gebhart/patrepeval huggingface dataset:
Oxygen Monitoring in Model Solutions and In Vivo in Mice During Proton Irradiation at Conventional and FLASH Dose Rates (2022)

FLASH is a high-dose-rate form of radiation therapy that has the reported ability, compared with conventional dose rates, to spare normal tissues while being equipotent in tumor control, thereby increasing the therapeutic ratio. The mechanism underlying this normal tissue sparing effect is currently unknown, however one possibility is radiochemical oxygen depletion (ROD) during dose delivery in tissue at FLASH dose rates. In order to investigate this possibility, we used the phosphorescence quenching method to measure oxygen partial pressure before, during and after proton radiation delivery in model solutions and in normal muscle and sarcoma tumors in mice, at both conventional (Conv) (∼0.5 Gy/s) and FLASH (∼100 Gy/s) dose rates. Radiation dosimetry was determined by Advanced Markus Chamber and EBT-XL film. For solutions contained in sealed glass vials, phosphorescent probe Oxyphor PtG4 (1 µM) was dissolved in a buffer (10 mM HEPES) containing glycerol (1 M), glucose (5 mM) and glutathione (5 mM), designed to mimic the reducing and free radical-scavenging nature of the intracellular environment. In vivo oxygen measurements were performed 24 h after injection of PtG4 into the interstitial space of either normal thigh muscle or subcutaneous sarcoma tumors in mice. The "g-value" for ROD is reported in mmHg/Gy, which represents a slight modification of the more standard chemical definition (µM/Gy). In solutions, proton irradiation at conventional dose rates resulted in a g-value for ROD of up to 0.55 mmHg/Gy, consistent with earlier studies using X or gamma rays. At FLASH dose rates, the g-value for ROD was ∼25% lower, 0.37 mmHg/Gy. pO2 levels were stable after each dose delivery. For normal muscle in vivo, oxygen depletion during irradiation was counterbalanced by resupply from the vasculature. This process was fast enough to maintain tissue pO2 virtually unchanged at Conv dose rates. However, during FLASH irradiation there was a stepwise decrease in pO2 (g-value ∼0.28 mmHg/Gy), followed by a rebound to the initial level after ∼8 s. The g-values were smaller and recovery times longer in tumor tissue when compared to muscle and may be related to the lower initial endogenous pO2 levels in the former. Considering that the FLASH effect is seen in vivo even at doses as low as 10 Gy, it is difficult to reconcile the amount of protection seen by oxygen depletion alone. However, the phosphorescence probe in our experiments was confined to the extracellular space, and it remains possible that intracellular oxygen depletion was greater than observed herein. In cell-mimicking solutions the oxygen depletion g-vales were indeed significantly higher than observed in vivo.
Spectroscopic ellipsometry from the vacuum ultraviolet to the far infrared (2001)

Spectroscopic ellipsometry is an important thin film metrology technique. It offers non-destructive and non-invasive materials characterization, including measurement of the complex refractive index and other microstructural properties that affect the material optical response. It has been applied to many important ultra large scale integration (ULSI) thin-film metrology needs; as it is applicable to semiconductors, dielectrics, metals, organic films, and more. Recent advances have broadened the impact of ellipsometry for many applications. New instruments are extending the spectral range to both shorter and longer wavelengths. High-speed spectroscopic measurements can be accomplished with diode-array technology. In addition to hardware advances, new data analysis techniques have extended the capabilities of spectroscopic ellipsometry. The advanced capabilities of spectroscopic ellipsometry will be reviewed, including the importance of new spectral ranges in the vacuum ultra-violet (VUV) and infrared (IR). The merit of fast measurements for in-line and in-situ measurements is covered. New data analysis methods are discussed, with their possible applications toward ULSI thin film metrology. In short, this paper reviews the progress of hardware and data analysis innovations and their impact on ULSI thin film metrology.
Enabling low loss thin glass solutions for 5G / mmWave applications (2021)

In this paper, we describe progress in via-formation and processing of thin glass substrates. An advanced temporary bonding approach enables easy handling of thin glass substrates through TGV fill, as well as aggressive downstream processes such as CMP. The formation of TGVs in both aluminoborosilicate and fused silica is discussed, and hermetic, filled vias are successfully demonstrated. Promising simulation results on fused silica validate the usefulness of glass structures in millimeter-wave-frequency antennas.
Emergence of Liquid Metals in Nanotechnology (2019)

Bulk liquid metals have prospective applications as soft and fluid electrical and thermal conductors in electronic and optical devices, composites, microfluidics, robotics, and metallurgy with unique opportunities for processing, chemistry, and function. Yet liquid metals' great potential in nanotechnology remains in its infancy. Although work to date focuses primarily on Ga, Hg, and their alloys, to expand the field, we define "liquid metals" as metals and alloys with melting points (mp) up to 330 °C, readily accessible and processable even using household kitchen appliances. Such a definition encompasses a family of metals-including the majority of post-transition metals and Zn group elements (excluding Zn itself)-with remarkable versatility in chemistry, physics, and engineering. These liquid alloys can create metallic compounds of different morphologies, compositions, and properties, thereby enabling control over nanoscale phenomena. In addition, the presence of electronic and ionic "pools" within the bulk of liquid metals, as well as deviation from classical metallurgy on the surfaces of liquid metals, provides opportunities for gaining new capabilities in nanotechnology. For example, the bulk and surfaces of liquid metals can be used as reaction media for creating and manipulating nanomaterials, promoting reactions, or controlling crystallization of dissolved species. Interestingly, liquid metals have enormous surface tensions, yet the tension can be tuned electrically over a wide range or modified <i>via</i> surface species, such as the native oxides. The ability to control the interfacial tension allows these liquids to be readily reduced in size to the nanoscale. The liquid nature of such nanoparticles enables shape-reconfigurable structures, the creation of soft metallic nanocomposites, and the dissolution or dispersion of other materials within (or on) the metal to produce multiphasic or heterostructure particles. This Perspective highlights the salient features of these materials and seeks to raise awareness of future opportunities to understand and to utilize liquid metals for nanotechnology.
In vivo correction of ZAP-70 immunodeficiency by intrathymic gene transfer (2005)

SCID patients have been successfully treated by administration of ex vivo gene-corrected stem cells. However, despite its proven efficacy, such treatment carries specific risks and difficulties. We hypothesized that some of these drawbacks may be overcome by in situ gene correction of T lymphoid progenitors in the thymus. Indeed, in vivo intrathymic transfer of a gene that provides a selective advantage for transduced prothymocytes should result in the generation of functional T lymphocyte progeny, allowing long-term immune reconstitution. We assessed the feasibility of this approach in a murine model of ZAP-70-deficient SCID. A T cell-specific ZAP-70-expressing lentiviral vector was injected into thymi of adult ZAP-70-/- mice without prior conditioning. This resulted in the long-term differentiation of mature TCR-alphabeta+ thymocytes, indicating that the vector had integrated into progenitor cells. Moreover, peripheral ZAP-70-expressing T cells demonstrated a partially diversified receptor repertoire and were responsive to alloantigens in vitro and in vivo. Improved treatment efficacy was achieved in infant ZAP-70-/- mice, in which the thymus is proportionately larger and a higher percentage of prothymocytes are in cycle. Thus, intrathymic injection of a lentiviral vector could represent a simplified and potentially safer alternative to ex vivo gene-modified hematopoietic stem cell transplantation for gene therapy of T cell immunodeficiencies.
Risk Factors for Readmission with Cerebrospinal Fluid Leakage Within 30 Days of Vestibular Schwannoma Surgery (2017)

This study has quantified CSF leak as an important contributor to nearly half of all readmissions following vestibular schwannoma surgery. We propose that surgeons should focus on technical factors that may reduce CSF leakage and take advantage of potential screening strategies for the detection of CSF leakage prior to first admission discharge.
System-level Trade-offs and Optimization for Data-Driven Applications (2018)

Abstract Data-driven applications are becoming increasingly important, fueled by the rapid rise of the Internet of Things (IoT) and Artificial Intelligence (AI). Systems must now be able to store, process and act swiftly on increasingly large amounts of data, while consuming minimum possible power. This shifts the focus to system-level integration and optimization – especially as Moore's Law slows down, and technology development at 5nm and beyond becomes increasingly harder and more expensive. SEMI has built a cross-supply-chain collaborative platform specifically to enable an early assessment of trade-offs and future technologies (5–8 years out). The first project focused on interconnect strategies, which are critical to most computing systems. We examined the performance limits for the best possible options for on-chip interconnects at technology nodes &amp;lt;= 20 nm. These limits highlight the need for system-level strategies, and we studied these by comparing a two-dimensional (2D) system with an interposer-based system (2.5D) to quantify the impact of the latter on the energy-delay product for various applications, especially data-driven ones.
Therapeutic nanoworms: towards novel synthetic dendritic cells for immunotherapy (2013)

A new class of antibody-functionalized, semi-flexible and filamentous polymers (diameter 5–10 nm, length ∼200 nm) with a controlled persistence length, a high degree of stereoregularity and the potential for multiple simultaneous receptor interactions has been developed. We have decorated these highly controlled, semi-stiff polymers with T cell activating anti-CD3 antibodies and analyzed their application potential as simple synthetic mimics of dendritic cells (sDCs). Our sDCs do not only activate T cells at significantly lower concentrations than free antibodies or rigid sphere-like counterparts (PLGA particles) but also induce a more robust T cell response. Our novel design further yields sDCs that are biocompatible and non-toxic. The observed increased efficacy highlights the importance of architectural flexibility and multivalency for modulating T cell response and cellular function in general.
Reheating an Inflationary Universe (1982)

A numerical analysis of the evolution of the Higgs expectation value and the temperature of the universe during the symmetry-breaking phase transition in an SU(5) theory with radiatively induced symmetry breaking is presented. It is shown that there is sufficient inflation (exponential expansion) to explain the cosmological homogeneity, isotropy, flatness, and monopole puzzles, and also that the universe reheats to a temperature $O({10}^{14} \mathrm{GeV})$ so that the usual scheme for baryogenesis can proceed.
Deletion of Fn14 receptor protects from right heart fibrosis and dysfunction (2013)

Pulmonary arterial hypertension (PAH) is a fatal disease for which no cure is yet available. The leading cause of death in PAH is right ventricular (RV) failure. Previously, the TNF receptor superfamily member fibroblast growth factor-inducible molecule 14 (Fn14) has been associated with different fibrotic diseases. However, so far there is no study demonstrating a causal role for endogenous Fn14 signaling in RV or LV heart disease. The purpose of this study was to determine whether global ablation of Fn14 prevents RV fibrosis and remodeling improving heart function. Here, we provide evidence for a causative role of Fn14 in pulmonary artery banding (PAB)-induced RV fibrosis and dysfunction in mice. Fn14 expression was increased in the RV after PAB. Mice lacking Fn14 (Fn14(-/-)) displayed substantially reduced RV fibrosis and dysfunction following PAB compared to wild-type littermates. Cell culture experiments demonstrated that activation of Fn14 induces collagen expression via RhoA-dependent nuclear translocation of myocardin-related transcription factor-A (MRTF-A)/MAL. Furthermore, activation of Fn14 in vitro caused fibroblast proliferation and myofibroblast differentiation, which corresponds to suppression of PAB-induced RV fibrosis in Fn14(-/-) mice. Moreover, our findings suggest that Fn14 expression is regulated by endothelin-1 (ET-1) in cardiac fibroblasts. We conclude that Fn14 is an endogenous key regulator in cardiac fibrosis and suggest this receptor as potential new target for therapeutic interventions in heart failure.
Extension of the ITU channel models for wideband (OFDM) systems (2006)

This paper outlines a procedure to extend, or upsample, the ITU power delay profiles (PDP) to improve the frequency correlation properties while keeping the same mean delay and almost the same rms delay spread. Realistic frequency correlation properties are of particular importance for the evaluation of wideband system concepts with frequency dependent characteristics, e.g. frequency domain link adaptation and packet scheduling, both of which are likely to be part of future wideband systems such as based on OFDM. With the suggested procedure the frequency correlation can be kept approximately at or below 0.6 for frequency separations up to 25 MHz for the exemplified ITU Vehicular A and Pedestrian B channel profiles. The compatibility in terms of link level performance with WCDMA rake processing and the representation of the profiles on different sampling grids is briefly discussed in the paper. ITU Channel models; frequency correlation function; wideband systems; power delay profile; beyond 3G system concepts
The Effect of Covariance Structure on Variance Estimation in Balanced Growth-Curve Models with Random Parameters (1989)

Abstract Intuition suggests that altering the covariance structure of a parametric model for repeated-measures data alters the variances of the model's estimated mean parameters. The purpose of this article is to sharpen such intuition for a family of growth-curve models with differing numbers of random effects for the individual sampling units and with a fixed structure on the mean. For every member of this family, the maximum likelihood (ML) estimator of the fixed effects is identical to the ordinary least squares (OLS) estimator. In addition, simple closed-form ML and restricted maximum likelihood estimators for the variance and covariance parameters exist for every member. As a consequence, closed-form expressions for the estimated variance-covariance matrix of the OLS estimator of the fixed effects also exist for the entire family. We derive explicit relationships between the variance and covariance parameter estimators from different members of the family and thereby extend some familiar results. For example, it is well known that for balanced and complete longitudinal designs the compound symmetry assumption for the covariance structure of the serial observations (i.e., assuming one random effect for each sampling unit) yields a more precise estimate of the slope of the population growth curve than of its intercept. It is also well known that for such designs the diagonal covariance structure assumption of OLS regression (i.e., no random effects for the units) yields a more precise estimate of the intercept than does the compound symmetry assumption, and a less precise estimate of the slope. We extend such relationships as these to growth-curve models whose covariance structures are of increasing linear complexity (i.e., assuming two or more random effects for each of the sampling units). We find that, in general, the variance of the OLS estimator depends strongly on assumed covariance structure. We also find that, specifically, the linear growth-curve assumption (i.e., two random effects for each sampling unit) is a conservative assumption, in that such will not give misleadingly small variance estimates for both intercept and slope even if a more complex covariance structure actually holds. We illustrate these points with a data example. In the conclusion, we extend our results by showing how they may apply to more general families of balanced growth-curve models that allow wider ranges of covariance structures and designs for the random effects, such as when different population subgroups require different covariance structures. We also address several computational issues involved in transformations of growth-curve models to canonical form.
Organic solar cell strategy and developments in Flanders (2006)

IMEC started up its activity on organic solar cells in 1998 and since 2005 this topic became one of the key technologies of the Flemish Innovation Policy in the field of Photovoltaics. The aim of the paper is to present the overall Flemish approach and strategy to this field as well as to highlight the recent achievements of the Organic Photovoltaics Technology Program. The strategy of this program is built around three focal points: enhancement of the conversion efficiency, improvement of the cell stability and development of a printing technology to realize monolithic modules on a flexible foil. This strategy is being executed mainly within IMEC with its large expertise in the field of solar cell technology development and its associated lab, IMOMEC, and the University of Hasselt which has a strong background in synthesis and characterization of conjugated polymers. In addition, there is considerable
Effect of long-term food restriction on pituitary sensitivity to cLHRH-I in broiler breeder females (1998)

The effect of long-term food restriction on the sensitivity of the pituitary to exogenously administered chicken luteinizing hormone releasing hormone I (cLHRH-I) was investigated in three groups of broiler breeder females fed ad libitum, fed a restricted quantity of food or fed a restricted quantity of food to obtain an intermediate body weight between those of the first two groups. At 16 weeks of age, basal FSH release was higher in ad libitum fed birds, culminating in ovarian development and subsequent oestradiol production by the small follicles. At this age, LH secretion was independent of ovarian feedback factors. In all groups, cLHRH-I was most active in releasing LH in intact and ovariectomized animals and, to a lesser extent, in releasing FSH in ovariectomized birds. At 39 weeks of age, basal FSH concentrations were similar among intact animals of all groups, whereas LH concentrations differed among groups, with higher values in the restricted birds. This food effect was enhanced in ovariectomized birds. Furthermore, the high response to cLHRH-I in the ovariectomized, restricted birds compared with the ad libitum, ovariectomized group suggests an improved sensitivity of the hypothalamic-pituitary axis. In conclusion, birds fed ad libitum showed the highest responsiveness to ovarian factors and to cLHRH-I in releasing FSH in the period before sexual maturity. No effect of amount of feeding could be observed for LH. However, during the egg laying period, LH release by cLHRH-I was highly dependent on amount of feeding and on ovarian feedback regulation. This finding indicates that the amount of feeding can modify the sensitivity of the pituitary to cLHRH-I, and possibly to gonadal hormones, during the laying period.
A rapid prototyping methodology to implement and optimize image processing algorithms for FPGAs (2006)

In this article we present the local operations in image processing based upon spatial 2D discrete convolution. We study different implementation of such local operations. We also present the principles and the design flow of the AAA methodology and its associated CAD software tool for integrated circuit (SynDEx-IC). In this methodology, the algorithm is modeled by Conditioned (if - then - else) and Factorized (Loop) Data Dependence Graph and the optimized implementation is obtained by graph transformations. The AAA/SynDEx-IC is used to specify and to optimize the some digital image filters on FPGA XC2100 board.
Engineering an Effective Human SNAP-23 Cleaving Botulinum Neurotoxin A Variant (2020)

Botulinum neurotoxin (BoNT) serotype A inhibits neurotransmitter release by cleaving SNAP-25 and represents an established pharmaceutical for treating medical conditions caused by hyperactivity of cholinergic nerves. Oversecretion from non-neuronal cells is often also the cause of diseases. Notably, excessive release of inflammatory messengers is thought to contribute to diseases such as chronic obstructive pulmonary disease, asthma, diabetes etc. The expansion of its application to these medical conditions is prevented because the major non-neuronal SNAP-25 isoform responsible for exocytosis, SNAP-23, is, in humans, virtually resistant to BoNT/A. Based on previous structural data and mutagenesis studies of SNAP-23 we optimized substrate binding pockets of the enzymatic domain for interaction with SNAP-23. Systematic mutagenesis and rational design yielded the mutations E148Y, K166F, S254A, and G305D, each of which individually increased the activity of LC/A against SNAP-23 between 3- to 23-fold. The assembled quadruple mutant showed approximately 2000-fold increased catalytic activity against human SNAP-23 in in vitro cleavage assays. A comparable increase in activity was recorded for the full-length BoNT/A quadruple mutant tested in cultivated primary neurons transduced with a fluorescently tagged-SNAP-23 encoding gene. Equipped with a suitable targeting domain this quadruple mutant promises to complete successfully tests in cells of the immune system.
Building Manycore Processor-to-DRAM Networks with Monolithic Silicon Photonics (2008)

We present a new monolithic silicon photonics technology suited for integration with standard bulk CMOS processes, which reduces costs and improves opto-electrical coupling compared to previous approaches. Our technology supports dense wavelength-division multiplexing with dozens of wavelengths per waveguide. Simulation and experimental results reveal an order of magnitude better energy-efficiency than electrical links in the same technology generation. Exploiting key features of our photonics technology, we have developed a processor-memory network architecture for future manycore systems based on an opto-electrical global crossbar. We illustrate the advantages of the proposed network architecture using analytical models and simulations with synthetic traffic patterns. For a power-constrained system with 256 cores connected to 16 DRAM modules using an opto-electrical crossbar, aggregate network throughput can be improved by ap8-10times compared to an optimized purely electrical network.
ChemInform Abstract: Tetrahydrofuran α‐Azido Esters: Precursors of Anomeric α‐Amino Acid Monomers via Radical Bromination. (1999)

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.