gebhart/patrepeval huggingface dataset:
Differential Roles of Sall4 Isoforms in Embryonic Stem Cell Pluripotency (2010)

Murine embryonic stem (ES) cells are defined by continuous self-renewal and pluripotency. A diverse repertoire of protein isoforms arising from alternative splicing is expressed in ES cells without defined biological roles. Sall4, a transcription factor essential for pluripotency, exists as two isoforms (Sall4a and Sall4b). Both isoforms can form homodimers and a heterodimer with each other, and each can interact with Nanog. By genomewide location analysis, we determined that Sall4a and Sall4b have overlapping, but not identical binding sites within the ES cell genome. In addition, Sall4b, but not Sall4a, binds preferentially to highly expressed loci in ES cells. Sall4a and Sall4b binding sites are distinguished by both epigenetic marks at target loci and their clustering with binding sites of other pluripotency factors. When ES cells expressing a single isoform of Sall4 are generated, Sall4b alone could maintain the pluripotent state, although it could not completely suppress all differentiation markers. Sall4a and Sall4b collaborate in maintenance of the pluripotent state but play distinct roles. Our work is novel in establishing such isoform-specific differences in ES cells.
Functional expression and characterization of the Epstein-Barr virus DNA polymerase catalytic subunit (1993)

A recombinant baculovirus containing the complete sequence for the Epstein-Barr virus (EBV) DNA polymerase catalytic subunit, BALF5 gene product, under the control of the baculovirus polyhedrin promoter was constructed. Insect cells infected with the recombinant virus produced a protein of 110 kDa, recognized by anti-BALF5 protein-specific polyclonal antibody. The expressed EBV DNA polymerase catalytic polypeptide was purified from the cytosolic fraction of the recombinant virus-infected insect cells. The purified protein exhibited both DNA polymerase and 3'-to-5' exonuclease activities, which were neutralized by the anti-BALF5 protein-specific antibody. These results indicate that the 3'-to-5' exonuclease activity associated with the EBV DNA polymerase (T. Tsurumi, Virology 182:376-381, 1991) is an inherent feature of the polymerase catalytic polypeptide. The DNA polymerase and the exonuclease activities of the EBV DNA polymerase catalytic subunit were sensitive to ammonium sulfate in contrast to those of the polymerase complex purified from EBV-producing lymphoblastoid cells, which were stimulated by salt. Furthermore, the template-primer preference for the polymerase catalytic subunit was different from that for the polymerase complex. These observations strongly suggest that the presence of EBV DNA polymerase accessory protein, BMRF1 gene product, does influence the enzymatic properties of EBV DNA polymerase catalytic subunit.
Further studies on LiF-overcoated aluminum mirrors with highest reflectance in the vacuum ultraviolet. (1968)

LiF overcoated Al mirror preparation with highest reflectance in vacuum UV, noting vacuum deposition methods
Effect of degree of deacetylation of chitosan on the kinetics of ultrasonic degradation of chitosan (2003)

Abstract The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003
IMMUNOSUPPRESSIVE-ASSOCIATED LEUKOENCEPHALOPATHY IN ORGAN TRANSPLANT RECIPIENTS (2000)

Immunosuppressive-associated leukoencephalopathy is a significant complication of cyclosporine (CsA) or tacrolimus therapy. However, the precise time of onset, role of putative risk factors, differences, if any, in presentation in various types of organ transplantation and outcome of this entity, remain poorly defined. Fifty cases of immunosuppressive-associated leukoencephalopathy reported in the literature in organ transplant recipients, were reviewed. Of 50 cases, 31 occurred in liver, 8 in renal, 6 in lung, and 5 in heart transplant recipients. Median time to onset was 28 days (range 3-1512 days); 82% occurred within 90 days of transplantation. Lesions tended to occur earlier in the liver transplant recipients, compared with other organ transplant recipients (median 9 vs. 29 days, P=.19). Seizures 74%, altered mental status 50%, and visual abnormalities 28% were the most frequently presenting features. Ten percent of the patients had fever with no documented source of infection. Systemic hypertension (P=.001), and lesions in the presence of therapeutic drug levels (P=.11) were more likely to occur with CsA than tacrolimus. Neuroimaging and clinical abnormalities were reversible on cessation or reduction of CsA or tacrolimus in all but two cases. Resolution of neurologic signs/symptoms occurred a median of 4 days and neuroimaging abnormalities in a median of 20 days on reduction/cessation of the drug. Immunosuppressive-associated leukoencephalopathy is a unique entity that can usually be diagnosed on the basis of its distinctive time of onset, and clinical and neuroimaging characteristics, and it is potentially reversible if promptly diagnosed. Despite identical clinical presentation of this syndrome in the recipients of CsA and tacrolimus, above noted variations in risk factors suggest that a difference in pathophysiologic mechanism may exist.
Modulation of Na<sup>+</sup>transport and epithelial sodium channel expression by protein kinase C in rat alveolar epithelial cells (2005)

Although the amiloride-sensitive epithelial sodium channel (ENaC) plays an important role in the modulation of alveolar liquid clearance, the precise mechanism of its regulation in alveolar epithelial cells is still under investigation. Protein kinase C (PKC) has been shown to alter ENaC expression and activity in renal epithelial cells, but much less is known about its role in alveolar epithelial cells. The objective of this study was to determine whether PKC activation modulates ENaC expression and transepithelial Na+ transport in cultured rat alveolar epithelial cells. Alveolar type II cells were isolated and cultured for 3 to 4 d before they were stimulated with phorbol 12-myristate 13-acetate (PMA 100 nmol/L) for 4 to 24 h. PMA treatment significantly decreased alpha, beta, and gammaENaC expression in a time-dependent manner, whereas an inactive form of phorbol ester had no apparent effect. This inhibitory action was seen with only 5-min exposure to PMA, which suggested that PKC activation was very important for the reduction of alphaENaC expression. The PKC inhibitors bisindolylmaleimide at 2 micromol/L and Gö6976 at 2 micromol/L diminished the PMA-induced suppression of alphaENaC expression, while rottlerin at 1 micromol/L had no effect. PMA elicited a decrease in total and amiloride-sensitive current across alveolar epithelial cell monolayers. This decline in amiloride-sensitive current was not blocked by PKC inhibitors except for a partial inhibition with bisindolylmaleimide. PMA induced a decrease in rubidium uptake, indicating potential Na+-K+-ATPase inhibition. However, since ouabain-sensitive current in apically permeabilized epithelial cells was similar in PMA-treated and control cells, the inhibition was most probably related to reduced Na+ entry at the apical surface of the cells. We conclude that PKC activation modulates ENaC expression and probably ENaC activity in alveolar epithelial cells. Ca2+-dependent PKC is potentially involved in this response.
Parallel query processing in distributed object database systems by query packets (2002)

In this paper, we propose a new approach for parallel query processing in distributed object database systems. An object query is disassembled into a set of query packets which can be processed independently and in parallel at each site. Three alternative query packet processing strategies are discussed. Comparing with the conventional OID-join approach, the query packet approach dramatically reduces the response time and gives better work load balancing.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Renal Magnetic Resonance Angiography in the Preoperative Detection of Supernumerary Renal Arteries in Potential Kidney Donors (1993)

The high error rate (60%) suggests that two-dimensional PC MRA, as implemented, should not be used in the preoperative evaluation of potential renal donors.
Nanomechanical Actuation of a Silicon Cantilever Using an Azo Dye, Self-Assembled Monolayer (2013)

The emerging fields of nanomotors and optomechanics are based on the harnessing of light to generate force. However, our ability to detect small surface stresses is limited by temperature drift, environmental noise, and low-frequency flicker electronic noise. To address these limitations, we functionalized microfabricated silicon cantilevers with an azo dye, silane-based self-assembled monolayer and modulated the surface stress by exciting the optical switch with a 405-nm laser. Atomic force microscopy, contact angle analysis, ellipsometry, and X-ray photoelectron spectroscopy verified successful assembly of molecules on the cantilever. Ultraviolet and visible spectra demonstrate optical switching of the synthesized molecule in solution. By turning the laser on and off at a specific rate (e.g., 1 Hz), the cantilever deflection can be measured via Fourier techniques, thus separating the signal of interest from the noise. This technique empowers the design of highly sensitive surface stress measurements.
PEM fuel cell system power control based on a feedback-linearization approach (2012)

Polymer electrolyte membrane (PEM) fuel cell systems are highly efficient energy converters. Besides electrical power, low oxygen concentration cathode exhaust gas, water and heat are the byproducts if fed with pure hydrogen gas. So, this technology has become very attractive for the use on aircraft where it is investigated as replacement for the auxiliary power unit that is currently used for electrical power generation. Hence, controlling the fuel cell system for electrical power is a central topic. The electrical power output, however, is nonlinearly dependent on stack temperature, gas pressure, membrane humidity and stack current that is being drawn. This study deals with the controls of electrical power of an air and hydrogen fed self-powered fuel cell system. For controller design the nonlinear polarization curve is approximated by a linear current-voltage-characteristic. Based on a feedback-linearization approach a nonlinear control law for fuel cell system power is presented and implemented in a nonlinear fuel cell system simulation model. Even though the polarization curve is a linear approximation, the nonlinear control law leads to a fast response and zero steady state error.
Optimization of combinational and sequential logic circuits for low power using precomputation (2002)

Precomputation is a recently proposed logic optimization technique which selectively disables the inputs of a sequential logic circuit, thereby reducing switching activity and power dissipation, without changing logic functionality. In this paper, we present new precomputation architectures for both combinational and sequential logic and describe new precomputation-based logic synthesis methods that optimize logic circuits for low power. We present a general precomputation architecture for sequential logic circuits and show that it is significantly more powerful than the architectures previously treated in the literature. In this architecture, output values required in a particular clock cycle are selectively precomputed one clock cycle earlier, and the original logic circuit is "turned off" in the succeeding clock cycle. The very power of this architecture makes the synthesis of precomputation logic a challenging problem and we present a method to automatically synthesize precomputation logic for this architecture. We introduce a powerful precomputation architecture for combinational logic circuits that uses transmission gates or transparent latches to disable parts of the logic. Unlike in the sequential circuit architecture, precomputation occurs in an early portion of a clock cycle, and parts of the combinational logic circuit are "turned off" in a later portion of the same clock cycle. Further we are not restricted to perform precomputation on the primary inputs. Preliminary results obtained using the described methods are presented. Up to 66 percent reductions in switching activity and power dissipation are possible using the proposed architectures. For many examples, the proposed architectures result in significantly less power dissipation than previously developed methods.
Stretchable and Flexible High-Strain Sensors Made Using Carbon Nanotubes and Graphite Films on Natural Rubber (2014)

Conventional metallic strain sensors are flexible, but they can sustain maximum strains of only ~5%, so there is a need for sensors that can bear high strains for multifunctional applications. In this study, we report stretchable and flexible high-strain sensors that consist of entangled and randomly distributed multiwall carbon nanotubes or graphite flakes on a natural rubber substrate. Carbon nanotubes/graphite flakes were sandwiched in natural rubber to produce these high-strain sensors. Using field emission scanning electron microscopy, the morphology of the films for both the carbon nanotube and graphite sensors were assessed under different strain conditions (0% and 400% strain). As the strain was increased, the films fractured, resulting in an increase in the electrical resistance of the sensor; this change was reversible. Strains of up to 246% (graphite sensor) and 620% (carbon nanotube sensor) were measured; these values are respectively ~50 and ~120 times greater than those of conventional metallic strain sensors.
Thioxanthone–carbazole as a visible light photoinitiator for free radical polymerization (2010)

Abstract A thioxanthone (TX) derivative with the additional carbazole chromophore, namely thioxanthone‐carbazole (TX‐C) was synthesized and characterized. The photophysical properties and its efficiency to polymerize methyl methacrylate both in the presence and absence of N , N ‐dimethylaniline (DMA) as coinitiator was investigated and compared with that of the commercially available TX. TX‐C was found to display better photophysical properties and in both cases initiate polymerization more efficiently. Detailed real‐time Fourier transform infrared studies revealed that high polymerization rates can be obtained when TX‐C in conjunction with DMA was used. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
Intron-Mediated Enhancement of Gene Expression Independent of Unique Intron Sequences and Splicing (2000)

Either of the first two introns of the Arabidopsis tryptophan pathway gene PAT1 elevates mRNA accumulation from a PAT1:beta-glucuronidase (GUS) fusion roughly 5-fold without affecting the rate of PAT1:GUS transcription. To further explore the mechanism of this intron-mediated enhancement of gene expression, we wanted to determine whether splicing or specific intron sequences were necessary. In-frame derivatives of PAT1 intron 1, whose splicing was prevented by a point mutation or large deletions, were able to increase mRNA accumulation from a PAT1:GUS fusion, demonstrating that splicing per se is not required. Furthermore, each of a series of introns containing overlapping deletions that together span PAT1 intron 1 increased PAT1:GUS mRNA accumulation as much as the full-length intron did, indicating that all intron sequences are individually dispensable for this phenomenon. These results eliminate the simple idea that this intron stimulates mRNA accumulation via a unique RNA-stabilizing sequence or through the completed act of splicing. However, they are consistent with a possible role for redundant intron sequence elements or an association of the pre-mRNA with the spliceosome.
On the pseudo-subthreshold characteristics of polycrystalline-silicon thin-film transistors with large grain size (1993)

A two-dimensional nonplanar device simulator for polycrystalline-silicon thin-film transistors (poly-Si TFTs) was developed, in which the influence of trapped charges and carrier scattering within the grain boundary region are incorporated into Poisson's equations and drift-diffusion current formulations, respectively. With this simulator, the I-V characteristics of poly-Si TFT devices can be characterized. TFTs in polycrystalline silicon were fabricated to test the simulator. Special attention was paid to the conduction mechanism in poly-Si TFTs with large grain size. A concept called the pseudo-subthreshold region is presented to explain the observed behavior. The key factors affecting the pseudosubthreshold slope were investigated and elucidated using the simulator.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Identification of <i>SSF1, CNS1,</i> and <i>HCH1</i> as multicopy suppressors of a <i>Saccharomyces cerevisiae</i> Hsp90 loss-of-function mutation (1999)

Hsp90 functions in a multicomponent chaperone system to promote the maturation and maintenance of a diverse, but specific, set of target proteins that play key roles in the regulation of cell growth and development. To identify additional components of the Hsp90 chaperone system and its targets, we searched for multicopy suppressors of various temperature-sensitive mutations in the yeast Hsp90 gene, HSP82. Three suppressors were isolated for one Hsp90 mutant (glutamate --> lysine at amino acid 381). Each exhibited a unique, allele-specific pattern of suppression with other Hsp90 mutants and had unique structural and biological properties. SSF1 is a member of an essential gene family and functions in the response to mating pheromones. CNS1 is an essential gene that encodes a component of the Hsp90 chaperone machinery. The role of HCH1 is unknown; its sequence has no strong homology to any protein of known function. SSF1 and CNS1 were weak suppressors, whereas HCH1 restored wild-type growth rates at all temperatures tested to cells expressing the E381K mutant. Overexpression of CNS1 or HCH1, but not SSF1, enhanced the maturation of a heterologous Hsp90 target protein, p60(v-src). These results suggest that like Cns1p, Hch1p is a general modulator of Hsp90 chaperone functions, whereas Ssf1p likely is either an Hsp90 target protein or functions in the same pathway as an Hsp90 target protein.
Cross-Linking and Degradation of Step-Growth Hydrogels Formed by Thiol–Ene Photoclick Chemistry (2012)

Thiol–ene photoclick hydrogels have been used for a variety of tissue engineering and controlled release applications. In this step-growth photopolymerization scheme, four-arm poly(ethylene glycol) norbornene (PEG4NB) was cross-linked with dithiol containing cross-linkers to form chemically cross-linked hydrogels. While the mechanism of thiol–ene gelation was well described in the literature, its network ideality and degradation behaviors are not well-characterized. Here, we compared the network cross-linking of thiol–ene hydrogels to Michael-type addition hydrogels and found thiol–ene hydrogels formed with faster gel points and higher degree of cross-linking. However, thiol–ene hydrogels still contained significant network nonideality, demonstrated by a high dependency of hydrogel swelling on macromer contents. In addition, the presence of ester bonds within the PEG-norbornene macromer rendered thiol–ene hydrogels hydrolytically degradable. Through validating model predictions with experimental results, we found that the hydrolytic degradation of thiol–ene hydrogels was not only governed by ester bond hydrolysis, but also affected by the degree of network cross-linking. In an attempt to manipulate network cross-linking and degradation of thiol–ene hydrogels, we incorporated peptide cross-linkers with different sequences and characterized the hydrolytic degradation of these PEG-peptide hydrogels. In addition, we incorporated a chymotrypsin-sensitive peptide as part of the cross-linkers to tune the mode of gel degradation from bulk degradation to surface erosion.
Immunization - Vaccine Adjuvant Delivery System and Strategies (2018)

Immunization plays a key role in maintaining human health and each year, saves millions of lives from lethal pathogens and other fatal diseases in the most economical way, thanks to the advanced development of model vaccines. Subunit vaccines are regarded as a safer product than the whole microbe based-conventional vaccines and can be entrapped in various nanocarriers to form a vaccine adjuvant-delivery system (VADS) able to further boost their immunostimulatory activity. In this book, six groups of authors introduce immunization advances in VADSs designed for infection prophylaxis and cancer immunotherapy, problems and their resolution in both human and poultry immunization, and also, the mathematical model for assay of the basic immunization problem (BIP) understood from a finance point of view.
Carbon and Graphene Quantum Dots for Optoelectronic and Energy Devices: A Review (2015)

As new members of carbon material family, carbon and graphene quantum dots (CDs, GQDs) have attracted tremendous attentions for their potentials for biological, optoelectronic, and energy related applications. Among these applications, bio‐imaging has been intensively studied, but optoelectronic and energy devices are rapidly rising. In this Feature Article, recent exciting progresses on CD‐ and GQD‐based optoelectronic and energy devices, such as light emitting diodes (LEDs), solar cells (SCs), photodetctors (PDs), photocatalysis, batteries, and supercapacitors are highlighted. The recent understanding on their microstructure and optical properties are briefly introduced in the first part. Some important progresses on optoelectronic and energy devices are then addressed as the main part of this Feature Article. Finally, a brief outlook is given, pointing out that CDs and GQDs could play more important roles in communication‐ and energy‐functional devices in the near future.