Distinct Planes Research Articles

Silver-Assisted Synthesis of Gold Nanorods: the Relation between Silver Additive and Iodide Impurities.

Seed-mediated methods employing cetyltrimethylammonium bromide (CTAB) as a surfactant, and silver salts as additives, are the most common synthetic strategies for high-yield productions of quality Au nanorods. However, the mechanism of these reactions is not yet fully understood and, importantly, significant lab-to-lab reproducibility issues still affect these protocols. In this study, the direct correlation between the hidden content of iodide impurities in CTAB reagents, which can drastically differ from different suppliers or batches, and the optimal concentration of silver required to maximize the nanorods yield is demonstrated. As a result, high-quality nanorods are obtained at different iodide contents. These results are interpreted based on the different concentrations of CTAB and cetyltrimethylammonium iodide (CTAI) complexes with Ag+ and Au+ metal ions in the growth solution, and their different binding affinity and reduction potential on distinct crystallographic planes. Notably, the exhaustive conversion of CTAI-Au+ to CTAI-Ag+ appears to be the key condition for maximizing the nanorod yield.

Exhumed subglacial landscape in Uruguay: Erosional landforms, depositional environments, and paleo-ice flow in the context of the late Paleozoic Gondwanan glaciation

A well-exposed glacial surface sculpted on Precambrian crystalline basement rocks occurs below the glacial succession of the San Gregorio Formation on the eastern border of the Chaco-Parana Basin in Uruguay and was formed in the context of the late Paleozoic Gondwana Ice Age. On the glacial surface are asymmetric parallel streamlined bedrock landforms interpreted as whalebacks. The downglacier (lee-side) faces of the whalebacks have gentle slopes dipping NNW with striated and sometimes polished surfaces on crystalline rocks. These landforms are covered by 10–100-cm-thick layers of tillites and shear-laminated siltstones, suggesting glacial abrasion produced mainly by subglacial till sliding. The subglacial facies are ice-molded, and exhibit meso-scale glacial lineations such as ridges and grooves up to 30 m long and 30 cm deep. The subglacial association is directly overlain by proglacial fine-grained facies (rhythmites) with dropstones indicating a subaqueous depositional environment following ice-margin retreat. The fine-grained facies are erosively cut by a succession of sandstones with wave-generated stratification resting on a basal conglomerate. Intraformational striated surfaces, NNE-oriented, were found on four distinct bedding planes within the sandstone package and interpreted as ice keel scour marks produced by floating ice. The San Gregorio deposits are partially confined in a wide and shallow subglacial trough and the stratigraphic succession is interpreted as the record of a glacial advance-retreat cycle comparable to deglacial sequences from other late Paleozoic localities. The paleo-ice flow to the NNW indicated by subglacial lineations is parallel to that verified in the southernmost Paraná Basin located north of the study area, suggesting a paleogeographic scenario in which glaciers advanced northward into a glaciomarine environment. The proposed palaeogeography does not confirm the previous hypothesis of an ice center on the Sul-Riograndense Shield but, instead, it corroborates a south-derived Uruguayan Ice Lobe advancing to the north, probably with provenance far afield in terranes of the present-day southern African.

Integration of root systems into a GIS-based slip surface model: computational experiments in a generic hillslope environment

Root systems of trees reinforce the underlying soil in hillslope environments and therefore potentially increase slope stability. So far, the influence of root systems is disregarded in Geographic Information System (GIS) models that calculate slope stability along distinct failure plane. In this study, we analyse the impact of different root system compositions and densities on slope stability conditions computed by a GIS-based slip surface model. We apply the 2.5D slip surface model r.slope.stability to 23 root system scenarios imposed on pyramidoid-shaped elements of a generic landscape. Shallow, taproot and mixed root systems are approximated by paraboloids and different stand and patch densities are considered. The slope failure probability (Pf) is derived for each raster cell of the generic landscape, considering the reinforcement through root cohesion. Average and standard deviation of Pf are analysed for each scenario. As expected, the r.slope.stability yields the highest values of Pf for the scenario without roots. In contrast, homogeneous stands with taproot or mixed root systems yield the lowest values of Pf. Pf generally decreases with increasing stand density, whereby stand density appears to exert a more pronounced influence on Pf than patch density. For patchy stands, Pf increases with a decreasing size of the tested slip surfaces. The patterns yielded by the computational experiments are largely in line with the results of previous studies. This approach provides an innovative and simple strategy to approximate the additional cohesion supplied by root systems and thereby considers various compositions of forest stands in 2.5D slip surface models. Our findings will be useful for developing strategies towards appropriately parameterising root reinforcement in real-world slope stability modelling campaigns.

Instability of warped discs

Accretion discs are generally warped. If a warp in a disc is too large, the disc can `break' apart into two or more distinct planes, with only tenuous connections between them. Further if an initially planar disc is subject to a strong differential precession, then it can be torn apart into discrete annuli that precess effectively independently. In previous investigations, torque-balance formulae have been used to predict where and when the disc breaks into distinct parts. In this work, focusing on discs with Keplerian rotation and where the shearing motions driving the radial communication of the warp are damped locally by turbulence (the `diffusive' regime), we investigate the stability of warped discs to determine the precise criterion for an isolated warped disc to break. We find and solve the dispersion relation, which in general yields three roots. We provide a comprehensive analysis of this viscous-warp instability and the emergent growth rates and their dependence on disc parameters. The physics of the instability can be understood as a combination of (1) a term which would generally encapsulate the classical Lightman-Eardley instability in planar discs (given by $\partial(\nu\Sigma)/\partial\Sigma < 0$) but is here modified by the warp to include $\partial(\nu_1|\psi|)/\partial|\psi| < 0$ and (2) a similar condition acting on the diffusion of the warp amplitude given in simplified form by $\partial(\nu_2|\psi|)/\partial|\psi| < 0$. We discuss our findings in the context of discs with an imposed precession, and comment on the implications for different astrophysical systems.

The accuracy of distance perception in the frontal plane of projection‐based stereoscopic environments

AbstractAn experiment was conducted to investigate the accuracy of distance judgment in a frontal plane of projection‐based stereoscopic environments. The targets were presented at nine distinct frontal plane positions and at three depth levels. Eighteen right‐handed participants with self‐declared normal visual acuity reached the target, either continuously visible or presented briefly, by holding pointing sticks. All combinations of the experimental conditions were repeated for an equivalent real‐world environment. Accuracies of judgments were then computed from three‐dimensional data collected by a motion system composed of six infrared cameras. As compared with about 94% accuracy in the physical world, the space in the frontal plane was only about 85% on the stereoscopic environment. The result also revealed more accurate judgment in the continuous presence of the target. Furthermore, the accuracy was affected by the egocentric distance of the frontal plane from the position of the participant. The study concluded that the compression in the frontal plane and underestimation of depth, which has been reported by the majority of previous studies could be an indication that the space compression in virtual environments might be in all the three‐dimensions. These findings can be used as guidelines for developers and content designers to properly locate virtual targets and selection of efficient interaction modes.

Outcomes of Subfascial, Suprafascial, and Super-Thin Anterolateral Thigh Flaps: Tailoring Thickness without Added Morbidity

Subfascial anterolateral thigh (ALT) flap thickness can be problematic with regards to bulk, oral competence, shoe-fit, or as a potential source of recurrent wound breakdown. We have utilized distinct upper thigh fascial planes to fashion thin (suprafascial) or super-thin (periscarpal) ALT flaps to improve surface topography. We compared outcomes based on ALT flap thickness to determine any significant differences in extremity coverage and reconstruction. Analysis was completed on patients who consecutively underwent ALT free tissue transfer at a single institution from May 2012 to January 2017. Patient's operative, and postoperative characteristics were evaluated. Univariate analysis determined differences among matching as well as functional outcomes. A multivariable regression identified independent risk factors associated with patient, donor site, and flap complications. Fifty-one patients met inclusion criteria. Of these, 16 (31.4%) underwent traditional subfascial ALT flaps, and 35 (68.6%) underwent suprafascial (N = 23) or super-thin (N = 12) flaps. Thin flap patients were more likely to use tobacco (42.9% versus 6.3%; p < 0.01), have fewer perforators (1.20 ± 0.41 versus 1.64 ± 0.63; p < 0.009), and shorter mean operative times (425.9 ± 87.8 versus 511.9 ± 79.9; p < 0.002), but nearly identical flap sizes (163 cm2 versus 168 cm2). There were no significant differences in flap complications (18% versus 22%) or donor-site complications (6.3% versus 5.7%) between the thick and thin cohorts, respectively (p > 0.05). In subgroup analysis, diabetes mellitus was an independent risk factor for donor site morbidity (odds ratio [OR] = 1.23; p = 0.027) for all groups, whereas tobacco use and obesity (body mass index [BMI] > 30) failed to significantly alter outcomes independently. Tailoring ALT thickness can be performed safely without compromising flap outcomes or patient morbidity. Suprafascial and super-thin ALTs allowed for safe, precise solutions for tissue coverage.

Managerial Accounting and Society: Emerging Factors for ‘Decision Making’ of Accountants in the Modern Era

The managerial accounting offers a universal set of tools to manage the administration and acts as patterned entities for producing a return for the organization. In doing so, the chief problem faced by a professional and academic discipline like accounting is that it has to deal with two distinct planes: one is the theoretical stage, and the other is on the practical height. Since the influence of accounting affects areas beyond mere corporate and business entities to the day-to-day social role of accounting, the discipline must pay proper discretion in addressing both the aspects. This paper address three complicates issues that the modern day accounting is facing. First, it attempts to shed lights on the sociological concepts applicable in accounting to comprehend the implicative insinuations. Second, the civil discourse and the decision-making edifice of the management have taken under consideration. Third, it intends an approach to reconstruct the behavioral accounting.&#x0D;

Seismicity at Lusi and the adjacent volcanic complex, Java, Indonesia

We study the local seismicity in East Java around the Arjuno-Welirang volcanic complex that is connected via the Watukosek Fault System, to the spectacular Lusi eruption site. Lusi is a sediment-hosted hydrothermal system which has been erupting since 2006. It is fed by both mantellic and hydrothermal fluids, rising and mixing with the thermogenic gases and other fluids from shallower sedimentary formations. During a period of 24 months, we observe 156 micro-seismic earthquakes with local magnitudes ranging from ML0.5 to ML1.9, within our network. The events predominantly nucleate at depths of 8–13 km below the Arjuno-Welirang volcanic complex. Despite the geological evidence of active tectonic deformation and faulting observed at the surface, practically no seismicity is observed in the sedimentary basin hosting Lusi. Although we cannot entirely rule out artifacts due to an increased detection threshold in the sedimentary basin, the deficit in significant seismicity suggests aseismic deformation beneath Lusi due to the large amount of fluids that may lubricate the fault system. An analysis of focal mechanisms of nine selected events around the Arjuno-Welirang volcanic complex indicates predominantly strike-slip faulting activity in the region SW of Lusi. This type of activity is consistent with observable features such as fault escarpment, river deviation and railroad deformation; suggesting that the Watukosek fault system extends from the volcanic complex towards the NE of Java. Our results point out that the tectonic deformation of the region is characterized by a segmented fault system being part of a broader damage zone, rather than localized along a distinct fault plane.

Development of a 2-dof uterine manipulator with LED illumination system as a new transvaginal uterus amputation device for gynecological surgeries

Background: Hysterectomy, the most common major gynecological operation worldwide, consists of removal of the uterus and can be performed abdominally, vaginally, or laparoscopically. A uterine manipulator is a key device used for uterine manipulation and cannulation in hysterectomies. The challenges of conventional manipulators are to move the uterus in two distinct planes and to identify cervical landmarks during circular cut and coagulation.Material and methods: In this study, a structural synthesis of the two degrees of freedom parallel manipulator was performed considering the constraints noted by surgeons. Computer-aided design and assembly of the manipulator, the cervicovaginal cap with LEDs, and the external parts were performed before rapid prototyping. The final design of the uterine manipulator was then manufactured from stainless steel and tested on an artificial uterus model using a test chamber.Results: This article presents the design, production and testing processes of an innovative manipulator with a motion capability up to 80° workspace both in the sagittal and coronal planes and an illumination system, easily detectable by the laparoscope, was successfully implemented on the manipulator’s cervical cap in order to overcome the drawbacks of conventional uterine manipulators.Conclusions: Despite all the current studies and uterine manipulators on the market, no research has incorporated all the features mentioned above.

A novel dual-color bifocal imaging system for single-molecule studies.

In this paper, we report the design and implementation of a dual-color bifocal imaging (DBI) system that is capable of acquiring two spectrally distinct, spatially registered images of objects located in either same or two distinct focal planes. We achieve this by separating an image into two channels with distinct chromatic properties and independently focusing both images onto a single CCD camera. The two channels in our device are registered with subpixel accuracy, and long-term stability of the registered images with nanometer-precision was accomplished by reducing the drift of the images to ∼5 nm. We demonstrate the capabilities of our DBI system by imaging biomolecules labeled with spectrally distinct dyes and micro- and nano-sized spheres located in different focal planes.

Mean-Field Dynamics of Inter-Switching Memes Competing Over Multiplex Social Networks

This letter characterizes the intertwined behavior of a susceptible-infected-susceptible epidemic model involving multiple mutually exclusive memes, each competing over distinct contact planes of an undirected multi-layer social network, with the possibility of inter-switching. Based on the mean-field theory, we contrast and derive closed-form analytical expressions for the steady-state thresholds that govern the transitions between extinction, co-existence, and absolute dominance of the inter-switchable memes. Moreover, a non-linear optimization formulation is presented to determine the optimal budget allocation for controlling the switching rates to a particular co-existing meme. Validated by simulations, the impact of switching on the tipping thresholds and their implications in reality are demonstrated using data extracted from online social networks.

Strength and Deformation Behavior of Fiber-Reinforced Cohesive Soil Under Varying Moisture and Compaction States

An experimental study was carried out to investigate the effects of glass fiber reinforcement on the strength and deformation behavior of a cohesive soil under different compaction states by means of unconfined compression tests. The specimens were prepared with varying fiber contents, fiber lengths, dry unit weight and moisture content other than maximum dry unit weight and optimum moisture content of the soil. From the test results, peak strength, failure axial strain, secant modulus and energy absorption capacity of the reinforced soil specimens were calculated and compared with that of the unreinforced soil. The results showed that the relative benefits of fiber reinforcement are highly dependent on the moisture content and dry unit weight of the soil specimens. The peak strength of the reinforced soil specimen increases gradually with increase in dry unit weight, whereas the improvement of peak strength with moisture content occurs up to optimum moisture content. The brittle failure pattern with a single distinct shear plane of the unreinforced soil specimens is gradually transformed to multi-shear failure pattern along with barreling shape at low fiber content, and then to plastic bulging failure with a network of minor fissures at higher fiber content.

Tooth enamel microstructures of three Jurassic euharamiyidans and implications for tooth enamel evolution in allotherian mammals

ABSTRACT Incisor enamel microstructures of three euharamyidans, Shenshou lui, Xianshou linglong, and X. songae, from the early Late Jurassic Yanliao Biota, Liaoning Province, China, are reported. The enamel of the three species consists of columnar divergence units that are delimited by planes of crystallite convergence and have irregular shapes and sizes, but there is no distinct line or plane along the divergent axis of crystallites in the unit. Of the three species, the enamel of S. lui is most primitive in having simpler enamel units that are roughly perpendicular to the enamel dentine junction. In Xianshou, the enamel units are oblique apically, and crystallites in the inner zone of enamel show greater differentiation to form erratically spaced clusters that resemble incipient prism-like; seam-like and sheath-like structures are also present. This enamel type may represent a transitional stage between prismless and prismatic enamel. Mapping enamel types from selected taxa of basal mammaliaforms on a simplified phylogeny, the columnar enamel in Thomasia, Shenshou, and some ‘plagiaulacoid’ multituberculates is interpreted as the plesiomorphic condition for allotherians, from which evolved the transitional enamel, as represented by Xianshou and the ‘plagiaulacoid’ Paulchoffatia, and the plesiomorphic prismatic enamel as in some post-‘plagiaulacoid’ multituberculates and gondwanatherians. The prismatic enamel in advanced multituberculates and other gondwanatherians may have evolved independently. Despite the new enamel morphologies revealed in euharamiyidans, the amelogenesis mechanism of how prisms, seams, and sheaths evolved within mammals remains unclear. SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVP Citation for this article: Mao, F.-Y., Y.-Q. Wang, S.-D. Bi, J. Guan, and J. Meng. 2017. Tooth enamel microstructures of three Jurassic euharamiyidans and implications for tooth enamel evolution in allotherian mammals. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2017.1279168.

Mimicking the behaviour of rigid rod molecules. Smectic H liquid crystals from amphiphilic quaternary ammonium salts

ABSTRACTThe effect of secondary hydrogen-bonding interactions on the crystalline and liquid crystalline phases of quaternary ammonium salts functionalised with a carboxylic group attached at the polar head through a decyl spacer of a homologous series of N-alkyl-N-carboxydecyl-N,N-dimethylammonium bromides was investigated by polarising optical microscopy, differential scanning calorimetry and X-ray diffraction. The low-temperature crystal phases were found to have a lamellar structure in which the ammonium bromide groups are arranged within the layers in two distinct planes, alternately separated by single layers of alkyl chains and double layers of carboxydecyl chains coupled through the carboxyl end groups. At higher temperatures, although these molecules were made from soft flexible chains, smectic H mesophases were identified. The smectic layers were found to be formed by the same two ionic planes alternately separated by the alkyl and carboxydecyl sub-layers. The smectic structure was compared with the three-dimensional positional order observed in the smectic T phase of dihydroxyl functionalised quaternary ammonium salts already described in the literature.

Remote focusing multifocal plane microscopy for the imaging of 3D single molecule dynamics with cellular context.

Three-dimensional (3D) single molecule fluorescence microscopy affords the ability to investigate subcellular traffcking at the level of individual molecules. An imaged single molecule trajectory, however, often reveals only limited information about the underlying biological process when insuffcient information is available about the organelles and other cellular structures with which the molecule interacts. A new 3D fluorescence microscopy imaging modality is described here that enables the simultaneous imaging of the trajectories of fast-moving molecules and the associated cellular context. The new modality is called remote focusing multifocal plane microscopy (rMUM), as it extends multifocal plane microscopy (MUM) with a remote focusing module. MUM is a modality that uses multiple detectors to image distinct focal planes within the specimen at the same time, and it has been demonstrated to allow the determination of 3D single molecule trajectories with high accuracy. Remote focusing is a method that makes use of two additional objective lenses to enable the acquisition of a z-stack of the specimen without having to move the microscope's objective lens or sample stage, components which are required by MUM to be fixed in place. rMUM's remote focusing module thus allows the cellular context to be imaged in the form of z-stacks as the trajectories of molecules or other objects of interest are imaged by MUM. In addition to a description of the modality, a discussion of rMUM data analysis and an example of data acquired using an rMUM setup are provided in this paper.

Variation in Morphometry of Vastus Medialis Muscle.

The Vastus Medialis (VM) muscle divides into two parts, proximal Vastus Medialis Longus (VML) and distal Vastus Medialis Obliquus (VMO). The VMO originates from the tendon of adductor magnus and insert into the medial border of patella and these fibers are nearly horizontal. It exerts medial force vector to counter the lateral force vector of Vastus Lateralis (VL) hence the VM presents a biomechanical advantage over the VL. The functional importance of VML and VMO is well explained but the anatomical evidence of separate identity of VMO is lacking. To determine muscle fiber angles and lengths of VML and VMO, to find out the distinct nerve supply and fascial plane between VML and VMO and to evaluate VM insertion in relation to patella. Thirty intact lower limbs (right-15 and left- 15) from 15 donated cadavers with an age 60 years and above were dissected. Lengths and angles of VML, VMO superior (VMOs) and VMO inferior (VMOi) were measured. The fascial plane and the femoral nerve and its branches supplying VM were dissected and terminal branches were traced in each section with the blunt dissection. All parameters were recorded and statistical analysis was done using one-way ANOVA. The VMO took origin from the adductor magnus muscle and attached to the patella. VMOi was present in 83.33% cases (25 limbs), and inserted to the medial border of patella. The percentages of VML, VMOs and VMOi lengths compared to total VM length were 65.54±4.84, 25.23±4.20 and 9.22±2.17 respectively. The fiber angles ranged for VML, VMOs and VMOi were between 18 to 32, 30 to 46 and 46 to 56 degrees respectively. There were significant differences among all groups (p=0.001). These two parts were not separated by distinct fascial plane and no separate nerve supply was observed but the richest nerve supply to VMO was noted. The present study conclude that VMO is having obtuse angle, horizontal fibers and richest nerve supply as compared to proximal part which make it functionally as a separate entity but not anatomically.

Two-photon optical microscopy imaging of endothelial keratoplasty grafts.

To investigate the microstructure of endothelial keratoplasty grafts using two-photon optical microscopy. Six endothelial keratoplasty grafts obtained from human donor corneoscleral tissues and prepared by submerged hydrodissection technique were imaged by two-photon optical microscopy. In each graft, two liquid bubbles were created in order to investigate the presence of a conserved cleavage plane regardless of the volume of posterior stroma that remained attached to Descemet's membrane (DM); the first bubble (bubble A) was generated under DM and the second bubble (bubble B) injection was done in order to obtain a layer of deep stroma that kept the two bubbles separated. Six human donor corneoscleral tissues were used as controls. Second harmonic generation and two-photon emitted fluorescence signals were collected from each specimen. Dissection of stroma occurred along the posterior collagen lamellae at variable distance from DM, which ranged between 3 and 16 μm in bubble A and between 23 and 41 μm in bubble B. The residual stroma included, anteriorly, bands of collagen lamellae, and thin bundles of stromal collagen fibrils, posteriorly, which were tightly intertwining with the underlying DM. There was no anatomically distinct plane of separation between these pre-Descemetic stromal collagen bundles and the overlying collagen lamellae with this hydrodissection technique. Two-photon optical microscopy provided label-free high-resolution imaging of endothelial keratoplasty grafts, showing that the most posterior stroma changes organization at approximately 10 μm above the DM. The pre-Descemetic stromal collagen fibrils form an intertwined complex with DM, which cannot be separated using hydrodissection.

Characterizing the mechanical behaviour of the Tournemire argillite

Abstract A laboratory programme of uniaxial, triaxial, cyclic and Brazilian tests was conducted to investigate the anisotropic mechanical behaviour of the Tournemire argillite, with different axial loading orientations with respect to the bedding planes (i.e. loading orientation angle, θ=0°, 30°, 45°, 60° and 90°). The experimental results show that both strength and deformation of the argillite are direction-dependent. Failure occurs in a brittle manner with a sudden collapse of the material strength. The failure mode exhibits localization along distinct failure planes and also depends on the loading orientation. This paper summarizes the experimental results and describes constitutive relationships that were developed in order to simulate the stress–strain behaviour of the Tournemire argillite. A microstructure tensor approach is adopted in order to take into account the anisotropic behaviour of the argillite. The identification procedure for material function and parameters is outlined, and the model is applied to simulate the set of triaxial tests performed at different levels of confining pressure and orientation of the bedding planes. It is demonstrated that the model adequately reproduces the anisotropy, the pre-peak stress–strain response and the onset of material collapse in those tests.

Synthesis of hierarchically structured materials: microporous diatoms and nanoporous hydroxyaluminosilicate

Diatomite is well known to remove particulate matter for a broad range of applications due to diatom skeleton structures. Hydrothermally treated diatomite has been demonstrated to be a feasible pathway to produce advanced materials for the removal of aqueous heavy metal ions. However, single-synthesis routes to obtain altered diatomite for simultaneous removal of dissolved and particulate contaminants are still missing. Therefore, hydrothermal experiments at pH 12.8 ([KOH] = 0.1 M), and T = 100 °C and different added Al concentrations (0 mM ≤ [Al] ≤ 11 mM) were conducted. Results reveal that in comparison with previous experiments (Hollen et al. in J Mater Sci Eng B 2(10):523–533, 2012) using less alkaline solutions slower dissolution of diatomite is triggering the formation of nanosized spherical particles (NSP) in the presence of diatom skeleton relicts. NSP ranged between 10 and 50 nm in size and were located within the micropores of the diatoms (100–200 nm). TEM-SAED analyses of NSP indicated nanocrystalline phases with distinct lattice planes of 0.45 and 0.26 nm, which could not be attributed to common aluminosilicates. In accordance with the small crystal size, no X-ray diffraction peaks occurred in the bulk reaction product using powder XRD analyses. Metal ion removal experiments at ambient temperature indicated its high removal capacities for aqueous Cu2+, Pb2+ and Zn2+ ranging from 10 to 99 % (e.g., ion sorption capacities of about 0.02–0.2 mval/g). The synthesized product was also successfully tested for its metal ion removal behaviour using a mine drainage solution containing Cd2+, Pb2+, Zn2+ and Sr2+. The developed synthesis path yields a hierarchically structured material based on combined micropores (about 100 nm) from the diatoms and NSP with nanopores (1–5 nm) which is promising for large-scale production to simultaneously remove dissolved and particulate contaminants from aqueous solutions.

Galvanic Vestibular Stimulation: Cellular Substrates and Response Patterns of Neurons in the Vestibulo-Ocular Network.

Galvanic vestibular stimulation (GVS) uses modulated currents to evoke neuronal activity in vestibular endorgans in the absence of head motion. GVS is typically used for a characterization of vestibular pathologies; for studies on the vestibular influence of gaze, posture, and locomotion; and for deciphering the sensory-motor transformation underlying these behaviors. At variance with the widespread use of this method, basic aspects such as the activated cellular substrate at the sensory periphery or the comparability to motion-induced neuronal activity patterns are still disputed. Using semi-intact preparations of Xenopus laevis tadpoles, we determined the cellular substrate and the spatiotemporal specificity of GVS-evoked responses and compared sinusoidal GVS-induced activity patterns with motion-induced responses in all neuronal elements along the vestibulo-ocular pathway. As main result, we found that, despite the pharmacological block of glutamatergic hair cell transmission by combined bath-application of NMDA (7-chloro-kynurenic acid) and AMPA (CNQX) receptor blockers, GVS-induced afferent spike activity persisted. However, the amplitude modulation was reduced by ∼30%, suggesting that both hair cells and vestibular afferent fibers are normally recruited by GVS. Systematic alterations of electrode placement with respect to bilateral semicircular canal pairs or alterations of the bipolar stimulus phase timing yielded unique activity patterns in extraocular motor nerves, compatible with a spatially and temporally specific activation of vestibulo-ocular reflexes in distinct planes. Despite the different GVS electrode placement in semi-intact X. laevis preparations and humans and the more global activation of vestibular endorgans by the latter approach, this method is suitable to imitate head/body motion in both circumstances. Galvanic vestibular stimulation is used frequently in clinical practice to test the functionality of the sense of balance. The outcome of the test that relies on the activation of eye movements by electrical stimulation of vestibular organs in the inner ear helps to dissociate vestibular impairments that cause vertigo and imbalance in patients. This study uses an amphibian model to investigate at the cellular level the underlying mechanism on which this method depends. The outcome of this translational research unequivocally revealed the cellular substrate at the vestibular sensory periphery that is activated by electrical currents, as well as the spatiotemporal specificity of the evoked eye movements, thus facilitating the interpretation of clinical test results.