gebhart/patrepeval huggingface dataset:
Efficient and transparent haptic rendering of rigid body motion with constraints (2009)

This work presents general purpose simulation and control techniques for efficient and transparent haptic rendering of rigid body motion with constraints. Transparent interaction is achieved by enabling users to feel collisions and to manipulate both virtual objects and virtual linkages. Efficient rendering is accomplished through fast approximations of rigid body interaction implemented in a local model with haptic performance. Hapic rendering of impacts is based on a new representation of rigid body contact. In this representation, contacts are infinitely stiff when they arise and have limited stiffness thereafter. Multiple impacts are resolved simultaneously, in a manner consistent with conservation of energy principles and with the force capabilities of the haptic device. Haptic rendering of impacts is beneficial in training simulators for dental procedures and bone surgeries, as well as CAD and virtual prototyping systems with force feedback. Realistic linkage manipulation is enabled by permitting users to operate linkages from any link and through singularities while restricting their motion according to the virtual environment geometry and the linkage topology. Linkage topology is imposed on users through penalizing users' departure from the configuration manifold of the virtual linkage. Operation of links with insufficient degrees of freedom is important in applications like training for laparoscopy, where the scope limits the tool motion at the entry point. Efficient rendering of rigid body motion with constraints is enabled by interfacing the device to a simulation through a local model of interaction. The model comprises constraints imposed on the virtual tool by virtual objects within an e-active neighborhood of the virtual tool and a dynamic proxy of the virtual tool. This model is the first that can be used to constrain both the translation and the rotation of the device and to add realistic forces to virtual environments generated using any commercial simulation package with interactive performance. The model is beneficial in consumer-grade haptic applications, because it allows easy development of haptic applications by users without detailed haptic knowledge. It can also be used to enable cooperative haptic manipulations in applications that involve two-handed operations and/or multiple users.
Mild and efficient ring opening of monoterpene-fused β-lactam enantiomers. Synthesis of novel β-amino acid derivatives (2004)

Both enantiomers of the N-Boc-activated monoterpene-fused -lactam 3 were readily convertible to N-Boc -amino acid 4, -amino ester 7, and carboxamide derivatives 9-11 via nucleophilic attack on the activated lactam bond. The corresponding -amino ester 7 was transformed to a novel amino acid 8.
Thymidine Phosphorylase Activity Associated with Platelet-Derived Endothelial Cell Growth Factor1 (1993)

Partial complementary DNA (cDNA) for thymidine phosphorylase (dThdPase) was cloned by means of a polymerase chain reaction. There was complete sequence identity between the amino acid sequence deduced from the nucleotide sequence of a clone (288 nucleotides) and the residues of platelet-derived endothelial cell growth factor (PD-ECGF). The amino acid sequence of all four peptide fragments from purified human dThdPase could be aligned with that of PD-ECGF. Our data indicate that residues 125-244 of PD-ECGF are identical to the sequence of human dThdPase. The molecular weights of human dThdPase and recombinant PD-ECGF (rPD-ECGF) that lacks 10 amino acids at the amino terminal were 55 and 52 kDa, respectively. Anti-PD-ECGF antibody recognized dThdPase, and anti-dThdPase antibody recognized rPD-ECGF. rPD-ECGF had dThdPase activity and its specific activity was similar to that of purified human dThdPase. dThdPase activity and molecules were detected in COS cells transfected with human PD-ECGF cDNA, but not in nontransfected cells. The sizes of PD-ECGF and dThdPase in the transfected COS cells were identical. These data suggest that human dThdPase is identical to PD-ECGF.
Regulation of Apoptosis during Neuronal Differentiation by Ceramide and b-Series Complex Gangliosides (2001)

Lipid analysis of gestational day E14.5 mouse brain revealed elevation of ceramide to a tissue concentration that induced apoptosis when added to the medium of neuroprogenitor cells grown in cell culture. Elevation of ceramide was coincident with the first appearance of b-series complex gangliosides (BCGs). Expression of BCGs by stable transfection of murine neuroblastoma (F-11) cells with sialyltransferase-II (ST2) resulted in a 70% reduction of ceramide-induced apoptosis. This was most likely due to an 80% reduced expression of prostate apoptosis response-4 (PAR-4). PAR-4 expression and apoptosis were restored by preincubation of ST2-transfected cells with N-butyl deoxinojirimycin (NB-DNJ) or PD98059, two inhibitors of ganglioside biosynthesis or p42/44 mitogen-activated protein (MAPK) kinase, respectively. In sections of day E14.5 mouse brain, the intermediate zone showed intensive staining for complex gangliosides, but only low staining for apoptosis (TUNEL) and PAR-4. Apoptosis and PAR-4 expression, however, were elevated in the ventricular zone which only weakly stained for complex gangliosides. Whole cell patch clamping revealed a 2-fold increased calcium influx in ST2-transfected cells, the blocking of which with nifedipine restored apoptosis to the level of untransfected cells. In serum-free culture, supplementation of the medium with IGF-1 was required to maintain MAPK phosphorylation and the anti-apoptotic effect of BCG expression. BCG-enhanced calcium influx and the presence of insulin-like growth factor-1 may thus activate a cell survival mechanism that selectively protects developing neurons against ceramide-induced apoptosis by up-regulation of MAPK and reduction of PAR-4 expression.
Reproducibility of Computer-Quantified Carotid Plaque Echogenicity (2000)

Our method decreases the variability between storage media and between probes but not the variability between degrees of magnification. It separates echomorphologically the carotid plaques associated with silent nonlacunar CT-demonstrated brain infarcts from plaques that are not so associated.
Kinetics of Death of Bacterial Spores at Elevated Temperatures (1964)

The kinetics of death of Bacillus stearothermophilus spores (FS 7954) suspended in phosphate buffer (pH 7) were studied over a temperature range of 127.2 to 143.8 C and exposure times of 0.203 to 4.150 sec. These short exposure were achieved by use of a tubular flow reactor in which a suspension of spores was injected into a hot flowing stream at the entrance of the reactor. Thermal equilibria of the suspension with the hot stream was achieved within 0.0006 sec. After flow through a fixed length of reactor, the stream containing the spores was cooled by flash vaporization and then assayed for viable count. The death rate data were fitted by a logarithmic expression. However, logarithmic death rate was only approximated in the tail or high-kill regions of exposure. Death rate constants obtained from this portion of the data were found to correlate by Arrhenius as well as Absolute Reaction Rate Theory relationships. Thermal-death time curves were found to correlate the data rather poorly. The activation energy and frequency constant for an Arrhenius relationship fit of the data were found to be 83.6 kcal/gmole and 10(47.2) min(-1), respectively. The standard enthalpy and entropy changes for an Absolute Reaction Rate Theory relationship fit of the data were found to be 84.4 kcal/gmole and 157 cal/gmole-K, respectively.
Theory analysis of wavelength dependence of laser-induced phase explosion of silicon (2008)

Wavelength dependence of laser ablation of silicon was investigated with nanosecond ultraviolet, visible, and infrared laser pulses in the irradiance range from 3×1010 to 1×1012 W/cm2. For 266 and 532 nm laser pulses, the depth of laser-produced crater shows a dramatic increase at a laser irradiance threshold of approximately 2×1010 and 4×1011 W/cm2 respectively, above which, large micron-sized particulates were observed to eject from the target about 300–400 ns after the laser pulse. In contrast, for 1064 nm pulse, this dramatic increase was not observed. The underlying mechanism for the observed threshold phenomenon is presented in this study, which can be attributed to the thermal diffusion and subsequent explosive boiling after the completion of the interaction between the nanosecond laser pulse and silicon. Based on our delayed phase explosive model, the ablation depths were calculated for different wavelengths and compared to experimental results. Plasma shielding during laser irradiation was included in the model, which plays a key role to the coupling of laser energy to the irradiated material.
Quantum Effects Strongly Influence the Surface Premelting of Ice (2007)

Clear evidence is presented that quantum effects in the motion of the H2O molecules strongly influence the surface premelting of ice. To reveal this behavior, structural and dynamical properties of the ice surface below the melting point were calculated using quantum molecular dynamics with an ab initio based force field. The quantum calculations predict the existence of a quasi-liquid-phase that extends for approximately 10 Å into the bulk, in agreement with the values obtained by optical ellipsometry experiments. Importantly, surface disorder in the topmost layers of the quantum ice persists at temperatures that are about 10−20 °C lower than its classical counterpart, indicating that the surface premelting of ice may largely be a result of quantum effects over a wide range of temperatures.
Robust, Simple Page Segmentation Using Hybrid Convolutional MDLSTM Networks (2017)

Analyzing and segmenting scanned documents is an important step in optical character recognition. The problem is difficult because of the complexity of 2D layouts, the small tolerance of segmentation errors in the output, and the relatively small amount of labeled training data available. Traditional approaches have relied on a combination of sophisticated geometric algorithms, domain knowledge, heuristics, and carefully tuned parameters. This paper describes the use of deep neural networks, in particular a combination of convolutional and multidimensional LSTM networks, for document image and demonstrates that relatively simple networks are capable of fast, reliable text line segmentation and document layout analysis even on complex and noisy inputs, without manual parameter tuning or heuristics. The method is easily adaptable to new datasets by retraining and an open source implementation is available.
The coenzyme specificity of <i>Candida tenuis</i> xylose reductase (AKR2B5) explored by site-directed mutagenesis and X-ray crystallography (2004)

CtXR (xylose reductase from the yeast Candida tenuis; AKR2B5) can utilize NADPH or NADH as co-substrate for the reduction of D-xylose into xylitol, NADPH being preferred approx. 33-fold. X-ray structures of CtXR bound to NADP+ and NAD+ have revealed two different protein conformations capable of accommodating the presence or absence of the coenzyme 2'-phosphate group. Here we have used site-directed mutagenesis to replace interactions specific to the enzyme-NADP+ complex with the aim of engineering the co-substrate-dependent conformational switch towards improved NADH selectivity. Purified single-site mutants K274R (Lys274-->Arg), K274M, K274G, S275A, N276D, R280H and the double mutant K274R-N276D were characterized by steady-state kinetic analysis of enzymic D-xylose reductions with NADH and NADPH at 25 degrees C (pH 7.0). The results reveal between 2- and 193-fold increases in NADH versus NADPH selectivity in the mutants, compared with the wild-type, with only modest alterations of the original NADH-linked xylose specificity and catalytic-centre activity. Catalytic reaction profile analysis demonstrated that all mutations produced parallel effects of similar magnitude on ground-state binding of coenzyme and transition state stabilization. The crystal structure of the double mutant showing the best improvement of coenzyme selectivity versus wild-type and exhibiting a 5-fold preference for NADH over NADPH was determined in a binary complex with NAD+ at 2.2 A resolution.
Photovoltage of rods and cones in the macaque retina (1995)

The kinetics, gain, and reliability of light responses of rod and cone photoreceptors are important determinants of overall visual sensitivity. In voltage recordings from photoreceptors in an intact primate retina, rods were found to be functionally isolated from each other, unlike the tightly coupled rods of cold-blooded vertebrates. Cones were observed to receive excitatory input from rods, which indicates that the cone pathway also processes rod signals. This input might be expected to degrade the spatial resolution of mesopic vision.
Mining checkins from location-sharing services for client-independent IP geolocation (2014)

Accurately determining the geographic location of an Internet host is important for location-aware applications such as location-based advertising and network diagnostics. Despite their fast response time, widely used database-driven geolocation approaches provide only inaccurate locations. Delay measurement based approaches improve the estimation accuracy but still suffer from a limited precision (about 10 km) and a long response time (tens of seconds) to localize a single PC, which cannot meet the demand of precise and real-time geolocation for location-aware applications. In this paper, we propose a new geolocation approach, Checkin-Geo, which exploits geolocation resources fundamentally different from existing database-driven (using DNS, Whois, etc.) or network delay measurement based approaches. In particular, we leverage the location data that users are willing to share in location-sharing services and logs of user logins from PCs for real-time and accurate geolocation. Experimental results show that compared to existing geolocation techniques, Checkin-Geo achieves 1) a median estimation error of 799 meters (an order of magnitude smaller than existing approaches), and 2) a negligible response time, which are promising for accurate location-aware applications.
Label switching over IEEE802.15.4e networks (2013)

ABSTRACT An open issue still to be addressed in low‐power lossy networks (LLNs) is how the application requirements, the available transport services, the network layer routes, and the data link‐layer resources are mapped efficiently. This can be explained by the fact that, in most LLNs, link‐layer resources cannot be easily managed; this results in a best effort IP layer, and traffic engineering performed solely through flow control at the transport layer. The new IEEE802.15.4e standard defines a link‐layer mechanism by which motes in the network synchronise and communicate by following a schedule. Each slot in that schedule can be seen as an atomic link‐layer resource, which can be allocated to any arbitrary link in the network. The schedule can be built to match the bandwidth, latency and power requirements of each mote in the network. Managing that schedule is performed centrally in IEEE802.15.4e networks today. This paper explores a solution to achieve the same goal in a distributed manner. Specifically, we argue that this problem is very similar to traffic engineering on today's Internet. We show how multiprotocol label switching can be mapped to LLNs to manage the network's schedule. By using the completely fair distributed scheduler, we show by simulation how this novel link‐layer resource allocation scheme yields a proper distribution of end‐to‐end delays among the motes and an average throughput that achieves the 70% of the maximum possible throughput in the worst conditions tested. Copyright © 2013 John Wiley & Sons, Ltd.
Cone beam SPECT reconstruction with camera tilt (1989)

The authors modified the cone beam filtered backprojection algorithm of L.A. Feldkamp et al. (1984) and applied it to the symmetric tilt-angle case. Both the modifications of the algorithm and a single preliminary test are reported.
Effects of Lime on the Chemistry of Sugarbeet Tissue (1981)

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On the Impact of Replica Placement to the Reliability of Distributed Brick Storage Systems (2005)

Data reliability of distributed brick storage systems critically depends on the replica placement policy, and the two governing forces are repair speed and sensitivity to multiple concurrent failures. In this paper, we provide an analytical framework to reason and quantify the impact of replica placement policy to system reliability. The novelty of the framework is its consideration of the bounded network bandwidth for data maintenance. We apply the framework to two popular schemes, namely sequential placement and random placement, and show that both have drawbacks that significantly degrade data reliability. We then propose the stripe placement scheme and find the near-optimal configuration parameter such that it provides much better reliability. We further discuss the possibility of addressing the problem of correlated brick failures in our analytical framework.
Microtubules and actin filaments are not critically involved in the biogenesis of epithelial cell surface polarity. (1986)

We have studied the role of microtubules and actin filaments in the biogenesis of epithelial cell surface polarity, using influenza hemagglutinin and vesicular stomatitis G protein as model apical and basolateral proteins in infected Madin-Darby canine kidney cells. Addition of colchicine or nocodazole to confluent monolayers at concentrations sufficient to completely disassemble microtubules did not affect the asymmetric budding of influenza or vesicular stomatitis virus and only slightly reduced the typical asymmetric surface distribution of their envelope proteins, despite extensive cytoplasmic redistribution of the Golgi apparatus. Alteration of microtubular function by taxol or dissociation of actin filaments by cytochalasin D also failed to have a significant effect. Furthermore, neither colchicine nor cytochalasin D pretreatment blocked the ability of subconfluent Madin-Darby canine kidney cells to sustain polarized budding of influenza virus a few hours after attachment to the substrate. Our results indicate that domain-specific microtubule or actin filament "tracks" are not responsible for the vectorial delivery of apically or basolaterally directed transport vesicles. In conjunction with currently available evidence, they are compatible with a model in which receptors in the cytoplasmic aspect of apical or basolateral regions provide vectoriality to the transport of vesicles carrying plasma membrane proteins to their final surface localization.
Use of Berberine in Treatment of Giardiasis (1975)

In early 1971,I was impressed by a chance observation suggesting that berberine—an alkaloid from the Indian medicinal plant<i>Berberis aristata</i>—may be an effective antigiardial drug.<sup>1</sup>To test this hypothesis, a clinical trial in pediatric patients was started at the Postgraduate Institute of Medical Education and Research, Chandigarh, India, where we had already been engaged in investigating various aspects of giardiasis. The study was later continued at the H. P. Medical College, Simla. Salient features of the group-comparative trial are summarized in the Table. Patients ranged in age from 5 months to 14 years, with a mean age of 5 years. Approximately 10% of patients in each of the subgroups did not complete the study. The data suggest that berberine, administered orally in a dose of 10 mg/kg/day for ten days, resulted in satisfactory parasitological cure, comparable to that obtained with other established antigiardial drugs (quinacrine hydrochloride, furazolidone, and metronidazole). It
Mycophenolate mofetil for systemic lupus erythematosus refractory to other immunosuppressive agents (2002)

MMF appears to be a safe and effective alternative immunosuppressant for extra-renal and renal disease in SLE not responding to conventional immunosuppressive treatment.
The relative amounts of plasma transthyretin forms in familial transthyretin amyloidosis: A quantitative analysis by Fourier transform ion-cyclotron resonance mass spectrometry (2011)

Familial transthyretin amyloidosis (ATTR) is a fatal autosomal dominant disease characterized by the formation of amyloid fibers, mainly composed of transthyretin (TTR). Protein aggregation and amyloid fiber formation are considered concentration dependent processes and since most ATTR patients are heterozygous it is crucial to determine the ratio between mutant and non-mutant TTR forms in human plasma. Using a high resolution mass spectrometry based approach we determined the ratio of TTR forms in ATTR patients, V30M mutation carriers, symptomatic and asymptomatic ones, as well as ATTR patients that received a wild type cadaveric liver transplant. Domino transplanted patients that received a liver from an ATTR patient were also investigated. We found that although wild type TTR is diminished in the plasma of non-transplanted ATTR patients comparatively to healthy subjects, the relationship with the V30M variant does not change with illness progression. Those who received a wild type liver showed no mutant protein while domino transplanted patients presented the same relative amount of V30M as found in asymptomatic and symptomatic individuals. The V30M to wild type TTR ratio in plasma is the same for all ATTR patients studied, showing no variation with disease clinical progression. Our results point to the involvement of additional non-genetic factors on the pathogenesis of this disease.
Di‐ und Tetracyanpyrazine (1975)

Abstract Diaminomaleonitril ( 2 ) wird mit Di‐ bzw. Tetraketonen und Ketoaldehyden 1 zu Di‐ bzw. Tetracyanpyrazinen 3 umgesetzt. Anstelle einiger Dicarbonylverbindungen werden auch α‐(Hydroxyimino)ketone 4 verwendet. Durch Reaktion von Diiminosuccinonitril ( 6 ) mit Di‐ bzw. Tetraaminen 5 werden Di‐ bzw. Tetracyanpyrazine 8 erhalten. Die Umsetzung einiger Dicyanpyrazine mit Ammoniak führt zu Aminoimino‐5 H ‐pyrrolo[3,4‐ b ]pyrazinen 9 . Die IR‐ und Elektronenspektren werden diskutiert.
Automated Spatial Calibration of HMD Systems with Unconstrained Eye-cameras (2016)

Properly calibrating an optical see-through head-mounted display (OST-HMD) and maintaining a consistent calibration over time can be a very challenging task. Automated methods need an accurate model of both the OST-HMD screen and the user's constantly changing eye-position to correctly project virtual information. While some automated methods exist, they often have restrictions, including fixed eye-cameras that cannot be adjusted for different users.To address this problem, we have developed a method that automatically determines the position of an adjustable eye-tracking camera and its unconstrained position relative to the display. Unlike methods that require a fixed pose between the HMD and eye camera, our framework allows for automatic calibration even after adjustments of the camera to a particular individual's eye and even after the HMD moves on the user's face. Using two sets of IR-LEDs rigidly attached to the camera and OST-HMD frame, we can calculate the correct projection for different eye positions in real time and changes in HMD position within several frames. To verify the accuracy of our method, we conducted two experiments with a commercial HMD by calibrating a number of different eye and camera positions. Ground truth was measured through markers on both the camera and HMD screens, and we achieve a viewing accuracy of 1.66 degrees for the eyes of 5 different experiment participants.