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Kennicutt, M.C. et. al.-- 17 pages, 3 figures, The Antarctic Roadmap Challenges (ARC) project identified critical requirements to deliver high priority Antarctic research in the 21st century. The ARC project addressed the challenges of enabling technologies, facilitating access, providing logistics and infrastructure, and capitalizing on international co-operation. Technological requirements include: i) innovative automated in situ observing systems, sensors and interoperable platforms (including power demands), ii) realistic and holistic numerical models, iii) enhanced remote sensing and sensors, iv) expanded sample collection and retrieval technologies, and v) greater cyber-infrastructure to process ‘big data’ collection, transmission and analyses while promoting data accessibility. These technologies must be widely available, performance and reliability must be improved and technologies used elsewhere must be applied to the Antarctic. Considerable Antarctic research is field-based, making access to vital geographical targets essential. Future research will require continent- and ocean-wide environmentally responsible access to coastal and interior Antarctica and the Southern Ocean. Year-round access is indispensable. The cost of future Antarctic science is great but there are opportunities for all to participate commensurate with national resources, expertise and interests. The scope of future Antarctic research will necessitate enhanced and inventive interdisciplinary and international collaborations. The full promise of Antarctic science will only be realized if nations act together, The authors recognize the financial support that made the Scan and ARC possible. The Council of Managers of National Antarctic Programs (COMNAP), the Tinker Foundation and the Scientific Committee on Antarctic Research (SCAR) provided the majority of the funding for this project including the costs of travel and participation of invited, non-COMNAP workshop attendees. In-kind support was provided by many COMNAP-Member national Antarctic programmes including Dirección Nacional del Antártico (DNA, Argentina), Australian Antarctic Division (AAD, Australia), Programa Antártico Brasileiro (PROANTAR, Brazil), Instituto Antártico Chileno (INACH, Chile), Polar Research Institute of China (PRIC, China), Instituto Antártico Ecuatoriano (INAE, Ecuador), Institut Polaire Français Paul Emile Victor (IPEV, France), Alfred Wegener Institute (AWI, Germany), National Institute of Polar Research (NIPR, Japan), Korea Polar Research Institute (KOPRI, Republic of Korea), Antarctica New Zealand (New Zealand), Arctic and Antarctic Research Institute (AARI, Russia), Spanish Polar Committee (CPE, Spain), British Antarctic Survey (BAS, UK), and the US National Science Foundation (NSF, USA)

Two field trials using four New Zealand wheat cultivars were undertaken to observe the effects of nitrogen and sulfur fertilization on protein composition, mixing requirements, and dough strength and to compare the results with that observed with a single cultivar, Otane. The results confirmed that adequate sulfur fertilization was necessary to ensure lower dough mixing requirements. The existence of a nexus between mixing requirements and dough strength was confirmed and genotype has significant effects on it. Variation in the content of HMW-GS in the protein corresponded to changes in dough mixing requirement of Otane. Across the four cultivars, dough mixing requirements (mechanical dough development work input and mixograph development time) and dough strength (Extensigraph resistance to extension) depended on different aspects of protein composition. As the content of polymeric proteins increased, MDD work input increased, but mixograph development time decreased, while the effect on Rmax was...

The effect on physical dough properties of nitrogen and sulfur fertilizer applied during cultivation was observed in two trials using the bread wheat (Triticum aestivum) cultivar Otane. Wheat flours from both trials were evaluated for physical dough properties under laboratory conditions and also under industrial conditions in the second trial. The laboratory and industrial optimum mechanical dough development (MDD) work input (WI) significantly increased when nitrogen (N) fertilizer was applied without sulfur fertilizer (S) during crop cultivation. With combined N and S fertilization, laboratory and industrial WI remained close to levels for grain grown without fertilizer. Reductions in extensigraph resistance to extension (Rmax) and increases in extensigraph extensibility (Ext) due to S fertilization also were observed. None of the observed changes in WI, Rmax, or Ext due to S fertilization significantly affected end-product quality as measured by loaf volume, crumb grain, and bake score. The n...

The use of a laboratory-scale mixer for predicting the mixing requirement of flours in an industrial-scale mixer was investigated by measuring the work input required to mix a range of flours to peak consistency on both a laboratory-scale and an industrial-scale mechanical dough development (MDD) mixer. The industrial mixer used was a Tweedy-type mixer, and the mixing optimum was determined using a probe that sensed changes in dough consistency. Work input was estimated from mixer motor power, taking into account expected motor and drive chain losses, and from dough temperature rise measurements. The laboratory mixer used twin flat-bladed rotors; mixing optimum and work input were determined from the torque measurement. Work inputs from both mixers were highly correlated (r2 = 0.88) but with a large offset (the industrial mixer requiring more work to develop the dough). The two methods of measuring industrial mixer work inputs gave slightly different results leading to uncertainty as to the actua...

The peak current, power, and half-peak duration of the current through a flash tube are determined. The flash tube may be considered as an element in an R–L–C circuit whose electrical behavior is dependent on a single parameter. The variation of tube current with voltage is examined and the plasma impedance determined. The intensity, rise time, decay time, and half-peak duration of the radiation pulse are determined for a range of tube geometries and gas pressures. The duration of the radiation pulse depends on that of the current, but the intensity is dependent on both gas pressure and power density.

The sleeping patterns of 874 infants aged 1-12 months were recorded by parents over a 6 day period. The most striking feature of the results was the wide range in total hours slept by infants of the same age, for example, the average total sleeping time per 24 h period for 4 month old infants was 14.8 h with a range of 11.0-19.3 h. Furthermore, over the 6 day period, individual infants showed wide variations in their sleeping times with a range as great as 12 h. Despite these wide variations, several clear trends emerged: from 1 to 8 months, a decrease with age of the average number of hours slept per 24 h period; and from 8 to 12 months, and a continuing shift towards a dominance of night over day sleep. The frequency of night wakings was, on average, 77%, a finding that contrasted sharply with parental perception of frequency of night waking; the transition from bassinet/carrycot to cot was most common between 3 and 4 months of age; 25% of babies slept with the light on, 9% used a dummy, and 37% sucked their fingers; first-born infants woke significantly less often at night than those with one or more sibling. These results provide an important comparative data set on the sleep patterns of infants.

The in vitro micropropagation of oca (Oxalis tuberosa Mol., Oxalidaceae) on a medium with 30 g/litre versus 60 g/litre sucrose had no effect on multiplication rates and general plant phenotype. The only differences noted at the higher sucrose concentration were shortened internodes and more robust stem tissue, which provided a plant growth form more appropriate for micropropagation and transplantation out of culture. Substantially increased starch concentrations were measured in leaves, stems, and roots of the oca plants cultured on the high‐sucrose medium. Oca plants cultured in vitro on a medium with 60 g/litre sucrose showed markedly improved growth in soil following transfer out of culture. This was attributed to the in vitro plants accumulating and storing more reserves when grown on the high‐sucrose medium.

The alternative oxidase is found in the inner mitochondrial membranes of plants and some fungi and protists. A monoclonal antibody raised against the alternative oxidase from the aroid lily Sauromatum guttatum has been used extensively to detect the enzyme in these organisms. Using an immunoblotting strategy, the antibody binding site has been localised to the sequence RADEAHHRDVNH within the soybean alternative oxidase 2 protein. Examination of sequence variants showed that A2 and residues C-terminal to H7 are required for recognition by the monoclonal antibody raised against the alternative oxidase. The recognition sequence is highly conserved among all alternative oxidase proteins and is absolutely conserved in 12 of 14 higher plant sequences, suggesting that this antibody will continue to be extremely useful in studying the expression and synthesis of the alternative oxidase.

The microwave power scattered by a circular cylinder of inhomogeneous plasma contained in a glass tube is computed with the aid of the Frobenius method. It is found that computed and experimental values are in good agreement in the range 0.2< lambda /R

A line at the subharmonic frequency omega 0/2 has been detected in the radiation backscattered from plasmas produced by irradiation of plane targets with a neodymium laser. The dependence of the threshold irradiance on the density scale length over the range 1012 to 1015 W cm-2 has been determined.

A general dispersion relation has been derived for high frequency electromagnetic drift waves in the range omegaci

By using flashes of microsecond duration it has been possible to obtain a series of shadowgrams showing the development of steadily propagating flames. About 100μs must elapse before any difference can be detected between the flame kernels which will propagate and those which subsequently degenerate. The critical radius, at which this difference becomes apparent, has been measured in various mixtures of methane and air. The time to reach this critical stage has been determined. The flame speed has been calculated and after assuming a value for the final flame temperature, the burning velocity has been estimated. From the results obtained it has been possible to outline the mode of growth of the flame and to state which conditions favour ignition.

A network may be produced to describe the activities leading to a desired objective and subsequently analysed to set time limits for each activity. The application of network analysis to undergraduate and postgraduate physics courses is discussed.

The sources desCrIbed ore powered by small capaCllors ar shart transmlssian lines. Light flashes have been abtained whIch have half-peak duratIons of 8 to 50 nanoseconds. Energies greater than one-tenth of a Jaule have been dIscharged. Facwrs influencing flash duratIon are discussed.

The intensity and phase of a wave scattered by a cylindrical plasma column have been computed for the case where R/λf is near unity. The angular distribution of intensity was measured when a 9.6‐GHz plane wave was incident on a plasma of 2.68‐cm radius with the electric vector parallel to the cylinder axis. The variation of phase with angular position was also determined. A resonance was observed.

The rate of coagulation of an aerosol was calculated by Smoluchowski on the assumption that every collision resulted in the coalescence of two particles. The coagulation rate when there is a potential barrier round the aerosol particles is now calculated and two examples are considered.

An investigation of a conical z-pinch plasma gun, using a high speed camera and magnetic probes, has shown that a conical current sheet implodes to form a highly luminous axial pinch. The plasma and the current sheet at the muzzle of the gun are always symmetrical about the axis. The interaction between the azimuthal magnetic field and the current sheet ejects a plasma blob containing more than 10% of the injected gas. The conversion efficiency of capacitor energy into flow energy is 3%. A second, slower, plasma blob is also ejected.

A dispersion relation is produced for ultra high frequency drift waves arising from an electron stream drifting through a density gradient in a plasma. Plasma stability is discussed.

A batch processing autocorrelator is described suited to the analysis of stationary signals whether continuous or discontinuous in time. Input signal frequency may extend up to 75 MHz.

A compact, flexible light source is described, operable at wavelengths from the visible to vacuum ultraviolet or below. It consists of a plasma produced by the ablation of a solid dielectric surface in the presence of an intense electric discharge. By modifying the control circuitry, stable radiant discharges of duration ranging from under 1 mu s to over 10 mu s and of variable spectral quality may be produced, having application in high-speed photography, plasma diagnostics, absorption spectroscopy and biological irradiation.

Recent evidence suggests that memory representations of familiar faces may exaggerate distinctive information as do caricatures (G. Rhodes, S. Brennan, & S. Carey, Cognitive Psychology, 1987). Therefore caricatures should be effective representations of faces and should yield a right hemisphere processing advantage, as do photographs of faces. Photographs and caricatures of famous faces were presented to the left visual (LVF), the right visual field (RVF), and centrally (CVF), in a name-face verification task. There was a LVF (right hemisphere) advantage for both caricatures and photographs on name-face mismatches but no VF difference for matches. These results were true for both accuracy and reaction time. Processing strategy differences that may account for the difference between matches and mismatches are discussed. Performance was generally better for photographs than for caricatures, irrespective of visual field condition.

Jets or jet-like structures have been observed in laser produced plasmas for the past few years1–3. The understanding of such phenomena is of great importance where parameters such as symmetrical and stable implosion are required to achieve inertially confined fusion4.

IT has been suggested1–3 that ball lightning consists4 of a plasma vortex ring, but an appropriate mechanism for the formation of this plasma configuration at the time of a lightning discharge has yet to be proposed. A vortex ring in a fluid may be produced by the application of an asymmetric impulse; the detonation of an explosive on a flat surface, for example, sometimes produces smoke rings. I suggest that ball lightning may be produced by a process similar to the ablation of a solid surface by a high power laser pulse.

Estimates of a plasma temperature, electrical conductivity, and torch efficiency have been made from simple measurements made on the plasma and on the rf supply. Measurements were made with the aid of a simple magnetic probe and a pickup coil. Estimates are also made of the heating‐coil constants.

BALL lightning has been observed on many occasions, but there have been few events1–5 which have provided evidence with which to test any of the available explanations of the phenomenon. Consequently considerable weight has been placed on the “tub of water” event1. The occurrence reported by Stenhoff6 has presented unique evidence which enables us to carry out a number of simple calculations. The lady concerned describes the fireball appearing 39–40″ above the floor, then dropping 2 or 3″ when she tried to stop it with her hand. It was apparent for ∼1 s and had a diameter of ∼4″ but also had a halo.

The switch described may be inserted into a strip transmission line. Under the conditions investigated, it has an inductance of 10 nH and a resistance of 14 mω. Low jitter triggering is achieved with a 40 kv pulse rising in about 50 nsec.

A demountable Langmuir probe is built from commercially available glass components. The motion of a plastic cap on a glass thread allows single or double electrode systems to be positioned accurately in a discharge tube.

The authors describe their method of constructing a zone plate and suggest that it can be used in X-ray, ultraviolet and infrared regions where conventional lenses are completely absorbent.

THE phenomena described in this communication differ in some respects from those observed in other experiments with light duty contacts1,2 and the differences are attributed to the low reactance of the circuit and the presence of oxide coatings on the contact surfaces. The influence of such coatings on the electrical breakdown of a gap have been reported3, but the effects on switching phenomena are less well known.

It is shown that the low intensity radiation produced by phosphorescence of the envelope may be eliminated by using high purity fused silica.

I read the article entitled 'The PhD thesis in physics' by Profs H Lipson and A C Rose-Innes in the September issue of Physics Bulletin with interest, but found it based on rather narrow premises. In recommending theses to be confined to around 50 pages, their chief concern seems to be to facilitate the work of the external examiner.