Miracle-dz/UniFAR-FTUs huggingface dataset:
Increased Low-Frequency Oscillation Amplitude of Sensorimotor Cortex Associated with the Severity of Structural Impairment in Cervical Myelopathy

Decreases in metabolites and increased motor-related, but decreased sensory-related activation of the sensorimotor cortex (SMC) have been observed in patients with cervical myelopathy (CM) using advanced MRI techniques. However, the nature of intrinsic neuronal activity in the SMC, and the relationship between cerebral function and structural damage of the spinal cord in patients with CM are not fully understood. The purpose of this study was to assess intrinsic neuronal activity by calculating the regional amplitude of low frequency fluctuations (ALFF) using resting-state functional MRI (rs-fMRI), and correlations with clinical and imaging indices. Nineteen patients and 19 age- and sex-matched healthy subjects underwent rs-fMRI scans. ALFF measurements were performed in the SMC, a key brain network likely to impaired or reorganized patients with CM. Compared with healthy subjects, increased amplitude of cortical low-frequency oscillations (LFO) was observed in the right precentral gyrus, right postcentral gyrus, and left supplementary motor area. Furthermore, increased z-ALFF values in the right precentral gyrus and right postcentral gyrus correlated with decreased fractional anisotropy values at the C2 level, which indicated increased intrinsic neuronal activity in the SMC corresponding to the structural impairment in the spinal cord of patients with CM. These findings suggest a complex and diverging relationship of cortical functional reorganization and distal spinal anatomical compression in patients with CM and, thus, add important information in understanding how spinal cord integrity may be a factor in the intrinsic covariance of spontaneous low-frequency fluctuations of BOLD signals involved in cortical plasticity.
Adaptive load distribution over multipath in NEPLS networks

The emergence of multiprotocol label switching (MPLS) with its efficient support of explicit routing provides basic mechanisms for facilitating traffic engineering. Exploiting this capability of MPLS, we propose an adaptive multipath traffic engineering mechanism named LDM (load distribution over multipath). The main goal of LDM is to enhance the network utilization as well as the network performance by adaptively splitting traffic load among multiple paths. LDM takes pure dynamic approach not requiring any a priori traffic load statistics. Routing decisions are made at the flow level, and traffic proportioning reflects both the length and the load of a path. LDM also dynamically selects a few good label switched paths (LSPs) according to the state of the entire network. We use simulation to compare the performance of LDM with the performance of several representative dynamic load distribution approaches as well as the traditional static shortest path only routing. The numerical results show that LDM outperforms the compared approaches in both the blocking ratio as well as the performance of the accepted traffic flows.
Efficient Distributed Approach for Density-Based Clustering

Nowadays, large bodies of data in different domains are collected and stored. An efficient extraction of useful knowledge from these data becomes a huge challenge. This leads to the need for developing distributed data mining techniques. However, only a few research concerns distributed clustering for analysing large, heterogeneous and distributed datasets. Besides, current distributed clustering approaches are normally generating global models by aggregating local results that would lose important knowledge. In this paper, we present a new distributed data mining approach where local models are not directly merged to build the global ones. Preliminary results of this algorithm are also discussed
SPATIAL AND TEMPORAL FACTORS AFFECTING COEXISTENCE AMONG SEXUAL AND CLONAL FORMS OF POECILIOPSIS

We examined spatial and seasonal factors affecting coexistence of closely related sexual and asexual fishes of the genus Poeciliopsis living in two ecologically distinct stream habitats. Stream order and productivity influenced frequencies of these fish, and local habitat patchiness contributed strongly to spatial segregation. The magnitude and direction of local segregation was unaffected by striking seasonal variation in one stream. For the second stream, the relative contributions of local, geographical, and seasonal components of spatial variation were assessed through estimation of variance components. Spatial segregation at the smallest scale accounted for the largest proportion of variance in the distribution of species and clones.
Temporal Dynamics of Visual Attention Measured with Event-Related Potentials

How attentional modulation on brain activities determines behavioral performance has been one of the most important issues in cognitive neuroscience. This issue has been addressed by comparing the temporal relationship between attentional modulations on neural activities and behavior. Our previous study measured the time course of attention with amplitude and phase coherence of steady-state visual evoked potential (SSVEP) and found that the modulation latency of phase coherence rather than that of amplitude was consistent with the latency of behavioral performance. In this study, as a complementary report, we compared the time course of visual attention shift measured by event-related potentials (ERPs) with that by target detection task. We developed a novel technique to compare ERPs with behavioral results and analyzed the EEG data in our previous study. Two sets of flickering stimulus at different frequencies were presented in the left and right visual hemifields, and a target or distracter pattern was presented randomly at various moments after an attention-cue presentation. The observers were asked to detect targets on the attended stimulus after the cue. We found that two ERP components, P300 and N2pc, were elicited by the target presented at the attended location. Time-course analyses revealed that attentional modulation of the P300 and N2pc amplitudes increased gradually until reaching a maximum and lasted at least 1.5 s after the cue onset, which is similar to the temporal dynamics of behavioral performance. However, attentional modulation of these ERP components started later than that of behavioral performance. Rather, the time course of attentional modulation of behavioral performance was more closely associated with that of the concurrently recorded SSVEPs analyzed. These results suggest that neural activities reflected not by either the P300 or N2pc, but by the SSVEPs, are the source of attentional modulation of behavioral performance.
Experimental and numerical analyses of the shimming effect on bolted joints with nonuniform gaps

In order to investigate the effect of shim compensation for nonuniform gaps in aircraft assembly, the influence of the shims with different material and parameters on bolted joints is studied in this paper. According to the real material and assembly conditions of the aircraft joint structures, the specimen and experiment are designed to obtain the tensile performance of the joint structures with different shims. A three-dimensional finite element model, which incorporates the Johnson–Cook material property of the alloys, traction-separation law of liquid shims, contact relationships between the joint elements, and boundary conditions of the tensile process, is established with the specimen configurations. After validating through comparing with the experimental results, the modeling method is adopted to simulate the tensile response of the bolted joints with shims. Furthermore, both the influence of the shim material and thickness on the mechanical behaviors of bolted joints is investigated in detail. Shims can considerably reduce the assembly stress of joint structures and improve the joint stiffness and load capacity, and this effect is more remarkable with the increase of gap values. Liquid shims improve the joint stiffness due to its cohesive ability, while solid shims improve the joint load capacity. Hybrid shims possess a composite shimming effect of liquid and solid shims. Whatever the shim material is applied, the joint stiffness and strength drop with the growth of shim thickness, so strict deviation control method should be taken to ensure the assembly gaps as small as possible. The research results enhance the knowledge of shimming effect on joint structures, and thus offer positive guidance for practical application in aircraft assembly.
A comparison of thiolated and disulfide-crosslinked polyethylenimine for nonviral gene delivery.

Branched polyethylenimine (25 kDa) is thiolated and compared with redox-sensitive crosslinked derivatives. Both polymers thiol contents are assessed; the thiolated polymers have 390-2300 mmol SH groups/mol, whereas the crosslinked polymers have lower thiol contents. Cytotoxicity assays show that both modified polymers give lower hemolysis than unmodified PEI. Increased thiol content increases gene transfer efficiency but also elevates cytotoxicity. Crosslinking improves plasmid DNA condensation and enhances transfection efficiency, but extensive crosslinking overstabilizes the polyplexes and decreases transfection, emphasizing the need to balance polyplex stabilization and unpacking. Thus, at low levels of crosslinking, 25 kDa PEI can be an efficient redox-sensitive carrier system.
Compensation for cranial spill‐in into the cerebellum improves quantitation of striatal dopamine D2/3 receptors in rats with prolonged [18F]‐DMFP infusions

The condition of steady‐state receptor binding in positron emission tomography (PET) studies is best obtained through the use of a bolus plus steady‐infusion paradigm. This is a particularly important consideration in the context of in vivo competition studies, where a pharmacological challenge can be administered during the interval of steady‐state ligand binding, as in the case of [11C]‐raclopride studies with amphetamine challenge. However, the short half‐life of 11C imposes limits on the practical duration of constant infusions. Therefore, we chose to test [18F]‐DMFP as a tracer for dopamine D2/3 receptors in rat striatum in the paradigm. Using a conventional bolus injection, the [18F]‐DMFP BPND was 3.8 in striatum of anesthetized rats. When followed by a constant infusion, we obtained quasi‐stable BPND estimates of 4.5 within an interval of 45 min. During infusions lasting up to 4 h, BPND declined progressively. This seemed due to the progressive spill‐in of radioactivity from the cranium to the cerebellum reference region, despite optimized iterative reconstruction of the images. Therefore, we propose a new concept of compensation for this spill‐in effect using pharmacokinetic considerations, without requiring high‐resolution anatomical images. Challenge with amphetamine (1 and 4 mg/kg) evoked an ∼25% reduction in BPND. There was no clear evidence of dose‐dependence in the striatal‐binding changes, despite the considerably greater physiological effect, as documented by ECG. Thus, the general applicability of the bolus plus infusion method with [18F]‐DMFP for small animal studies is impeded by the substantial labeling of the cranium. The cranial uptake was linear, indicating first‐order kinetics for the enzymatic defluorination of the tracer. Based on this phenomenon, we developed an analytic method compensating for the effects of progressive cranial labeling on the estimation of specific binding in striatum. Synapse, 2012. © 2012 Wiley Periodicals, Inc.
Two Closely Spaced Tyrosines Regulate NFAT Signaling in B Cells via Syk Association with Vav

ABSTRACT Activated Syk, an essential tyrosine kinase in B cell signaling, interacts with Vav guanine nucleotide exchange factors and regulates Vav activity through tyrosine phosphorylation. The Vav SH2 domain binds Syk linker B by an unusual recognition of two closely spaced Syk tyrosines: Y342 and Y346. The binding affinity is highest when both Y342 and Y346 are phosphorylated. An investigation in B cells of the dependence of Vav phosphorylation and NFAT activation on phosphorylation of Y342 and Y346 finds that cellular response levels match the relative binding affinities of the Vav1 SH2 domain for singly and doubly phosphorylated linker B peptides. This key result suggests that the uncommon recognition determinant of these two closely spaced tyrosines is a limiting factor in signaling. Interestingly, differences in affinities for binding singly and doubly phosphorylated peptides are reflected in the on rate, not the off rate. Such a control mechanism would be highly effective for regulating binding among competing Syk binding partners. The nuclear magnetic resonance (NMR) structure of Vav1 SH2 in complex with a doubly phosphorylated linker B peptide reveals diverse conformations associated with the unusual SH2 recognition of two phosphotyrosines. NMR relaxation indicates compensatory changes in loop fluctuations upon binding, with implications for nonphosphotyrosine interactions of Vav1 SH2.
The effects of CaCO3 on the properties of PCL wood-plastic composites

The effects of CaCO3 on the properties of PCL wood-plastic composites were studied in this paper. The strength and the melt flow rate of the composites increased first and then decreased with the content of CaCO3, and up to maximum while the content of CaCO3 is 30%. Gaps and holes could be seen from the SEM figure in the composites when the content of CaCO3 is more than 30%. Above all, the best content of CaCO3 in the composites is 30%.
Magnetic Resonance Imaging of the Rat Retina

The retina is a thin layer of tissue lining the back of the eye and is primarily responsible for sight in vertebrates. The neural retina has a distinct layered structure with three dense nuclear layers, separated by plexiform layers comprising of axons and dendrites, and a layer of photoreceptor segments. The retinal and choroidal vasculatures nourish the retina from either side, with an avascular layer comprised largely of photoreceptor cells. Diseases that directly affect the neural retina like retinal degeneration as well as those of vascular origin like diabetic retinopathy can lead to partial or total blindness. Early detection of these diseases can potentially pave the way for a timely intervention and improve patient prognosis. Current techniques of retinal imaging rely mainly on optical techniques, which have limited depth resolution and depend mainly on the clarity of visual pathway. Magnetic resonance imaging is a versatile tool that has long been used for anatomical and functional imaging in humans and animals, and can potentially be used for retinal imaging without the limitations of optical methods. The work reported in this thesis involves the development of high resolution magnetic resonance imaging techniques for anatomical and functional imaging of the retina in rats. The rats were anesthetized using isoflurane, mechanically ventilated and paralyzed using pancuronium bromide to reduce eye motion during retinal MRI. The retina was imaged using a small, single-turn surface coil placed directly over the eye. The several physiological parameters, like rectal temperature, fraction of inspired oxygen, end-tidal CO2, were continuously monitored in all rats. MRI parameters like T1, T2, and the apparent diffusion coefficient of water molecules were determined from the rat retina
Delay and Throughput Optimal Scheduling for OFDM Broadcast Channels

In this paper a scheduling policy is presented which minimizes the average delay of the users. The scheduling scheme is investigated both by analysis and simulations carried out in the context of Orthogonal Frequency Division Multiplexing (OFDM) broadcast channels (BC). First the delay optimality is obtained for a static scenario providing solutions for specific subproblems, then the analysis is carried over to the dynamic scheme. Furthermore auxiliary tools are given for proving throughput optimality. Finally simulations show the superior performance of the presented scheme.
Nanodiamond in optical fibre.

Faculty of Sciences School of Chemistry & Physics Doctor of Philosophy by Matthew Ryan Henderson Diamond, prized as both a gemstone and a cutting and polishing material, has recently been recognised for another remarkable property, a host of optically active colour centre defects. With the rise of interest in these colour centres, due to the unique optical properties, comes a need for interfacing with other optical platforms. Recent advances have attempted to fabricate optical structures from the diamond itself, or to combine these colour centres with the well-known fabrication techniques of other materials by placing nanodiamond crystals on the surface of other structures, such as microdisks, microspheres, and optical fibres. This thesis presents a new approach to this integration by demonstrating the fabrication of a hybrid nanodiamond-glass material. This technique embeds the nanodiamond within the optical structure, offering interaction with the bound optical fields, protection, and ease of fabrication. A range of optical structures has previously been fabricated from the chosen glass, tellurite, and fabrication of an optical fibre is demonstrated here. Also presented is the derivation of a model describing coupling of an emitter to an optical fibre. While used here to investigate coupling of diamond colour centres to the optical fibre modes, it is more generally applicable to any emitter. These results show the first steps of a new approach to diamond integrated photonics.
Temporal variability predicts the magnitude of between-group attentional blink differences in developmental dyslexia: a meta-analysis

Background. Here we report on a meta-analysis of the between-group main effect (Group Difference) noted in the attentional blink (AB) research focused on specific reading impairment, commonly referred to as developmental dyslexia. The AB effect relates to a limitation in the allocation of attention over time and is examined in a dual-target rapid serial visual presentation (RSVP) paradigm. When the second target appears in close temporal proximity to the first target, the second target is reported less accurately. Method. A Web of Science search with terms “attentional blink” & dyslexia returned 13 AB experiments (11 papers) conducted with developmental dyslexia. After exclusions, 12 experiments were included in the meta-analysis. The main pattern of performance from those experiments was lower overall accuracy in groups of individuals with dyslexia relative to typically reading peers; that is, a between-group main effect. This meta-analysis examined the size of the Group Difference in relation to temporal and task-set related features, which differed between and within experiments. Results. Random effects modelling indicated a significant Group Difference of −0.74 standard deviation units, 95% CI [−. 96, −. 52], p < . 001 (excluding one anomalous result): implicating significantly poorer overall dual-target performance in dyslexic readers. Meta-regression analyses indicated two variables related to the Group Difference; pre-RSVP time and temporal variability of the second target relative to the first target within the RSVP. Discussion. It is suggested that the endogenous engagement of the temporal features of task-set is slower or disrupted in developmental dyslexia.
Automatic identification of perceptually important regions in an image

We present a method for automatically determining the perceptual importance of different regions in an image. The algorithm is based on human visual attention and eye movement characteristics. Several features known to influence human visual attention are evaluated for each region of a segmented image to produce an importance value for each factor and region. These are combined to produce an Importance Map, which classifies each region of the image in relation to its perceptual importance. Results shown indicate that the calculated Importance Maps correlate well with human perception of visually important regions. The Importance Maps can be used in a variety of applications, including compression, machine vision, and image databases. Our technique is computationally efficient and flexible, and can easily be extended to specific applications.
A Robust Method for Pulse Peak Determination in a Digital Volume Pulse Waveform With a Wandering Baseline

This paper presents a robust method for pulse peak determination in a digital volume pulse (DVP) waveform with a wandering baseline. A proposed new method uses a modified morphological filter (MMF) to eliminate a wandering baseline signal of the DVP signal with minimum distortion and a slope sum function (SSF) with an adaptive thresholding scheme to detect pulse peaks from the baseline-removed DVP signal. Further in order to cope with over-detected and missed pulse peaks, knowledge based rules are applied as a postprocessor. The algorithm automatically adjusts detection parameters periodically to adapt to varying beat morphologies and fluctuations. Compared with conventional methods (highpass filtering, linear interpolation, cubic spline interpolation, and wavelet adaptive filtering), our method performs better in terms of the signal-to-error ratio, the computational burden (0.125 seconds for one minute of DVP signal analysis with the Intel Core 2 Quad processor @ 2.40 GHz PC), the true detection rate (97.32% with an acceptance level of 4 ms ) as well as the normalized error rate (0.18%). In addition, the proposed method can detect true positions of pulse peaks more accurately and becomes very useful for pulse transit time (PTT) and pulse rate variability (PRV) analyses.
Laminin receptor-targeted etoposide loaded polymeric micelles: a novel approach for the effective treatment of tumor metastasis

Background: Tumor-targeted delivery is a desirable approach to improve therapeutic outcome of anticancer drug due to enhanced efficacy and reduced toxicity. Purpose: The present study was aimed to target laminin receptor over-expressed tumor cells using YIGSR (Tyr-Ile-Gly-Ser-Arg) conjugated etoposide loaded micelles in the treatment of metastasis. Methods: YIGSR conjugated micelles prepared using synthesized carboxyl and methoxy terminated poly(ethylene glycol)-b-poly(ϵ-caprolactone) block copolymers were evaluated for it efficacy against highly metastatic B16F10 cell lines conducting cytotoxicity, colony formation, cell migration, cellular uptake and flow cytometry studies. The in-vivo antimetastatic effect of micelles was evaluated using experimental metastatic model on C57BL/6 mice. Results: YIGSR conjugated micelles of particle size 45.2 ± 3.77 nm and zeta potential of−5.7 ± 1.3 mV demonstrated enhanced cytotoxicity and cellular uptake with significant reduction in colony formation and cell migration activities compared to non-conjugated micelles. Furthermore, a markedly inhibition in lung colony formation was observed with these micelles. Discussion: An enhanced cellular internalization of YIGSR conjugated micelles due to laminin receptor based endocytosis resulted in to higher cytotoxicity as well as antimetastatic effect against highly metastatic B16F10 cells. Conclusion: These studies indicate that YIGSR conjugated nanocarrier can be a promising approach in the treatment of tumor metastasis.