bluuebunny/crossref_metadata_2025 huggingface dataset:
Semilobar holoprosencephaly prenatal diagnosis: an unexpected complex rearrangement in a de novo apparently balanced reciprocal translocation on karyotype
Authors: Kanafani S. , Aboura A. , Pipiras E. , Carbillon L. , Tabet A. C. , Largillière C. , Garel C. , Gressens P. , Bucourt M. , Cedrin‐Durnerin I. , Lachassinne E. , Roumegoux C. , Uzan M. , Hugues J. N. , Wolf J. P. , Benzacken B.
Published: February 2007

We report a semilobar holoprosencephaly (HPE) in a post‐intracytoplasmic‐sperm‐injection pregnancy. It was suggested by ultrasonography (US), documented on karyotype, identified with magnetic resonance imaging (MRI), established after birth and confirmed on post‐mortem autopsy. An amniocentesis revealed a de novo apparently balanced reciprocal translocation 46,XY, t(7;8) (q31.3;q12). Fluorescence in situ hybridization (FISH) identified a deletion in the region of the Sonic Hedgehog gene (SHH) on der(8); nevertheless, the subtelomeric regions for chromosomes 7 and 8 were present. The parents decided to continue the pregnancy; a boy was born and survived for 3 days. The brain autopsy confirmed the semilobar HPE previously noted on US and MRI. Further, band‐specific FISH revealed, in addition to SHH deletion, the presence of an inversion in the 7q translocated material on der(8). The parents' karyotypes were normal. An unexpected complex rearrangement was present in a de novo apparently balanced reciprocal translocation in a semilobar HPE. Copyright © 2007 John Wiley & Sons, Ltd.
Maternal serum free‐β‐chorionic gonadotrophin, pregnancy‐associated plasma protein‐A and fetal nuchal translucency thickness at 10–13+6 weeks in relation to co‐variables in pregnant Saudi women
Authors: Ardawi Mohammed‐Salleh M. , Nasrat Hasan A. , Rouzi Abdulrahim A. , Qari Mohammed H. , Al‐Qahtani Mohammed H. , Abuzenadah Adel M.
Published: February 2007

Objective

To establish normative values and distribution parameters of first‐trimester screening markers, namely, fetal nuchal translucency (NT), maternal serum free β‐human chorionic gonadotrophin (β‐hCG) and pregnancy‐associated plasma protein‐A (PAPP‐A), at 10 to 13+6 weeks of gestation in Saudi women and to evaluate the effect of co‐variables including maternal body weight, gravidity, parity, fetal gender, twin pregnancy, smoking and ethnicity on these markers.

Methods

A cohort of Saudi women (first cohort n = 1616) with singleton pregnancies prospectively participated in the present study, and fetal NT together with maternal serum free β‐hCG and PAPP‐A were determined at 10 to 13+6 weeks of gestation. The distribution of gestational age‐independent multiples of the median (MoM) of the parameters was defined and normative values were established, and correction for maternal body weight was made accordingly. The influence of various co‐variables was examined using the data collected from the first and the second (n = 1849) cohorts of women and 62 twin pregnancies, and compared with other studies.

Results

All markers exhibited log‐normally distributed MoMs. Gestational age‐independent normative values were established. Maternal body weight was corrected, particularly for maternal free β‐hCG and PAPP‐A using standard methods. Fetal NT showed a negative relationship with increasing gravidity (r = −0.296) or parity (r = −0.311), whereas both free β‐hCG and PAPP‐A exhibited a significant positive relationship. There was a significant increase in the MoM of free β‐hCG in female fetuses. Smoking decreased MoM values of free β‐hCG (by 14.6%; P < 0.01) and PAPP‐A (by 18.8%; P < 0.001). Twin pregnancy showed significant increases in MoM values of free β‐hCG (by 1.87‐fold) and PAPP‐A (by 2.24‐fold), with no significant changes in fetal NT MoM values. Fetal NT MoM values were lower in Africans and Asians but higher in Orientals, as compared to Saudi women (P < 0.05; in each case). MoM values (body weight‐corrected) of free β‐hCG were 25.2% higher in Africans and 19.4% higher in Orientals but 6.8% lower in other Arabian and Asian (by 5.8%) women as compared to Saudi women (P < 0.05; in each case).

Conclusions

The normative values and distribution parameters for fetal NT, maternal serum free β‐hCG and PAPP‐A were established in Saudi singleton pregnancies, the maternal body weight together with smoking, twin pregnancy and ethnicity being important first‐trimester screening co‐variables. Gravidity, parity and fetal gender are also considered to influence one or more of the first‐trimester markers examined. Copyright © 2007 John Wiley & Sons, Ltd.
Identification of leptomeningeal metastasis‐related proteins in cerebrospinal fluid of patients with breast cancer by a combination of MALDI‐TOF, MALDI‐FTICR and nanoLC‐FTICR MS
Authors: Römpp Andreas , Dekker Lennard , Taban Ioana , Jenster Guido , Boogerd Willem , Bonfrer Hans , Spengler Bernhard , Heeren Ron , Smitt Peter Sillevis , Luider Theo M.
Published: February 2007

Leptomeningeal metastasis (LM) is a devastating complication occurring in 5% of breast cancer patients. However, the current ‘gold standard’ of diagnosis, namely microscopic examination of the cerebrospinal fluid (CSF), is false‐negative in 25% of patients at the first lumbar puncture. In a previous study, we analyzed a set of 151 CSF samples (tryptic digests) by MALDI‐TOF and detected peptide masses that were differentially expressed in breast cancer patients with LM. In the present study, we obtain for a limited number of samples exact masses for these peptides by MALDI‐FTICR MS measurements. Identification of these peptides was performed by electrospray FTICR MS after separation by nano‐scale LC. The database results were confirmed by targeted high mass accuracy measurements of the fragment ions in the FTICR cell. The combination of automated high‐throughput MALDI‐TOF measurements and analysis by FTICR MS leads to the identification of 17 peptides corresponding to 9 proteins. These include proteins that are operative in host‐disease interaction, inflammation and immune defense (serotransferrin, alpha 1‐antichymotrypsin, hemopexin, haptoglobin and transthyretin). Several of these proteins have been mentioned in the literature in relation to cancer. The identified proteins alpha1‐antichymotrypsin and apolipoprotein E have been described in relation to Alzheimer's disease and brain cancer.
From Genome to Proteome: Back to the Future Report on the 7th Siena meeting, September 3–7, 2006
Authors: Pennington Kyla , Pedersen Kasper J. , McManus Ciara A.
Published: February 2007

This report reviews the 7th Siena Meeting ‘From Genome to Proteome: Back to the Future’ which took place in Italy from 3–7 September, 2006. There was a significant rise in the number of delegates attending compared with previous Siena meetings. A diversity of speakers and presentations addressed the theme of the meeting in moving proteomics forward to integrate with biology as a whole entity rather than in isolated fractions. In addition, technological advancements in sample preparation and separation as well as identification were discussed.
Lyotropic liquid‐crystalline behavior of polyisocyanodipeptides
Authors: Metselaar Gerald A. , Wezenberg Sander J. , Cornelissen Jeroen J. L. M. , Nolte Roeland J. M. , Rowan Alan E.
Published: February 2007

Rigid, helical polyisocyanodipeptides derived from alanine (PIAAs) that form lyotropic liquid‐crystalline (LC) phases in tetrachloroethane are presented. An investigation by optical microscopy between crossed polarizers demonstrated that PIAAs prepared by the polymerization of isocyanodipeptide monomers with an activated tetrakis isocyanide nickel(II) catalyst could form cholesteric LC phases in tetrachloroethane in concentrations between 18 and 30 wt %. Cholesteric LC phases that were formed in solutions of greater than 25 wt % displayed a reversal of the cholesteric helix upon annealing at 50 °C. Diastereomeric PIAA mixtures displayed cholesteric LC behavior only when the PIAAs had the same helix screw sense. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 981–988, 2007
Magneto‐subbands in spin–orbit coupled quantum wires with anisotropic 2‐D harmonic potential
Authors: Jeong In‐Taek , Sung Min‐Gyu , Jeon Gun Sang , Yoo Keon‐Ho , Woo Jong‐Chun
Published: February 2007

The spin states of electrons in a perpendicular magnetic field (B) are studied with the introduction of anisotropic harmonic confinement and spin–orbit coupling (SOC) (both Dresselhaus and Rashba interactions). The effective g ‐factors, as well as B ‐dependence of subbands, are numerically calculated for GaAs and their dependence on confinement strength and degree of anisotropy is estimated. This model is in good agreement with previous reports [PRB 72, 155410 (2005) and so on] in the isotropic limit and weak SOC, indicating its usefulness for slightly deformed quantum dots and short quantum wire. However, dispersion caused by mixing of spin states imposes limitations when SOC and confinement are comparable. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Domain‐wall contribution to magnetoresistance of a ferromagnetic (Ga,Mn)As layer
Authors: Wosiński T. , Figielski T. , Pelya O. , Mąkosa A. , Morawski A. , Sadowski J. , Dobrowolski W. , Szymczak R. , Wróbel J.
Published: February 2007

Low‐temperature charge‐carrier transport in simple magnetoresistive nanodevices, consisted of narrow constrictions of submicron width in the epitaxial layer of a ferromagnetic (Ga,Mn)As semiconductor, has been investigated and correlated with magnetic properties of the layer. The devices containing constrictions revealed abrupt jumps of a reduced resistance that appeared when the sweeping magnetic field crossed the regions of the coercive field of the layer magnetization. In contrast, the non‐constricted reference device displayed abrupt jumps of an enhanced resistance at the same values of magnetic field. We interpret the both features, whose positions on the magnetic‐field scale reflect the hysteresis loop of magnetization, as manifestation of domain wall contribution to the (Ga,Mn)As layer resistance. The negative contribution of a domain wall to the resistance in the constricted device results most likely from the suppression of the weak localization effects by a domain wall located at the constriction. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Transport properties of the orbital Kondo effect via quantum dot systems with plural electrons
Authors: Sakano R. , Kita T. , Ohashi T. , Suga S. , Kawakami N.
Published: February 2007

We study transport properties of the orbital Kondo effect via single quantum dot systems with plural electrons by applying the noncrossing approximation to the Anderson impurity model with orbitals. Investigating the case for the half filling of the quantum dot with three orbitals, we discuss the effects of the orbital level splitting on the conductance and the thermopower. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthesis of carbon nanotubes and nanofibers by decomposition of acetylene over a SMAD palladium catalyst
Authors: Segura Rodrigo , Tello Alejandra , Cardenas Galo , Häberle Patricio
Published: February 2007

Filament‐like Carbon Nanostructures were synthesized by decomposition of acetylene over an alumina supported palladium catalyst prepared by the SMAD method. The structure of carbon products was analyzed by transmission electron microscopy. Between 500 and 700 °C the predominant structures were carbon nanofibers. Between 750 and 800 °C an important mass and volume increase of carbon products was observed. For this temperature range most of the Carbon was in the form of high quality multiwall carbon nanotubes. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thermal properties of high power laser bars investigated by spatially resolved thermoreflectance spectroscopy
Authors: Pierścińska D. , Pierściński K. , Bugajski M. , Tomm J. W.
Published: February 2007

We present results of an analysis of the thermal properties of high‐power laser bars obtained by spatially resolved thermoreflectance (TR) spectroscopy. The study of facet heating in high power laser bars is presented. The TR spectroscopy allowed for insight into degradation processes of emitters as well as the heat management of the devices.

Thermoreflectance is a modulation technique relying on periodic temperature modulation induced by pulsed current supply of the device. Information obtained in these experiments provide insight into thermal processes occurring at device facets and potentially leads to increased reliability and substantially longer lifetimes of such structures. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Wen‐pi‐tang‐Hab‐Wu‐ling‐san, an oriental herbal prescription, attenuates epithelial‐mesenchymal transdifferentiation stimulated by TGF‐β1 in kidney cells
Authors: Lee Sang Il , Kim Hyo Jung , Baek Moon‐Chang , Park Kwon Moo , Park Yongki , Yoon Cheol Ho , Boo Yong Chool
Published: February 2007

Wen‐pi‐tang‐Hab‐Wu‐ling‐san (WHW), an oriental herbal prescription, is currently used in oriental clinics for the treatment of chronic renal failure (CRF). While its effectiveness has been supported by a series of modern studies, the underlying mechanism remains poorly understood. CRF progression involves tubulointerstitial fibrosis where transforming growth factor‐β1 (TGF‐β1) plays a critical role by inducing epithelial‐mesenchymal transdifferentiation (EMT). This study examined whether WHW extract attenuated the TGF‐β1‐induced EMT in Madin‐Darby canine kidney cells. When the cells were stimulated by TGF‐β1 (2.5 ng/mL), they exhibited an elongated, spindle‐shaped appearance but this morphological change was significantly suppressed by WHW extract (1 mg/mL). The WHW extract did not show notable cytotoxicity and even mitigated the cytotoxic effects of TGF‐β1. It inhibited the expression of α‐smooth muscle actin (α‐SMA), a marker of EMT, but not the secretion of matrix metalloproteinases stimulated by TGF‐β1. The WHW extract also inhibited the phosphorylation of Smad2 that mediates TGF‐β1 signaling leading to α‐SMA expression. The present study suggests that WHW extract may provide renal protective effects through modulation of the TGF‐β1/Smad2/α‐SMA pathway involved in fibrosis. Copyright © 2007 John Wiley & Sons, Ltd.
The rainfall of the Wrexham district
Authors: Ashmore S. E.
Published: February 2007

The space‐distribution of the rainfall of the Wrexham district, referred to the period 1880‐1942 is given in a map. The distribution in time is analysed under the following divisions:–‐Calendar years, seasonal years, months, seasons, dry and wet spells, and days, and the rainfall régime of the district is discussed. A few of the results are given here.

The climate is of the rain‐shadow type; the incidence of the equinoctial oscillation resembles that of the West Wales stations; the modifying 6‐monthly oscillation is akin to that of dry places such as Rhyl.

The second half of the period under consideration was far wetter than the first half, but it appears that drier conditions may now be re‐commencing.

January has recently tended to become a relatively wetter month.

June provides a notably low percentage of the year's rainfall.

The probability of very excessive annual rainfalls is smaller on the high ground than at low levels.

Skewness is absent from the distribution of 3‐yearly totals at both high and low altitudes.

There is more than the normal tendency for the persistence of both dry and wet sequences of months, when they have lasted six months.

The probable maximum duration of a partial drought is 55 days, and of a rain spell, 38 days.

The mean rainfall per rain‐day is lower than for the British Isles as a whole.

The driest six months give about 30 per cent of the average annual total; the wettest three months about 40 per cent, and the wettest four about 50 per cent.

On the average, the wettest 30 days give half the year's total. The relation between the wetfest n days of the year and the percentage P of the average annual fall is

Jameson's law R=QtK, where R is the mean maximum rain falling in t days holds up to 10 days.

Bilham's law F=ae−bR, where F is the frequency of daily falls with a lower limit R, also holds.
Sequences of wet and dry months and the theory of probability
Authors: Beer Arthur , Drummond A. J. , Fürth R.
Published: February 2007

Serial values of monthly rainfall over long periods at Kew and six other stations in the British Isles have been analysed. The means for each of the twelve months were formed and the sequences of wet and dry months (above and below average respectively) investigated. It was found that a close relationship existed between m, the number of successive like months, and F, the frequency with which such a series occurred; namely log F=Rm+S, where R and S are constants for each station.

In Section III, after statistical tests for the absence of correlation, a mathematical theory has been advanced on the basis that the sequences are purely accidental. The probability formulae obtained explained fully the empirical relationship, giving a satisfactory representation of the observational data.
Forecasting the summer weather of the sudan and the rains that lead to the nile floods
Authors: El‐Fandy M. G
Published: February 2007

In the Sudan, pressure‐distribution shows a characteristic seasonal variation. In summer (mainly June to August) a trough of low pressure (of the belt of the thermal equator) covers the Northern Sudan. An oscillatory barometric minimum is located over the NE. Sudan and is normally an area of almost cloudless skies and intense insolation; while over the greater part of Abyssinia and the SE. Sudan extends a barometric maximum (of the Indian Ocean anticyclone) which also suffers fluctuations in its strength and northward extent. “Haboobs” and local convectional rain over the Sudan usually accompany the northward oscillations of this barometric maximum. It is in tracing such oscillations of the main pressure systems that pressure becomes of some value in forecasting weather in these low latitudes.

The present paper is devoted to a study of the disturbances in the average pressure distribution and the variations in the general wind circulation which are associated with the day‐to‐day outstanding changes of the weather of the Sudan. Four different types of summer disturbance have been distinguished as follows:—

(1) Sand‐storms, or “haboobs”, with a modification of the general circulation by the onset of strong S. winds. These storms are common over the desert areas of the central and northern Sudan. Marked strengthening (and deepening) of the S. to SW. monsoon usually accompanies the northward extension of the barometric maximum of the SE. Sudan together with a northward oscillation of the intertropical convergence zone (I.C.Z.). The origin of this modification of the general circulation appears to lie in a pressure surge which first shows itself by a rise of pressure and fall of temperature in the S. Sudan‐Uganda area and spreads northwards rapidly.

(2) Dust‐storms, or “haboobs”, with “induced cold fronts”, or line squalls set up by thunderstorms.

(3) Low‐level (or local instability) thunderstorms, which form, under favourable conditions of temperature and humidity, by direct convection within the S. to SW. monsoon. These generally occur when the I.C.Z. is at its farthest north, the depth of the monsoon current being then greatest and there is marked increase of moisture content within the lowest layers.

(4) High‐level (or widespread) thunderstorms followed by fairly widespread outbreaks of rain. The term “wide‐spread rain” has been proposed to describe the rainfalls which cover a wide area and may persist for about 24 hours in places.
A note on the eddy transport of angular momentum
Authors: Starr Victor P. , Sheppard P. A.
Published: February 2007

A pilot study of the horizontal eddy transport of angular momentum in the meridional direction, based on radio wind observations over the North American sector of the northern hemisphere, is presented. The results are in harmony with general frictional requirements except that the transports are rather large. The desirability of much more extensive compilations of data concerning the subject is indicated.
The vertical convective heat flux in the atmosphere—a critical essay
Authors: Robinson G. D.
Published: February 2007

A definition of convective vertical heat flux is proposed which leads directly to the expression p1 w1 h1 where p1, w1, and h1 are, respectively, simultaneous values of the fluctuating density, vertical velocity relative to the surface, and total heat per unit mass at a point in a constant pressure surface. Neglect (apparently justifiable) of the pressure fluctuations yields the expression cpp±w1/R for the convective flux of sensible heat. The distinction between free and forced convection is made. Recent treatments by Montgomery and by Priestley and Swinbank are examined with particular attention to the importance of free convection. It is submitted that neither Montgomery's neglect of the buoyancy forces nor Priestley and Swinbank's arguments suggesting their universal importance can at present be justified. In particular the latter authors explanation of the normal tropospheric lapse rate is questioned.
On the stability of stably stratified shearing layers
Authors: Scorer R. S.
Published: February 2007

The equation governing the behaviour of two‐dimensional waves in a horizontal stably stratified shearing air current is set up. It is shown that it may be obtained by considering the limit as the number of a set of superposed statically‐neutral layers, each of constant stream velocity, tends to infinity, but that the properties may differ considerably if the number of layers is few.

If stable waves occur then at no level do they travel with the same velocity as the air. If unstable waves occur the surfaces containing the wave crests may be so inclined to the vertical as to limit the growth of the waves. Some remarks are made concerning the difficulties of discussion of unstable waves in the general case.
The electric charges and masses of single raindrops
Authors: Hutchinson W. C. A. , Chalmers J. Alan
Published: February 2007

Raindrops were admitted by a cone‐shaped opening into an insulated vessel connected to a valve amplifier for measuring the drop charge Q. Drop radius a was found by the absorbent paper method. The field at the ground and the point discharge current I were also measured. Most often, but not always, the signs of the drop charge and field were opposite. During point discharge, 173 drop charges and masses were measured, and statistical analysis showed a definite correlation between Q and I—, a probable correlation between Q/—I and a and a possible correlation between a and —Q. By grouping drops according to radius, and taking averages within the groups, the approximate relationship Q/—I ∞ a was obtained. In one period when the radius was nearly constant, the observations gave the connection Q ∞ — I without taking averages. The observed relation between Q and I corresponds to the results of Simpson (1949) for the charge on a volume of rain. The observed charges were mostly much higher than predicted on Wilson's ion‐capture theory, unless the field increases considerably with height in the atmosphere.
The diurnal march of vapour pressure on sea‐breeze days at Athens, Greece
Authors: Karapiperis Ph.
Published: February 2007

This study is restricted to days with even pressure distribution, and without strong winds that would interfere with the sea breeze. The greatest frequency of such a sea breeze occurs in May, June and October, which are the months of low frequency of the Etesians.

The diurnal march of vapour pressure at Athens is clearly double in all months and the year as a whole. However, on days with uninterrupted sea breeze, mainly from May to October, three pairs of extremes characterize the variation, there being two secondary maxima and two secondary minima in the forenoon. The arrival of the moist sea breeze overcompensates the normal decrease of vapour pressure in the morning.
Sequences of wet and of dry days considered in relation to the logarithmic series
Authors: Williams C. B.
Published: February 2007

It is shown that the frequency distribution of sequences of fine days conforms very closely to a ‘logarithmic’ series. The sequences of ‘wet’ days do not conform so closely, as there is a shortage of one‐day sequences and an excess of 2 to 4‐day sequences, but this may be due to the method of defining ‘wet’ sequences.
Further computations of 24‐hr pressure changes based on a two‐parameter model
Authors: Bushby F. H. , Hinds Mavis K.
Published: February 2007

The results of 13 computed 24‐hr forecasts, using the Sawyer‐Bushby (1953) two‐parameter model atmosphere, are discussed, and further computations to investigate the apparent limitations of the model are described. The effects of the neglect of heating of the atmosphere over the sea, of the use of incorrect boundary conditions and of the use of 500‐mb rather than 600‐mb data are investigated. It is concluded that the imposition of artificial boundary conditions can cause considerable errors, although these will not be serious in the region of the British Isles, and that the effects of non‐adiabatic heating of the air over the sea should be included in the computations.
Geostrophic and ageostrophic wind analysis
Authors: Smith F. B.
Published: February 2007

Aerological data for the British Isles, 1953, at nine pressure levels, are analysed, to give the geostrophic and ageostrophic components of the wind and the radius of curvature of the isobars. The mean total energy over unit surface area is found to be 1·71 × 109 erg cm−2.

The equation of energy associated with the ageostrophic component is obtained, and the work done by the flow down the pressure gradient is identified by means of this equation with a Coriolis term and a centrifugal term. These are estimated from the data, giving a value for the rate of generation of kinetic energy of 8·8 × 103 erg cm−2 sec−1. The mean net mass‐flux across unit length of isobar is found to be 25 kg cm−1 sec−1. The order of magnitude of this quantity is checked in the final section in which a mathematical analysis is applied to a model depression filling by the influx of mass across its perimeter.
The influence of the 9.6 micron ozone band on the atmospheric infra‐red cooling rate
Authors: Plass G. N.
Published: February 2007

The upward and downward radiation flux and the heating and cooling rate in the atmosphere have been determined for the 9.6 μ band of ozone from the absorption measurements of Summerfield. Three different ozone distribution curves as well as three different temperature‐height curves have been used for these calculations. The radiations that interact with the 9.6 μ ozone band always act to cool the atmosphere from the earth's surface to a height of several kilometres and to heat the region from there to approximately 20 km. The heating or cooling rate is never larger than a few tenths of a degree Celsius per day in this region. On the other hand, from 35 to 60 km the usual order of magnitude of the cooling is 2 to 3°C/day, but the cooling rate can be considerably larger if the upper layers have a higher temperature than normal. An increase in the ozone amount at the lower altitudes may cause the surface temperature of the earth to rise several degrees Celsius in order to restore infra‐red equilibrium, if no other factors change that produce an effect upon the heat balance. The pressure broadening and overlapping of the spectral lines have been taken into account in these calculations together with all other physical phenomena that are known to be of importance to the problem. An estimate is given for the accuracy of the results.
Local temperature variations in the Reading area
Authors: Parry M.
Published: February 2007

The following paper describes some results of an investigation of local climate — based on a close network of meteorological stations — undertaken over an 18‐month period in the Reading area. Mean and extreme temperatures, and temperature distributions on selected occasions are examined in relation to the local factors involved: these are mainly the relief and the presence of the town. In particular, the relation between weather conditions and variations in minimum temperatures is considered. Diurnal temperature variations at different sites are compared. Although the local relief is slight and the urban area neither closely built up nor heavily polluted, temperature differences of up to 8°F can occur, and differences in minima of 4°–5° are common, during radiation nights. Maximum temperatures vary little.
Variation of temperature in the troposphere and lower stratosphere
Authors: Bannon J. K. , Gilchrist A.
Published: February 2007

Correlation coefficients are evaluated between temperatures at 500 mb and at three levels in the lower stratosphere (highest 60 mb) and, respectively, the pressure at the tropopause and the height of the 300‐mb level for Larkhill and Lerwick for each month of the year. Similar coefficients are also given for Malta and (for different levels) for Arctic Bay for January, April, July and October. The Dines type of relationship is confirmed for those regions and seasons affected by travelling depressions and anticyclones. There is no significant correlation between similar parameters for Aden and tropical islands in the Pacific. The relation between temperature in the lower stratosphere and, respectively, the level of the tropopause and the height of the 300‐mb level decreases by a factor of 2 or more between the levels of 150 mb and 60 mb at Larkhill, Lerwick and Malta, indicating a marked decrease with height in the effect of tropospheric disturbances on stratospheric temperatures. The stratospheric correlation coefficients for Larkhill and Lerwick have a significant minimum in the winter.
The study of air pollution with the electron microscope
Authors: Cartwright J. , Nagelschmidt G. , Skidmore J. W.
Published: February 2007

The use of electron microscopy for observation and measurement of solid particles in air pollution is described, the thermal precipitator being used as sampling instrument. By using heat‐stable membranes, it is possible to distinguish combustible from non‐combustible matter, and other chemical tests can be used to distinguish different materials.

The shape of the particles in air pollution is mainly spherical; the size varies from 0.01 to 1 μ, although occasional larger particles are found. Many of the spheres are aggregated and resemble carbon black.

Examples are given of quantitative evaluation in terms of weight per unit volume for different size classes. The few results obtained so far show reasonable agreement with previous mass estimates based on smoke‐filter sampling. The future developments in the use of the electron microscope for studying air pollution are briefly discussed.
The use of a stream function in a two‐parameter model of the atmosphere
Authors: Bushby F. H. , Huckle Vera M.
Published: February 2007

In an attempt to obtain a better approximation to the horizontal flow of a non‐divergent fluid than the geostrophic approximation, a Monge‐Ampère type of partial differential equation, similar to that of Charney (1955), is derived to enable a stream function to be found from the contour height field. A method is given for the numerical solution of this equation.

The stream function has been used in place of the contour height parameter to represent the flow at the mean level in computing three 24 hr forecasts based on the Sawyer‐Bushby two‐parameter model of the atmosphere, and the results are compared with similar computations without the stream function.

In one situation, the use of the stream function produced a marked improvement in the computation.
Space and time variations of charged nuclei and electrical conductivity of the atmosphere
Authors: Sagalyn Rita C. , Faucher G. A.
Published: February 2007

The time variations of electrical conductivity and charged nucleus concentration have been investigated in fair weather in the altitude range 700 to 15,000 ft above the surface. In the exchange layer regular variations of nucleus concentration with time are observed from around sunrise to early afternoon. Analysis of the meteorological data obtained simultaneously shows that this variation is due primarily to the daily turbulent cycle. During periods of low advection, regular variations of nucleus concentration with time from early afternoon to the following sunrise are also observed in this region, and are shown to be the result of nucleus coagulation and subsidence. The time variations at night are more complicated during periods of intense advection. Above the exchange layer variations in nucleus content with time are not found to be regular. The variations in electrical conductivity with time are the inverse of the changes in nucleus concentration. The observed relation between conductivity and nucleus concentration is in good agreement with the theory of small ion balance, using Thomson's theory for small ion volume recombination and Bricard's theory for collisions between small ions and nuclei. An analysis of observed daily variations in the magnitude of the horizontal fluctuations of these variables is also given.
A contribution to absolute pyrheliometry
Authors: Drummond A. J.
Published: February 2007

The results are presented of comparisons made in Southern Africa, during the years 1951–1954, between pyrheliometers of the Ångström type which had been standardized at Davos (Switzerland), Leopoldville (Belgian Congo), Pretoria (South Africa) and Stockholm (Sweden). A section is also devoted to an investigation into the relationship between the original Ångström scale and the embodied in the Abbot pattern of actinometer of the Smithsonian Institution, Washington. This latter series of comparisons was made at Pretoria (altitude 1370 m), under normal conditions of cloudless sky with reasonably steayd atmospheric transmission.

The programme was extended to include a comparison between specimens of these two sub‐standard radiometers using a controlled laboratory source of radiation. In these conditions, the radiometers were found to agree to within one‐half per cent. This is further evidence of the small divergence (first pointed out by Guild in 1937) of the scale originated long ago by Knut Ångström, from the true standard of radiometry.
The melting point of diphenyl ether as a self‐maintaining reference temperature in an equatorial climate
Authors: Webb C. G.
Published: February 2007

It is possible, and convenient, in an equatorial climate to use the melting point of diphenyl ether (26.6°C) as a thermocouple reference temperature which, under specified conditions, will be self‐maintaining in the open air to within ± 0.1°C for periods of about a fortnight, the ambient temperature range being ± 5°C.
The use of balloons in atmospheric pollution research
Authors: Lucas D. H. , Spurr G. , Williams F.
Published: February 2007

An experimental technique has been established for measuring the rise of a plume from a stack, the ground‐level concentrations produced and the rates of deposition of dust emitted in the plume. It can be applied over distances where plumes from power stations are not normally visible. It can be used to give a result before weather and station conditions have changed appreciably and therefore produces information which can conveniently be compared with theoretical estimates.
Patterns of hailstorms in Alberta
Authors: Douglas R. H. , Hitschfeld W.
Published: February 2007

Between 14 June and 20 September 1957, nearly 3,200 surface reports of hail were collected in a 15,000 sq. mile area. Information included location, time and duration of hail and the largest size of hail encountered. Continuous radar records of the storm pattern were taken in a manner suitable for the preparation of constant‐altitude radar weather (CAPI) maps, to a range of 100 miles.

At times, hail fell soon after a first echo (possibly within 10 min), sometimes no hail occurred for as long as an hour or two. Usually, the hail fell in short bursts (lasting up to 20 min and spread over a few miles) which would appear to be the products of single storm cells. But on several occasions (notably on 23 July) hail fell continuously for 11/2 hours and, without evidence of a multiplicity of cells, covered a strip 30 mi long. Sustained hail came from storms whose echo tops were steady close to 30 kft above surface. Hail associated with echoes of lesser height was not continuous and tended to fall in bursts which sometimes followed closely on the merger of previously separate storms. A study of 83 independent echoes showed that the probability of hail from a given storm was clearly related to maximum height of the storm, rising from zero for storms 10 kft or lower, to 100 per cent for storms 38 kft or more in height. A similar correlation holds between echo height of a hailstorm at any instant and hail arrival at the ground some minutes later.
Some observations of potential evaporation, 1955–1957
Authors: Green F. H. W.
Published: February 2007

The methods of interpreting routine observations with an apparatus designed to measure potential evaporation (PE) are discussed, and tables of results are presented. With a view to standardizing PE measurements, conditions are defined, resembling those for standard climatological stations. Difficulties in the interpretation of daily observations, because of various kinds of time‐lag, and variations in storage of water in the apparatus, have been encountered but largely overcome. The values obtained are compared with those computed from other available data by the methods of Penman, Thornthwaite, and Crowe, in which the conditions are either specified, or tacitly assumed, to be similar. The values are in general agreement, but it is shown that at west coast stations in Britain the observed values tend to be lower than the computed, and, more strikingly, that at high‐altitude stations, they tend to be higher.
The pressure gradient at the edge of an Ice Sheet
Authors: Hamilton R. A.
Published: February 2007

Mean sea‐level pressures on the NE coast of Greenland are compared with those of a low‐level station within the edge of the inland ice. The comparison indicates that there is no evidence of an unusually high pressure gradient near the ice edge.
Research on methods of forecasting storm surges on the east and south coasts of Great Britain
Authors: Rossiter J. R.
Published: February 2007

Recent work at the Tidal Institute has provided means of predicting storm surges at the River Tyne entrance, Immingham, King's Lynn, Lowestoft and Southend in the North Sea and Newhaven in the English Channel, from meteorological forecasts.

An investigation of surges at Aberdeen has not resulted in a completely satisfactory method of predicting external surges, which are generated outside the North Sea, so that their effects at ports further south have been allowed for by observing their magnitude at Aberdeen and applying an empirical rule which governs their amplification and rate of travel, after Corkan (1948). The disturbances generated inside the North Sea proper, at all the other North Sea ports except King's Lynn, have been correlated at intervals of 6 hr with quantities representing the tractive force of the gradient winds at chosen points in the sea, assuming a quadratic law of friction. The success of the formulae so produced is fully illustrated. For King's Lynn, tide and surge have been treated as an entity, and high‐ and low‐water heights have been expressed as functions of the corresponding heights at the River Tyne and the local wind strength and direction.

The propagation of North Sea surges through the Straits of Dover has been studied using Newhaven observations, and it is shown that they travel from Lowestoft as free progressive waves, being attenuated by half. Depressions in the western approaches to the English Channel are also shown to be responsible for disturbances at Newhaven.
A method of determining the constant in the balloon‐ascent formula
Authors: Sinha K. L.
Published: February 2007

Expressing the coefficient q, of the rate‐of‐ascent formula of the balloon (e.g. V = q F1/2/(W + F)1/3, where V is the rate of ascent of the balloon, W the weight of the balloon and F the free‐lift) in terms of the coefficient of aerodynamic resistance κ of the balloon, a curve of q as a function of the Reynolds number N is worked out. Introducing a κN2 – N curve, the value of q, appropriate to a balloon flight is obtained.
Numerical calculation of the displacements of a stratified airstream crossing a ridge of small height
Authors: Sawyer J. S.
Published: February 2007

Numerical computations have been made of the solutions of the equation

which describes the stream lines in two‐dimensional flow of small amplitude in a stratified airstream. Solutions are computed for various variations of the parameter l as a function of height. (l2 = gβ/U2‐U−1∂2U/∂z2 is function of the wind and temperature variations with height in the airstream). To render the mathematical problem determinate the value of l2 is assumed to be constant above 16 km up to unlimited heights and by specifying the form of solution above 16 km consistent solutions are obtained for the troposphere little affected by the value of l2 assumed at high levels. The solutions include lee‐wave trains which diminish in amplitude downstream as well as those of constant amplitude. The method of solution results in the former appearing on the downstream side of the ridge only. (It is assumed that waves of constant amplitude can appear only on the downstream side).

Some typical displacements of the stream lines are illustrated in Figs. 3 to 10. They are similar to those computed by Queney (1947) and Scorer (1949) but it is demonstrated that lee waves may arise from variations of l2 with height additional to those specified by these authors.
Drop‐size distributions from various types of rain
Authors: Mason B. J. , Andrews J. B.
Published: February 2007

Notable differences are found in the size distribution of raindrops reaching the ground from frontal clouds exhibiting a radar melting‐band which is indicative of Bergeron‐type rain; from small, warm shower clouds in which the rain is formed by coalescence; and from thunderstorms. These differences are illustrated by typical drop‐size spectra and by plots of median‐volume drop diameter against rainfall intensity for the three classes.
A method of obtaining average bearing and incidence of rainfall
Authors: Rose C. W. , Farbrother H. G.
Published: February 2007

Three tilted raingauges are symmetrically disposed round a vertical axis, with their collecting openings facing outward at an angle of 45° to the horizontal. From the ratios of the catches the mean direction of travel of a rainstorm can be estimated, and also the ratio of horizontal to vertical velocity of raindrops, provided it is less than unity. At Namulonge, Uganda (17 mi N of Kampala), between September 1954 and May 1956, the most common direction of rainfall was from the south, in the sector 150° to 210°, and the velocity ratio exceeded tan 10° for 90 per cent of the total rain.
Differing water budgets in two adjacent reservoirs
Authors: Edwards Pamela
Published: February 2007

Before making experiments with surface films intended to reduce evaporation it was necessary to compare the variations of water level in two similar adjacent reservoirs. Although they were in relatively flat country significant differences in their water budgets appeared; they are described in this note.
Quasi‐periodic wind variations with height in the lower stratosphere
Authors: Sawyer J. S.
Published: February 2007

Quasi‐periodic wind variations with height have been commonly observed in the lower stratosphere by means of the radar‐sonde theodolite at Crawley. The atmospheric disturbances which give rise to these wind variations have a vertical dimension of 1 km or so, but their horizontal dimensions must be much greater, perhaps of the order of several hundred kilometers. Perturbation theory is used to show that slow ‘inertia oscillations’ with a period of the order of half a day might have such dimensions.
Ice accretion and turbulence on North Atlantic air routes
Authors: Crossley A. F.
Published: February 2007

Routine observations made in transport aircraft in January and July, 1955–57, are analysed to obtain the frequency of ice accretion in relation to air temperature and of turbulence in relation to wind speed and cloud. Comparative freedom from icing in the range 0° to – 3°C is attributed to the effects of kinetic heating. In January the frequency attains a maximum of 43 per cent of occasions in cloud at – 4° to – 7°C; in July 20 per cent at – 4° to – 11°C. There is a secondary maximum in both months near the lowest temperatures at which icing is reported, which is attributed to flight through the upper parts of convection cloud. The frequency of icing in July is generally much less than at the same temperatures in January.

Turbulence is reported on about 5 per cent of all occasions in January and on 2 per cent in July; in cloud the frequencies are 18 and 12 per cent respectively. The frequency of turbulence tends to increase with the wind speed.
Layer cloud over Southern England
Authors: Jones R. F.
Published: February 2007

599 morning weather reconnaissance flights from the Royal Aircraft Establishment, Farnborough, over a period of approximately four years have been examined to determine the frequency of occurrence and thickness of layer cloud over Southern England. The chance of encountering 4/8 or more layer cloud in any kilometre height range decreased with height from about 1 in 2 near the surface to about 1 in 50 at a height of 12 km. Cloud layers when encountered were more likely to exceed one or two kilometres depth in the upper troposphere than in the lower but the frequency of encountering a layer more than 1/12 km deep was about 7 to 8 per cent at all heights. About 1 in 9 of all flights encountered cloud above the melting level more than 3 km thick. An examination of clouds in the temperature band 0 to – 15°C suggested that conditions suitable for severe clear ice formation on some aircraft might be encountered on about one per cent of flights. The same examination suggests that seeding of layer clouds by silver‐iodide smokes should produce some detectable modification of the cloud sheet on about 8 days a year.
The meteorological significance of remote measurements of infra‐red emission from atmospheric carbon dioxide
Authors: Houghton J. T.
Published: February 2007

Observation from outside the atmosphere of the emission from different wavelength regions in the 15μ carbon‐dioxide band, would give information of the vertical temperature distribution between 10 and 50 km altitude. The measurements required are feasible using a Fabry‐Perot interferometer, and sample calculations of the depth in the atmosphere of the origin of this emission are presented.
An analysis of vertical wind‐fluctuations at heights between 500 and 5,000 ft
Authors: Smith F. B.
Published: February 2007

A series of records, totalling over 120 hr showing the vertical fluctuations of high‐response wind‐vanes positioned on a captive balloon cable, are analysed to give statistical information on turbulence at heights between 500 and 5,000 ft, for an eddy frequency range 0·003‐12 cycles min−1. The use of specially designed filter and smoothing circuits facilitates the determination of the angular standard deviation of the inclination of the vane, as a function of run of wind, and of spectra, length‐scales and other parameters of turbulence. 18 spectra are given which show well‐defined peaks. Except in very stable conditions, the high wave‐number forms of the spectra are generally consistent with the existence of an inertial sub‐range. Estimates of the length‐scale, again excluding very stable conditions, do not apparently vary with height and average about 300 m. Intensity is found to depend on stability and to decrease in a very marked way with increasing wind speed, a result peculiar to these heights. This variation, applicable to specified meteorological conditions, is shown to have value in the determination of the spread of both continuous‐source plumes and clusters of particles according to recent treatments.