gebhart/patrepeval huggingface dataset:
Status of piezoelectric single crystal growth for medical transducer applications (2004)

Single crystal piezoelectrics such as PMN-PT are leading to dramatic improvements in transducer, sensor and actuator technology. The potential benefit of implementing these materials is clearly promising in terms of increased bandwidth, sensitivity and source levels due to ultrahigh electromechanical coupling factors (k/sub 33/>94%), high piezoelectric coefficients (d/sub 33/>2500pC/N), high strain levels (>0.6%), and low hysteresis. TRS is investigating a variety of uses for piezoelectric single crystals in medical transducer applications such as ultrasound harmonic imaging and high frequency transducers. Harmonic imaging requires very broad bandwidth ultrasonic transducers. By using single crystals, which inherently have more bandwidth, the complex engineering normally associated with achieving increased bandwidth will be reduced. Simple ultrasound transducers that have been constructed from crystals exhibiting bandwidths of 100% (if high impedance, backing layers are used, 140% can be achieved) and insertion losses less than similarly constructed PZT transducers with only a 70% bandwidth. To date, commercialization of these materials for ultrasound has been limited by low yields, small size, and high cost. The primary cost driver for single crystals is the amount of useable material yielded per growth run. Currently these crystals are grown by the Bridgman method, which involves moving a crucible containing a molten charge relative to a stationary temperature gradient resulting in unidirectional solidification. One limiting factor of the Bridgman growth technique for PMN-PT is that useful compositions of this system have a segregation coefficient less than 1, so there is a significant compositional gradient along the growth axis, which severely limits the amount of crystal yielded per growth run. The current state of the art is Bridgman-grown 1.5-2" diameter boules. Scaling up and the use of zone melting in the Bridgman technique to increase useable length are expected to yield price reductions for large volume production that are 2 to 3 times that of high quality PZT ceramic (/spl sim/$20 to 30/cc). The current status of the growth development including current issues as well as preliminary results of utilizing crystals in medical transducer applications will be discussed.
A Widely Deployed Solution to the Generic Routing Encapsulation (GRE) Fragmentation Problem (2015)

This memo describes how many vendors have solved the Generic Routing
Encapsulation (GRE) fragmentation problem. The solution described
herein is configurable. It is widely deployed on the Internet in its
default configuration.
A WDM CMOS Photonic Platform for Chip-to-Chip Optical Interconnects (2014)

Optical interconnects play a continually-increasing role in the interconnect hierarchy of high-speed digital systems. We present our vision for photonically-interconnected many-chip modules and progress toward an ultra-dense, low-power silicon photonic technology that supports this vision.
Fc Receptor-Like 3 Protein Expressed on IL-2 Nonresponsive Subset of Human Regulatory T Cells (2009)

Fc receptor-like 3 (FCRL3) is a cell surface protein homologous to Fc receptors. The FCRL3 gene is present in humans but not in mice. We found that FCRL3 protein is expressed on 40% of human naturally occurring CD4(+) regulatory T (nTreg) cells (CD4(+)CD25(+)CD127(low)). Sorted nTreg cells with the surface phenotype FCRL3(+) and FCRL3(-) were both hypoproliferative to TCR stimulation and both suppressive on proliferation of conventional T cells (CD4(+)CD25(-)) in vitro. They both expressed forkhead box p3 (Foxp3) protein, the intracellular regulatory T cell marker. However, in contrast to FCRL3(-) nTreg cells, FCRL3(+) nTreg cells were not stimulated to proliferate by the addition of exogenous IL-2. In addition, Foxp3(+) cells induced from conventional T cells by TGF-beta treatment did not exhibit FCRL3 expression. These results suggest that the FCRL3(+) subset of human nTreg cells identified in this study arise in vivo and Foxp3 expression alone is not sufficient to induce FCRL3 expression. FCRL3 may be involved in human-specific mechanisms to control the generation of nTreg cells.
Synthesis, evaluation and application of novel bifunctional N,N-di-isopropylbenzylamineboronic acid catalysts for direct amide formation between carboxylic acids and amines (2007)

Three new derivatives of N,N-di-isopropylbenzylamine-2-boronic acid have been prepared by directed metallation-borylation methods, to derive the 3-fluoro, 3-methoxy and 5-trifluoromethyl systems. The addition of an electron withdrawing group does increase the reactivity of such systems to act as improved direct amide formation catalysts under the most ambient conditions employed to date. In contrast, an electron donating group does result in considerable lowering of catalyst reactivity. DoE studies have been used to identify the ideal reaction conditions under which these types of catalysts should be used, typified by the parent system N,N-di-isopropylbenzylamine-2-boronic acid. This shows best performance at a 5 mol% loading and under higher dilution conditions, which most likely reflect the drying capacity of the solvent.
Endothelial cells support osteogenesis in an in vitro vascularized bone model developed by 3D bioprinting (2020)

Bone is a highly vascularized tissue, in which vascularization and mineralization are concurrent processes during skeletal development. Indeed, both components should be included in any reliable and adherent in vitro model platform for the study of bone physiology and pathogenesis of skeletal disorders. To this end, we developed an in vitro vascularized bone model, using a gelatin-nanohydroxyapatite (gel-nHA) three-dimensional (3D) bioprinted scaffold. First, we seeded human mesenchymal stem cells (hMSCs) on the scaffold, which underwent osteogenic differentiation for 2 weeks. Then, we included lentiviral-GFP transfected human umbilical vein endothelial cells (HUVECs) within the 3D bioprinted scaffold macropores to form a capillary-like network during 2 more weeks of culture. We tested three experimental conditions: condition 1, bone constructs with HUVECs cultured in 1:1 osteogenic medium (OM): endothelial medium (EM); condition 2, bone constructs without HUVECs cultured in 1:1 OM:EM; condition 3: bone construct with HUVECs cultured in 1:1 growth medium:EM. All samples resulted in engineered bone matrix. In conditions 1 and 3, HUVECs formed tubular structures within the bone constructs, with the assembly of a complex capillary-like network visible by fluorescence microscopy in the live tissue and histology. CD31 immunostaining confirmed significant vascular lumen formation. Quantitative real-time PCR was used to quantify osteogenic differentiation and endothelial response. Alkaline phosphatase and runt-related transcription factor 2 upregulation confirmed early osteogenic commitment of hMSCs. Even when OM was removed under condition 3, we observed clear osteogenesis, which was notably accompanied by upregulation of osteopontin, vascular endothelial growth factor, and collagen type I. These findings indicate that we have successfully realized a bone model with robust vascularization in just 4 weeks of culture and we highlighted how the inclusion of endothelial cells more realistically supports osteogenesis. The approach reported here resulted in a biologically inspired in vitro model of bone vascularization, simulating de novo morphogenesis of capillary vessels occurring during tissue development.
Motors Employing REBCO CORC and MgB2 Superconductors for AC Stator Windings (2021)

Future all-electric aircraft will employ highly efficient compact and lightweight machines for power generation and propulsion applications. Previous studies have indicated that the most attractive options include synchronous machines employing superconducting excitation and stator windings for achieving high power density and efficiency. The dc excitation winding could be constructed using a variety of superconductors, but the choice for ac stator windings is limited. High conductivity aluminum conductor at cryogenic temperature is a possible option but it is expected to be heavier than a superconducting winding and will require more extensive cooling as the losses within the winding pack will be much larger. A conductor-on-round-core (CORC) cable using REBCO tapes looks like an attractive option as it enables compound bending for constructing saddle coils. Here, we investigate using this cable for the stator winding of a 3 MW, 4500 RPM, 4-pole propulsion motor and compare with an identical motor employing an MgB <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> stator winding. The motor configuration assumes saddle-shaped coils for the stator winding. Each saddle coil constitutes a double pancake. A round conductor capable of bending in three-dimensional is preferred for such coils, making the round CORC cable ideal for this application. The cable employs striated REBCO with striation width as small as 1/3 mm. The ac field in the stator winding region is about 0.7 T at 150 Hz and the cable is operated at 50% of its critical current for limiting ac losses and for providing a safety margin. Individual tapes in the CORC cable experience field perpendicular to its broad face resulting in high ac losses. Comparing the performance of motors employing CORC and MgB <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> cables for the stator, we find that the ac losses in the CORC stator are much larger than the MgB <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> stator. High losses in the CORC stator winding make this option less attractive unless coolant power is freely available, such as in LH <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> -fueled planes. However, this machine with CORC coils is the most compact and lightweight option. Such compact light mass motors could be attractive for LH <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> fueled applications, such as interstate trucks, heavy machinery, locomotive hauling goods trains, ships (especially for podded propellers), etc.
Sol-Gel Chemistry Materials for Anti-Corrosion Coatings (2013)

This review paper summarizes the current state of the art of sol-gel technology for formulating anti corrosive protective coating. A brief description of the mechanism of sol-gel reactions, various parameters that influence the property of the final product and the course of the sol-gel reaction has been given. Different types of metal precursors that are extensively used in sol preparation and the advantages and disadvantages have also been mentioned in brief. Surface chemistry of sol-gel matrix and various stabilizing and destabilizing forces that are active on the surface of colloidal particles have also been discussed. Problems related to obtaining good quality product with uniformly distributed concentrations have been outlined. Possible pathways for further improvement of anti-corrosive properties of the coating have been described, such as incorporation of various types of additives into the sol matrix prior to coating. As a whole the present study summarizes the superiority and benefits of organic-inorganic hybrid coatings using sol-gel technique and having good protective and anti-corrosive properties.
Teager energy and the ambiguity function (1999)

The connection between the Teager energy operator and the ambiguity function is established in this correspondence after defining the Teager operator over complex-valued signals. This relation allows the use of the Teager energy in estimating the second moment angular bandwidth and the moments of a signal duration (spread) and that of its spectrum.
Excitation Wavelength Dependent Reversible Photoluminescence Peak in Iodide Perovskites (2018)

Halide perovskites have indisputably exceptional optical and electronic properties, which are attractive for next-generation optoelectronic device technologies. We report on a reversible photoluminescence (PL) peak in iodide-based organic-inorganic lead halide perovskite materials under a two-photon absorption (TPA) process, while tuning the excitation wavelength. This phenomenon occurs when the incoming femtosecond (fs) laser photon energy is higher than a threshold energy. Intriguingly, this phenomenon also occurs in other kinds of iodide perovskite materials. Moreover, two more shorter wavelength peaks exhibit and become prominent when the excitation photon energy is being tuned in the high energy wavelength spectrum, while laser power is remained constant. However, the spectral PL energy window between the original material peak and the first high energy peak can vary based on the optoelectronic properties of the prepared films. The same phenomenon of reversible PL peak is also observed in various iodide based organic-inorganic halides as well as all-inorganic perovskite single crystals and polycrystals. We attribute to the reversible PL peak to the photoinduced structural deformation and the associated change in optical bandgap of iodide perovskites under the femtosecond laser excitation. Our findings will introduce a new degree of freedom in future research as well as adding new functionalities to optoelectronic applications in these emerging perovskite materials.
Electrochemical Characteristics of LiCoO2 Single Particle at High Temperatures (2010)

Abstract not Available.
Purification, crystallization and preliminary X-ray diffraction analysis of the putative ABC transporter ATP-binding protein fromThermotoga maritima (2008)

Adenosine triphosphate (ATP) binding cassette transporters (ABC transporters) are ATP hydrolysis-dependent transmembrane transporters. Here, the overproduction, purification and crystallization of the putative ABC transporter ATP-binding protein TM0222 from Thermotoga maritima are reported. The protein was crystallized in the hexagonal space group P6(4)22, with unit-cell parameters a = b = 148.49, c = 106.96 A, gamma = 120.0 degrees . Assuming the presence of two molecules in the asymmetric unit, the calculated V(M) is 2.84 A(3) Da(-1), which corresponds to a solvent content of 56.6%. A three-wavelength MAD data set was collected to 2.3 A resolution from SeMet-substituted TM0222 crystals. Data sets were collected on the BL38B1 beamline at SPring-8, Japan.
EPR Study of the Low-Spin [d3; S =/2], Jahn−Teller-Active, Dinitrogen Complex of a Molybdenum Trisamidoamine (2007)

The first EPR study of the trisamidoamine complex, [Mo]N2, where [Mo] = Mo(III)[HIPTN3N] and HIPT = [3,5-(2,4,6-i-Pr3-C6H2)2C6H3NCH2CH2]3N3-, reveals that this low-spin (S = 1/2) [d3] complex exhibits a 2E state that undergoes a pseudo Jahn−Teller distortion in the adiabatic limit, modified by interactions with the solvent, and analysis gives approximate values of interaction energies. The experiments establish that [Mo]N2 exhibits the low-spin [e3] electronic configuration, not [a2e1], with the a(z2) antibonding orbital substantially higher in energy than the e[xz, yz] orbitals.
Contact Mode Guided Motion Planning for Quasidynamic Dexterous Manipulation in 3D (2021)

This paper presents Contact Mode Guided Manipulation Planning (CMGMP) for 3D quasistatic and quasidynamic rigid body motion planning in dexterous manipulation. The CMGMP algorithm generates hybrid motion plans including both continuous state transitions and discrete contact mode switches, without the need for pre-specified contact sequences or pre-designed motion primitives. The key idea is to use automatically enumerated contact modes of environment-object contacts to guide the tree expansions during the search. Contact modes automatically synthesize manipulation primitives, while the sampling-based planning framework sequences those primitives into a coherent plan. We test our algorithm on fourteen 3D manipulation tasks, and validate our models by executing some plans open-loop on a real robot-manipulator system
Thin-film sensing with Terahertz split-ring resonators (2008)

We investigate the limitations of using THz metamaterials as thin-film chem-bio sensors, by depositing dielectric overlayers onto split-ring resonator arrays. We also study resonance shifts by conjugating biomolecules using avidin/silane linkers attached to the resonators.
Coefficient dither in fixed-point fir digital filters (2008)

This paper presents dynamic coefficient dither as a method to mitigate coefficient quantization error in FIR filters. The uncorrelated, shapeable noise from dithered coefficients may be preferable, in certain contexts, to the frequency response distortion due to static fixed-point implementation. A theoretical framework for the analysis of coefficient dither is developed. Performance, fundamental tradeoffs, and optimization of dithered filter implementations are discussed. Oversampling is shown to improve the SNR. The theoretical results are validated with numerical experiments.
Simple highly modular acyclic amine-catalyzed direct enantioselective addition of ketones to nitro-olefins (2006)

Simple, highly modular primary amino acid derivatives catalyze the direct enantioselective addition of ketones to nitro-olefins with high stereocontrol and furnish the corresponding aldol products in high yield with up to >38 1 dr and up to 99% ee.
Evaluation of Daily GI Symptoms in a Phase 2A Study of IW-9179 in Functional Dyspepsia (2014)

Introduction: Patients with functional dyspepsia (FD) often have symptoms common to comorbid GI disorders. We evaluated daily symptoms of irritable bowel syndrome (IBS), functional diarrhea (FDia), functional constipation (FC), and gastroesophageal reflux disease (GERD) during a 14-day pretreatment period (PP) of a phase 2a study of the treatment effect of an investigational guanylate cyclase C agonist, IW-9179, in FD patients. Methods: Patients who met Rome III FD criteria (symptoms: postprandial fullness, early satiation, epigastric pain, epigastric burning, epigastric bloating, nausea, belching) without history of IBS, FDia, FC, or GERD took part in the PP. Patients eligible after PP were randomized 1:1 to receive oral 500 μg IW-9179 or placebo (PBO) once a day for 2 weeks. Patients assessed symptom severity (PSS) and bowel habits (BH) daily. Results: Fifty-eight of 110 screened patients entered the PP and completed ≥10 days of PSS and BH assessments. Despite excluding history of overlapping GI disorders, non-FD GI symptoms among FD patients were common (Table 1), with GERD resulting in most patient ineligibility for randomization; only 13 patients (22%) did not meet symptomatic criteria for any overlapping GI disorders. Ten of these 13 patients were randomized (ITT: 4 PBO, 6 IW-9179). Daily PSS results showed numerically greater improvement from baseline for IW-9179- vs PBO-treated patients in 6 of 7 FD symptoms (Table 2); only epigastric burning showed a change from baseline greater in PBO than IW-9179. Diarrhea was the most common AE in IW-9179 patients.Table 1: GI Disorders Overlapping With FDTable 2: Change From Baseline in PSSConclusion: In this population, there was significant overlap between FD and other GI disorders, particularly GERD. Although the sample size was small, modest improvement in FD symptoms vs PBO was observed for IW-9179, supporting further evaluation of this agent. Disclosure - J Tack is a consultant to Ironwood Pharma. DA Fitch, JZ Shao, CR O’Dea, MG Currie, and JM Johnston are employees of Ironwood Pharma. This research was supported by an industry grant from Ironwood Pharma.
Genetic manipulation of immortalized normal human bronchial epithelial cells (2005)

3896 Purpose: To evaluate the oncogenic impact of p53 knockdown, mutant K-RASV12, mutant EGFR alone and their combination on tumorigenicity of a newly developed immortalized human bronchial epithelial cell line. Background: Molecular analysis of lung cancer has revealed several genetic and epigenetic alterations in the multistep pathogenesis of lung cancer. However, little is known about the relative importance of each individual alteration on the tumorigenic process. One approach is to use a model system in which the contribution of each genetic alteration to lung tumorigenesis can be assessed individually and combinatorially. We have developed an in vitro model system using normal human bronchial epithelial cells that overexpress Cyclin-dependent kinase 4 and human telomerase. Ectopic expression of these two genes enables the cells to bypass the growth inhibitory signals of the p16/Rb pathway and also replicative senescence induced by shortened telomeres. We manipulated this cell line (HBEC3), by stably knocking down p53 using RNA interference, by introducing a mutant form of K-RASV12, and by introducing a mutant epidermal growth factor receptor (EGFR), alone and in combination. Methods: pSuper.retro vector was used for p53 knockdown and a mutant K-RASV12 and mutant EGFRs (EGFRdel746-750 and EGFRL858R) were introduced using viral expression vectors. To test the genetically manipulated lines for changes in their malignant potential, growth in liquid culture, colony formation ability, growth factor dependence, and growth as xenografts in immuno-compromised mice were performed. To determine the effect of tyrosine kinase inhibitors (TKIs) (gefitinib and erlotinib) on manipulated HBEC3 cells and to assess their potential as chemopreventive agents, the cells were evaluated both in the presence or absence of these drugs for colony forming ability. Results: Stable knockdown of p53 and overexpression of mutant EGFR were confirmed by immunoblotting in manipulated cells. K-RASV12 expression was confirmed by RFLP analysis. p53 knockdown and K-RASV12 alone caused cells to be less sensitive to contact inhibition and to be capable of partial anchorage-independent growth. The combination of p53 knockdown and K-RASV12 further enhanced the tumorigenic phenotype by growth in soft agar but failed to cause cells to form tumors in nude mice. In addition, the ability of both anchorage-dependent and-independent cell growth of HBEC3 cells was highly dependent on epidermal growth factor (EGF) and this ability was completely inhibited with TKIs. Both types of mutant EGFRs enhanced the tumorigenic phenotype by growth in soft agar. Importantly, introduction of mutant EGFRL858R into the HBEC3-p53 knockdown cells abrogated EGF dependence as measured by anchorage-independent colony formation ability. These results demonstrate that this isogenic in vitro model system is a powerful approach for studying lung cancer development.
Quantizing Convolutional Neural Networks for Low-Power High-Throughput Inference Engines (2018)

Deep learning as a means to inferencing has proliferated thanks to its versatility and ability to approach or exceed human-level accuracy. These computational models have seemingly insatiable appetites for computational resources not only while training, but also when deployed at scales ranging from data centers all the way down to embedded devices. As such, increasing consideration is being made to maximize the computational efficiency given limited hardware and energy resources and, as a result, inferencing with reduced precision has emerged as a viable alternative to the IEEE 754 Standard for Floating-Point Arithmetic. We propose a quantization scheme that allows inferencing to be carried out using arithmetic that is fundamentally more efficient when compared to even half-precision floating-point. Our quantization procedure is significant in that we determine our quantization scheme parameters by calibrating against its reference floating-point model using a single inference batch rather than (re)training and achieve end-to-end post quantization accuracies comparable to the reference model.
Design of nanomanufacturing systems (2010)

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2010.