , Robinson P. , Henderson J. P. 
Published: February 2007

AbstractEast Africa is a dry country. Its increasing population, which is dependent on agriculture, seeks expansion into new agricultural lands. Most of the available land lies in regions of low and variable rainfall. One of the most important requirements in the selection of sites for future development is that they should be subject to a reasonably reliable rainfall suited to the potential crop.Earlier investigations have shown that the distribution of annual and seasonal rainfall in East Africa can be assumed to be normal for all practical purposes. On this basis it is possible to calculate the probabilities of receiving certain selected minimum values suited to a crop, and these can be combined for mapping purposes. Maps of the reliability of annual rainfall at two selected levels illustrate the potentialities of the method. The meteorological background to the maps and their application to agricultural development are briefly discussed.
Electrostatic field‐changes due to lightning discharges
Authors: Pierce E. T. 
Published: February 2007

AbstractExtensive observations are described of the changes of electrical field produced by lightning discharges at distances of less than 100 km; in this range electrostatic effects are dominant. The results are analysed in detail.A long series of capillary‐electrometer records obtained with auxiliary amplifying equipment give statistical information upon the magnitude‐distance and sign‐distance relationships for the total electrostatic field‐change due to a lightning flash. From oscillographic observations it is shown that most of this change in field occurs comparatively slowly. It has proved possible to separate field‐changes into distinct groups; these are considered in turn and values given for such quantities as the electric moment and the times involved in each stage, etc.Finally, meteorological influences and the relative frequency of occurrence of cloud and ground discharges are investigated.
A working theory of the bent‐over plume of hot gas
Authors: Priestley C. H. B. 
Published: February 2007

AbstractAn ascending plume of hot gas is initially diffused by the turbulence which is induced by its own motion and later, but before all upward motion and buoyancy are lost, by the natural turbulence of the environment. A working solution is put forward for the first phase in terms of a spreading coefficient c and for the second in terms of a mixing rate k, and it is shown that the transition from one phase to the other should be quite well marked. Proposed laws for c and k as functions of wind speed lead to good agreement with Bosanquet's measurements of plume heights downwind from factory chimneys.The theory extends to conditions of thermal stratification. It shows that a final equilibrium level should always exist except when very light winds coincide with unstable stratification, and it indicates the buoyancy and stratification factors appropriate for scaling down to wind‐tunnel experiments. The relative roles of initial impetus and initial buoyancy are characterized by a modified form of the Froude number.
The empirical relation between solar radiation and hours of bright sunshine in the high‐altitude tropics
Authors: Glover J. , McCulloch J. S. G. 
Published: February 2007

AbstractThe relationship between total solar radiation on a horizontal surface (Q), as measured by a pyranometer, and hours of bright sunshine (n), as measured by a Campbell‐Stokes recorder, has been examined and it is shown that there is little practical gain in weighting the hourly sunshine records by the sine of the apparent solar altitude.In the non‐dimensional equation

values of a and b derived from daily records are shown to vary widely from month to month but their distribution appears to be substantially normal. Actual mean values of a and b, for a five‐year period (1938–1943) at Kabete, Kenya (altitude 6,000 ft) differed slightly but non‐significantly according to the length of period in which the data were grouped, the slope of the equation increasing with increased smoothing.The sum of a and b has been shown to be approximately constant (≃ 0·82) at Kabete, where the optical air mass varies little throughout the year. For checking the consistency of the data from various parts of the world, it is essential to reduce the differing apparent transmission coefficients to standard measure. In practice, a simple correction to optical air‐mass unity has proved adequate for the records available at this station.
Numerical experiments in the integration of the meteorological equations of motion
Authors: Knighting E. , Jones D. E. , Hinds Mavis K. 
Published: February 2007

AbstractIt is usual to use finite‐difference methods in carrying out the time integration of the equations of motion as adapted to the prediction of the large‐scale atmospheric pattern, and this implies a choice of the mesh length and time increment to be used. The effect of changing the size and orientation of the mesh upon the computed values of the vorticities and their advection is examined, and the resulting differences between 24‐hr predictions are shown to be important.
William Bulkeley's record of the weather of Anglesey 1734–1743, 1747–1760
Authors: Oliver J. 
Published: February 2007

AbstractThe study of climatic fluctuations before the nineteenth century is hindered by the paucity and poor distribution of instrumental records, and increasing reliance must be placed upon diaries and other descriptive sources. The diary of William Bulkeley of Anglesey, over the period between 1734 and 1760, has been examined. From the information it contains, resultant wind directions and constancy have been calculated. Frequencies of days with rain, snow, hail, frost and thunder are tabulated. A comparison is made between the general monthly rainfall serial values calculated for England and Wales and data derived from the diary. The record of the aurorae observed is given.
Absorption and emission in the atmospheric window from 770 to 1,250 cm−1
Authors: Roach W. T. , Goody R. M. 
Published: February 2007

AbstractCombined absorption and emission spectra have been recorded in the atmospheric window from 770 to 1,250 cm−1 both in London and in the relatively clean air of Ascot, Berks. The absorption spectra have been partially analysed in terms of selective and continuous extinction. The continuous extinction outweighs the selective in both Ascot and London. There is good agreement between the observed selective absorption and existing theoretical and laboratory data upon gases known to be present in the atmosphere.The opacity of the continuum shows an increase towards low frequency, and it is much greater in London than in Ascot; in both places it is positively correlated with water vapour. The average effective emission temperature of the continuum is not significantly different from that of water vapour.The only hypothesis which seems to fit all the observations is that in London the continuum extinction is largely caused by aerosol extinction while in Ascot this is only of minor importance. This requires that the extinction at Ascot be caused by wings of distant lines; this old suggestion of Elsasser is re‐examined and found to be plausible.Attention is drawn to the important contribution which the continuum can make to the heat balance of the atmosphere below 2 km.