gebhart/patrepeval huggingface dataset:
Photochemical Nitration by Tetranitromethane. Part XXVI. Adduct Formation in the Photochemical Reaction of 1,2,3-Trimethylbenzene: the Formation of 'Double' Adducts Including Nitronic Esters. (1996)

The photolysis of the charge-transfer complex of 1,2,3-trimethylbenzene and tetranitromethane gives a complex mixture of products, most of which arise by initial attack of trinitromethanide ion on the unsubstituted ring positions at C4(C6) and C5 of the radical cation of 1,2,3-trimethylbenzene. The products 7-19 are adducts resulting directly or indirectly from the addition of the elements of tetranitromethane to 1,2,3-trimethylbenzene, and the trinitromethyl aromatic compounds 22-25 are formed by eliminations from intermediate adducts. Six adducts are simple 'single' adducts, nitro-trinitromethyl adducts 7, 8, 10-12, while nitro cycloadduct 9 is formed by cycloaddition of nitro-trinitromethyl adduct 8. The remaining addition products are 'double' adducts, formed by secondary addition reactions initiated by attack of nitrogen dioxide on the buta-1,3-diene system of 'single' adducts, and include trinitro-trinitromethyl compounds 13 and 15, the hydroxy-dinitro-trinitromethyl compound 14, and a group of four nitronic esters 16-19 formed by nitro-denitrocyclization of initially formed hydroxy-trinitromethyl and nitro-trinitromethyl 'single' adducts. Minor amounts of other products are formed including two nitrodienones 21 and 22, and the rearrangement product, 4,5,6-trimethyl-2-nitrophenol (28), and the 2,3,4-trimethyl- and 3,4,5-trimethylnitrobenzenes 26 and 27. The modes of formation of the above products are discussed, and X-ray crystal structure determinations are reported for compounds 9, 13, 14, 18, 19, 22 and 29.
Synchrotron macro ATR-FTIR microspectroscopic analysis of silica nanoparticle-embedded polyester coated steel surfaces subjected to prolonged UV and humidity exposure (2017)

Surface modification of polymers and paints is a popular and effective way to enhance the properties of these materials. This can be achieved by introducing a thin coating that preserves the bulk properties of the material, while protecting it from environmental exposure. Suitable materials for such coating technologies are inorganic oxides, such as alumina, titania and silica; however, the fate of these materials during long-term environmental exposure is an open question. In this study, polymer coatings that had been enhanced with the addition of silica nanoparticles (SiO2NPs) and subsequently subjected to environmental exposure, were characterized both before and after the exposure to determine any structural changes resulting from the exposure. High-resolution synchrotron macro ATR-FTIR microspectroscopy and surface topographic techniques, including optical profilometry and atomic force microscopy (AFM), were used to determine the long-term effect of the environment on these dual protection layers after 3 years of exposure to tropical and sub-tropical climates in Singapore and Queensland (Australia). Principal component analysis (PCA) based on the synchrotron macro ATR-FTIR spectral data revealed that, for the 9% (w/w) SiO2NP/polymer coating, a clear discrimination was observed between the control group (no environmental exposure) and those samples subjected to three years of environmental exposure in both Singapore and Queensland. The PCA loading plots indicated that, over the three year exposure period, a major change occurred in the triazine ring vibration in the melamine resins. This can be attributed to the triazine ring being very sensitive to hydrolysis under the high humidity conditions in tropical/sub-tropical environments. This work provides the first direct molecular evidence, acquired using a high-resolution mapping technique, of the climate-induced chemical evolution of a polyester coating. The observed changes in the surface topography of the coating are consistent with the changes in chemical composition.
Transplacental and Other Routes of Cancer Transmission Between Individuals (2003)

Cancer in pregnancy is not rare, and the possibility of transmission of malignancy from mother to child, while infrequent, represents a clinical challenge for the primary pediatric hematologist-oncologist. The authors summarize all reported cases of vertically transmitted cancer and review other reported cases of person-to-person transfer of malignancy. As these cases represent a unique physiologic model of tumor transplantation, the biology of cancer transmission is discussed and provisional guidelines are given for the screening of infants born to women with cancer.
Towards Theoretical Bounds for Resource-bounded Information Gathering for Correlation Clustering (2009)

Resource-bounded Information Gathering for Correlation Clustering deals with designing efficient methods for obtaining and incorporating information from external sources to improve accuracy of clustering tasks. In this paper, we formulate the problem, and some specific goals and lay the foundation for better theoretical understanding of this framework. We address the challenging problem of analytically quantifying the effect of changing a single edge weight on the partitioning of the entire graph, under some simplifying assumptions, hence demonstrating a method to calculate the expected reduction in error. Our analysis of different query selection criteria provides a formal way of comparing different heuristics. We compare the solution of our theoretical analysis with simulation results. We also estimate the probability of recovering the true partition under various query selection strategies for general random graphs and discuss some possible directions for approximation. Next, we prove a related bound under certain assumptions. We also describe some general techniques to efficiently query and select nodes for expanding graphs.
Development &amp; performance assessment of a new ATMP for cartilage tissue engineering (2016)

Frontiers Events is a rapidly growing calendar management system dedicated to the scheduling of academic events. This includes announcements and invitations, participant listings and search functionality, abstract handling and publication, related events and post-event exchanges. Whether an organizer or participant, make your event a Frontiers Event!
High Temperature Characterization of 4H-SiC Bipolar Junction Transistors (2006)

This paper summarizes the recent demonstration of 3200 V, 10 A BJT devices with a high common emitter current gain of 44 in the linear region, and a specific on-resistance of 8.1 mΩ- cm2 (10 A at 0.90 V with a base current of 350 mA and an active area of 0.09 cm2). The onresistance increases to 40 mΩ-cm2 at 350°C, while the DC current gain decreases to 30. A sharp avalanche behavior was observed with a leakage current of 10 μA at a collector voltage of 3.2 kV.
Feedforward Effect in Standard (2013)

The charge handling capacity or the full well of the photodiodes used in CMOS image sensors is a very important characteristic because it affects the saturation level and the dy- namic range of the image sensor. The scaling of the pixel size to increase the spatial resolution is also reducing the barrier separating the photon detection and the collection node in a standard pinned photodiode (PPD). The barrier reduction and the thermionic emission of the electrons allow some of the charges from the photodiode well to feed into the collection node, resulting in a feedforward voltage. In conventional readout of the pixels, this feedforward voltage is neglected and lost when the collection node is reset. The barrier height of the transfer gate (TG) deter- mines the quantity of electrons held back in the photodiode well. Thus, the knowledge of this barrier height is very important in determining the true charge handling capacity of the photodiode potential well. Experiments with standard PPDs showed that a barrier height of around 0.5 V is needed to hold the electrons in the photodiode potential well. This is analogous to the barrier potential for charge-coupled devices reported in the literature. Furthermore, the barrier height dependence on the charge storing time in the photodiode well and the structural dimensions of the TG and photodiode length are also explored in this paper.
Anxiety and Depression Symptoms and Response to Methylphenidate in Children With Attention-Deficit Hyperactivity Disorder and Tic Disorder (2002)

This study examined response to methylphenidate in children with attention-deficit/hyperactivity disorder (ADHD) and chronic multiple tic disorder. The primary goal was to determine if children with anxiety or depression symptoms showed a less favorable response to treatment. Subjects were 38 prepubertal children who participated in an 8-week, double-blind, placebo-controlled, methylphenidate crossover evaluation. Treatment effects were assessed with direct observations of child behavior in public school and clinic settings; rating scales completed by parents, teachers, and clinicians; and laboratory analogue tasks. There was little evidence (group data) that children with anxiety or depression symptoms responded in a clinically different manner to methylphenidate than youngsters who did not exhibit these symptoms, particularly in school observations of the core features of ADHD. Seeming differences between children with and without comorbid anxiety or depression symptoms and drug response are likely explained by differences in pretreatment levels of negativistic behaviors (i.e., symptoms of oppositional defiant disorder or conduct disorder). Methylphenidate appears to be effective for the management of ADHD behaviors in children with mild to moderate anxiety or depression symptoms; nevertheless, much research remains to be performed in this area.
Recognition competes with hydration in anion-triggered monolayer formation of cyanostar supra-amphiphiles at aqueous interfaces (2022)

The triggered self-assembly of surfactants into organized layers at aqueous interfaces is important for creating adaptive nanosystems and understanding selective ion extraction. While these transformations require molecular recognition, the underlying driving forces are modified by the local environment in ways that are not well understood. Herein, we investigate the role of ion binding and ion hydration using cyanosurf, which is composed of the cyanostar macrocycle, and its binding to anions that are either size-matched or mis-matched and either weakly or highly hydrated. We utilize the supra-amphiphile concept where anion binding converts cyanosurf into a charged and amphiphilic complex triggering its self-organization into monolayers at the air-water interface. Initially, cyanosurf forms aggregates at the surface of a pure water solution. When the weakly hydrated and size-matched hexafluorophosphate (PF<sub>6</sub> <sup>-</sup>) and perchlorate (ClO<sub>4</sub> <sup>-</sup>) anions are added, the macrocycles form distinct monolayer architectures. Surface-pressure isotherms reveal significant reorganization of the surface-active molecules upon anion binding while infrared reflection absorption spectroscopy show the ion-bound complexes are well ordered at the interface. Vibrational sum frequency generation spectroscopy shows the water molecules in the interfacial region are highly ordered in response to the charged monolayer of cyanosurf complexes. Consistent with the importance of recognition, we find the smaller mis-matched chloride does not trigger the transformation. However, the size-matched phosphate (H<sub>2</sub>PO<sub>4</sub> <sup>-</sup>) also does not trigger monolayer formation indicating hydration inhibits its interfacial binding. These studies reveal how anion-selective recognition and hydration both control the binding and thus the switching of a responsive molecular interface.
Botulinum Neurotoxin-Producing Bacteria. Isn’t It Time that We Called a Species a Species? (2018)

Botulinum neurotoxins (BoNTs) are produced by a diverse set of seven clostridial species, though alternate naming systems have developed over the last 100 years. Starting in the 1950s, a single-species taxonomy where any bacterium producing BoNT would be designated <i>Clostridium botulinum</i> was introduced. As the extreme diversity of these strains was recognized, a secondary system of taxonomic "groups" evolved. It became clear that these groups also had members that did not produce BoNT, and in some cases, they were given formal species names. Genomic analysis now clearly identifies species affiliations whether an isolate is toxigenic or not. It is clear that <i>C. botulinum</i> group nomenclature is no longer appropriate and that there are recognized species names for each clostridium. We advocate for the use of the scientific binomials and that the single-species group nomenclature be abandoned.
Thymic carcinoid in association with MEN syndromes. (1992)

Although carcinoid tumors in association with multiple endocrine neoplasia syndrome (MEN) has been well described, thymic carcinoid in association with MEN is extremely rare (only 23 cases in the world literature). A patient with thymic carcinoid and MEN-I was treated with surgical resection and postoperative radiation therapy, which was later followed by subtotal parathyroidectomy for hyperparathyroidism. Four years later, a symptomatic recurrence of his thymic carcinoid was resected from below his right clavicle. Six years after his original operation, the patient came to the hospital with pancreatitis, and a 5 cm, distal, pancreatic metastasis was resected. He now has symptomatic paraspinal and pleural metastases and is receiving somatostatin. Review of the world's literature shows that the majority of patients with thymic carcinoid and MEN-I are men with an average age of 37 years. Their clinical course is indolent, and surgery represents the only means of cure. Adjuvant chemotherapy and radiation therapy confer no survival advantage. The surgical decision making involved in treating a patient with thymic carcinoid and hyperparathyroidism associated with MEN is also discussed.
Experimental Study of Interactions Between Suboxidized Corium and Reactor Vessel Steel (2006)

One of the critical factors in the analysis of in-vessel melt retention is the vessel strength. It is, in particular, sensitive to the thickness of intact vessel wall, which, in its turn, depends on the thermal conditions and physicochemical interactions with corium. \nPhysicochemical interaction of prototypic UO2-ZrO2-Zr corium melt and VVER vessel steel was examined during the 2nd Phase of the ISTC METCOR Project.
Impact of Calcium on the Membrane Fouling in Membrane Bioreactors (2007)

Impact of Calcium on the Membrane Fouling in Membrane BioreactorsFouling in submerged membrane bioreactors (MBRs) was studied under two calcium levels (280 and 830 mg/L). Two MBRs were operated on synthetic municipal wastewater at a solids retention time (SRT) of 15 days, a control at a calcium level of around 35 mg/L and a test reactor at two calcium levels of 280 and 830 mg/L. Permeability, flux, extracellular polymeric substances (EPS), Ca2+ concentration...Author(s)Sara ArabiGeorge NakhlaSourceProceedings of the Water Environment FederationSubjectSession 82: Overcoming Membrane FoulingDocument typeConference PaperPublisherWater Environment FederationPrint publication date Oct, 2007ISSN1938-6478SICI1938-6478(20071001)2007:11L.6402;1-DOI10.2175/193864707787223853Volume / Issue2007 / 11Content sourceWEFTECFirst / last page(s)6402 - 6416Copyright2007Word count232Subject keywordsMBRFOULINGCALCIUMEPSPERMEABILITY
Kinetic and Equilibrium Deuterium Isotope Effects for C—H Bond Reductive Elimination and Oxidative Addition Reactions Involving the ansa‐Tungstenocene Methyl—Hydride Complex [Me<sub>2</sub>Si(C<sub>5</sub>Me<sub>4</sub>)<sub>2</sub>]W(Me)H (2005)

Abstract For Abstract see ChemInform Abstract in Full Text.
Detection of interactions between myogenic and TGF mechanisms using nonlinear analysis (1994)

Previous studies using linear techniques have provided valuable insights into the dynamic characteristics of whole kidney autoregulation and have led to the general conclusion that the myogenic mechanism and tubuloglomerular feedback (TGF) are highly nonlinear control mechanisms. To explore further the dynamic nature of these nonlinear autoregulatory mechanisms, we introduce the technique of nonlinear modeling using Volterra-Wiener kernels. In the past several years, use of Volterra-Wiener kernels for nonlinear approximation has been most notably applied to neurophysiology. Recent advances in algorithms for computation of the kernels have made this technique more attractive for the study of the dynamics of nonlinear physiological systems, such as the system mediating renal autoregulation. In this study, the general theory and requirements for using this technique are discussed. The feasibility of using the technique on whole kidney pressure and flow data is examined, and a basis for using the Volterra-Wiener kernels to detect interactions between physiological control mechanisms is established. As a result of this method, we have identified the presence of interactions between the oscillating components of the myogenic and the TGF mechanisms at the level of the whole kidney blood flow in normotensive rats. An interaction between these oscillatory components had previously been demonstrated only at the single-nephron level.
Local and Global Order in Dense Packings of Semi-flexible Polymers of Hard Spheres (2023)

The local and global order in dense packings of linear, semi-flexible polymers of tangent hard spheres are studied by employing extensive Monte Carlo simulations at increasing volume fractions. Chain stiffness is controlled by a tunable harmonic potential for the bending angle whose intensity dictates the rigidity of the polymer backbone as a function of the bending constant and equilibrium angle. The studied angles range from acute to obtuse ones, reaching the limit of rod-like polymers. We analyze how packing density and chain stiffness affect the ability of chains to self-organize at the local and global levels. The former corresponds to crystallinity as quantified by the Characteristic Crystallographic Element (CCE) norm descriptor, while the latter is computed through the scalar orientational order parameter. In all cases, we identify the critical volume fraction for the phase transition and gauge the established crystal morphologies, developing a complete phase diagram as a function of packing density and equilibrium bending angle. A plethora of structures is obtained, ranging from random hexagonal closed packed morphologies of mixed character and almost perfect face centered cubic (FCC) and hexagonal close-packed (HCP) crystals at the level of monomers, to nematic mesophases, with prolate and oblate mesogens at the level of chains. For rod-like chains, hysteresis is observed between the establishment of long-range nematic order and crystallization, while for right-angle chains both transitions are synchronized. A comparison is also provided against the analogous packings of monomeric and fully flexible chains of hard spheres.
Direct Amplification and Cloning of Up to 5-kb Lentivirus Genomes from Serum (1996)

To produce large cDNA strands from biological samples containing limited numbers of template molecules, it may be necessary to minimize both nonspecific primer attachment in first-strand synthesis and secondary structure in RNA molecules. Failure to do so could result in the accumulation of shortened cDNA strands and therefore may reduce the yield of large cDNA molecules, sometimes below detection level. We show that 5.0-kb cDNA fragments can be generated from simian immunodeficiency virus RNA in a specific reverse transcription (RT)-PCR by increasing the stringency of the primer-annealing conditions, followed by the elimination of excess free primer. Since this method utilizes a relatively long primer in the first-strand cDNA synthesis, it is possible to heat-denature the nonspecific RNA/primer complexes and RNA secondary structure without dissociating the primer from the specific template. In contrast to classic RT assays, in which an excess of primer is annealed to denatured RNA just prior to and during reverse transcription at relative low temperatures (37 degrees-42 degrees C), this method eliminates false priming. To optimize the yield and fidelity of full-length cDNA molecules, two PCR amplifications are first performed using both Taq and Pfu polymerase, followed by Pfu alone in the second amplification.
HTS insert coils for ultra high field NMR spectroscopy (1997)

In this paper we describe the design, fabrication and test of a model high field insert magnet utilizing react and wind BSCCO-2212 surface coated (SC) tape conductors. An added central field of 1.2 T and 1.08 T was achieved at 4.2 K over a technologically useful 50 mm clear bore in applied background fields of 0 and 5.5 T respectively, In addition, we report the results of high field measurements to 17.5 T made on a double pancake coil module fabricated using react and wind BSCCO-2212 powder-in-tube (PIT) tape. The insert magnet and pancake coil modules are part of a continuing effort to demonstrate the application of HTS conductors for the generation of the high magnetic fields required for NMR systems operating at the 1.0 GHz level.
Structure of the Heliotail from Interstellar Boundary Explorer Observations: Implications for the 11-year Solar Cycle and Pickup Ions in the Heliosheath (2017)

Abstract Interstellar Boundary Explorer ( IBEX ) measurements of energetic neutral atoms (ENAs) from the heliotail show a multi-lobe structure of ENA fluxes as a function of energy between ∼0.71 and 4.29 keV. Below ∼2 keV, there is a single structure of enhanced ENA fluxes centered near the downwind direction. Above ∼2 keV, this structure separates into two lobes, one north and one south of the solar equatorial plane. ENA flux from these two lobes can be interpreted as originating from the fast solar wind (SW) propagating through the inner heliosheath (IHS). Alternatively, a recently published model of the heliosphere suggests that the heliotail may split into a “croissant-like” shape, and that such a geometry could be responsible for the heliotail ENA feature. Here we present results from a time-dependent simulation of the heliosphere that produces a comet-like heliotail, and show that the 11-year solar cycle leads to the formation of ENA lobes with properties remarkably similar to those observed by IBEX . The ENA energy at which the north and south lobes appear suggests that the pickup ion (PUI) temperature in the slow SW of the IHS is ∼10 7 K. Moreover, we demonstrate that the extinction of PUIs by charge-exchange is an essential process required to create the observed global ENA structure. While the shape and locations of the ENA lobes as a function of energy are well reproduced by PUIs that cross the termination shock, the results appear to be sensitive to the form of the distribution of PUIs injected in the IHS.
Improved reactivity and derivatization of cellulose after pre-hydrolysis with commercial enzymes (2018)

Reactivity is an important parameter when considering the chemical modification or dissolution of cellulose. Different pretreatment methods affect cellulose reactivity by decreasing its degree of polymerization (DP) and crystallinity. In this study, the molar mass of cellulose was decreased via enzymatic pretreatment. Three commercial endoglucanase-rich products were tested. The target was to reduce the viscosity of the pulp to below 200 mL/g and, thus, increase the reactivity of the cellulose. For comparison, cellulose was also pretreated with ozone, and the effects of each pretreatment method on crystallinity and monosaccharide composition of the resulting pulps were investigated. Both enzymatically treated and ozone-treated pulps were esterified using homogeneous and heterogeneous methods, and the degrees of substitution for these treated pulps were much higher than the esters when the untreated pulp was used. Cellulose esters from the pretreated pulps formed films with good mechanical properties by solvent casting.