Horizontal Slices Research Articles

Slopes stability analysis from Rosia Poieni open pit mine, Romania

In the case of Roşia Poieni open pit mine the level of +805 m was established as a daily operating limit; the division into benches was based on this level by dividing into horizontal slices with a thickness of 15 m, equal to the height of the bench. Thus, there were 27 benches in the Curmătura area and 23 benches in the Ruginiş area. The general slope angle was set at 35°, the angle for which the tailings volumes and implicitly the opening-up coefficient were calculated. The stability analysis was performed for individual bench, 2 benches system and the general slope of the quarry (consisting of 24 benches), using two methods (Fellenius and Janbu). A polygonal slip surface was also modelled; such potential landslide surfaces can appear in the slopes of the Roşia Poieni quarry due to the natural cracking systems of the massif but also due to the secondary cracking generated by the used drilling-blasting works (exploitation technology). The stability check was done by applying Hoek’s graphical-analytical method; the determined values for the safety factor satisfy the condition of being greater than 1.3. In these circumstances, no further measures are required to increase the stability reserve.

VCfMRI: A Matlab Toolbox for Visualization and Conversion of fMRI Data Modalities

In this work, a novel conversion and visualization fMRI (VCfMRI) toolbox is proposed. The VCfMRI tool is enabled to read, write 3-D volume data (.dcm, .nii, .img, hdr and .mat format) as well as multi conversion operations between them are performed in the same package. In the current work, real fMRI data are used and all data are acquired by MRI scanner type Siemens/3T in National Magnetic Resonance Research Center (UMRAM)-Bilkent University. About 62 analyses functions have been implemented and incorporated in analysis about 7 GUI tools for multiple conversions of fMRI modalities, reading/writing and viewing in all fMRI data formats, visualizing 3-dimensional (sagittal, coronal and horizontal slices) statistical and non-statistical neuroimaging, thresholding and overlaying viewing. The presented package is a simple tool to address several issues that related to complexity in visualizing and conversion between multi-formats of fMRI data. This work enables the user to visualize and deals with fMRI data in an easy way especially for physicians, healthcare specialists and researchers whose faced challenges about how handling with these type of data.

Searching for Critical Slip Surface of Slope Based on Flower Pollination Algorithm

In order to determine the critical sliding surface of the slope, the most dangerous sliding surface was searched by flower pollination algorithm. First, the method is applied to the traditional vertical slice method for slope stability analysis. The results are very close to those of the Autobank program, indicating that the method can search the critical sliding surface and find the optimal solution. Then, the method is applied to the new horizontal slice method, and the results of the calculation examples are better than those given in the references, indicating that the application of the flower pollination algorithm to the horizontal slice method is reasonable, reliable and superior. The successful application of this method provides a new method for determining the most dangerous sliding surface of slope.

Non-Neutralized Electric Current of Active Regions Explained as a Projection Effect

Active regions (ARs) often possess an observed net electric current in a single magnetic polarity. We show that such "non-neutralized" currents can arise from a geometric projection effect when a twisted flux tube obliquely intersects the photosphere. To this end, we emulate surface maps of an emerging AR by sampling horizontal slices of a semi-torus flux tube at various heights. Although the tube has no net toroidal current, its poloidal current, when projected along the vertical direction, amounts to a significant non-neutralized component on the surface. If the tube emerges only partially as in realistic settings, the non-neutralized current will 1) develop as double ribbons near the sheared polarity inversion line, (2) positively correlate with the twist, and 3) reach its maximum before the magnetic flux. The projection effect may be important to the photospheric current distribution, in particular during the early stages of flux emergence.

TCAD simulation of small-pitch 3D sensors for pixel detector upgrades at High Luminosity LHC

Applications at the High Luminosity LHC (HL-LHC) have required the development of a new generation of 3D pixel sensors with increased pixel granularity, extreme radiation hardness and low material budget. To this purpose, new 3D pixels have small pitch (e.g., 50×50 or 25×100 μm2) and reduced active thickness (∼100 μm). Owing to the small inter-electrode spacing (∼28 μm in the most aggressive designs). These 3D pixels are expected to be radiation hard even after irradiation at the hadron fluences. Indeed, they are of interest for the innermost tracking layers of ATLAS and CMS (∼2×1016 neq cm−2), and beyond. In order to estimate the charge collection efficiency (CCE) after irradiation, TCAD simulations can be conveniently used, providing useful information for the optimization of sensor design and fabrication technology. Within the AIDA-2020 project, with reference to the new single-sided 3D technology from FBK (Trento, Italy), we have simulated the CCE of pixel sensors with different inter-electrode spacing irradiated at different fluences. For these simulations, a 2D domain was used, consisting of a horizontal slice taken at half the depth of a 3D sensor. Simulations consider the hit of a minimum ionizing particle, described by the Heavy Ion model at different points within the active area. In addition, bulk radiation damage is accounted by using advanced deep-level trap models. This paper reports a comprehensive description of the simulation results based on a radiation model validated by comparison to experimental results from n-in-p strip detectors at 248 K and 900 V bias.

ВОЗРАСТНЫЕ ОСОБЕННОСТИ ГЕНЕРАЦИИ ЭПИЛЕПТИФОРМНОЙ АКТИВНОСТИ В 4-АМИНОПИРИДИНОВОЙ МОДЕЛИ В СРЕЗАХ МОЗГА КРЫСЫ

Children are more likely to develop epileptic seizures (ictal discharges lasting tens of seconds) than adults. A higher predisposition of the juvenile brain to the generation of epileptiform activity is thought to be due to a preeminence of inhibition over excitation at the early stage of brain development. However, the molecular and physiological mechanisms underlying these age-related differences are yet to be clarified. We compared the ictal activity induced by a chemoconvulsant 4-aminopyridine (4-AP) in the horizontal slices of the entorhinal cortex and hippocampus of 3- and 8-week-old Wistar rats. In 3-week-old rats, the ictal discharge was always preceded by a clearly detectable preictal activity as manifested in one or several 3−4-s GABA-glutamate events, whereas in 8-week-old rats such events were typically absent or very rare (no more than one occasional short event). The ictal activity resistance to external exposures was also age-dependent. In 8-week-old rats, by contrast to 3-week-old animals, ictal discharge generation in the entorhinal cortex was blocked completely and replaced by the 0.2−0.3 Hz interictal activity (simultaneous 1−3-s burst discharges) by a partial blockade of the KCC2-cotransporter or Na+/K+-pump, as well as by low-frequency electric stimulation. Thus, our data indicate that ictal discharges in the immature (3-week-old) brain are more resistant to external exposures than in the brain of adult rats. Interictal and ictal epileptiform activities are antagonistic in 8-week-old animals, while the appearance of interictal activity interrupts completely the generation of ictal discharges and can therefore be considered as one of the putative antiepileptic mechanisms in the mature rat brain.

Stable and isoperimetric regions in some weighted manifolds with boundary

In a Riemannian manifold with a smooth positive function that weights the associated Hausdorff measures we study stable sets, i.e., second order minima of the weighted perimeter under variations preserving the weighted volume. By assuming local convexity of the boundary and certain behavior of the Bakry–Émery–Ricci tensor we deduce rigidity properties for stable sets by using deformations constructed from parallel vector fields tangent to the boundary. As a consequence, we completely classify the stable sets in some Riemannian cylinders Ω×R with product weights. Finally, we also establish uniqueness results showing that any minimizer of the weighted perimeter for fixed weighted volume is bounded by a horizontal slice Ω×{t}.

Dynamics of curved travelling fronts for the discrete Allen-Cahn equation on a two-dimensional lattice

<p style='text-indent:20px;'>In this paper we consider the discrete Allen-Cahn equation posed on a two-dimensional rectangular lattice. We analyze the large-time behaviour of solutions that start as bounded perturbations to the well-known planar front solution that travels in the horizontal direction. In particular, we construct an asymptotic phase function <inline-formula><tex-math id="M1">\begin{document}$ \gamma_j(t) $\end{document}</tex-math></inline-formula> and show that for each vertical coordinate <inline-formula><tex-math id="M2">\begin{document}$ j $\end{document}</tex-math></inline-formula> the corresponding horizontal slice of the solution converges to the planar front shifted by <inline-formula><tex-math id="M3">\begin{document}$ \gamma_j(t) $\end{document}</tex-math></inline-formula>. We exploit the comparison principle to show that the evolution of these phase variables can be approximated by an appropriate discretization of the mean curvature flow with a direction-dependent drift term. This generalizes the results obtained in [<xref ref-type="bibr" rid="b47">47</xref>] for the spatially continuous setting. Finally, we prove that the horizontal planar wave is nonlinearly stable with respect to perturbations that are asymptotically periodic in the vertical direction.

Single breath-hold compressed sensing real-time cine imaging to assess left ventricular motion in myocardial infarction

PurposeTo evaluate the reliability of a real-time compressed sensing (CS) cine sequence for the detection of left ventricular wall motion disorders after myocardial infarction in comparison with the reference steady-state free precession cine sequence. Materials and MethodsOne hundred consecutive adult patients referred for either initial work-up or follow-up by cardiac magnetic resonance (CMR) in the context of myocardial infarction were prospectively included. There were 77 men and 23 women with a mean age of 63.12±11.3 (SD) years (range: 29–89 years). Each patient underwent the reference segmented multi-breath-hold steady-state free precession cine sequence including one short-axis stack and both vertical and horizontal long-axis slices (SSFPref) and the CS real-time single-breath-hold evaluated sequence (CSrt) providing the same slices. Wall motion disorders were independently and blindly assessed with both sequences by two radiologists, using the American Heart Association left ventricle segmentation. Paired Wilcoxon signed-rank test was used to search for differences in wall motion disorders conspicuity between both sequences and receiver operating characteristic curve (ROC) analysis was performed to assess the diagnosis performance of CSrt sequence using SSFPref as the reference method. ResultsEach patient had at least one cardiac segment with wall motion abnormality on SSFPref and CSrt images. The 1700 segments analyzed with SSFPref were classified as normokinetic (360/1700; 21.2%), hypokinetic (783/1700; 46.1%), akinetic (526/1700; 30.9%) or dyskinetic (31/1700; 1.8%). Sensitivity and specificity of the CS sequence were 99.6% (95% CI: 99.1–99.9%) and 99.7% (95% CI: 98.5–100%), respectively. Area under ROC of CSrt diagnosis performance was 0.997 (95% CI: 0.993–0.999). ConclusionCS real-time cine imaging significantly reduces acquisition time without compromising the conspicuity of left ventricular -wall motion disorders in the context of myocardial infarction.

The absence of functional bassoon at cone photoreceptor ribbon synapses affects signal transmission at Off cone bipolar cell contacts in mouse retina.

Off cone bipolar cells of the mammalian retina connect to cone photoreceptor synaptic terminals via non-invaginating flat contacts at a considerable distance from the only established neurotransmitter release site so far, the synaptic ribbon. Diffusion from the ribbon synaptic active zone is considered the most likely mechanism for the neurotransmitter glutamate to reach postsynaptic receptors on the dendritic tips of Off cone bipolar cells. We used a mutant mouse with functionally impaired photoreceptor ribbon synapses to investigate the importance of intact ribbon synaptic active zones for signal transmission at Off cone bipolar cell contacts. Whole-cell patch-clamp recordings from Off cone bipolar cells in a horizontal slice preparation of wildtype (Bsnwt ) and mutant (BsnΔEx4/5 ) mouse retina were applied to investigate signal transmission between cone photoreceptors and Off cone bipolar cells. The distribution of postsynaptic glutamate receptors in Off cone bipolar cell dendrites was studied using multiplex immunocytochemistry. Tonic synaptic activity and evoked release were significantly reduced in mutant animals. Vesicle replenishment rates and the size of the readily releasable pool were likewise decreased. The precisely timed transient current response to light offset changed to a sustained response in the mutant, exemplified by random release events only loosely time-locked to the stimulus. The kainate receptor distribution in postsynaptic Off cone bipolar cell dendritic contacts in BsnΔEx4/5 mice was largely disturbed. Our results suggest a major role of functional ribbon synaptic active zones for signal transmission and postsynaptic glutamate receptor organization at flat Off cone bipolar cell contacts.

Individual tree detection and crown delineation from Unmanned Aircraft System (UAS) LiDAR in structurally complex mixed species eucalypt forests

Estimates of forest stocking density per hectare (NHa) are important in characterising ecological conditions and assessing changes in forest dynamics after disturbances due to pyrogenic, anthropogenic and biotic factors. We use Unmanned Aircraft Systems (UAS) LiDAR with mean point density of 1485 points m−2 across 39 flight sites to develop a bottom-up approach for individual tree and crown delineation (ITCD). The ITCD algorithm was evaluated across mixed species eucalypt forests (MSEF) using 2790 field measured stem locations across a broad range of dominant eucalypt species with randomly leaning trunks and highly irregular intertwined canopy structure. Two top performing ITCD algorithms in benchmarking studies resulted in poor performance when optimised to our plot data (mean Fscore: 0.61 and 0.62), which emphasises the challenge posed for ITCD in the structurally complex conditions of MSEF. To address this, our novel bottom-up ITCD algorithm uses kernel densities to stratify the vegetation profile and differentiate understorey from the rest of the vegetation. For vegetation above understorey, the ITCD algorithm adopted a novel watershed clustering procedure on point density measures within horizontal slices. A Principal Component Analysis (PCA) procedure was then applied to merge the slice-specific clusters into trunks, branches, and canopy clumps, before a voxel connectivity procedure clustered these biomass segments into overstorey trees. The segmentation process only requires two parameters to be calibrated to site-specific conditions across 39 MSEF sites using a Shuffled Complex Evolution (SCE) optimiser. Across the 39 field sites, the ITCD algorithm had mean Fscore of 0.91, True Positive (TP) trees represented 85% of measured trees and predicted plot-level stocking (NP) averaged 94% of actual stocking (NOb). As a representation of plot-level basal area (BA), TP trees represented 87% of BA, omitted trees represented slightly smaller trees and made up 8% of BA, and a further 5% of BA had commission error. Spatial maps of NHa using 0.5 m grid-cells showed that omitted trees were more prevalent in high density forest stands, and that 63% of grid-cells had a perfect estimate of NHa, whereas a further 31% of the grid-cells overestimate or underestimate one tree within the search window. The parsimonious modelling framework allows for the two calibrated site-specific parameters to be predicted (R2: 0.87 and 0.66) using structural characteristics of vegetation clusters within sites. Using predictions of these two site-specific parameters across all sites results in mean FScore of 0.86 and mean TP of 0.77, under circumstances where no ground observations were required for calibration. This approach generalises the algorithm across new UAS LiDAR data without undertaking time-consuming ground measurements within tall eucalypt forests with complex vegetation structure.

Diabetes and stroke potentiate hippocampal inhibitory tone: A link to Alzheimer's disease/vascular dementia

AbstractBackgroundMice expressing mutated hAPP in the entorhinal cortex (EC) display, hypersynchrony of the EC‐hippocampus circuit, caused by decreased inhibitory tone (Angulo et al., NBD 2017). A similar EC inhibitory failure was also observed in mice expressing hAPOE4, (Nuriel et al., Nat Neursc 2017). Here we evaluated changes in EC‐hippocampus synaptic plasticity and neuronal properties produced by two additional AD risk factors, diabetes and ischemic strokeMethodHippocampal synaptic plasticity and single cell recordings were made from leptin mutant (db/db, diabetes) and normoglicemic (db/+) heterozygous mice 4‐6 m.o. one month following stroke (transient middle cerebral artery occlusion (tMCAo) or sham surgery. tMCAo was produced by a monofilament occluding the origin of MCA for 30 minutes. Recordings were made from horizontal hippocampal slices in aCSF. Schaffer collaterals to CA1 evoked field excitatory postsynaptic potential (fEPSPs) were measured before and after induction of long term potentiation (LTP). Finally, miniature inhibitory post‐synaptic currents (mIPSCs) in CA1 pyramidal neurons were recorded, using the whole cell configuration of patch‐clamp technique.ResultBoth control and diabetic mice developed a paradoxical larger LTP at the CA3‐CA1 synapse after stroke (i.e. db/db‐sham vs. db/db‐stroke,% of slope EPSP change = 180+/−21% vs. 250+/−16% respectively, p &lt; 0.05. Modeling with the program NEURON simulator suggested that this was due to loss of synaptic inhibition. We found that the peak amplitude of mIPSCs was smaller in CA1 neurons in the stroked hemisphere compared to the sham CA1 hemisphere in db/+ mice (db/+ sham vs. db/+ tMCAo = ANOVA; F = 14,99, p = 0.01). By contrast, CA1 mIPSCs frequency, but not amplitude, decreased in db/db tMCAo compared with db/db sham (F = 6.4, p = 0.022). The mean peak amplitude in db/db sham mice were significantly smaller than in db/+ sham mice (F = 6,2, p = 0.021)ConclusionThe data suggest that the observed difference in sham vs. tMCAo mIPSCs amplitude observed in db/+ mice is due to a post‐synaptic change in either GABA‐A receptor number or function. While, in db/db sham mice we observed a post‐synaptic inhibitory alteration, as seen in db/+ mice with stroke. After acute ischemia, an additional presynaptic inhibitory dysfunction in db/db occurs. Modeling suggests that the mechanism occurs via inhibitory synaptic pruning.

Simulation of Dewatering System in A Mine Shaft Using A Prototype Model Driving by Arduino Microprocessor

Dewatering is a process which is related to water removing from the excavation worksite during mining. In this research, a prototype model of shaft mine has been fabricated and the system is simulated using ultra sonic sensors and ARDUINOUNO microprocessor and a control monitor has been built by LABVIEW software to drive the system. Horizontal slice Method has been applied in calculations of water level. An extensive tests are carried out by measuring the water level inside the mine shaft and is compared to predicted data from the system. The recorded error is 0.22 % of the whole tank capacity at full load condition. A desired water level is calculated based on the desired time and this one is compared to the speed of sound with an interesting result of average error 0.00036s in time. This mechanism is absolutely passed with no modification and it has a flexibility to apply in various industrial aspects efficiently with low cost.

Single or Double Patch-Clamp Recordings In Ex Vivo Slice Preparation: Functional Connectivity, Synapse Dynamics, and Optogenetics.

Patch-clamp recordings are the method of choice to define cell-type specific electrophysiological properties of single neurons and the synaptic connectivity between pairs of connected neurons in brain slices. In combination with optogenetic tools, patch-clamp recordings allow for the investigation of long-range afferent connectivity from identified distant brain areas. Here we describe the necessary equipment to carry out patch clamp recordings, surgical methods for dissection and preparation of horizontal brain slices containing the hippocampus, and a step-by-step guide for establishing patch clamp recordings in the whole-cell configuration. We provide protocols for single neuron stimulation via the patch pipette and for photostimulation experiments that activate axon terminals expressing light sensitive ion channels.

Innervation of GnRH Neuron Distal Projections and Activation by Kisspeptin in a New GnRH-Cre Rat Model.

The neural mechanisms generating pulsatile GnRH release from the median eminence (ME) remain unclear. Studies undertaken in the mouse demonstrate that GnRH neurons extend projections to the ME that have properties of both dendrites and axons, termed "dendrons," and that the kisspeptin neuron pulse generator targets these distal dendrons to drive pulsatile GnRH secretion. It presently remains unknown whether the GnRH neuron dendron exists in other species. We report here the generation of a knock-in Gnrh1-Ires-Cre rat line with near-perfect targeting of Cre recombinase to the GnRH neuronal phenotype. More than 90% of adult male and female GnRH neurons express Cre with no ectopic expression. Adeno-associated viruses were used in adult female Gnrh1-Ires-Cre rats to target mCherry or GCAMP6 to rostral preoptic area GnRH neurons. The mCherry tracer revealed the known unipolar and bipolar morphology of GnRH neurons and their principal projection pathways to the external zone of the ME. Synaptophysin-labeling of presynaptic nerve terminals revealed that GnRH neuron distal projections received numerous close appositions as they passed through the arcuate nucleus and into the median eminence. Confocal GCaMP6 imaging in acute horizontal brain slices demonstrated that GnRH neuron distal projections lateral to the median eminence were activated by kisspeptin. These studies indicate the presence of a dendron-like arrangement in the rat with GnRH neuron distal projections receiving synaptic input and responding to kisspeptin.

Mapping Small-Scale Horizontal Velocity Field in Panzhinan Waterway by Coastal Acoustic Tomography.

Mapping small-scale high-precision velocity fields is of great significance to oceanic environment research. Coastal acoustic tomography (CAT) is a frontier technology used to observe large-scale velocity field in the horizontal slice. Nonetheless, it is difficult to observe the velocity field using the CAT in small-scale areas, specifically where the flow field is complex such as ocean ranch and artificial upwelling areas. This paper conducted a sound transmission experiment using four 50 kHz CAT systems in the Panzhinan waterway. Notably, sound transmission based on the round-robin method was recommended for small-scale CAT observation. The travel time between stations, obtained by correlation of raw data, was applied to reconstruct the horizontal velocity fields using Tapered Least Square inversion. The minimum net volume transport was 8.7 m3/s at 12:32, 1.63% of the total inflow volume transport indicating that the observational errors were acceptable. The relative errors of the range-average velocity calculated by differential travel time were 1.54% (path 2) and 0.92% (path 6), respectively. Moreover, the inversion velocity root-mean-square errors (RMSEs) were 0.5163, 0.1494, 0.2103, 0.2804 and 0.2817 m/s for paths 1, 2, 3, 4 and 6, respectively. The feasibility and acceptable accuracy of the CAT method in the small-scale velocity profiling measurement were validated. Furthermore, a three-dimensional (3-D) velocity field mapping should be performed with combined analysis in horizontal and vertical slices.

Anterior supra-acetabular external fixation for tile C1 pelvic fractures: a digital anatomical study and a finite element analysis.

Investigating the anatomical characteristics of supra-acetabular screw corridor as well as comparing the biomechanical stability between semi- and full-length screw external fixations for Tile C1 pelvic fractures. 50 male and 50 female uninjured pelvic CT data were converted into three-dimensional models and the supra-acetabular corridors were reconstructed by the Mimics software. The horizontal slice was redefined passing through the bilateral anterior inferior iliac spine and bilateral posterior superior iliac spine at the same time. On every horizontal slices, a 5mm diameter virtual screw was placed along with the unilateral anterior narrowing to posterior narrowing of the supra-acetabular corridor, and the relevant parameters of the semi- and full-length screw fixations were measured from inferior to superior at an interval height of 2.5mm until the width of the corridor was less than 5mm. Thus, the insertion position was located, as well as the inclination angle ranges were measured. The same procedure was done on a bilateral supra-acetabular corridor for each patient. Last, a Tile C1 pelvic finite element model was simulated and fixed with either semi- or a full-length anterior supra-acetabular external fixator. A 500N loading was tested on the model with three directions (cranial-caudal, anterior-posterior and lateral-medial) and the stiffness was determined by the max displacements. The insertion points of supra-acetabular screw for 66% (66/100) of men and 78% (78/100) of women were located at the outer lower part of the anterior inferior iliac spine (AIIS) (p < 0.001). The medial inclination angles of the screw were 29.50 ± 4.05° for men and 28.00 ± 3.78° for women (p = 0.007). The cranial inclination angles of the screw were 29.40 ± 5.38° for men and 28.57 ± 6.01° for women (p = 0.306). The safe inclination angle ranges of the semi-length screw were 3°-6° bigger than the full-length screw. For semi-length corridor, the widths were 14.07 ± 2.39mm for men and 11.29 ± 1.81mm for women (p < 0.001) and the depths were 71.77 ± 5.96mm for men and 69.26 ± 5.21mm for women (p < 0.001). For full-length corridor, the widths were 10.61 ± 2.10mm for men and 8.44 ± 2.03mm for women (p < 0.001) and the depths were 133.37 ± 7.60mm for men and 129.01 ± 8.12mm for women (p < 0.001). In the finite element analysis, the max displacements of the pelvis under three loading modes (cranial-caudal, anterior-posterior and lateral-medial) for semi-length fixation were 0.772mm, 0.409mm and 0.331mm and for full-length fixation were 0.727mm, 0.385mm and 0.262mm. The outer lower part of AIIS is recommended as an insertion point of the supra-acetabular screw with about 30° medial and cranial inclination angles, and the semi-length screw is safer for placing and has satisfactory biomechanical stability by compared with a full-length screw.

Involvement of the Retinal Pigment Epithelium in the Development of Retinal Lattice Degeneration.

Lattice degeneration involves thinning of the retina that occurs over time. Here we performed an immunohistological study of tissue sections of human peripheral retinal lattice degeneration to investigate if retinal pigment epithelium (RPE) cells are involved in the pathogenesis of this condition. In two cases of retinal detachment with a large tear that underwent vitreous surgery, retinal lattice degeneration tissue specimens were collected during surgery. In the obtained specimens, both whole mounts and horizontal section slices were prepared, and immunostaining was then performed with hematoxylin and antibodies against glial fibrillary acidic protein (GFAP), RPE-specific protein 65 kDa (RPE65), pan-cytokeratin (pan-CK), and CK18. Hematoxylin staining showed no nuclei in the center of the degenerative lesion, thus suggesting the possibility of the occurrence of apoptosis. In the degenerative lesion specimens, GFAP staining was observed in the center, RPE65 staining was observed in the slightly peripheral region, and pan-CK staining was observed in all areas. However, no obvious CK18 staining was observed. In a monkey retina used as the control specimen of a normal healthy retina, no RPE65 or pan-CK staining was observed in the neural retina. Our findings suggest that migration, proliferation, and differentiation of RPE cells might be involved in the repair of retinal lattice degeneration.

Horizontal Hippocampal Slices of the Mouse Brain.

The hippocampus is a highly organized structure in the brain that is a part of the limbic system and is involved in memory formation and consolidation as well as the manifestation of severe brain disorders, including Alzheimer's disease and epilepsy. The hippocampus receives a high degree of intra- and inter-connectivity, securing a proper communication with internal and external brain structures. This connectivity is accomplished via different informational flows in the form of fiber pathways. Brain slices are a frequently used methodology when exploring neurophysiological functions of the hippocampus. Hippocampal brain slices can be used for several different applications, including electrophysiological recordings, light microscopic measurements as well as several molecular biological and histochemical techniques. Therefore, brain slices represent an ideal model system to assess protein functions, to investigate pathophysiological processes involved in neurological disorders as well as for drug discovery purposes. There exist several different ways of slice preparations. Brain slice preparations with a vibratome allow a better preservation of the tissue structure and guarantee a sufficient oxygen supply during slicing, which present advantages over the traditional use of a tissue chopper. Moreover, different cutting planes can be applied for vibratome brain slice preparations. Here, a detailed protocol for a successful preparation of vibratome-cut horizontal hippocampal slices of mouse brains is provided. In contrast to other slice preparations, horizontal slicing allows to keep the fibers of the hippocampal input path (perforant path) in a fully intact state within a slice, which facilitates the investigation of entorhinal-hippocampal interactions. Here, we provide a thorough protocol for the dissection, extraction, and acute horizontal slicing of the murine brain, and discuss challenges and potential pitfalls of this technique. Finally, we will show some examples for the use of brain slices in further applications.

Multi-View Spectral Clustering Tailored Tensor Low-Rank Representation

This paper explores the problem of multi-view spectral clustering (MVSC) based on tensor low-rank modeling. Unlike the existing methods that all adopt an off-the-shelf tensor low-rank norm without considering the special characteristics of the tensor in MVSC, we design a novel structured tensor low-rank norm tailored to MVSC. Specifically, we explicitly impose a symmetric low-rank constraint and a structured sparse low-rank constraint on the frontal and horizontal slices of the tensor to characterize the intra-view and inter-view relationships, respectively. Moreover, the two constraints could be jointly optimized to achieve mutual refinement. On basis of the novel tensor low-rank norm, we formulate MVSC as a convex low-rank tensor recovery problem, which is then efficiently solved with an augmented Lagrange multiplier-based method iteratively. Extensive experimental results on seven commonly used benchmark datasets show that the proposed method outperforms state-of-the-art methods to a significant extent. Impressively, our method is able to produce perfect clustering. In addition, the parameters of our method can be easily tuned, and the proposed model is robust to different datasets, demonstrating its potential in practice. The code is available at <uri xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">https://github.com/jyh-learning/MVSC-TLRR</uri> .