Surface instability of a current-carrying plasma under the influence of a high-frequency electric-field

Surface instability of a collisionless semi-infinite current carrying plasma is studied. The semi-infinite plasma bounded by a plane surface is under the influence of a high frequency (hf) field. There are two classes of surface modes. One is a normal extension of zero high frequency field and the other due entirely to the presence ofhf field. As expected, with the increase in thehf field, the growth rates of the surface instabilities decrease. There are regions defined by the electron drift velocityu where the unstable surface and bulk regions overlap. The interesting result is that unlike the bulk plasma, there is a stable region on theu-axis flanked by two unstable regions. The width of this stable region increases with the increase in the field strength.

Mechanical testing of internal fixation devices: A theoretical and practical examination of current methods

Successful healing of long bone fractures is dependent on the mechanical environment created within the fracture, which in turn is dependent on the fixation strategy. Recent literature reports have suggested that locked plating devices are too stiff to reliably promote healing. However, in vitro testing of these devices has been inconsistent in both method of constraint and reported outcomes, making comparisons between studies and the assessment of construct stiffness problematic. Each of the methods previously used in the literature were assessed for their effect on the bending of the sample and concordant stiffness. The choice of outcome measures used in in vitro fracture studies was also assessed. Mechanical testing was conducted on seven hole locked plated constructs in each method for comparison. Based on the assessment of each method the use of spherical bearings, ball joints or similar is suggested at both ends of the sample. The use of near and far cortex movement was found to be more comprehensive and more accurate than traditional centrally calculated inter fragmentary movement values; stiffness was found to be highly susceptible to the accuracy of deformation measurements and constraint method, and should only be used as a within study comparison method. The reported stiffness values of locked plate constructs from in vitro mechanical testing is highly susceptible to testing constraints and output measures, with many standard techniques overestimating the stiffness of the construct. This raises the need for further investigation into the actual mechanical behaviour within the fracture gap of these devices.

Exact, self-similar, time-dependent free surface flows under gravity

A class of exact, self-similar, time-dependent solutions describing free surface flows under gravity is found which extends the self-propagating class of solutions discovered earlier by Freeman (1972) to those which decay with time.

Demonstration reaches: Looking back whilst moving forward with river rehabilitation under the Native Fish Strategy

‘Demonstration reaches’ are sections of river where multiple threats to native fish are addressed through river rehabilitation and strong community participation. They are an important way of promoting the key driving actions of the Murray-Darling Basin Authority's Native Fish Strategy (NFS) by using on-ground community-driven rehabilitation. Measuring rehabilitation success against well-defined targets and using this information to adaptively mange activities is fundamental to the demonstration reach philosophy. Seven years on from the establishment of the first demonstration reach, there are now seven throughout the Murray-Darling Basin (MDB), all in differing states of maturation and but all applying a standardised framework for monitoring native fish outcomes. In this study, we reflect on the role that demonstration reaches have played within the NFS, synthesise some key findings from 32 monitoring and evaluation outputs, and highlight some of the successes and barriers to success. We make recommendations as to how to strengthen the demonstration reach model to ensure it remains a relevant approach for fish habitat rehabilitation beyond the NFS and MDB.

Field evaluation of transgenic pineapple (Ananas comosus (L.) Merr.) cv. ‘Smooth Cayenne’ for resistance to blackheart under subtropical conditions

A comparative analysis of transgenic pineapple lines transformed with a polyphenol oxidase (PPO) gene (ppo) and the untransformed cultivar ‘Smooth Cayenne’ was made from plants grown in a series of field trials under cool subtropical conditions in southeast Queensland. In the four field trials where blackheart was recorded, all of the control lines expressed blackheart on each occasion and exhibited the greatest incidence (50%) and severity (34%) of symptoms. Irrespective of the gene transfer method or the gene construct used, 38% of the lines produced were regarded as blackheart resistant, having no blackheart symptoms in two or more trials. Five blackheart resistant transgenic lines consistently performed as well as or better than control plants in terms of fruit characteristics and quality.

Jerusalem Under Snow

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Vision under mesopic and scotopic illumination

Evidence has accumulated that rod activation under mesopic and scotopic light levels alters visual perception and performance. Here we review the most recent developments in the measurement of rod and cone contributions to mesopic color perception and temporal processing, with a focus on data measured using the four-primary photostimulator method that independently controls rod and cone excitations. We discuss the findings in the context of rod inputs to the three primary retinogeniculate pathways to understand rod contributions to mesopic vision. Additionally, we present evidence that hue perception is possible under scotopic, pure rod-mediated conditions that involves cortical mechanisms.

The Productivity of Strawberry Plants Growing Under Plastic High Tunnels in a Wet Subtropical Environment

The effect of plastic high tunnels on the performance of two strawberry (Fragaria ×ananassa) cultivars (Festival and Rubygem) and two breeding lines was studied in southeastern Queensland, Australia, over 2 years. Production in this area is affected by rain, with direct damage to the fruit and the development of fruit disease before harvest. The main objective of the study was to determine whether plants growing under tunnels had less rain damage, a lower incidence of disease, and higher yields than plants growing outdoors. Plants growing under the tunnels or outdoors had at best only small differences in leaf, crown, root, and flower and immature fruit dry weight. These responses were associated with relatively similar temperatures and relative humidities in the two growing environments. Marketable yields were 38% higher under the tunnels compared with yields outdoors in year 1, and 24% higher in year 2, mainly due to less rain damage. There were only small differences in the incidences of grey mold (Botrytis cinerea) and small and misshaped fruit in the plants growing under the tunnels and outdoors. There were also only small differences in postharvest quality, total soluble solids, and titratable acidity between the two environments. These results highlight the potential of plastic high tunnels for strawberry plants growing in subtropical areas that receive significant rainfall during the production season.

Freeze-drying of ovalbumin loaded mesoporous silica nanoparticle vaccine formulation increases antigen stability under ambient conditions

Amino functionalised mesoporous silica nanoparticles (AM-41) have been identified as a promising vaccine delivery material. The capacity of AM-41 to stabilise vaccine components at ambient temperature (23–27 °C) was determined by adsorbing the model antigen ovalbumin (OVA) to AM-41 particles (OVA-41). The OVA-41 was successfully freeze-dried using the excipients 5% trehalose and 1% PEG8000. Both the immunological activity of OVA and the nanoparticle structure were maintained following two months storage at ambient temperature. The results of immunisation studies in mice with reconstituted OVA-41 demonstrated the induction of humoral and cell-meditated immune responses. The capacity of AM-41 particles to facilitate ambient storage of vaccine components without loss of immunological potency will underpin the further development of this promising vaccine delivery platform.

Under Swastika and the French flag.

The memoirs were originally written for the Harvard University competition in 1940 and were translated by the author in 2001. Reflections on his childhood in Germany and Austria. His parents were both from Poland. They moved to Vienna in 1921, where his father opened a haberdashery store in the Second district (Leopoldstadt). Otto attended primary school in Czerningasse. Birth of his sister Cecile in 1924. After his failing business endeavors his father decided to move back to Germany, where the family opened a department store in Elbing, East Prussia. Otto attended Gymnasium, where he was one of only two Jewish students in his class. Growing Nazi movement among students. Summer vacations on the Baltic Sea. Private piano lessons. Hitler’s rise in Germany and life under National Socialism. Bar mitzvah in 1933. Anti-Jewish boycotts. His father fled to Vienna in order to escape a rounding up of Jews. The family followed soon after to Austria. Otto attended Gymnasium in the Zirkusgasse and started to work as a tutor. Member of a youth group and hiking tours in the mountains. Recollections of the Anschluss in 1938. Fervent attempts to obtain an exit visa for the United States, where they had a relative in New York. Description of discriminations and frequent attacks on Jewish friends and relatives in the weeks after the Anschluss. Otto was picked up by Nazi stormtroops. He was forced to hold up an anti-Jewish sign and was walked up and down, receiving beatings and spittings in front of a jeering crowd. Detailed account of the atmosphere within the Jewish population. The Gymnasium Zirkusgasse was transferred into a Jewish school. Frequent attacks of Hitler Youths on the students. Preparations for the “Matura” despite the turmoil. In June of 1938 his father was arrested and sent to Dachau concentration camp. After passing the final exams, Otto planned on leaving the country illegally, since he was subject to the Polish quota for the United States with

A unified approach to the solution of plane problems of Magneto-elasticity with special reference to a hole in a thin infinite conducting plate

Under certain specific assumption it has been observed that the basic equations of magneto-elasticity in the case of plane deformation lead to a biharmonic equation, as in the case of the classical plane theory of elasticity. The method of solving boundary value problems has been properly modified and a unified approach in solving such problems has been suggested with special reference to problems relating thin infinite plates with a hole. Closed form expressions have been obtained for the stresses due to a uniform magnetic field present in the plane of deformation of a thin infinite conducting plate with a circular hole, the plate being deformed by a tension acting parallel to the direction of the magnetic field.

Plastic response of orthotropic spherical shells under blast loading

The plastic response of a segment of a simply supported orthotropic spherical shell under a uniform blast loading applied on the convex surface of the shell is presented. The blast is assumed to impart a uniform velocity to the shell surface initially. The material of the shell is orthotropic obeying a modified Tresca yield hypersurface conditions and the associated flow rules. The deformation of the shell is determined during all phases of its motion by considering the motion of plastic hinges in different regimes of flow. Numerical results presented include the permanent deformed configuration of the shell and the total time of shell response for different degrees of orthotropy. Conclusions regarding the plastic behaviour of spherical shells with circumferential and meridional stiffening under uniform blast load are presented.

Influence of Band Non-Parabolicity on Few Ballistic Properties of III-V Quantum Wire Field Effect Transistors Under Strong Inversion

A simplified yet analytical approach on few ballistic properties of III-V quantum wire transistor has been presented by considering the band non-parabolicity of the electrons in accordance with Kane's energy band model using the Bohr-Sommerfeld's technique. The confinement of the electrons in the vertical and lateral directions are modeled by an infinite triangular and square well potentials respectively, giving rise to a two dimensional electron confinement. It has been shown that the quantum gate capacitance, the drain currents and the channel conductance in such systems are oscillatory functions of the applied gate and drain voltages at the strong inversion regime. The formation of subbands due to the electrical and structural quantization leads to the discreetness in the characteristics of such 1D ballistic transistors. A comparison has also been sought out between the self-consistent solution of the Poisson's-Schrodinger's equations using numerical techniques and analytical results using Bohr-Sommerfeld's method. The results as derived in this paper for all the energy band models gets simplified to the well known results under certain limiting conditions which forms the mathematical compatibility of our generalized theoretical formalism.