gebhart/patrepeval huggingface dataset:
Semi-automatic intracranial tumor segmentation and tumor tissue classification based on multiple MR protocols (2012)

Segmentation of intracranial tumors in Magnetic Resonance (MR) data sets and classification of the tumor tissue into vital, necrotic, and perifocal edematous areas is required in a variety of clinical applications. Manual delineation of the tumor tissue boundaries is a tedious and error-prone task, and reproducibility is problematic. Furthermore, tissue classification mostly requires information of several MR protocols and contrasts. Here we present a nearly automatic segmentation and classification algorithm for intracranial tumor tissue working on a combination of T1 weighted contrast enhanced (T1CE) and fluid attenuated inversion recovery (FLAIR) data sets. Both data types are included in MR intracranial tumor protocols that are used in clinical routine. The algorithm is based on a region growing technique. The main required user interaction is a mouse click to provide the starting point. The region growing thresholds are automatically adapted to the requirements of the actual data sets. If the segmentation result is not fully satisfying, the user is allowed to adapt the algorithmic parameters for final fine-tuning. We developed a user interface, where the data sets can be loaded, the segmentation can be started by a mouse click, the parameters can be amended, and the segmentation results can be saved. With this user interface, our segmentation tool can be used in the hospital on an image processing workstation or even directly on the MR scanner. This enables an extensive validation study. On the 20 clinical test cases of human intracranial tumors we investigated so far, the results were satisfying in 85% of the cases.
Organotemplate-Free and Fast Route for Synthesizing Beta Zeolite (2008)

Beta Zeolite has been widely used in industry, and its synthesis usually takes several days in the presence of organic templates. We demonstrate here an organotemplate-free and fast route for synthesizing Beta zeolite by addition of Beta seeds in the starting gel in the absence of any organic templates.
A bootstrap voltage reference based upon an N-type negative resistance device (1993)

A circuit that develops a reference voltage based upon the stability of the current of an N-type negative-resistance device (NNRD) in the neighborhood of the current peak is described. The NNRD is self-driven in a bootstrap configuration utilizing a single operational amplifier, with the bias circuit acting as a stiff voltage source having a negative Thevenin equivalent DC resistance. The analysis is specialized to the case of a particular NNRD, a p-n junction tunnel diode (TD), and a series of matching networks coupling the TD to the remainder of the bootstrap circuit are analyzed to demonstrate that a properly matched TD, biased by this bootstrap circuit, can be made stable against oscillation. The regulation of bias fluctuations, noise performance, temperature stability, and immunity to neutron damage are reviewed. Comparison is made to avalanche-diode-based bootstrap references. NNRD-based voltage references may have an impact in circuits and material systems where fabrication of high-quality Zener devices is not possible.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Supported Ru olefin metathesis catalysts <i>via</i> a thiolate tether (2019)

Thiolate-coordinated ruthenium alkylidene complexes can give high Z-selectivity and stereoretentivity in olefin metathesis. To investigate their applicability as heterogeneous catalysts, we have successfully developed a methodology to easily immobilize prototype ruthenium alkylidenes onto hybrid mesostructured silica via a thiolate tether. In contrast, the preparation of the corresponding molecular complexes appeared very challenging in solution. These prototype supported complexes contain small thiolates but still, they are slightly more Z-selective than their molecular analogues. These results open the door to more active and selective heterogeneous catalysts by supporting more advanced thiolate Ru-complexes.
Reconfigurable manufacturing systems and their enabling technologies (2000)

A reconfigurable manufacturing system (RMS) is designed for rapid adjustment of production capacity and functionality in response to new market conditions and new process technology. It has several distinct characteristics including modularity, integrability, customisation, convertibility and diagnosability. There are a number of key interrelated technologies that should be developed and implemented to achieve these characteristics. This paper examines and identifies these technologies. After a brief description of the RMSs and their goals, aspects of reconfiguration (reconfigurable system, software, controller, machine, and process) are explained; this provides one with a better understanding of the enabling technologies of RMSs. Some of the issues related to the technology requirements of RMSs at the system and machine design levels, and ramp -up time reduction are then explained. The paper concludes with descriptions of some of the future research directions for RMSs.
Melatonin inhibits cholangiocyte hyperplasia in cholestatic rats by interaction with MT1 but not MT2 melatonin receptors (2011)

In bile duct-ligated (BDL) rats, large cholangiocytes proliferate by activation of cAMP-dependent signaling. Melatonin, which is secreted from pineal gland as well as extrapineal tissues, regulates cell mitosis by interacting with melatonin receptors (MT1 and MT2) modulating cAMP and clock genes. In the liver, melatonin suppresses oxidative damage and ameliorates fibrosis. No information exists regarding the role of melatonin in the regulation of biliary hyperplasia. We evaluated the mechanisms of action by which melatonin regulates the growth of cholangiocytes. In normal and BDL rats, we determined the hepatic distribution of MT1, MT2, and the clock genes, CLOCK, BMAL1, CRY1, and PER1. Normal and BDL (immediately after BDL) rats were treated in vivo with melatonin before evaluating 1) serum levels of melatonin, bilirubin, and transaminases; 2) intrahepatic bile duct mass (IBDM) in liver sections; and 3) the expression of MT1 and MT2, clock genes, and PKA phosphorylation. In vitro, large cholangiocytes were stimulated with melatonin in the absence/presence of luzindole (MT1/MT2 antagonist) and 4-phenyl-2-propionamidotetralin (MT2 antagonist) before evaluating cell proliferation, cAMP levels, and PKA phosphorylation. Cholangiocytes express MT1 and MT2, CLOCK, BMAL1, CRY1, and PER1 that were all upregulated following BDL. Administration of melatonin to BDL rats decreased IBDM, serum bilirubin and transaminases levels, the expression of all clock genes, cAMP levels, and PKA phosphorylation in cholangiocytes. In vitro, melatonin decreased the proliferation, cAMP levels, and PKA phosphorylation, decreases that were blocked by luzindole. Melatonin may be important in the management of biliary hyperplasia in human cholangiopathies.
Dramatic enhancement of intrinsic two-photon absorption in a conjugated porphyrin dimerElectronic supplementary information (ESI) available: Experimental procedures. See http://www.rsc.org/suppdata/cp/b3/b313399k/ (2003)

We report strong cooperative enhancement of simultaneous two-photon absorption cross section in a porphyrin dimer. The two-photon cross section, σ2 = 6 × 10−47 cm4s/photon, corresponds to a 400-fold increase over the value measured for the monomer, and is one of the largest ever obtained for organic chromophore of similar size.
Multimode variable bit rate speech coding: an efficient paradigm for high-quality low-rate representation of speech signal (1999)

The speech signal consists of a time-varying ensemble of different types of segments with distinct characteristics, which require different degrees of coding resolution in order to retain an overall high voice quality. A fixed-rate coder can capture such time-varying characteristics only if it operates at a high enough bit rate. At a low bit rate, a fixed-rate coder will not be able to capture all of these various segments well and will fail to render high voice quality. A multimode variable bit rate (VBR) coder uses an arsenal of modes, operating at different bit rates. These modes are designed to represent these different speech segments optimally with the right amount of coding resolution. Thus, a multimode VBR codec adapts the coding mechanism to the input speech and delivers high quality at low (average) rates. This paper presents the essential framework and the unique advantages of a multimode VBR codec and suggests algorithms for the different modes.
DOIS: a diffractive optic image spectrometer (1996)

This paper will detail the basic characteristics and performance of a diffractive optic imaging spectrometer (DOIS). Diffractive optical element technology combined with a conventional CCD camera produces an elegant configuration for adding spectroscopy capabilities to current imaging systems. Its resolution rivals that of competing technologies, capable of hyperspectral resolution when used along with basic image processing techniques. DOIS is a rugged, economical, programmable, practical image spectrometer that can be adapted for use in visible, infra- red, and ultraviolet spectra for a multitude of applications.
Neural stem cells as delivery vehicles (2003)

The discovery of neural stem cells (NSCs) has changed our long-held view that the adult mammalian central nervous system (CNS) is postmitotic and lacks the capability for self-repair. The role of NSCs in physiological and pathological processes in the brain is slowly emerging. We are now able to isolate, expand, genetically engineer and transplant NSCs. An important characteristic of NSCs, not fully understood so far, is their migratory ability and their tropism to brain pathology. The migratory ability of NSCs and their capacity to differentiate into all neural phenotypes gives us a potentially powerful tool for the treatment of both diffuse and localised neurologic disorders. The delivery of gene products by NSCs to specific sites in the CNS can maximise the efficiency of delivery and minimise the unwanted exposure of surrounding intact tissue. Here, the recent preclinical advances in the use of NSCs for the delivery of therapeutic products are reviewed, in particular the employment of their migratory potential and the homing ability to pathology in the nervous system.
Detection of specific types of human papillomavirus in cervical scrapes, anal scrapes, and anogenital biopsies by DNA hybridization (1987)

Specific varieties of human papillomavirus (HPV) infecting the anogenital region were detected in clinical samples by use of a filter hybridization technique suitable for rapid screening of cervical and anal scrapes. In this way possibly benign types (HPV6 and HPV11) could be differentiated from types thought to be capable of malignant transformation (HPV 16 and HPV 18). Cervical or anal canal cells were applied directly to nylon filters and fixed by u.v. irradiation before hybridization with mixed viral DNA probes under both low- and high-stringency conditions. In addition, probe for the human Alu-repeated DNA sequence was used to assess the relative amount of total nucleic acids in each sample applied to the filter. HPV DNA was detected in 3 of 19 cervical scrapes from patients with no past or present history of wart virus infection or cervical dysplasia. Within a positive study group totalling 71 patients, HPV (6/11 or 16/18) was detected in cervical scrapes from 24% of 41 patients who did not have visible genital dysplasia, 30% of 27 patients with visible genital dysplasia or cervical intraepithelial neoplasia (CIN) I, and in 1 of 3 patients with past CIN II/III. In addition, HPV6/11 or 16/18 DNA was detected in anal scrapes from 3 of 6 male patients and in 85% of genital biopsies. A notably high proportion (4/6) of vaginal condylomata were positive with both the HPV6/11 and the HPV16/18 mixed viral DNA probes. Of the biopsies prepared for histopathology and positive for HPV DNA, the HPV group-specific antigen could be detected in only 60%.
Diopside (CaO·MgO·2SiO2)–fluorapatite (9CaO·3P2O5·CaF2) glass-ceramics: potential materials for bone tissue engineering (2011)

Glass-ceramics in the diopside (CaMgSi2O6)–fluorapatite [Ca5(PO4)3F] system are potential candidates for restorative dental and bone implant materials. In the present study, a series of glasses along the diopside–fluorapatite binary system have been prepared with varying diopside/fluorapatite ratios for their potential applications in bone tissue engineering. The glasses were obtained from compositions with fluorapatite contents varying between 0 and 40 wt%. The sintering ability and crystallization kinetics of as obtained amorphous glasses have been studied through hot-stage microscopy (HSM) and differential thermal analysis (DTA), respectively, while crystalline phase evolution in sintered GCs has been followed by X-ray diffraction (XRD) adjoined with the Rietveld-R.I.R. technique and scanning electron microscopy (SEM). Further, biodegradation and apatite forming ability of glass-ceramics were investigated by immersion of glass-ceramic discs in simulated body fluid (SBF) solution while chemical degradation and weight loss of glass-ceramics were studied by immersion in Tris–HCl in accordance with the ISO 10993-14 standard. The addition of fluorapatite (10–25 wt%) in the diopside glass system significantly enhanced the sintering ability of glass-ceramics and improved their apatite forming ability along with their biodegradation behaviour. Moreover, the in vitro cellular responses to glass-ceramics showed good cell viability and significant stimulation of osteoblastic differentiation, suggesting the possible use of the glass-ceramics for bone regeneration.
Flow Field Characteristics of Oblique Shocks Generated Using Microjet Arrays (2014)

High momentum microjet arrays are used to generate single and/or multiple oblique shocks in a supersonic crossflow. The properties of these microjet generated shocks can be tailored to be parallel or coalescing, at variable supply pressures, depending on the application. Flowfield measurements using Particle Image Velocimetry were obtained for a range of test conditions. The velocity field obtained clearly shows the global effect of the microjet generated oblique shocks on the flowfield. The jump in the velocity field across the oblique shock and the extent of the influence of the shock and expansion fan are also clearly seen from the results. The microjet generated shocks were compared with a ramp shock and it was found that the properties of the two share some similarity. The strength of the microjet shocks was found to be constant along the length of the shock. The results obtained were compared to previous results obtained using Background Oriented Schlieren and shadowgraph techniques and were found to be consistent. The parallel and coalescing properties of the multiple microjet shocks were also investigated.
Beam purification by photodetachment (invited) (2012)

Ion beam purity is of crucial importance to many basic and applied studies in nuclear science. Selective photodetachment has been proposed to suppress unwanted species in negative ion beams while preserving the intensity of the species of interest. A highly efficient technique based on photodetachment in a gas-filled radio frequency quadrupole ion cooler has been demonstrated. In off-line experiments with stable ions, up to 10(4) times suppression of the isobar contaminants in a number of interesting radioactive negative ion beams has been demonstrated. For selected species, this technique promises new experimental possibilities in studies on exotic nuclei, accelerator mass spectrometry, and fundamental properties of negative atomic and molecular ions.
‘CMPO-substituted’ calix[4]arenes, extractants with selectivity among trivalent lanthanides and between trivalent actinides and lanthanides (1998)

Calix[4]arenes substituted by acetamidophosphine oxide groups at their wider (upper) rim not only exhibit excellent extraction efficiency towards trivalent cations but also show pronounced selectivity for the light lanthanides and actinides in their extraction from highly saline or acidic media.
MIMO Communication System with Reconfigurable Circular Patch Antennas (2008)

Recent advances in Multiple Input Multiple Output (MIMO) systems have shown that multi element reconfigurable antennas can improve the throughput and the robustness of the wireless communication link [1]. Efficient use of these antennas in MIMO systems has been shown to be a challenging task, still unexplored [2]. The
The Radiocontrast Molecule in Anaphylaxis: A Surprising Antigen (2004)

X-ray contrast media are individually injected into human blood vessels in greater quantities than any other pharmacological substance. Adverse reactions to these substances have heretofore been considered anaphylactoid in nature. Others and we have demonstrated that the mechanisms involved are multifactorial and may involve activation of mast cells and basophils, activation of the complement system, activation of the contact system, and the conversion of L-arginine into nitric oxide. Appropriate pretreatment with corticosteriods will diminish the incidence of reactions. Most recently we have demonstrated that the contrast media function as 'pseudoantigens' (PsA). They can combine with antibodies, but cannot themselves produce antibodies. This property appears to be dependent on aggregation in high concentrations and varies with the individual media. It furthermore appears to be non-specific in relation to antibodies, and suggests that binding occurs to the Fc portion of immunoglobulins. We have now demonstrated that the least toxic of current media demonstrate the best antibody binding and in sufficient concentration can inhibit contrast induced mast cell activation and/or non-contrast antigen induced mast cell activation, apparently due to in vivo pseudoantigen excess. In lesser concentrations and/or lesser binding, the media can trigger mast cell activation.
The role of constitutive nonlinearities and sound modulation in the generation of the acoustic radiation force (2011)

This study investigates the acoustic radiation force (ARF) in soft tissues when the generating ultrasound field is modulated with a low-frequency envelope (102-104 Hz range). On approximating the soft tissue as that of a nonlinear elastic material with heat conduction and viscosity, the system of nonlinear balance equations, governing both the ultrasound-scale oscillatory motion and the ARF-induced mean motion, is formulated explicitly. To deal with the effects of ultrasound modulation, a dual-time-scale approach featuring the “fast” (ultrasound-scale) and “slow” (modulation-scale) temporal coordinates is deployed. In this setting the governing equations for the mean motion, featuring the ARF as the body force term, are extracted by taking the “fast” time average of the nonlinear balance laws. The ARF is shown to consist of two distinct terms, namely (i) the potential term, which is proportional to the gradient of the ultrasound intensity and (ii) the axial term, which contains both an attenuation-driven component and a modulation-driven component. A salient feature of the new solution for the ARF is that its entries feature specific combinations of the elastic nonlinearity coefficients, which may vary depending on tissue type. For completeness, the proposed formula is illustrated by numerical simulations and compared to the existing expressions.
Binarization method based on pixel-level dynamic thresholds for change detection in image sequences (2006)

A new change detection scheme with enhanced tolerance to noises and illumination changes is proposed in this paper. In addition to computing a global threshold for an entire target image, a dynamically adjusted cumulative histogram is computed to find the most suitable threshold for every pixel in the target image. A binarization method is designed to integrate the global threshold and the dynamic thresholds. The adoption of pixel-level dynamic thresholds makes the proposed method more robust. Experimental results show that the proposed scheme is able to locate motion pixels more accurately and work well under various kinds of illumination conditions.
Experimental demonstration of a polarization-insensitive self-homodyne detection receiver for optical access (2015)

We demonstrate a polarization and phase noise insensitive self-homodyne detection receiver combining coherent and direct detection receivers with a MISO equalizer. We show less than 0.6 dB penalty with laser linewidths up to 30 MHz regardless of the input polarization.
Cell reprogramming using extracellular vesicles from differentiating stem cells into white/beige adipocytes (2020)

Stem cell-derived extracellular vesicles (EVs) offer alternative approaches to stem cell-based therapy for regenerative medicine. In this study, stem cell EVs derived during differentiation are developed to use as cell-free therapeutic systems by inducing tissue-specific differentiation. EVs are isolated from human adipose-derived stem cells (HASCs) during white and beige adipogenic differentiation (D-EV and BD-EV, respectively) via tangential flow filtration. D-EV and BD-EV can successfully differentiate HASCs into white and beige adipocytes, respectively. D-EV are transplanted with collagen/methylcellulose hydrogels on the backs of BALB/c mice, and they produce numerous lipid droplets in injected sites. Treatments of BD-EV attenuate diet-induced obesity through browning of adipose tissue in mice. Furthermore, high-fat diet-induced hepatic steatosis and glucose tolerance are improved by BD-EV treatment. miRNAs are responsible for the observed effects of BD-EV. These results reveal that secreted EVs during stem cell differentiation into white adipocytes or beige adipocytes can promote cell reprogramming.
Retransmission schemes for streaming internet multimedia (2002)

This paper presents a trace-driven simulation study of two classes of retransmission timeout (RTO) estimators in the context of real-time streaming over the Internet. We explore the viability of employing retransmission timeouts in NACK-based (i.e., rate-based) streaming applications to support multiple retransmission attempts per lost packet. The first part of our simulation is based on trace data collected during a number of real-time streaming tests between dialup clients in all 50 states in the U.S. (including 653 major U.S. cities) and a backbone video server. The second part of the study is based on streaming tests over DSL and ISDN access links. First, we define a generic performance measure for assessing the accuracy of hypothetical RTO estimators based on the samples of the round-trip delay (RTT) recorded in the trace data. Second, using this performance measure, we evaluate the class of TCP-like estimators and find the optimal estimator given our performance measure. Third, we introduce a new class of estimators based on delay jitter and show that they significantly outperform TCP-like estimators in NACK-based applications with low-frequency RTT sampling. Finally, we show that high-frequency sampling of the RTT completely changes the situation and makes the class of TCP-like estimators as accurate as the class of delay-jitter estimators.