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A dense array of nanocolumns composed of GaAs‐InAs jointed whiskers and SiO2 covers has been fabricated on InAs substrates. The cylindrical GaAs whisker with a 20 nm diameter and 1.5 μm long is jointed on top of 0.3‐μm‐long InAs whisker by vapor‐liquid‐solid epitaxy. The nanocolumns array exhibited photoluminescence at 14 K.

In the past decade, Earth scientists have recognized the seismic hazards that crustal faults and sedimentary basins pose to Seattle, Washington (Figure 1). In 1998, the US. Geological Survey and its collaborators initiated a series of urban seismic studies of the upper crust to better map seismogenic structures and sedimentary basins in the Puget Lowland. These studies are called the Seismic Hazard Investigations of Puget Sound (SHIPS). In March 1998, we conducted our first SHIPS study, an investigation of the upper crustal structure of the Puget Lowland, using marine airgun sources and land recorders [Fisher et al., 1999].The study was nicknamed Wet SHIPS. In September 1999, we obtained a seismic refraction line to study the upper crustal structure in the Seattle area in a land-based study nicknamed Dry SHIPS [Brocher et al., 2000] (Figure 1). In March 2000, we recorded the demolition of the Seattle Kingdome sports stadium using a dense array of seismic recorders for a detailed site response study; this study was nicknamed Kingdome SHIPS (Figure 1).

The importance of the functional flexibility of the light-harvesting complexes of photo-system II (LHCII) in accommodating the fluctuation in the balance between light input and metabolic capacity in plants is emphasised. This flexibility is provided for by a relatively complex assembly of protein subunits, the interactions between them being controlled by protonation, xanthophyll de-epoxidation and phosphorylation. It is suggested that the 3-dimensional order imposed upon this assembly of proteins by the grana is a vital aspect of the modulation of LHCII function. Grana establish the LHCII conformation needed for efficient light harvesting and help prevent the dense array of proteins from collapsing into a highly dissipative state. The grana then allow a controlled development of non-photochemical quenching under the driving force of violaxanthin de-epoxidation and protonation. In plants grown under different irradiances the different grana content and xanthophyll cycle pool size together allow maximum quantum yield in limiting light and an appropriate level of non-photochemical quenching in excess light.

The importance of the functional flexibility of the light-harvesting complexes of photo-system II (LHCII) in accommodating the fluctuation in the balance between light input and metabolic capacity in plants is emphasised. This flexibility is provided for by a relatively complex assembly of protein subunits, the interactions between them being controlled by protonation, xanthophyll de-epoxidation and phosphorylation. It is suggested that the 3-dimensional order imposed upon this assembly of proteins by the grana is a vital aspect of the modulation of LHCII function. Grana establish the LHCII conformation needed for efficient light harvesting and help prevent the dense array of proteins from collapsing into a highly dissipative state. The grana then allow a controlled development of non-photochemical quenching under the driving force of violaxanthin de-epoxidation and protonation. In plants grown under different irradiances the different grana content and xanthophyll cycle pool size together allow maximum quantum yield in limiting light and an appropriate level of non-photochemical quenching in excess light.

AlGaAs-GaAs diode lasers with the active region based on a dense array of self-organised InAlAs-InAs quantum dots have been fabricated with 3.5 W output power for both facets with a peak conversion efficiency of 45% in a 100 /spl mu/m-wide stripe with uncoated facets were obtained.

A high-accuracy position-sensitive photodetector (PSD) for integrated sensor systems is presented. A 2-axis PSD composed of a dense array of vertical phototransistors and two arrays of polysilicon resistors was implemented using standard CMOS technology. Test results show better resolution and linearity as compared to a high-quality conventional PSD.

The potential of scalar audiomagnetotellurics (AMT) for base‐metal exploration in Finland has been used on a trial basis since 1976. The behavior of the source fields changes depending upon the season and the weather. Techniques similar to reference stations have been applied. In the search for elongated conductors, an azimuth of the minimum apparent resistivity is taken at every station to utilize the E-polarized field. Nevertheless, there are severe restrictions as to where AMT can be applied reliably. The target should be highly conductive; it should be large or elongated; and there should be no other good conductors at shallow depth or manmade sources nearby. A practical depth limit seems to be 2 000 m when frequencies between 8 and 3 700 Hz are used. A one‐dimensional model is convenient for modeling sounding data, and the model can be theoretically extended to more complex structures. It is important to have a dense array of stations. Two reconnaissance surveys and three detailed cases demonstrate the unique character of the AMT method. Difficult though it has been to squeeze reliable facts out of the data, at times they have provided fascinating new information. The next step is to improve observation techniques with a more sophisticated measuring device.

The contour lines of horseradish peroxidase injection sites in the ventrobasal hypothalamus were distorted by the border between arcuate and ventromedial nuclei as well as between arcuate nucleus and median eminence. The dense array of tanycyte processes is assumed to isolate the arcuate nucleus from the neighboring territories by establishing a diffusional barrier surface.

Mass loss, optical transmittance and the microscopic erosion sequence have been monitored for polymethylmethacrylate exposed to a 2.54 cm h−1 rainfall of 1.8 mm diameter water drops at an impact velocity of 222 m sec−1. Initial drop impacts produced well-defined fracture patterns consisting of a circular area free of damage surrounded by an annulus containing a dense array of fine, short cracks together with a sparse distribution of deeper fractures initiated along surface scratches. Continued exposure to the rainfield produced crack grown and crack intersections at sites of fracture annuli overlap followed by crevice growth as these fracture systems were enlarged by a hydraulic penetration mechanism. An extensive network of subsurface fractures continued to be produced within the expanding cavities with longer exposures. The transient stress distributions generated during a water drop impact on polymethylmethacrylate are considered in terms of their potential for producing circumferential fractures.

An electronic device for detecting locomotor activity in the home cage of small animals is described. The system involves a dense array of infrared (IR) beams designed to function as switches and capable of penetrating plastic walls of standard rodent cages without operational decrement. The device is reasonably inexpensive, is simple to calibrate, can be used with groups of animals, may be used for extended periods without maintenance, and is reliable with different cages.

Dense arrays of three-component seismographs have been maintained in the Travale geothermal field during two periods of several weeks. The particular array configuration (20 stations on a 3 × 3 km area) was intended to allow a high horizontal resolution investigation of the field itself, by analysis of steep-incidence waves. Natural and artificial sources at 100 km distances provided phases reflected by deep crustal interfaces, from which differential attenuation factor estimates are obtained. Consequent signatures of the area around and within the productive field are discussed, with respect also to laboratory measurements on porous, fluid-filled rock samples.

Site-response experiments were performed 5 months after the MS = 7.8 central Chile earthquake of 3 March 1985 to identify amplification due to topography and geology.Topographical amplification at Canal Beagle, a subdivision of Viña del Mar, was hypothesized immediately after the main event, when extensive damage was observed on the ridges of Canal Beagle. Using frequency-dependent spectral ratios of aftershock data obtained from a temporarily established dense array, it is shown that there is substantial amplification of motions at the ridges of Canal Beagle. The data set constitutes the first such set depicting topographical amplification at a heavily populated region and correlates well with the damage distribution observed during the main event.Dense arrays established in Viña del Mar also yielded extensive data which are quantified to show that, in the range of frequencies of engineering interest, there was substantial amplification at different sites of different geological formations. To substantiate this, spectral ratios developed from the strong-motion records of the main event are used to show the extensive degree of amplification at an alluvial site as compared to a rock site. Similarly, spectral ratios developed from aftershocks recorded at comparable stations qualitatively confirm that the frequency ranges for which the amplification of motions occur are quite similar to those from strong-motion records. In case of weak motions, the denser arrays established temporarily as described herein can be used to identify the frequency ranges for which amplification occurs, to quantify the degree of frequency-dependent amplification and used in microzonation of closely spaced localities.

Arrival times of seismic waves propagated to a dense array (20 three-component seismometers on a 3 × 3 km area) from natural sources beneath the Travale field, have been analysed for lateral variations which can be related to the extent of the productive reservoir. Significant teleseismic delays between sites only a few hundred meters apart correlate with productive well R9. Spatial variation of both P and S travel arrival times from local earthquakes at the edge of the array and 4 km deep beneath the reservoir consistently delineate its lateral extent to the south and east as documented by drillholes.

To resolve the high unemployment rates in many Western European countries, the notion of labour market flexibility has been gaining favour with academics and policy‐makers. This article examines the notion of labour market flexibility in detail and assesses the extent to which it has been implemented in West Germany, Britain and France. It is argued that the most significant developments towards flexibility have occurred in Britain because of the Thatcher government's commitment to neo‐liberal economic policies and because the ‘voluntarist’ British industrial relations system does not represent a barrier to the pursuit of such a policy. By contrast, there has been only a partial incorporation of flexibility initiatives within Germany and France largely because no government in either country has been committed to a full neo‐liberal assault in the existing dense array of national industrial relations institutions, norms and legislation. The article also assesses the extent to which labour market flexibilit...

An approximation scheme has been developed for calculating the density of states and autocorrelation of independent electrons in a dense array of weak stationary scatterers. This method, which avoids the customary perturbation expansions in powers of the scattering potential, requires a knowledge only of the autocorrelation of the potential. Results are presented of calculations for liquid Na at various temperatures. Comparison is made with the experimentally observed resistivity and angular correlation in positron annihilation experiments.

Prediction analysis provides an efficient means of estimating errors in local earthquake hypocenter determinations using a dense array of seismometers. The standard errors of the hypocentral coordinates and the origin time due to random errors in the data and model parameters may be calculated rigorously for a least-squares hypocenter inversion procedure using arbitrary earth models. Contour maps of the estimated standard errors in the hypocenter parameters are plotted for two array configurations and for several earth models and event depths. These maps are useful in predicting the relative accuracy and difficulty of hypocenter location as a function of position in the array, and in selecting events with small relative error to be used in velocity-structure refinement in the vicinity of the array. In particular, the method may be used to provide a means of optimizing array geometry to provide maximum hypocenter control in specific target regions. Tests were made using hypothetical data with prescribed error distributions showing good agreement with the error analysis.

The plaque organs of Pyrops consist of elaborately folded, finely perforated cuticular areas, each associated with numerous bipolar sensory cells organised in groups. The proximal, mitochondrial region of each dendrite narrows to reveal a ciliary ultrastructure. The ciliary fibrils pass into a highly vesiculated region and beyond this are succeeded by a dense array of neurotubules. Peripherally the dendrites proliferate numerous fine branches from which finer filaments extend into the cuticular pores. The plaques are considered to be complex olfactory organs evolved from groups of sensilla basiconica.

The intrinsic birefringence of multiple-coiled DNA is computed in terms of an equally dense array of parallel DNA molecules. The birefringence for n times-coiled DNA molecules is given by [Formula: see text] where beta(o) = 0, beta(i) = tan(-1) (p(i)/2pir(i)), p(i) = period of the i(th) helix coil and r(i) = radius of i(th) helix coil. The formula is applied to two cases of helically coiled DNA in biological material and found to agree quantitatively with experimental results.

openaire: EC/H2020/736937/EU//M-CUBE Passive electromagnetic decoupling in a very dense array of resonant active dipoles is a challenging task. Here we consider the decoupling of three very closely located resonant dipoles by two similar passive dipoles. In the non-resonant case it is not reducible to the decoupling of two active dipoles by a passive one. However, in the present case when the active dipoles have the resonant length their approximate decoupling is really achievable in the same way for both dimer and trimer of active dipoles. We prove this fact analytically, verify numerically and validate experimentally. Decoupling allows one to use different elements of the array in both transmitting and receiving regimes simultaneously that can be treated in terms of an active metasurface.

The effective electrical conductivity σ is computed for a composite medium consisting of a dense cubic array of identical, perfectly conducting spheres imbedded in a medium of conductivity σ0. When f, the fractional volume occupied by the spheres, is near its maximum value π/6, the result is σ/σ0=−(π/2)log [(π/6)−f]+…,(π/6)−f≪1. This result exhibits the singularity of σ at f=π/6, when the spheres touch each other. The previous results of Maxwell, of Rayleigh and of Meredith and Tobias are not valid near the singularity and they fail to reveal it. For f=0.5161 our result yields σ/σ0=7.65, while the measurement of Meredith and Tobias yielded σ/σ0=7.6.For a medium containing a square array of perfectly conducting circular cylinders we obtain σ/σ0=π32/2[(π/4−f)]12+…,(π/4)−f≪1. This result agrees well with the numerical results of H. B. Keller and D. Sachs. We also prove that for any value of f, σ/σ0 for a medium containing a square array of nonconducting cylinders is the reciprocal of σ/σ0 for the same array ...

Climate being the result of many interconnected processes, it can hardly be understood without models which describe these various processes as quantitatively as possible and define the parameters which are relevant for climate studies. Among those, surface processes and therefore surface parameters are now recognized to be of great importance. Some examples are discussed in the first part, showing the great interest to measure the relevant parameters on a multi-year basis, over large areas with sufficiently dense array and on a stable basis, in order to monitor climate changes or to study the impact on climate of the modifications of some relevant parameters which are analysed. Since space observations from satellites fulfil these requirements, it is clear that they will become very soon a fundamental tool for climate studies. Unfortunately, as it is discussed in the second part, satellites do measure only spectral radiances at the top of the atmosphere and the determination of the relevant surface parameters (or fluxes) from these radiances still raises many problems which have to be solved, although many progresses have already been made. The aim of this paper is therefore to review and discuss these problems and the various ways they have been tackled until now. The first part is devoted to an overview of what needs to be measured and why, while the existing methods for determining the most important surface parameters from space observations are presented in the second part where a particular attention is given to the theoretical and experimental validations of these methods, their limits and the problems still to be solved.

This chapter discusses the monitoring of environmental pollution using airborne equipment. The ability to assess ambient air quality depends on the availability of appropriate sensors. The use of a dense array of sensors is a very expensive undertaking and only provides comparative information between sensors by interpolative techniques. In this context, application of remote sensors is recommended as being generally most appropriate for rapid measurement of a profile or an array of spots. The presence of sulfur dioxide in the atmosphere is well known. This tracer gas forms aerosols, and sulfuric acid at the higher air levels. Drops of sulfuric acid fall far away from the place of emittance and do harm to the health of people, animals, plants, and buildings in completely separate areas.

Have you ever stood by a flooded mountain stream? Pebbles and cobbles are probably being audibly carried over the bed. From the evidence of their frequent collisions amongst themselves and with debris stationary on the bed, these stones must lie in dense array close to the stream bottom, to form what is called the bedload. However, this load is most unlikely to be visible, on account of the turbidity of the water. The smaller and more uniformly dispersed particles which make the current turbid are evidently being transported in a different way than the stones keeping close to the bed. They constitute the suspended load of the stream (Ch. 7).

In 1928, FELIX BLOCH predicted, theoretically, that electrons in an ideally periodic crystal will move ballistically, in other words, freely without collisions, ignoring the periodic dense array of atoms that make the crystal. The underlying matrix of atoms determine the ultimate velocity the electrons can acquire and their #x2018;effective mass’ in the crystal.

Graphene is a promising material possessing features relevant to bioelectronics applications. Graphene microelectrodes (GMEAs), which are fabricated in a dense array on a flexible polyimide substrate, were investigated in this work for their performance via electrical impedance spectroscopy. Biocompatibility and suitability of the GMEAs for extracellular recordings were tested by measuring electrical activities from acute heart tissue and cardiac muscle cells. The recordings show encouraging signal-to-noise ratios of 65 ± 15 for heart tissue recordings and 20 ± 10 for HL-1 cells. Considering the low noise and excellent robustness of the devices, the sensor arrays are suitable for diverse and biologically relevant applications.

The disclosure is directed to process and apparatus for the removal, site preparation, and replacement of any single connector pin contained within a sizeable array of closely spaced very small connector pins on an electronic packaging structure (substrate or module) without causing deleterious metallurgical effects either to the remaining pins or the ceramic substrate.