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A magnetic spectrometer has been developed for the AWAKE experiment at CERN in order to measure the energy distribution of bunches of electrons accelerated in wakefields generated by proton bunches in plasma. AWAKE is a proof-of-principle experiment for proton-driven plasma wakefield acceleration, using proton bunches from the SPS. Electron bunches are accelerated to O (1 GeV) in a rubidium plasma cell and then separated from the proton bunches via a dipole magnet. The dipole magnet also induces an energy-dependent spatial horizontal spread on the electron bunch which then impacts on a scintillator screen. The scintillation photons emitted are transported via three highly-reflective mirrors to an intensified CCD camera, housed in a dark room, which passes the images to the CERN controls system for storage and further analysis. Given the known magnetic field and determination of the efficiencies of the system, the spatial spread of the scintillation photons can be converted to an electron energy distribution. A lamp attached on a rail in front of the scintillator is used to calibrate the optical system, with calibration of the scintillator screen’s response to electrons carried out at the CLEAR facility at CERN. In this article, the design of the AWAKE spectrometer is presented, along with the calibrations carried out and expected performance such that the energy distribution of accelerated electrons can be measured. A magnetic spectrometer has been developed for the AWAKE experiment at CERN in order to measure the energy distribution of bunches of electrons accelerated in wakefields generated by proton bunches in plasma. AWAKE is a proof-of-principle experiment for proton-driven plasma wakefield acceleration, using proton bunches from the SPS. Electron bunches are accelerated to $\mathcal{O}$(1 GeV) in a rubidium plasma cell and then separated from the proton bunches via a dipole magnet. The dipole magnet also induces an energy-dependent spatial horizontal spread on the electron bunch which then impacts on a scintillator screen. The scintillation photons emitted are transported via three highly-reflective mirrors to an intensified CCD camera, housed in a dark room, which passes the images to the CERN controls system for storage and further analysis. Given the known magnetic field and determination of the efficiencies of the system, the spatial spread of the scintillation photons can be converted to an electron energy distribution. A lamp attached on a rail in front of the scintillator is used to calibrate the optical system, with calibration of the scintillator screen's response to electrons carried out at the CLEAR facility at CERN. In this article, the design of the AWAKE spectrometer is presented, along with the calibrations carried out and expected performance such that the energy distribution of accelerated electrons can be measured.

Beam Delivery Simulation (BDSIM) is a program that simulates the passage of particles in a particle accelerator. It uses a suite of standard high energy physics codes (Geant4, ROOT and CLHEP) to create a computational model of a particle accelerator that combines accurate accelerator tracking routines with all of the physics processes of particles in Geant4. This unique combination permits radiation and detector background simulations in accelerators where both accurate tracking of all particles is required over long range or over many revolutions of a circular machine, as well as interaction with the material of the accelerator., Comment: 20 pages, 17 figures. Accepted for publication 28th Jan 2020

The Advanced Proton Driven Plasma Wakefield Acceleration Experiment (AWAKE) aims at studying plasma wakefield generation and electron acceleration driven by proton bunches. It is a proof-of-principle R&D experiment at CERN and the world's first proton driven plasma wakefield acceleration experiment. The AWAKE experiment will be installed in the former CNGS facility and uses the 400 GeV/c proton beam bunches from the SPS. The first experiments will focus on the self-modulation instability of the long (rms ~12 cm) proton bunch in the plasma. These experiments are planned for the end of 2016. Later, in 2017/2018, low energy (~15 MeV) electrons will be externally injected to sample the wakefields and be accelerated beyond 1 GeV. The main goals of the experiment will be summarized. A summary of the AWAKE design and construction status will be presented., 7 pages, 7 figures, 2 tables

We measure the effects of transverse wakefields driven by a relativistic proton bunch in plasma with densities of 2.1×1014 and 7.7×1014 electrons/cm3. We show that these wakefields periodically defocus the proton bunch itself, consistently with the development of the seeded self-modulation process. We show that the defocusing increases both along the bunch and along the plasma by using time resolved and time-integrated measurements of the proton bunch transverse distribution. We evaluate the transverse wakefield amplitudes and show that they exceed their seed value (

A new laser-wire has been installed in the extraction line of the ATF at KEK. It aims at demonstrating that laser-wires can be used to measure micrometre scale beam size. In parallel, studies have been made to specify a laser suitable for the ILC laser-wires. © Indian Academy of Sciences.

J Appl Physiol 120: 1489, 2016; doi:10.1152/japplphysiol.00354.2016. Letter to the Editor Last Word on Viewpoint: Hypercapnia is more important than hypoxia in the neuro-outcomes of sleep-disordered breathing David Wang, 1,2,3,4 Robert J. Thomas, 5 Brendon J. Yee, 1,2,3,4 and Ronald R. Grunstein 1,2,3,4 Sleep & Circadian Group, Woolcock Institute of Medical Research, The University of Sydney, Australia; 2 Department of Respiratory and Sleep Medicine, Royal Prince Alfred Hospital, Sydney Local Health District, Sydney, Australia; 3 NHMRC Centre of Research Excellence in Sleep Medicine-NeuroSleep, Australia; 4 Central Clinical School, The University of Sydney, Sydney, Australia; 5 Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts Address for reprint requests and other correspondence: D. Wang, Woolcock Institute of Medical Research, 431 Glebe Point Road, Glebe NSW 2037, Australia (e-mail: david.wang@sydney.edu.au). http://www.jappl.org ciated neuronal injuries. This is a complex area. Compliant CPAP therapy can generally improve SDB-related neurobe- havioral impairment (2). We reflect that the difference between CPAP and O 2 supplement therapy is that CPAP is more likely to improve hypoxia, hypercapnia, and sleep fragmentation, whereas O 2 supplementation only improves hypoxia. Other comments are generally supportive to our Viewpoint and provided more in-depth exploration of the complex mech- anism between hypoxia-hypercapnia interaction and neural pathophysiology and raised more thought-provoking questions. In research studies, it is important to check 1) is the hypoxia model actually testing the mixed effect of hypoxia and hyper- capnia/hypocapnia? 2) is the hypoxia level comparable to OSA level, particularly for animal studies? The effect of hypercapnia has been long ignored and signif- icantly understudied and it is the time to think beyond hypoxia. Hypercapnia, particularly the interaction between hypoxia and hypercapnia/hypocapnia should be the next frontier of research in SDB neuro-outcomes. Measurement is a key requirement and presents opportunities for cost-effective technological de- velopment. DISCLOSURES No conflicts of interest, financial or otherwise, are declared by the author(s). AUTHOR CONTRIBUTIONS D.W., R.J.T., and R.R.G. conception and design of research; D.W. drafted manuscript; D.W., R.J.T., B.J.Y., and R.R.G. edited and revised manuscript; D.W., R.J.T., B.J.Y., and R.R.G. approved final version of manuscript. REFERENCES 1. Olaithe M, Eastwood PR, Bucks RS, Deacon NL, Malhotra A, Kumar VHS, Zuo L, Chuang CC, Schotland H. Comments on Viewpoint: Hypercapnia is more important than hypoxia in the neuro-outcomes of sleep-disordered breathing. J Appl Physiol; doi:10.1152/japplphysiol.00327.2016. 2. Rosenzweig I, Glasser M, Polsek D, Leschziner GD, Williams SC, Morrell MJ. Sleep apnoea and the brain: a complex relationship. Lancet Resp Med 3: 404-414, 2015. 3. Wang D, Piper AJ, Yee BJ, Wong KK, Kim JW, D’Rozario AL, Rowsell L, Dijk DJ, Grunstein RR. Hypercapnia is a key correlate of EEG activation and daytime sleepiness in hypercapnic sleep-disordered breathing patients. J Clin Sleep Med 10: 517–522, 2014. 4. Wang D, Thomas RJ, Yee BJ, Grunstein RR. Viewpoint: Hypercapnia is more important than hypoxia in the neuro-outcomes of sleep-disordered breathing. J Appl Physiol; doi:10.1152/japplphysiol.01008.2015. 5. Wang D, Yee BJ, Wong KK, Kim JW, Dijk DJ, Duffin J, Grunstein RR. Comparing the effect of hypercapnia and hypoxia on the electroen- cephalogram during wakefulness. Clin Neurophysiol 126: 103–109, 2015. 8750-7587/16 Copyright © 2016 the American Physiological Society Downloaded from http://jap.physiology.org/ by 10.220.33.2 on August 16, 2016 We agree with Olaithe and colleagues (see Ref. 4) that we should never “put hypoxia to bed.” The reason is simple: in clinical sleep-disordered breathing (SDB) scenarios, there are inseparable combinations of repetitive hypoxia and hypercapnia or hypocapnia (ventilatory overshoot mecha- nisms) events. We believe that any SDB neuro-outcomes should consider a combination effect rather than blame hyp- oxia alone, given the evidence we presented. Assuming that measurement challenges applicable to large studies are over- come, novel interactive hypoxia/hypercapnia indices may bet- ter explain the individual vulnerability to SDB neuro-impair- ment. Deacon and Malhotra (1) questioned that our major evidence for the relationship between hypercapnia and neurocognitive deficit was based on hypercapnic SDB patients (3) and most of the OSA patients do not have daytime hypercapnia. We note a lack of reliable and cost-effective widely applicable tools to precisely measure P CO 2 continuously in ordinary OSA patients overnight. We studied hypercapnic SDB patients, which al- lowed us to use the gold standard ABG P CO 2 measurement during wake and there is a wide spectrum of change in P CO 2 after treatment, which makes it possible to correlate with EEG activation change (3). Importantly, to minimize this limitation, we conducted a clinical experiment on normal volunteers to examine the generic effect of hypercapnia and hypoxia (com- parable to levels seen in OSA) on EEG activation (5). Again we found significant correlation between hypercapnia and slowing in EEG, whereas a similar effect was not found with hypoxia alone (Fig. 1 in Viewpoint) (5). This finding is also supported by human brain imaging studies, undersea diver experiments, and a number of animal studies (see Viewpoint, Ref. 4). We agree that most of the OSA patients do not have daytime hypercapnia; they do not have daytime hypoxemia either and that does not exclude hypoxia as a mechanism for SDB related neuro-impairment. More work with less bias to hypoxia is required. Supplemental O 2 does not generally improve SDB neuro- impairment despite improving overnight oxygen saturation; both Deacon and Malhotra and Zuo and Chuang (see Ref. 1) suggest that may be due to irreversible oxidative stress-asso- TO THE EDITOR

Enterohaemorrhagic Escherichia coli (EHEC) comprise a group of animal and zoonotic pathogens of worldwide importance. Our previous research established that intestinal colonization of calves by EHEC serotypes O5 : H– and O111 : H– requires EHEC factor for adherence (Efa-1), also known as lymphostatin (LifA). Towards an understanding of the mode of action of Efa-1/LifA, chromosomal in-frame deletions of predicted glycosyltransferase (DXD) and cysteine protease (CHD) motifs were created in a Δstx1 derivative of EHEC O26 : H–. The magnitude and duration of faecal excretion of EHEC O26 : H– were significantly reduced by null mutation of efa-1/lifA, but were not impaired by ΔDXD or ΔCHD mutations, in contrast to observations made with truncated Efa-1/LifA mutants of Citrobacter rodentium in mice. Although C. rodentium Efa-1/LifA influences the induction of colonic hyperplasia in mice, EHEC O26 : H– Efa-1/LifA was not required for fluid accumulation or neutrophil recruitment in bovine ileal loops. In contrast to observations with EHEC O5 : H– or O111 : H– mutants, inactivation of efa-1/lifA in EHEC O26 : H– did not significantly affect adherence or secretion of type III secreted proteins that play pivotal roles in calf colonization. Lymphostatin activity could not be reliably demonstrated in lysates of EHEC O26 : H–; however, deletion of the glycosyltransferase and cysteine protease motifs in Efa-1/LifA from enteropathogenic E. coli O127 : H6 abolished lymphostatin activity. Our data uncouple the role of Efa-1/LifA in calf colonization from effects on type III secretion and reinforce the potential for pathotype- and serotype-specific phenotypes.

BDSIM, a code for particle–matter interaction studies in accelerators, is presented. BDSIM is a toolkit for simulation of particle transport in accelerator beam-lines. It provides a collection of classes representing typical accelerator components, a collection of physics processes for fast tracking, procedures of run-time geometry construction, analysis routines and tools to interface it to other particle tracking codes.

2nd European Advanced Accelerator Concepts Workshop, EAAC2015, La Biodola, Isola d'Elba, Italy, 13 Sep 2015 - 19 Sep 2015 ; Nuclear instruments & methods in physics research / A 829, 3 - 16(2016). doi:10.1016/j.nima.2015.12.050, This paper describes the conceptual steps in reaching the design of the AWAKE experiment currently under construction at CERN. We start with an introduction to plasma wakefield acceleration and the motivation for using proton drivers. We then describe the self-modulation instability – a key to an early realization of the concept. This is then followed by the historical development of the experimental design, where the critical issues that arose and their solutions are described. We conclude with the design of the experiment as it is being realized at CERN and some words on the future outlook. A summary of the AWAKE design and construction status as presented in this conference is given in Gschwendtner et al., Published by North-Holland Publ. Co., Amsterdam

Presented here is a single phase, high yield synthesis of a dioctyldiselenide ligand that has been achieved with shelf-available chemicals in a short time, at room temperature, and without the need for an inert environment.

The KEK Accelerator test facility (ATF) extraction line laser-wire system has been upgraded last year allowing the measurement of micron scale transverse size electron beams. The most recent measurements using the upgraded system are presented. The ATF-II extraction line design call for the major upgrade of the existing laser-wire system. We report on the hardware upgrades, including the major hardware upgrades to the laser transport, the laser beam diagnostics line, and the mechanical control systems.

A laser-wire transverse electron beam size measurement system has been constructed and operated at the Accelerator Test Facility (ATF) extraction line at KEK. The construction of the system is described in detail along with the environment of the ATF related to the laser wire. A special set of electron beam optics was developed to generate an approximately $1\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$ vertical focus at the laser-wire location. The results of our operation at the ATF extraction line are presented, where a minimum rms electron beam size of $4.8\ifmmode\pm\else\textpm\fi{}0.3\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$ was measured, and smaller electron beam sizes can be measured by developing the method further. The beam size at the laser-wire location was changed using quadrupoles and the resulting electron beam size measured, and vertical emittance extracted.

Research in South Africa has highlighted the dependence of biological phosphate removal mechanisms on the presence of certain minimum concentrations of some readily biodegradable materials including interalia volatile fatty acids. Generation of these compounds was achieved on an experimental basis at the Johannesburg Northern Works by the fermentation of primary sludge either in primary settling tanks or off-line in high rate “acid” digesters. Elutriation of the volatile fatty acids from the sludge was achieved by recycling the sludge to the influent sewage stream. Significant improvements in phosphate removal were observed and it was decided to design primary sludge treatment facilities to specifically generate the volatile fatty acids. This paper describes the design philosophy adopted and discusses the preliminary results obtained from the recently commissioned plant at the Johannesburg Northern Works and Bushkoppie plants.

The Johannesburg City Council has operated biological and chemical nutrient removal wastewater treatment plants for the past 15–16 years. With the advent of more sophisticated sludge handling techniques, problems have been experienced with the recycle of phosphorus-rich sludge processing liquors to the liquid phase. These problems are expected to increase in the future. This paper describes laboratory and pilot scale experiments to determine viable methods for phosphorus removal from sludge liquors and ways of obviating phosphorus release from phosphorus-rich activated sludges. The design of new full-scale plants being constructed to pretreat phosphorus-rich sludges prior to dewatering are also discussed. The paper also describes innovative process layouts for sludge treatment keeping in mind various options for final sludge disposal. Emphasis is placed on the pre-aeration and phosphate precipitation from anaerobically digested and raw primary sludges and techniques for the thickening and dewatering of primary and waste activated sludges to minimize phosphate release into the liquors so produced. The technique of sludge thickening on linear screens is described and the coupling of linear screens to belt presses to complete the dewatering operation.

Background Salmonella enterica is a facultative intracellular pathogen of worldwide importance. Over 2,500 serovars exist and infections in humans and animals may produce a spectrum of symptoms from enteritis to typhoid depending on serovar- and host-specific factors. S. Enteritidis is the most prevalent non-typhoidal serovar isolated from humans with acute diarrhoeal illness in many countries. Human infections are frequently associated with direct or indirect contact with contaminated poultry meat or eggs owing to the ability of the organism to persist in the avian intestinal and reproductive tract. The molecular mechanisms underlying colonisation of poultry by S. Enteritidis are ill-defined. Targeted and genome-wide mutagenesis of S. Typhimurium has revealed conserved and host-specific roles for selected fimbriae in intestinal colonisation of different hosts. Here we report the first systematic analysis of each chromosomally-encoded major fimbrial subunit of S. Enteritidis in intestinal colonisation of chickens. Results The repertoire, organisation and sequence of the fimbrial operons within members of S. enterica were compared. No single fimbrial locus could be correlated with the differential virulence and host range of serovars by comparison of available genome sequences. Fimbrial operons were highly conserved among serovars in respect of gene number, order and sequence, with the exception of safA. Thirteen predicted major fimbrial subunit genes were separately inactivated by lambda Red recombinase-mediated linear recombination followed by P22/int transduction. The magnitude and duration of intestinal colonisation by mutant and parent strains was measured after oral inoculation of out-bred chickens. Whilst the majority of S. Enteritidis major fimbrial subunit genes played no significant role in colonisation of the avian intestines, mutations affecting pegA in two different S. Enteritidis strains produced statistically significant attenuation. Plasmid-mediated trans-complementation partially restored the colonisation phenotype. Conclusion We describe the fimbrial gene repertoire of the predominant non-typhoidal S. enterica serovar affecting humans and the role played by each predicted major fimbrial subunit in intestinal colonisation of the primary reservoir. Our data support a role for PegA in the colonisation of poultry by S. Enteritidis and aid the design of improved vaccines.

The development of cardiac control in association with terrestrial respiration patterns was examined throughout the period of maternal dependence in Australian fur seal pups. Resting eupnoic heart rate and respiration rate were significantly correlated (r 2 = 0.49) and both decreased with age (P

On 13C1-labeled octanethiol-protected 2.7 nm Pd nanoparticle surfaces, it has been observed that the 13C1 NMR of the alpha-carbon shows a peak centered around 38 ppm (with respect to tetramethylsilane (TMS)), which virtually coincides with that of the alpha-carbons in a dioctyl-disulfide molecule (39.3 ppm), and the corresponding 13C1 spin-spin relaxation becomes nonexponential. In addition, the infrared spectrum of the same sample shows that the ligands have a 100% gauche conformation, which is also consistent with a dioctyl-disulfide arrangement. By comparing with data obtained on 13C1-labeled octanethiol-protected 2.8 nm Au nanoparticles, we propose that a dioctyl-disulfide structure of the ligands is formed on the octanethiol-protected Pd nanoparticle surface, in contrast to the thiolate structure proposed on the Au nanoparticles. In addition, CO adsorption experiments show no sign of a PdS layer formed on the Pd nanoparticle surface. Furthermore, data taken over a period of more than 1 year show that the Pd nanoparticles are rather stable in organic solvents (for instance benzene), although slow degradation does happen and oxygen seems to play an important role in accelerating the degradation.

In the present investigation, in vivo microdialysis was used to measure the concentration of estrogen in the parabrachial nucleus (PBN) and plasma of male and ovariectomized female Sprague-Dawley rats supplemented with either estrogen (OVX-E(2)) or saline (OVX-S) following visceral afferent activation. Analysis of dialysate samples prior to vagal stimulation and in non-stimulated controls revealed a continuous concentration of estrogen in the PBN for all treatment groups (male, 38 +/-4 pg ml(-1); OVX-E(2), 38+/-5 pg ml(-1); OVX-S, 33 +/- 4 pg ml(-1)). This concentration of estrogen in the PBN was significantly increased during vagal stimulation in all groups (male, 64+/-4 pg ml(-1); OVX-E(2), 104+/-9 pg ml(-1); OVX-S, 80+/-6 pg ml(-1); P0.05) and returned to pre-stimulation values within 2 h following termination of the stimulation. Immunohistochemical analysis revealed that estrogen receptor (ERalpha and ERbeta) density in males and ovariectomized saline-replaced female rats was significantly lower than that of estrogen-replaced female rats. These results suggest that estrogen is released into the PBN by an increase in visceral afferent traffic, however, alterations in estrogen receptor populations in the PBN may contribute to an attenuated physiological role of estrogen in the PBN of male and saline-replaced ovariectomized female rats.

Severe closed head-injury results in a multitude of long-lasting cognitive deficits. ERPs can effectively complement the more traditional behavioural measures to provide information that is not available through any other means. It is now fairly clear that a late positive wave, P3, associated with contextual updating is attenuated and prolonged in a variety of conditions in the head-injured. It is also possible that measures of selective attention such as the processing negativity may be abnormal in this group. A more definitive statement will, however, have to wait the results of further investigations. A number of investigators have now indicated that cognitive processing is slowed in the head-injured. Again, ERPs have been instrumental in explaining why it is slowed. Decision-making time as measured by RT is generally longer than P3 latency. Because P3 latency is delayed in the head-injured, the time required for evaluation of the stimulus (recognition and classification) is slowed in the head-injured. The additional delay in RT must, however, be explained by other processes, most probably a response bias that perhaps emphasizes accuracy at a cost of speed. Such a strategy can be manipulated if the patient is provided with cues about their speed of responding. Finally, ERPs have been instrumental in explaining possible reasons for cognitive slowing. A powerful CNV technique may permit the categorization of the head-injured into at least 2 distinctive groups: those that tend to underprocess information (perhaps as a result of apathy or a lack of motivation) and those that tend to overprocess (perhaps as a result of an inefficient and needless processing of irrelevant information resulting in fatigue). The extent to which the different modes of information processing are related to the site of brain injury and possible personality change remains an issue of speculation.

Deacon, E. L., O'Reilly, M. J. J. and Williams, A. L. (1979).Aust. Paediatr. J., 15, 248–254. Some statistical and climatological aspects of the incidence of the sudden infant death syndrome. SIDS data for the Statistical Divisions of Melbourne (1973–77) and Brisbane (1968–77) show there to be only a small seasonal variation in the deaths of infants 2–13 weeks of age, but for the older cases the variation is much stronger, particularly in the Melbourne area. There is no evidence of any time-clustering of deaths in the 2–13 weeks age group in either area, nor is there in the 14–25 weeks age group in Melbourne's colder months. Consistent with a random process, the variance of Brisbane's annual number of cases from the 10-year mean is close to that for a Poisson distribution. In conjunction with published data for other communities. It is found that the incidence of SIDS correlates closely with a climatic index in terms of mean annual percentage of cold-wet weather. This suggests a connection with the amount of respiratory infection in the general population, but other factors may be involved, such as time spent outdoors.

The radon deficit method of measuring gas transfer from the sea has so far failed to give reliable information on the dependence of transfer velocity on wind speed owing to the 5.5 day mean lifetime of the radon nuclide. Calculations with a simple model illustrate how the normal variations in wind speed encountered during trials at sea cause even a strong dependence to be largely obscured.

The rates of transfer of radon from sea to air estimated by Peng et al. (1979) from an extensive series of observations of radon profiles made during the Geosecs oceanographical cruises, are reexamined in relation to wind speed dependence. It is concluded that there is a significant increase with wind speed, but the extent of the increase is uncertain. At 7 m s-1, the transfer velocity is indicated to be some 33%; greater than the BOMEX value of Broecker and Peng (1974) — a reasonably close agreement These rates exceed the theoretical smooth-surface value by a factor of two or three. It is shown that little of this excess can be attributed to the surface dilation effect of capillary waves.

Observations over grassland of the turbulent kinetic energy in a band of frequencies in the inertial subrange of the spectrum of the streamwise wind component are related to the stress indicated by the wind profiles. The object is to determine the effective Kolmogoroff constant, α UB which accords with the assumption of balance between turbulent energy production and dissipation. The mean from 60 half-hour runs made under stability conditions ranging from neutral to moderate instability is α UB = 0.62.

The surprisingly small wind stress on the water over a fringing coral reef, which was observed by Hicks et al. (1974), raised the question as to whether this was mainly a shallow water effect or could be the effect of a surface film of organic surfactant. This is considered in relation to other evidence on the shallow water effect and to the fact that coral secretes mucus containing much cetyl palmitate (Benson and Muscatine, 1974). On hydrolysis this yields two powerful surfactants of a type found in natural sea slicks, so the surface film effect is concluded to be the predominant influence. It is conjectured that mucus secretion may have a role in reef ecology by producing quieter water conditions for the more delicate forms of coral typically found some distance shoreward of the windward reef edge.

A treatment based on Reichardt's formulation of the velocity profile in turbulent flow over a smooth plane surface is shown to give good agreement with published data on the boundary layer transfer of heat and mass over a wide range of Prandtl (or Schmidt) number, s. Applied to transfer to a water surface, agreement with published laboratory results is also good for low air speeds (smooth water). Comparison with observations for the sea shows there is little difference between the calculated evaporation coefficient and those reported for the sea with winds of ∼7 m s -1 . This is consistent with sea trials having so far detected little increase of evaporation and heat transfer coefficients with wind speed over the range 4–10 m s -1 . The air/water transfer of non-reactive gas is governed by the resistance of the viscous sublayer of water, and the smooth surface treatment gives the transfer velocity ( V L ) on a liquid phase basis as V L = 0.082 ( p a /p w ) 1/2 s -2/3 u* where p a p w is the density ratio, air/water, and u * = friction velocity of the surface air flow. The agreement between this formula and published wind tunnel results is good for the smooth water condition. At higher wind speeds transfer exceeds the calculated value and appears then to increase roughly in proportion to the square of the wind speed. DOI: 10.1111/j.2153-3490.1977.tb00746.x

Experiments made in a periodically fluctuating wind current show that Sheppard and Meteorological office pattern cup anemometers over-estimate the mean wind velocity roughly in accordance with Schrenk's analysis except that the overestimation decreases somewhat more rapidly with increase of Schrenk's parameter K (defined in quation 2 below) than is indicated by the analysis. Changing the cup form from the hemispherical to the conical pattern (other characteristics being constant) results in only a slight decrease in the over-estimation error over a limited range of K.

A 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 a Geophysical Memoir of the Meteorological Office.

Reported failures of a generalized wind-profile equation to predict correctly the shearing stress under certain conditions are found to be associated with low wind speeds close to the surface. The increase of drag coefficient of the surface-roughness elements (e.g., grass blades) at low Reynolds numbers is the source of these discrepancies.

Data on the relationship of the surface wind to the geostrophic wind at Porton Down, Salisbury Plain, are presented for various stability conditions and analysed in the light of the Rossbynumber similarity theory. For near-neutral conditions, the geostrophic drag coefficients for geostrophic wind speeds 5 to 15 m s-1 are close to those found by other workers but at higher speeds the values are low. Comparisons of geostrophic and radar wind speeds for ⋍900-m height, suggest that undetectably small mean cyclonic curvatures of the trajectories of the air are responsible for this departure.

An inexpensive and simple form of radiometer capable of attachment to the American Bureau of Standards type radiosonde is described: it measures the upward flux of longwave radiation when used on night ascents. A slight modification to the telemetry circuit of the standard radiosonde enables the radiation signals to be obtained in addition to the usual pressure, temperature and humidity information.

Two types of electric recording cup anemometer employing the Sheppard three-cup rotor are described, the instruments being suitable for applications where results of high accuracy are desired and for the measurement of light winds, the stopping speeds of the anemometers being as low as 0.15 m./sec. (30 ft./min.). High sensitivity and constancy of calibration is achieved by minimizing the bearing friction and the torque necessary to operate the impulsing device. A source of heat in the anemometer body is found to be very effective in preventing bearing corrosion and consequent changes of friction. In the first type of anemometer a photoelectric impulsing system is employed, while the second arrangement (the `micro-contact anemometer') uses a very light electric contact in conjunction with a thermionic valve. Photographic recording of the electric counters on bromide paper is found to be the most convenient recording system. Both types of anemometer have functioned satisfactorily during considerable periods of exposure to the British climate.

Relatively simple instruments for measuring the heat flux into or out of the soil are described together with methods of calibration. One form consists of a suitable metal disc of sandwich construction producing a thermal e.m.f. proportional to the heat flux through the disc, which is placed in the soil just below the surface. Details are also given of another form of flux plate which is suitable for continuous recording using a thread recording galvanometer.

Observations of the vertical gradients of wind and temperature over the sea are presented. They indicate a drag coefficient for neutral stability increasing but slightly up to wind speeds of 14 m/sec. The mean value for the open sea is found to be approximately 0.0012 (for 10-meter reference height), but the number of observations on which this is based is much smaller than for the enclosed waters of Port Phillip. Analysis of the effects of stability on the wind gradient in terms of similarity theory gives some evidence that the concepts developed as a result of work over land surfaces may be applied successfully to conditions over the sea. The constant a in the ‘log+linear’ formulation for near-neutral profiles is found to have a value of around 3.5, a value similar to that found from some series of observations over land surfaces.

Heavy rainfalls during the monsoon seasons at Djakarta (1864-1945) and Mangalore (1901-1950) are found to occur more frequently at certain epochs of the lunar synodic cycle than at others. The effect is not of high statistical significance, but the results are sufficiently suggestive and in line with evidence from U.S.A. (Brier and Bradley 1964) to warrant a much more extensive study of Indian rainfall statistics. The indications that the lunar effect is much stronger in years of below average sunspot number, here and in U.S.A., may help in the elucidation of underlying processes.

It is shown that Swinbank's empirical formula for the long-wave radiation from clear skies can be derived from existing knowledge of atmospheric emission by taking account of the moderately strong correlation at most places between screen temperature and the amount of water vapour overhead.