Miracle-dz/UniFAR-FTUs huggingface dataset:
Control of Neuronal Excitability by Calcium Binding Proteins: A New Mathematical Model for Striatal Fast-Spiking Interneurons

Calcium binding proteins, such as parvalbumin (PV), are abundantly expressed in distinctive patterns in the central nervous system but their physiological function remains poorly understood. Notably, at the level of the striatum, where PV is only expressed in the fast-spiking (FS) interneurons. FS interneurons form an inhibitory network modulating the output of the striatum by synchronizing medium-sized spiny neurons (MSN). So far the existing conductance-based computational models for FS neurons did not allow the study of the coupling between PV concentration and electrical activity. In the present paper, we propose a new mathematical model for the striatal FS interneurons that includes apamin-sensitive small conductance Ca2+-dependent K+ channels (SK) and the presence of a calcium buffer. Our results show that a variation in the concentration of PV can modulate substantially the intrinsic excitability of the FS interneurons and therefore may be involved in the information processing at the striatal level.
On the Advantages of a Systematic Inspection for Evaluating Hypermedia Usability

It is indubitable that usability inspection of complex hypermedia is still an "art," in the sense that a great deal is left to the skills, experience, and ability of the inspectors. Training inspectors is difficult and often quite expensive. The Systematic Usability Evaluation (SUE) inspection technique has been proposed to help usability inspectors share and transfer their evaluation know-how, to simplify the hypermedia inspection process for newcomers, and to achieve more effective and efficient evaluation results. SUE inspection is based on the use of evaluation patterns, called abstract tasks, which precisely describe the activities to be performed by evaluators during inspection. This article highlights the advantages of this inspection technique by presenting its empirical validation through a controlled experiment. Two groups of novice inspectors were asked to evaluate a commercial hypermedia CD-ROM by applying the SUE inspection or traditional heuristic evaluation. The comparison was based on three major dimensions: effectiveness, efficiency, and satisfaction. Results indicate a clear advantage of the SUE inspection over the traditional inspection on all dimensions, demonstrating that abstract tasks are efficient tools to drive the evaluator's performance.
Quantifying boron and phosphorous dopant concentrations in silicon from photoluminescence spectroscopy at 79 K

Photoluminescence spectroscopy at 79 K is shown to provide an alternative, non‐destructive characterisation method for quantifying the boron and phosphorous dopant concentrations in silicon. The dopant concentrations are revealed by the photoluminescence intensity ratios of the dopant‐related features to the band‐to‐band recombination peaks. The intensity ratio is found to be insensitive to the excitation power in a wide range of 0.3 W cm−2–100 kW cm−2. Calibration curves for boron and phosphorous in silicon are presented for [B] below 5 × 1017 cm−3 and [P] below 8 × 1016 cm−3.
Local Ambiguity Function Shaping via Unimodular Sequence Design

This letter focuses on the local ambiguity function shaping through unimodular sequence design. An accelerated iterative sequential optimization (AISO) algorithm is proposed to minimize the average value of the weighted integrated sidelobe level (WISL) over specific Doppler bins and range bins of interest. We evaluate the effectiveness of the AISO algorithm in terms of its achieved WISL and computational complexity in comparison with the gradient method via numerical examples. The capability of using the design to detect high-speed targets is also evaluated.
Distinguishing between activated and nonactivated eosinophils by AC impedance measurements

A cellular electrical impedance device which can detect the activated state of eosinophils has been developed and tested. This impedance device consists of a small gold electrode (50 /spl mu/m/spl times/50 /spl mu/m) and a large gold electrode (1.5 cm/spl times/0.5 cm) on a glass substrate, and it was fabricated by standard photolithographic techniques. Eosinophils, which belong to the granulocytic class of white blood cells, exhibit different physical properties when they change from the nonactivated state to the activated state. Hypothetically, these changes should correspond to a change in the measured electrical impedance. In this paper, data from the measured electrical impedance of eosinophils is presented. The measurements show that the average impedance of the activated eosinophils is 26% lower than the average impedance of the nonactivated eosinophils. Statistical analysis of the measured data shows that there is a significant difference between the measured impedances of activated and nonactivated eosinophils.
Blind Compressed Sensing

The fundamental principle underlying compressed sensing is that a signal, which is sparse under some basis representation, can be recovered from a small number of linear measurements. However, prior knowledge of the sparsity basis is essential for the recovery process. This work introduces the concept of blind compressed sensing, which avoids the need to know the sparsity basis in both the sampling and the recovery process. We suggest three possible constraints on the sparsity basis that can be added to the problem in order to guarantee a unique solution. For each constraint, we prove conditions for uniqueness, and suggest a simple method to retrieve the solution. We demonstrate through simulations that our methods can achieve results similar to those of standard compressed sensing, which rely on prior knowledge of the sparsity basis, as long as the signals are sparse enough. This offers a general sampling and reconstruction system that fits all sparse signals, regardless of the sparsity basis, under the conditions and constraints presented in this work.
Object Detection in Real Images

Object detection and recognition are important problems in computer vision. Since these problems are meta-heuristic, despite a lot of research, practically usable, intelligent, real-time, and dynamic object detection/recognition methods are still unavailable. We propose a new object detection/recognition method, which improves over the existing methods in every stage of the object detection/recognition process. In addition to the usual features, we propose to use geometric shapes, like linear cues, ellipses and quadrangles, as additional features. The full potential of geometric cues is exploited by using them to extract other features in a robust, computationally efficient, and less meta-heuristic manner. We also propose a new hierarchical codebook, which provides good generalization and discriminative properties. The codebook enables fast multi-path inference mechanisms based on propagation of conditional likelihoods, that make it robust to occlusion and noise. It has the capability of dynamic learning. We also propose a new learning method that has generative and discriminative learning capabilities, does not need large and fully supervised training dataset, and is capable of online learning. The preliminary work of detecting geometric shapes in real images has been completed. This preliminary work is the focus of this report. Future path for realizing the proposed object detection/recognition method is also discussed in brief.
A uniform asymptotic turning point theory for second order linear ordinary differential equations

The method of Cherry for obtaining uniform asymptotic solutions for a second order linear ordinary differential equation with a single turning point of first order is formally extended to the case where the equation has an arbitrary number of turning points of various orders. This follows a recent extension by Lynn and Keller of Langer's method to deal with the aforementioned more general problem.
Replication strategies for reliable decentralised storage

Distributed hash tables (DHTs) can be used as the basis of a resilient lookup service in unstable environments: local routing tables are updated to reflected changes in the network; efficient routing can be maintained in the face of participant node failures. This fault-tolerance is an important aspect of modern, decentralised data storage solutions. In architectures that employ DHTs, the choice of algorithm for data replication and maintenance can have a significant impact upon performance and reliability. This paper presents a comparative analysis of replication algorithms for architectures based upon a specific design of DHT. It presents also a novel maintenance algorithm for dynamic replica placement, and considers the reliability of the resulting designs at the system level. The performance of the algorithms is examined using simulation techniques; significant differences are identified in terms of communication costs and latency.
Liquid-in-gas droplet microfluidics; experimental characterization of droplet morphology, generation frequency, and monodispersity in a flow-focusing microfluidic device

Microfluidic techniques for production of uniform droplets usually rely on the use of two immiscible liquids (e.g. water-in-oil emulsions). It has been shown recently that a continuous gas flow instead of a second liquid carrier can be used as an alternative approach in droplet microfluidics. In this work we experimentally investigate the generation of liquid water droplets within air in flow-focusing configurations. Over a wide range of flow conditions we identify six distinct flow regimes inside the microchannel: Co-flowing, Threading, Plugging, Dripping, Multi-Satellite Formation, and Jetting. Flow regimes and their transitions are plotted and characterized based on the Weber number (We) of the system. We further investigate the impact of liquid microchannel size on the flow maps. Generation frequency, morphology, and monodispersity of the droplets are characterized in more detail in the Dripping regime. Generation frequency can be related to the product of the liquid and gas flow rates. However, droplet morphology (length and width) is more dependent on the gas flow rate. We demonstrate the production of monodisperse droplets (d < 100 µm and σ/d < 5 %) up to kHz formation rates in liquid-gas microfluidic systems for the first time. The results of this work provide practical and useful guidelines for precise, oil-free delivery of ultra-small volumes of fluid which can be integrated in lab-on-a-chip systems for a variety of applications in biochemical research and material synthesis.
Estimating the relative usability of two interfaces: heuristic, formal, and empirical methods compared

Two alternative user interface designs were subjected to user testing to measure user performance in a database query task. User performance was also estimated heuristically in three different ways and by use of formal GOMS modelling. The estimated values for absolute user performance had very high variability, but estimates of the relative advantage of the fastest interface were less variable. Choosing the fastest of the two designs would have a net present value more than 1,000 times the cost of getting the estimates. A software manager would make the correct choice every time in our case study if decisions were based on at least three independent estimates. User testing was 4.9 times as expensive as the cheapest heuristic method but provided better performance estimates.
Tailoring Material and Mechanochemical Responses with Microstructure

Tailoring Material and Mechanochemical Responses with Microstructure Morgan Bassford Chair of the Supervisory Committee: Assistant Professor Nicholas Boechler Mechanical Engineering The objectives of this project were twofold: (i) to develop a methodology for tailoring the nonlinear elastic response of a 2D lattice material through designed microstructural geometric nonlinearities; and (ii) to show that activation of mechanophores (such as spiropyran) can be similarly manipulated through lattice geometry. Exploring this space may lead to new materials that can be engineered to yield prescribed mechanical and chemical loading responses, such as dissipating or focusing energy when struck or triggering chemical reactions under certain loads. The ability to customize these properties in a systematic way could facilitate the design and fabrication of advanced energetic, impact-mitigating, self-healing or self-reinforcing materials. In this thesis, a heuristic exploration of 2D nonlinear lattices was conducted, in which lattices were designed, modeled in COMSOL, and then 3D printed and quasi-statically tested to validate simulation results. A lattice that softens under compression, as well as two that stiffen under compression (using contact and non-contact based mechanisms) were created. A nonlinear topology optimization scheme using a MATLAB genetic algorithm and COMSOL Finite Element Analysis (FEA) was also created to find structures to match prescribed forcedisplacement curves: however, this topology optimizer struggled finding non-unique solutions and poorly connected structures. Spiropyran was embedded in PDMS and studied in quasistatic and dynamic compression. It was found that spiropyran activated at compressive strains greater than 0.7 at both high and low strain rates and in less than 8 ms during dynamic tests. Finally, spiropyran was embedded in PCL and printed into an oval pore lattice shape; these samples, as well as control (non-lattice, bulk) samples were subjected to tensile tests. As spiropyran activation in the lattices was observed prior to activation in the control samples, these experiments suggest that microstructure can amplify mechanochemical response.
Cathepsin S Regulates Class II MHC Processing in Human CD4+ HLA-DR+ T Cells1

Although it has long been known that human CD4+ T cells can express functional class II MHC molecules, the role of lysosomal proteases in the T cell class II MHC processing and presentation pathway is unknown. Using CD4+ T cell clones that constitutively express class II MHC, we determined that cathepsin S is necessary for invariant chain proteolysis in T cells. CD4+HLA-DR+ T cells down-regulated cathepsin S expression and activity 18 h after activation, thereby ceasing nascent class II MHC product formation. This blockade resulted in the loss of the invariant chain fragment CLIP from the cell surface, suggesting that—like professional APC—CD4+ HLA-DR+ cells modulate self-Ag presentation as a consequence of activation. Furthermore, cathepsin S expression and activity, and concordantly cell surface CLIP expression, was reduced in HLA-DR+ CD4+ T cells as compared with B cells both in vitro and ex vivo.
Limited oxygen diffusion accelerates fatigue development in mouse skeletal muscle

Isolated whole skeletal muscles fatigue more rapidly than isolated single muscle fibres. We have now employed this difference to study mechanisms of skeletal muscle fatigue. Isolated whole soleus and extensor digitorum longus (EDL) muscles were fatigued by repeated tetanic stimulation while measuring force production. Neither application of 10 mm lactic acid nor increasing the [K+] of the bath solution from 5 to 10 mm had any significant effect on the rate of force decline during fatigue induced by repeated brief tetani. Soleus muscles fatigued slightly faster during continuous tetanic stimulation in 10 mm[K+]. Inhibition of mitochondrial respiration with cyanide resulted in a faster fatigue development in both soleus and EDL muscles. Single soleus muscle fibres were fatigued by repeated tetani while measuring force and myoplasmic free [Ca2+] ([Ca2+]i). Under control conditions, the single fibres were substantially more fatigue resistant than the whole soleus muscles; tetanic force at the end of a series of 100 tetani was reduced by about 10% and 50%, respectively. However, in the presence of cyanide, fatigue developed at a similar rate in whole muscles and single fibres, and tetanic force at the end of fatiguing stimulation was reduced by ∼80%. The force decrease in the presence of cyanide was associated with a ∼50% decrease in tetanic [Ca2+]i, compared with an increase of ∼20% without cyanide. In conclusion, lactic acid or [K+] has little impact on fatigue induced by repeated tetani, whereas hypoxia speeds up fatigue development and this is mainly due to an impaired Ca2+ release from the sarcoplasmic reticulum.
Upscale and downscale energy transfer over the tropical Pacific revealed by scatterometer winds

The direction of the energy cascade in the mesoscales of atmospheric turbulence is investigated using near-surface winds over the tropical Pacific measured by satellite scatterometers SeaWinds (QuikSCAT) and ASCAT (MetOp-A). The tropical Pacific was subdivided into nine regions, classified as rainy or dry. Longitudinal third-order along-track structure functions DLLLa and skewness SLa were calculated as a function of separation r for each region and month during the period November 2008 to October 2009. We find that the results support both downscale and upscale interpretations, depending on region and month. The results indicate that normally energy cascades downscale, but cascades upscale over the cold tongue in the cold season and over the west Pacific in summer months. An explanation is offered based on the heating or cooling of the air by the underlying sea surface temperature. It is also found that the signature of intermittent small-scale (<100 km) events could be identified in graphs of SLa, implying that this diagnostic may be useful in the studies of tropical disturbances.
Interactive Proofs For Quantum Computations

The widely held belief that BQP strictly contains BPP raises fundamental questions: Upcoming generations of quantum computers might already be too large to be simulated classically. Is it possible to experimentally test that the se systems perform as they should, if we cannot efficiently comp ute predictions for their behavior? Vazirani has asked [Vaz07]: If computing predictions for Quantum Mechanics requires exponential resources, is Quantum Mechanics a falsifiable theory? In cryptographic settings, an untruste d future company wants to sell a quantum computer or perform a delegated quantum computation. Can the customer be convinced of correctness without the ability to compare results to predictions? To provide answers to these questions, we define Quantum Prov er Interactive Proofs (QPIP). Whereas in standard Interactive Proofs [GMR85] the prover is computationally unbounded, here our prover is in BQP, representing a quantum computer. The verifier models our current computati onal capabilities: it is a BPP machine, with access to few qubits. Our main theorem can be roughly stated as: ”Any language in BQP has a QPIP, and moreover, a fault tolerant one”. We provide two proofs. The simpler one uses a new (possibly of independent interest) quantum authentication scheme (QAS) based on random Clifford elements. This QPIP however, is not fault tolerant. Our � �
Automated 3D segmentation of hippocampus based on active appearance model of brain MR images for the early diagnosis of Alzheimer's disease.

AIM To investigate the hippocampal regional deformation modes by means of a novel method of automatic segmentation for discriminating between Alzheimer's disease (AD) and normal aging; and to further provide the effective evidence for the early diagnosis of AD. METHODS Twenty AD patients and sixty healthy volunteers were included in this retrospective study. High-resolution structural volumetric images were obtained on a 3.0 T MR imaging system. Data were processed to create three-dimensional (3D) active appearance model (AAM) of hippocampus. Automatic recognition and 3D segmentation were carried out on both sides of the hippocampus in brain MR images of individuals with this model, and the hippocampal statistical shape model was established for AD group and control group. Student's t test was used to identify whether there was difference between AD group and control group in the hippocampal regional deformation detected by automatic segmentation, and to compare whether there was difference between the automated segmentation and the manual tracing for quantifying hippocampal volumes on left/right side of the same sex group of healthy volunteers and if there was genderwise difference. Pearson's Correlation test was employed to determine whether there was a correlation between automated segmentation and manual tracing for quantifying hippocampal volumes. RESULTS No significant difference was detected between automated segmentation and manual tracing for quantifying hippocampal volumes on left/right side of the same sex group of healthy volunteers (P>0.05). Further there was no significant genderwise difference (P>0.05). A very strong positive correlation existed between both methods for quantifying hippocampal volumes (denoted R(2) near 1.0, P<0.001). Noticeable atrophy of bilateral hippocampal head was found among twenty patients with AD through statistical shape model compared with control group (P<0.05), especially on the left where inward-deformation was significantly found. CONCLUSION This novel method of automated segmentation of the hippocampus based on AAM has been found to be reliable and accurate in our study, which may be an alternative to manual segmentation. The featured atrophy of hippocampal head can be regarded as an important biomarker for the early diagnosis of AD.
A hybrid strategy to solve the forward kinematics problem in parallel manipulators

A parallel manipulator is a closed kinematic structure with the necessary rigidity to provide a high payload to self-weight ratio suitable for many applications in manufacturing, flight simulation systems, and medical robotics. Because of its closed structure, the kinematic control of such a mechanism is difficult. The inverse kinematics problem for such manipulators has a mathematical solution; however, the forward kinematics problem (FKP) is mathematically intractable. This work addresses the FKP and proposes a neural-network-based hybrid strategy that solves the problem to a desired level of accuracy, and can achieve the solution in real time. Two neural-network (NN) concepts using a modified form of multilayered perceptrons with backpropagation learning were implemented. The better performing concept was then combined with a standard Newton-Raphson numerical technique to yield a hybrid solution strategy. Simulation studies were carried out on a flight simulation syystem to check the validity o the approach. Accuracy of close to 0.01 mm and 0.01/spl deg/ in the position and orientation parameters was achieved in less than two iterations and 0.02 s of execution time for the proposed strategy.
Continuously latchable shuttle using carbon nanotubes on sidewall surfaces

We demonstrated a novel usage of self-adjusted, vertically aligned carbon nanotube (CNT) arrays integrated on the sidewalls of microstructures as latching components. The CNT array-based latching mechanism showed stable latching at multiple latching positions, together with reversible and bidirectional latching capabilities. The latchable shuttle using CNT latch could be adopted for diverse microelectromechanical systems (MEMS) that need precise positioning of movable structures without the necessity of continuous power consumptions to hold the displaced position.