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The sedimentary sequence of the Permian-Triassic transition period of the central German "Hessian Depression" is characterised by up to 50 m of red beds. These sediments gradationally evolved from the Late Permian marine evaporitic formations of the Zechstein and they contain in their lower part several tens of metres of silts and clays of a mud playa environment, the main part of which is the [former] "Bröckelschiefer" [i. e. the Ohre, Friesland, and Fulda formations of the Hessian Depression] (Zechstein, Upper Permian). The overlying Lower Buntsandstein Subgroup is interpreted as an extended sandy braided river system, which had filled the subsiding basin. Although the entire sedimentary sequence seems to be rather continuous, there is a very distinct break in the main drainage direction between the "Bröckelschiefer" [facies, upper Zechstein] and the Lower Buntsandstein: The sedimentation of the "Bröckelschiefer" is, due to west-east directed drainage processes, associated with alluvial fans along the western bounding Rhenish Massif, which carried the finer clastic materials over a very low relief. On the contrary, the Lower Buntsandstein Subgroup in the same basin is a remnant of a braid-plain-like fluvial system, draining the mountainous highs of the Bohemian Massif, the Vindelician High, and the Massif Central in a strictly northward direction. This break in the drainage system reveals a relatively important tectonic uplifting of the southern surrounding areas. [ABSTRACT FROM AUTHOR]

The execution of industrial projects is subject to uncertainties that cause deviations from the designated project schedules. Therefore, it is desired to generate robust schedules in the sense of being insensitive to project disruptions, such as deviations in activity durations. Beyond that, efficient schedules that offer high robustness at a low cost are preferred. This paper focuses on the discrete time-cost tradeoff problem and develops a new method for identifying and ranking efficient schedules. First, a large schedule pool with robust schedules is generated. Efficient schedules are then identified and ranked by applying data envelopment analysis (DEA) with a particular super-efficiency model. An extensive evaluation based on a project testbed and an example construction project shows that the proposed method finds and ranks efficient schedules, that can be suitably presented to a project manager for decision support. [ABSTRACT FROM AUTHOR]

In this paper, we consider the monitoring and control of industrial projects that are performed by executing different activities within a given time duration. Hereby, it is desired to apply project control to each activity in order to avoid unexpected deviations in the project cost, respecting that the amount and cost of project control needs to be limited. We model the general setting of industrial project control as an optimal control problem with the goal of maximizing the cost reduction (savings) when applying control, while meeting constraints on the control effort. We then prove that it is optimal to apply a constant control effort to each activity during a given time duration. Consequently, we show that the exact optimal control solution can be obtained by nonlinear programming. We illustrate our results by an application example from the construction industry. [ABSTRACT FROM AUTHOR]

A sol–gel transformation of liquid silica precursor to solid silica particles was carried out in a one-pot synthesis way, where a solution of styrene butadiene elastomer was present. The composites, thus produced, offered remarkable improvements of mechanical and dynamic mechanical performances compared to precipitated silica. The morphological analysis reveals that the alkoxy-based silica particles resemble a raspberry structure when the synthesis of the silica was carried out in the presence of polymer molecules and represent a much more open silica-network structure. However, in the absence of the polymer, the morphology of the silica particles is found to be different. It is envisaged that the special morphology of the in situ synthesized silica particles contributes to the superior reinforcement effects, which are associated with a strong silica–rubber interaction by rubber chains trapped inside the raspberry-like silica aggregates. Therefore, the interfaces are characterized in detail by low-field solid-state 1H NMR spectroscopy, 29Si solid-state NMR spectroscopy, and energy-dispersive X-ray spectroscopy. Low-field 1H NMR-based double-quantum experiments provide a quantitative information about the cross-link density of the silica-filled rubber composites and about the influence of silane coupling agent on the chemical cross-link density of the network and correlates well with equilibrium swelling measurements. The special microstructure of the alkoxy-based silica was found to be associated with the interaction between alkoxy-based silica and rubber chains as a consequence of particle growth in the presence of rubber chains. [ABSTRACT FROM AUTHOR]

Descriptions of three new species in the genus Bruchidius Schilsky, 1905 are presented. Bruchidius nepalensis sp. nov. from Nepal and B. tricolor sp. nov. from India, Laos and Thailand are assigned to the Bruchidius japonicus species-group, while B. planicornis sp. nov. from Iran and Turkey is assigned to the Bruchidius astragali species-group. Detailed fi gures of antennae and genitalia are given. [ABSTRACT FROM AUTHOR]

This paper investigates the effect of repeated time-limited input signals on the output excursion of stable, linear time-invariant systems. It is first shown that the maximum norm of the output signal remains bounded if the repeated input signals are separated by a nonzero dwell time. Then a novel method for computing a tight bound on the output signal norm is proposed. The setting of the paper is motivated by a vehicle platooning application, where vehicles repeatedly open/close gaps in order to perform lane changes. The developed method analyzes driving safety by computing a bound on the spacing error between vehicles when performing repeated open/close gap maneuvers. [ABSTRACT FROM AUTHOR]

Reconfigurable manufacturing systems(RMS) support flexibility in the product variety and the configuration of the manufacturing system itself in order to enable quick adjustments to new products and production requirements. As a consequence, an essential feature of RMS is their ability to rapidly modify the control strategy during run-time. In this paper, the particular problem of changing the specified operation of a RMS, whose logical behaviour is modelled as a finite state automaton, is addressed. The notion ofreconfigurability of specifications(RoS) is introduced and it is shown that the stated reconfiguration problem can be formulated as a controlled language convergence problem. In addition, algorithms for the verification of RoS and the construction of a reconfiguration supervisor are proposed. The supervisor is realised in a modular way which facilitates the extension by new configurations. Finally, it is shown that a supremal nonblocking and controllable strict subautomaton of the plant automaton that fulfils RoS exists in case RoS is violated for the plant automaton itself and an algorithm for the computation of this strict subautomaton is presented. The developed concepts and results are illustrated by a manufacturing cell example. [ABSTRACT FROM PUBLISHER]

Descriptions of three new species in the genus Bruchidius Schilsky, 1905 are presented. Bruchidius nepalensis sp. nov. from Nepal and B. tricolor sp. nov. from India, Laos and Thailand are assigned to the Bruchidius japonicus species-group, while B. planicornis sp. nov. from Iran and Turkey is assigned to the Bruchidius astragali species-group. Detailed figures of antennae and genitalia are given. [ABSTRACT FROM AUTHOR]

A simplified reactive blending method is investigated to blend effectively the nitrile butadiene rubber (NBR) and in-situ synthesized polyurethane–urea (PUU). The in-situ synthesis of PUU via the prepolymer route was realized in presence of NBR in an internal mixer at a reactive blending temperature of 100 °C that was determined from the chemo-rheological analysis of PUU reactive premix of 4,4′-diphenylmethane diisocyanate-terminated prepolymer and 1,3-phenylene diamine. The 1 H NMR spectroscopic analysis showed high conversion (∼87 ± 3%) of amino groups of 1,3-phenylene diamine during rapid in-situ addition polymerization with isocyanate groups of prepolymer. The peroxide-cured NBR/PUU blend vulcanizates exhibited remarkable improvements in cure characteristics, mechanical and dynamic-mechanical properties. The dynamic-mechanical analysis of blend vulcanizates demonstrated a concentration-dependent higher storage modulus ( E ′) and a lower loss factor (tan δ ) in a stable rubbery plateau region extending up to 180 °C. The improvement in performance characteristics of blend vulcanizates was attributed to the strong interfacial adhesion developed during the reactive blending process and was verified by SEM and energy filtered TEM measurements. [ABSTRACT FROM AUTHOR]

A substantial number of tasks in production systems are executed in a repetitive, cyclic fashion. Specifically, production systems run different production cycles of different products as well as different instances of the same production cycle. In this paper, we consider the optimal control and interleaving of such production cycles in a supervisory control framework for discrete event systems (DESs). That is, different from other approaches, our work is based on a behavioral specification of each production cycle. First, we adapt an optimal control approach for DESs, in order to optimize the operation of individual production cycles. Second, we employ the interleaving composition to design a supervisor that enables the simultaneous execution of different production cycles. Combining both results, we can further determine the maximum number of production cycles that can be executed simultaneously on a given production system. [ABSTRACT FROM AUTHOR]

Water pollution plus Bistrita River and crossing the river had a major negative impact on communities of aquatic organisms, particularly on fish communities. Sampling of biological material from sampling points and data processing have led to results on the overall environmental condition of the river Bistrita. Rich in species abundance and gives an indication of the specific degree of impairment of human impact aquatic ecosystems. By applying synthetic ecological indexes such as IBI and EFI +, put out both the level of damage in each sampling and classification of each river section in a given fishing zone. [ABSTRACT FROM AUTHOR]

Blends of nitrile butadiene rubber (NBR) and in-situ synthesized thermoplastic polyurethane-urea (PUU) are prepared by a reactive blending method. The PUU is synthesized in-situ from the polyaddition of 4,4′-diphenylmethane diisocyanate-terminated prepolymer with Bisaniline-M during blending with NBR in an internal mixer. The 1H NMR spectroscopic analysis shows up to 93% conversion of Bisaniline-M to PUU in NBR/PUU blends. The incorporation of PUU improves the tensile characteristic, tear and abrasion resistance however a temperature dependent softening of amorphous PUU phase diminishes the dynamic-mechanical behavior of blend vulcanizates. Improvement in physical properties of blends is attributed to good interfacial adhesion between dispersed PUU domains and continuous NBR matrix as seen by TEM. [ABSTRACT FROM AUTHOR]

To highlight the changes in the structure of fish communities through the advent of Bicaz lakes and Poiana Teiului samples were taken both from the two lakes, using trammel and the upstream river areas (Bistrita - Galu) and downstream (Bistrita - City Bicaz) them. The two lakes were identified higher valences species to environmental conditions and food (perch, bleak, chub) except nase identified Bicaz lake, which with the advent dam at Poiana Teiului, probably will not be able to migrate on the river, leading to the reduction and disappearance of the numbers of the lake. By sampling upstream and downstream, by calculating some ecological indices in the two collection points is apparent influence they have two lakes on the fish fauna of the river. Fish community structure is slightly modified in the upstream of the two lakes. Downstream river course due to strong fragmentation and water pollution, fish community structure is changed by the dominance resistant species with broad valences. [ABSTRACT FROM AUTHOR]

This paper tries to highlight the extent to which were affected fish communities on the Bistrita River tributaries in the upper basin. For this purpose samples were taken from 10 collection points both on tributaries of right and left of the Bistrita River. Sampling was done in the spring and summer when fish species are active foraging and reproduction. In each collection point were recorded a number of physico-chemical water parameters (temperature, conductivity, pH, amount of O2 dissolved in water), habitat status data (collected surface, water depth, speed, altitude and GPS coordinates) and raw data on fish samples (number of specimens per species and biomass). Through data processing and calculation of indices ecological, biodiversity index could highlight the current status of fish fauna, which was comparable to that existing before the human impact after 1960. By determining the IBI was revealed that the fish communities of the Bistrita river tributaries, upstream from Lake Bicaz, were the least affected, except tributary Neagra Şarului. [ABSTRACT FROM AUTHOR]

The automation of today's large-scale industrial systems relies on the operation of distributed controller devices that perform local computations and exchange information via communication networks. The subject of this paper is the development of a family of shared-medium industrial communication protocols that support the transmission of real-time (RT) and nonreal-time (nRT) data among distributed controller devices. Different from existing protocols, we suggest to incorporate information that is available from the control application in the protocol definition. As a result, our protocols dynamically change the bandwidth allocation on the shared medium according to the instantaneous communication requirements while ensuring hard RT guarantees. Following the recent developments in industrial automation, our protocols can be realized as software layers on top of low-cost conventional Ethernet. [ABSTRACT FROM AUTHOR]

This study reflects the current state of the fish fauna from the lower basin of river Bârlad, within the research started in 2003 in the hydrographic basin of this river regarding the inventorying of the species of fish from these waters. The lower basin and particularly the main course of river Bârlad have been seriously affected by water pollution, which led even to the extinction of the fish communities across the entire main course of the river, downstream of the city of Bârlad. This paper highlights the extent to which these fish communities have recovered, the data obtained being compared to that from 2003 and from the literature in order to identify the changes suffered by the structure of the fish communities. To this effect, investigations have been conducted in terms of species composition, the structure of fish assemblages, as well as the index of biological integrity (IBI) which best reflects the present condition of the fish stocks in these ecosystems. [ABSTRACT FROM AUTHOR]

Land-based high-frequency (HF) radars have the unique capability of continuously monitoring ocean surface environments at ranges up to 200 km off the coast. They provide reliable data on ocean surface currents and under slightly stricter conditions can also give information on ocean waves. Although extraction of wind direction is possible, estimation of wind speed poses a challenge. Existing methods estimate wind speed indirectly from the radar derived ocean wave spectrum, which is estimated from the second-order sidebands of the radar Doppler spectrum. The latter is extracted at shorter ranges compared with the first-order signal, thus limiting the method to short distances. Given this limitation, we explore the possibility of deriving wind speed from radar first-order backscatter signal. Two new methods are developed and presented that explore the relationship between wind speed and wave generation at the Bragg frequency matching that of the radar. One of the methods utilizes the absolute energy level of the radar first-order peaks while the second method uses the directional spreading of the wind generated waves at the Bragg frequency. For both methods, artificial neural network analysis is performed to derive the interdependence of the relevant parameters with wind speed. The first method is suitable for application only at single locations where in situ data are available and the network has been trained for while the second method can also be used outside of the training location on any point within the radar coverage area. Both methods require two or more radar sites and information on the radio beam direction. The methods are verified with data collected in Fedje, Norway, and the Ligurian Sea, Italy using beam forming HF WEllen RAdar (WERA) systems operated at 27.68 and 12.5 MHz, respectively. The results show that application of either method requires wind speeds above a minimum value (lower limit). This limit is radar frequency dependent and is 2.5 and 4.0 m/s for 27.68 and 12.5 MHz, respectively. In addition, an upper limit is identified which is caused by wave energy saturation at the Bragg wave frequency. Estimation of this limit took place through an evaluation of a year long database of ocean spectra generated by a numerical model (third generation WAM). It was found to be at 9.0 and 11.0 m/s for 27.68 and 12.5 MHz, respectively. Above this saturation limit, conventional second-order methods have to be applied, which at this range of wind speed no longer suffer from low signal-to-noise ratios. For use in operational systems, a hybrid of first- and second-order methods is recommended. [ABSTRACT FROM AUTHOR]

High-frequency (HF) surface wave radars provide the unique capability to continuously monitor the coastal environment far beyond the range of conventional microwave radars. Bragg-resonant backscattering by ocean waves with half the electromagnetic radar wavelength allows ocean surface currents to be measured at distances up to 200 km. When a tsunami propagates from the deep ocean to shallow water, a specific ocean current signature is generated throughout the water column. Due to the long range of an HF radar, it is possible to detect this current signature at the shelf edge. When the shelf edge is about 100 km in front of the coastline, the radar can detect the tsunami about 45 min before it hits the coast, leaving enough time to issue an early warning. As up to now no HF radar measurements of an approaching tsunami exist, a simulation study has been done to fix parameters like the required spatial resolution or the maximum coherent integration time allowed. The simulation involves several steps, starting with the Hamburg Shelf Ocean Model (HAMSOM) which is used to estimate the tsunami-induced current velocity at 1 km spatial resolution and 1 s time step. This ocean current signal is then superimposed to modelled and measured HF radar backscatter signals using a new modulation technique. After applying conventional HF radar signal processing techniques, the surface current maps contain the rapidly changing tsunami-induced current features, which can be compared to the HAMSOM data. The specific radial tsunami current signatures can clearly be observed in these maps, if appropriate spatial and temporal resolution is used. Based on the entropy of the ocean current maps, a tsunami detection algorithm is described which can be used to issue an automated tsunami warning message. [ABSTRACT FROM AUTHOR]

Tidal and wind-driven surface currents in the German Bight between shallow mudflats of the North Frisian islands and the island of Helgoland are studied using coastal high-frequency radar (HFR) observations and hindcasts from a primitive equation numerical model. The setup of the observational system is described, and estimates of expected measurement errors are given. A quantitative comparison of numerical model results and observations is performed. The dominant tidal components are extracted from the two data sources using tidal harmonic analysis and the corresponding tidal ellipses are defined. Results show that the spatial patterns of different tidal ellipse parameters are consistent in the two data sets. Model sensitivity studies with constant and variable salinity and temperature distributions are used to study density-related mechanisms of circulation. Furthermore, the role of the surface wind field in driving the German Bight circulation is investigated using the complex correlation between wind and surface current vectors. The observed change of the respective correlation patterns from the coastal to open ocean is shown to be due to a combination of density effects, the coastline and topography. The overall conclusion is that HFR observations resolve the small-scale and rapidly evolving characteristics of coastal currents well in the studied area and could present an important component for regional operational oceanography when combined with numerical modelling. Some unresolved issues associated with the complex circulation and large instability of circulation in front of the Elbe River Estuary justify further considerations of this area using dedicated surveys and modelling efforts. [ABSTRACT FROM AUTHOR]

Serum levels of S-100B and neurone-specific enolase (NSE) reflect cerebral injury in a variety of neurological conditions such as stroke, traumatic brain injury, and cardiac arrest. There are limited data on the release of S-100B and NSE following carotid artery stenting (CAS). In 22 patients undergoing CAS, serial blood samples for S-100B and NSE were collected before and 2, 4, and 6 to 8 hours after the procedure. A group of 20 patients with significant CAS undergoing purely diagnostic angiography served as controls. A significant increase in S-100B levels was observed 2 hours after the procedure in patients with CAS (P = .001) with a gradual decline over the next hours. In contrast, patients who underwent purely diagnostic angiography did not show significant changes in S-100B levels up to 8 hours after the procedure. Neither patients with CAS nor those undergoing diagnostic angiography displayed any significant changes in serial NSE levels. [ABSTRACT FROM AUTHOR]

Abstract: The effect of stearic acid on the properties of different rubbers/montmorillonite composites was studied. We used alkyl quaternary ammonium modified montmorillonite (organo-montmorillonite), which was additionally modified with stearic acid. Premixed with the montmorillonite, the stearic acid expanded the clay mineral layers, thus permitting the rubber molecules to be more easily intercalated into the montmorillonite. We used several kinds of rubbers with different polarities and molecular structures. Both the X-ray diffraction and infrared spectroscopy studies indicated that the stearic acid propped up interlayer space allowing the intercalation of the rubber chains. Measurement of the physical and dynamic mechanical properties, along with studies of the composite morphology by transmission electron microscopy, very clearly showed that mixing the montmorillonite clay with stearic acid yielded various rubber nanocomposites with a high amount of intercalated and exfoliated montmorillonite particles. Either complete intercalation or increased nanostructure formation yielded as compared to the standard rubber–clay mineral composites prepared with a normal dose (2 parts per hundred of rubber) of stearic acid, can be achieved by adding a large amount of stearic acid (10 parts per hundred of rubber in our case) to non-polar rubbers (e.g. natural rubber (NR), ethylene propylene rubber (EPDM), etc.) that are not known to form totally exfoliated structures by simple melt mixing of montmorillonite and rubber. [ABSTRACT FROM AUTHOR]

Abstract: Reinforcing fillers are added to elastomeric compounds to improve and adjust several mechanical, dynamical, tribological, etc. properties with respect to different applications, i.e. for automotive tires, or technical rubber goods. Carbon black and precipitated silica are widely used as rubber reinforcing fillers; however, some new classes of nanosized substances like organophilic modified clay or carbon nanotubes are presently intensive studied as possible future filler systems in combination with carbon black or silica. An important parameter for the dispersibility and compatibility of the filler in the polymer matrix of rubber compounds is the surface energy and surface polarity of the solid filler particles. Therefore, we systematically measured and compared the dynamic contact angles of a collection of different filler types (carbon blacks, silica, carbon nanotubes and organoclays) using the Wilhelmy method, whereby the particles were fixed as a thin layer at a double-sided adhesive tape. From the contact angle values the polar and disperse part of the surface energies of the filler particles were calculated by fitting Fowkes formula. For an estimation of the compatibility of the fillers with different types of rubber polymers we additionally analyzed the surface energy and polarity of the gum (unfilled) elastomers. From the evaluated surface energies and polarities, thermodynamic predictors for the dispersibility (enthalpy of immersion), the adhesion between filler particles and polymer matrix in the nanocomposite, and for the flocculation behaviour of the particles in a rubber matrix (difference in the works of adhesion) were derived. These thermodynamic predictors improve considerably the compounding process of novel rubber nanocomposites with respect to target-oriented adjustment of rubber properties. [Copyright &y& Elsevier]

Abstract: Maya Blue, a pigment composed of very low concentrations of natural indigo and the clay mineral palygorskite, is one of the most brilliant blue dyes, intensively used for more than 2000 years in Mesoamerica. It is extremely stable against environmental attacks and was applied by the Indians for inside and outside mural paintings, ceramics, textiles and for colouring their famous codices. In the present paper it was studied as a powder (compared with modern synthetic indigo) and as colour on tissues, a Maya clay head, and fragment IV of the famous Codex Huamantla. Investigations using Raman spectroscopy in the visible and near-infrared range showed a high degree of correspondence among all Maya Blue-carrying samples and a good agreement with synthetic indigo. Additional spectral lines may be explained by a transformation of the planar indigo molecule when binding to the palygorskite lattice. Thermal investigations of the original “amatl” paper of the codex and of recent paper from fig-trees showed a high similarity and thus proved that this tree was chosen for paper making by Mayas, Aztecs and other Indian tribes. This was also true for the codex. [Copyright &y& Elsevier]

Experiments have been carried out in a model basin 16 × 1·2 × 0·9 m to address the effect of base-level and discharge changes on actively growing alluvial-shoreline wedges. Two distinct types of erosive surfaces were investigated: one produced by base-level fluctuations in the coastal zone and the other by discharge and supply fluctuations in the upstream alluvial basin. In the first experiment, three similar base-level cycles were simulated keeping sediment supply and basin tilting constant within each cycle, and changing discharge from one cycle to the next. In the second experiment, rises and falls of base level were instantaneous and discharge changes were in phase (high discharge linked to high water levels in the basin). In the third experiment, base level and discharge changed gradually, at different rates and they were out of phase, resembling a typical glacio-eustatic cycle in which sea-level rises and falls are linked to increased and decreased discharge, respectively. The resulting stratigraphy of the alluvial to deltaic sedimentary wedge was analysed in terms of the development of unconformities and the evolving depositional geometry. An intervening decoupled zone between parts of the model basin dominated by alluvial processes and that at the coastal zone is identified. Within this decoupled zone, unconformities in the alluvial succession tend to vanish basinward, and base-level generated coastal unconformities disappear landward. The two types of unconformity can be generated at different times during a glacio-eustatic cycle, and it is thus erroneous to correlate them, even though they may appear to form a continuous surface. Unconformities within the modelled stratigraphy do not constitute time lines nor do they consistently separate younger from older beds, as they require a significant time to form and they have thick sedimentary packages as depositional correlatives. The experiments also support a fourfold division of sequences, showing the development of a significant sedimentary package during base-level falls. [ABSTRACT FROM AUTHOR]

Objectives: This study sought to compare the efficacy of two different cerebral protection systems for the prevention of embolization during carotid artery stenting (CAS) using a transcranial Doppler (TCD) monitoring with the detection of microembolic signals (MES). Background: Despite the introduction of cerebral protection systems, neurologic complications during CAS cannot completely be prevented. Transcranial Doppler and detection of MES may aid in assessing the efficacy of different neuroprotection systems. Methods: A total of 42 patients with internal carotid artery stenoses were treated by CAS using either a filter (E.P.I. FilterWire, Boston Scientific Corp., Santa Clara, California) (n = 21) or a proximal endovascular clamping device (MO.MA system, Invatec s.r.l., Roncadelle, Italy) (n = 21). Microembolic signal counts were compared during five phases: placement of the protection device, passage of the stenosis, stent deployment, balloon dilation, and retrieval of the protection device. Results: There were no significant differences in clinical or angiographic outcomes between the two groups. Compared to the filter device, the MO.MA system significantly reduced MES counts during the procedural phases of wire passage of the stenosis, stent deployment, balloon dilation, and in total (MES counts for the filter device were 25 ± 22, 73 ± 49, 70 ± 31, and 196 ± 84 during the three phases and in total, MES counts for the MO.MA system were 1.8 ± 3.2, 11 ± 19, 12 ± 21, and 57 ± 41, respectively; p < 0.0001). Conclusions: In comparison to a filter device the MO.MA system led to significantly lower MES counts during CAS. The detection of MES by TCD may facilitate the evaluation and comparison of different neuroprotection systems. [Copyright &y& Elsevier]

Raman spectra of pure synthetic indigo and of Maya blue of a Mexican clay sculpture are compared. The Raman spectrum of Maya blue shows extra bands assigned to vibrational modes of Bu symmetry as well as an increasing intensity of some other bands. The partial removal of the mutual exclusion rule for the centrosymmetric indigo molecule is supposed to indicate a loss of its planarity due to strong adsorption at the palygorscite matrix. [Copyright &y& Elsevier]

We present a passive method for reducing the size of a focal spot blurred by wavefront distortions in an optical system. The key to this reduction lies in the rather unique behavior of photonic crystals to exhibit negative refraction. First, we review the design of such a photonic crystal structure and analyze its dispersion property to find the proper condition where negative refraction occurs. The predictions derived from theoretical infinite structures are confirmed by rigorous electromagnetic analysis using both the finite-difference time-domain (FDTD) and rigorous coupled wave analysis (RCWA) methods in combination with more realistic finite structure. Second, we discuss an unconventional approach to exploit the negative refractive behavior in reducing the focal spot area spread caused by a blurred wavefront. A proof-of-principle calculation of this approach is performed with the ray trace method to visualize the reduction of the illumination area while preserving the propagation angle of the incoming beam. Finally, we investigate the crystal's performance when its two-dimensional structure is exposed to conical illumination. [ABSTRACT FROM AUTHOR]

The interaction of nanosecond laser pulses in the ultraviolet wavelength range and femtosecond laser pulses in the near-infrared region with the semiconductor SiC and the composite compound SiC–TiC–TiB2 was investigated. Surface analytical techniques, such as XPS, depth profile (DP), and micro-Raman spectroscopy (μ-RS) were used to identify the chemical changes between untreated and laser-treated areas. Single-pulse irradiation led to material modifications in the condensed state in most instances. Multi-pulse results differed depending on the pulse duration. Crystal structure changes were observed as a consequence of laser-induced melting and resolidification. In air contact all components underwent oxidation reactions according to thermodynamic expectations. Exceptions were observed under exclusion of oxygen, SiC was reduced to elemental Si. [Copyright &y& Elsevier]

ABSTRACT The dynamics between sediment erosion and accumulation at an alluvial basin margin affected by changes in the surface hydrology are explored using scaled analogue models produced in a flume. The presented results differ from previous counterparts in that accumulation or erosion has not been forced at a spreading outlet, but occurred at a slope change produced by previously accumulated sediment. Cyclical upstream incision produced by increased stream discharge generated incised valleys, and these were subsequently filled by sediment carried by less efficient streams generated during the low discharge period. High resolution mapping using 2.5 mm contour maps allowed the study of sediment accumulation and terrain modelling. The results of three selected experiments are analysed. The only variable explored was discharge. The basin margin was simulated by a ramp inserted in a low sloping flume, consisting of two segments of different slopes selected to emulate high and low efficiency flume fans produced elsewhere. Water and fine-medium sand entered the ramp along a narrow (0.1 m) channel and flow expanded but without occupying the complete 1.2 m flume width. Flows were highly concentrated and noncohesive. Fan-like accumulation (slope: 0.11) began during low discharge (LD) periods at the ramp slope break, and proceeded upstream, onlapping quickly at first, but shifting to mostly progradation at the end of the period. High discharges (HD) usually generated two or three incised channels at the beginning of the period, but one of them prevailed and rapidly eroded parts of the LD fan and moved the sediment to a more distal low-sloping fan (slope: 0.045). Both LD and HD fans passed downstream into a system of small parallel channels resembling a braided alluvial plain ending in sediment lobes. The mapping of the accumulated sediment during the various periods allowed calculation of sediment budgets for the entire flume. The stratal architecture of the deposits was... [ABSTRACT FROM AUTHOR]

Transferred nuclear Overhauser enhancement (trNOE) experiments have been performed to study the bioactive conformation(s) of Ro09-3472/000 derivatives in the ternary complex with Candida albicans myristoyl-CoA: protein N-myristoyltransferase (CaNmt) and myristoylCoA (MyrCoA). A critical step in the trNOE study is to identify ‘true’ trNOEs in the spectra. Nonspecific binding of ligands to target proteins and/or spin diffusion effects can give rise to ‘false’ trNOEs, which may lead to an incorrect conclusion if used to derive bound conformations. In this study for all ligands the observed trNOEs arose from specific binding interactions with the active site of CaNmt. This was shown by displacing the ligand with the known tightly binding active-site inhibitor 1 [Devadas, B., Zupec, M.E., Freeman, S.K., Brown, D.L., Nagarajan, S., Sikorski, J.A., McWherter, C.A., Getman, D. P. & Gordon, J.I. (1995) J. Med. Chem. 38, 1837–1840] and measuring the resonance linewidths in the NMR spectrum before and after addition of the competitive inhibitor. The compounds were also tested for nonspecific protein binding with bovine serum albumin (BSA) using the same method. Of the six compounds tested, Ro09-3700/001 (racemate) and its optically pure enantiomers, Ro09-4764/001(S) and Ro09-4765/001(R), showed both specific binding to CaNmt and no interaction with BSA. The NMR data of these molecules in the ternary complex with CaNmt/MyrCoA could thus be used for a detailed structural analysis. Thereby, the conformation of the bound ligand was obtained from a conformational search using the observed trNOEs as a selection filter. The NMR-determined conformations are in good agreement with the recently solved CaNmt-bound X-ray structures of two similar Ro09-3472/000 derivatives. [ABSTRACT FROM AUTHOR]

Examines the near-field intensity distributions and associated illumination efficiencies of Talbot array illuminators. Details on the design and working principles of Talbot array illuminator; Result of analysis of near-field intensity distribution and illumination efficiency; Conclusion.

Avionics Full-Duplex Switched Ethernet (AFDX) is a fault-tolerant real-time communication bus for safety–critical applications in aircraft. AFDX configures communication channels, denoted as virtual links (VLs), ensuring bounded message delays through traffic shaping at both end-systems and switches. Effective AFDX network design necessitates computing the worst-case end-to-end delay of time-critical VLs to meet specified message deadlines. This paper presents a new method for calculating tight bounds on the worst-case end-to-end delay for each VL in an AFDX network. We introduce the new notion of an extended uninterrupted transmission interval, which is the prerequisite for computing the worst-case queuing delay at switches. Adding up these queuing delays along the path of each VL between end-systems yields a tight upper bound on the worst-case end-to-end delay. The correctness of our results is formally proved, and comprehensive simulation experiments on different example networks confirm the tightness of our bound. These simulations also demonstrate the superior performance of our method compared to existing approaches that offer more pessimistic as well as optimistic results. [ABSTRACT FROM AUTHOR]

Investigates the nuclear magnetic resonance (NMR) spectroscopy and secondary structure of domains I and II of rat brain calbindin D[sub28k], a calcium-binding protein. Location of the high-affinity sites; Application of a series of heteronuclear 2D, 3D and 4D high-resolutions NMR experiments; Construction of a structural model of calb I-II.

The distal swellings of growing flagella in spermatocytes of Ephestia kuehniella Z. contain dense material associated with the ends of axonemal microtubules. In order to define the nature of this material, spermatocytes were lysed under microtubule-stabilizing conditions, spun onto cover-slips, probed with an antibody against β-tubulin and processed for indirect immunofluorescence. Whereas the dense material was lost from the cells when untreated spermatocytes were used, a block of stained material was visible in cold-treated spermatocytes. Most probably, cold-treatment alters the dense material and guarantees its survival during preparation of the cells for anti-tubulin immunofluorescence. The positive reaction with the antibody indicates the presence of β-tubulin. Flagellar outgrowth in spermatogenesis of the moth starts in late prophase I and continues throughout both meiotic divisions. Therefore, spindles and flagella compete for tubulin monomers. A tubulin reserve, deposited early in development at the elongating tip of axonemes. may ensure their uninterrupted growth, independent of tubulin-consuming cytoplasmic events. In order to test this hypothesis, flagellar outgrowth was studied in the spermatocytes of a long-homed beetle. Agapanthia villosoviridescens de Geer (Cerambycidae, Coleoptera) using electron microscopy. In this species, flagella begin to elongate only in telophase II, when the second meiotic spindle is just disassembling. The absence of dense material at the tip of flagellar stubs in the beetle corroborates the hypothesis formulated above. [ABSTRACT FROM AUTHOR]

Spermatogonia and both generations of spermatocytes of Tenebrio molitor possess conventional bipolar spindles with only few aster MTs. Spindles in metaphase spermatogonia are surrounded by fenestrated two-layered cisternae and do not contain intraspindle membranes. In metaphase spermatocytes. a spindle envelope is missing, but intraspindle membranes are abundant. Mitochondria form long threads lateral to the nucleus in prophase I of meiosis. The elongated mitochondria also align parallel to the spindle apparatus in prometaphase I, As a consequence, the spindles reside in a cage formed of mitochondria. This arrangement may guarantee proper bisection of the chondriome during division. Cells are tightly packed during spermatogonial divisions and in prophase I, but large intercellular spaces develop when the first meiotic spindle assembles. Then, cytoplasmic bridges which persist between the cells as a result of incomplete cytokinesis appear as slender tubes, Anti-tubulin immunofluorescence using an antibody against acetylated α-tubulin revealed intense acetylation throughout spermatogonial mitosis but a low degree of α-tubulin acetylation in meiotic spindles prior to telophase. This may indicate a high microtubule turnover in meiosis. [ABSTRACT FROM AUTHOR]

Presents experimental results of an approach which allows one to operate a set of sonar sensors simultaneously. Discussion on the use of conventional time-of-flight (CTOF) sonar sensing in distinguishing objects; Experimental platform; Results; Conclusions.

The fine structure of bivalents in metaphase I spermatocytes of two Lepidoptera species, Orgyia thyellina Butler (n = 11) and O. antiqua (L.) (n = 14) (Lymantriidae), and a Trichoptera species, Limnephilus decipiens (Kolenatý) (n = 10) (Limnephilidae) were studied using a series of ultrathin sections and transmission electron microscopy. The bulk of species in both orders possess a haploid chromosome number of about 30. Thus, the experimental species have relatively small chromosome numbers. This study showed that metaphase I bivalents in both Lepidoptera species are polykinetic; attachment of kinetochore microtubules is found scattered throughout the entire poleward chromosomal surface. The microtubules were inserted in material of medium electron density. A pair of distinct kinetochore plates, consisting of material of about the same electron density as the chromatin, was detected at each poleward chromosomal surface in metaphase I bivalents of the caddis-fly, L. decipiens. The observations suggest that DNA elements responsible for the organization of the kinetochores are dispersed throughout the chromosomes in the two Lepidoptera species, whereas they are narrowly clustered in the Trichoptera. Thus, karyotype evolution in the closely related Lepidoptera and the Trichoptera involved widely differing mechanisms. [ABSTRACT FROM AUTHOR]

Natural rubber with 50 mol % epoxidation (ENR-50) was filled with carbon nanotubes (CNTs) and conductive carbon black (CCB) hybrid fillers with various CCB loadings of 2.5, 5.0, 7.0, 10.0 and 15.0 phr, and the compounds were mixed with ferric ion (Fe3+) as a crosslinking agent. The ENRs filled exclusively with CNTs, and CNT–CCB hybrid fillers exhibited typical curing curves at different CCB loadings, i.e., increasing torque with time and thus crosslinked networks. Furthermore, the incorporation of CNT–CCB hybrid fillers and increasing CCB loadings caused an enhancement of tensile properties (modulus and tensile strength) and crosslink densities, which are indicated by the increasing torque difference and the crosslink densities. The crosslink densities are determined by swelling and temperature scanning stress relaxation (TSSR). Increasing CCB loadings also caused a significant improvement in bound rubber content, filler–rubber interactions, thermal resistance, glass transition temperature (Tg) and electrical conductivity. A combination of 7 phr CNT and CCB with loading higher than 2.5 phr gave superior properties to ENR vulcanizates. Furthermore, the secondary CCB filler contributes to the improvement of CNT dispersion in the ENR matrix by networking the CNT capsules and forming CNT–CCB–CNT pathways and thus strong CNT–CCB networks, indicating the improvement in the tensile properties, bound rubber content and dynamic properties of the ENR composites. Moreover, higher electrical conductivity with a comparatively low percolation threshold of the hybrid composites was found as compared to the ENR filled with CNTs without CCB composite. The superior mechanical and other properties are due to the finer dispersion and even distribution of CNT–CCB hybrid fillers in the ENR matrix. [ABSTRACT FROM AUTHOR]

A timeline is presented of 50 years of the periodical "Crystal Research and Technology" between 1966 and 2016.

Land-based, high-frequency (HF) surface wave radar has the unique capability of monitoring coastal surface parameters, such as current, waves, and wind, up to 200 km off the coast. The Doppler spectrum of the backscattered radar signal is characterized by two strong peaks that are caused by the Bragg-resonant scattering from the ocean surface. The wavelength of Bragg resonant waves is exactly half the radio wavelength (grazing incidence), and these waves are located at the higher frequency part of the wave spectral distribution. When HF radar operates at higher frequencies, the resonant waves are relatively shorter waves, which are more sensitive to a change in wind direction, and they rapidly respond to local wind excitation and a change in wind direction. When the radar operates at lower frequencies, the corresponding resonant waves are relatively longer and take longer time to respond to a change in wind direction due to the progress of wave growth from short waves to long waves. For the wind inversion from HF radar backscatter signals, the accuracy of wind measurement is also relevant to radar frequency. In this paper, a pattern-fitting method for extracting wind direction by estimating the wave spreading parameter is presented, and a comparison of the pattern-fitting method and a conventional method is given as well, which concludes that the pattern-fitting method presents better results than the conventional method. In order to analyze the wind direction inversion from radar backscatter signals under different wind conditions and at different radar frequencies, two radar experiments accomplished in Norway and Italy are introduced, and the results of wind direction inversion are presented. In the two experiments, the radar worked at 27.68 MHz and 12 MHz, respectively, and the wind conditions at the sea surface were quite different. In the experiment in Norway, 67.4% of the wind records were higher than 5 m/s, while, in the experiment in Italy, only 18.9% of the wind records were higher than 5 m/s. All these factors affect the accuracy of wind direction inversion. The paper analyzes the radar data and draws a conclusion on the influencing factor of wind direction inversion. [ABSTRACT FROM AUTHOR]

Introduces a series of articles about robotics and autonomous systems.

The author reflects on celebrating 2014 as the International Year of Crystallography (IYCr2014). The author states that the celebration will be jointly organized by the United Nations, Educational, Scientific and Cultural Organizations (UNESC)) and International Union of Crystallography (IUCr). The author notes that its opening ceremony will be in Paris, France on January 20-21, 2014. The author mentions that it will celebrate the 100th anniversary of the award of Nobel Prize to Max von Laue.

An introduction is presented in which the author discusses various topics within the issue including industrial crystallography, crystal growth, and material science.