gebhart/patrepeval huggingface dataset:
The Branch Point Enzyme of the Mevalonate Pathway for Protein Prenylation Is Overexpressed in the <i>ob</i>/<i>ob</i> Mouse and Induced by Adipogenesis (2000)

We have recently reported that skeletal muscle of the ob/ob mouse, an animal model of genetic obesity with extreme insulin resistance, exhibits alterations in the expression of multiple genes. Analysis and cloning of a full-length cDNA of one of the overexpressed mRNAs revealed a 300-amino-acid protein that could be identified as the mouse geranylgeranyl diphosphate synthase (GGPP synthase) based on its homology to proteins cloned from yeast and fungus. GGPP synthase catalyzes the synthesis of all-trans-geranylgeranyl diphosphate (GGPP), an isoprenoid used for protein isoprenylation in animal cells, and is a branch point enzyme in the mevalonic acid pathway. Three mRNAs for GGPP synthase of 4.3, 3.2, and 1.7 kb were detected in Northern blot analysis. Western blot analysis of tissue homogenates using specific antipeptide antibodies revealed a single band of 34.8 kDa. Expression level of this protein in different tissues correlated with expression of the 4.3- and 3.2-kb mRNAs. GGPP synthase mRNA expression was increased 5- to 20-fold in skeletal muscle, liver, and fat of ob/ob mice by Northern blot analysis. Western blot analysis also showed a twofold overexpression of the protein in muscle and fat but not in liver, where the dominant isoform is encoded by the 1.7-kb mRNA. Differentiation of 3T3-L1 fibroblasts into adipocytes induced GGPP synthase expression more than 20-fold. Using the immunoprecipitated protein, we found that mammalian GGPP synthase synthesizes not only GGPP but also its metabolic precursor farnesyl diphosphate. Thus, the expression of GGPP synthase is regulated in multiple tissues in obesity and is induced during adipocyte differentiation. Altered regulation in the synthesis of isoprenoids for protein prenylation in obesity might be a factor determining the ability of the cells to respond to hormonal stimulation requiring both Ras-related small GTPases and trimeric G protein-coupled receptors.
Protected gates for superconducting qubits (2013)

We analyze the accuracy of quantum phase gates acting on ``0-$\ensuremath{\pi}$ qubits'' in superconducting circuits, where the gates are protected against thermal and Hamiltonian noise by continuous-variable quantum error-correcting codes. The gates are executed by turning on and off a tunable Josephson coupling between an $LC$ oscillator and a qubit or pair of qubits; assuming perfect qubits, we show that the gate errors are exponentially small when the oscillator's impedance $\sqrt{L/C}$ is large compared to $\ensuremath{\hbar}/4{e}^{2}\ensuremath{\approx}1\phantom{\rule{4pt}{0ex}}\mathrm{k}\ensuremath{\Omega}$. The protected gates are not computationally universal by themselves, but a scheme for universal fault-tolerant quantum computation can be constructed by combining them with unprotected noisy operations. We validate our analytic arguments with numerical simulations.
Phase control of reflectarray patches using liquid crystal substrate (2006)

In this proof of concept study we employ numerical and measured results at X- band to demonstrate that the dielectric anisotropy of nematic state liquid crystal can be exploited to produce electronically controlled phase shifters for printed reflectarray antennas. Phase agility is realized by inserting a layer of liquid crystal in the region between the resonant patch array and the conductive ground plane. Applying a low frequency biasing voltage produces a small change in the permittivity of the substrate and this is shown to create a large shift in the phase of the reflected signal. Ansoft HFSS version 10.0 is employed to study the scattering behaviour of the array elements in the range 9-11 GHz using the dielectric properties of commercially available liquid crystals. The simulated phase range, bandwidth and reflection loss are shown to be in close agreement with measurements that were obtained from a waveguide simulator. The most significant impact of this new active control strategy is in the mm and sub-mm wave band and therefore a technique is proposed for characterising the electrical performance of liquid crystals at these frequencies. This paper summarises the progress that has been made in the first stage of a collaborative academic/industrial project to investigate the feasibility of creating high frequency beam scanning reflectarray antennas for future space science instruments.
Tolerance Induced by Thymic Epithelial Grafts in Birds (1987)

Grafts of the anterior limb bud introduced at embryonic day 4 between histoincompatible chick embryos were subject to chronic, mild rejection beginning from several weeks to several months after birth. In contrast, quail wing buds similarly grafted into chickens started to be rejected at the first or second week after birth and finally autoamputated. Embryonic thymus epithelium from donor quail (before it had been colonized by hemopoietic cells) was grafted into chicks. A chimeric thymic epithelial stroma was generated in which the lymphocytes of the chick acquired the capacity to recognize the grafted limb as self either permanently or for a protracted period of time. In such thymic chimeras the grafted wings were not rejected.
The metabolism of host RNAs in cells infected by an adenovirus E4 mutant (1991)

Mutants of adenovirus type 5 (Ad5) that lack early region 4 (E4) are defective in the expression of viral late genes. E4 mutants exhibit dramatically reduced levels of both cytoplasmic and nuclear viral late RNAs compared to wild-type virus, due principally to reduced stability of unprocessed viral late RNA in the nucleus of mutant-infected cells. To determine whether E4 products also affect the metabolism of host RNAs in infected cells, steady-state levels of beta-actin RNA and triose phosphate isomerase (TPI) RNA were measured in the cytoplasms and nuclei of HeLa cells infected by either wild-type Ad5 or the E4 deletion mutant H5dl1004, and were compared to levels in uninfected HeLa cells. S1 nuclease analyses revealed only slight reductions in beta-actin mRNA levels in the cytoplasm and in levels of spliced and unspliced beta-actin RNA in the nucleus of cells infected by either Ad5 or H5dl1004. RNase protection analyses showed that cytoplasmic TPI RNA levels were not affected by infection of HeLa cells with either Ad5 or H5dl1004. Steady-state levels of nuclear TPI RNA, both spliced and unspliced, were slightly reduced in cells infected by wild-type virus but not in HeLa cells infected by H5dl1004. These results indicate that the reduced stability of RNA in HeLa cells infected by E4 mutants is a virus-specific phenotype which does not extend to host cell RNAs.
Photochemical dry etching of GaAs (1984)

GaAs exhibits greatly enhanced reactivity with gas-phase reactive Cl species when the surface is irradiated with low intensity laser light having a frequency which can excite above the band gap of GaAs. This laser-induced reactivity is shown to be photochemical rather than thermal in origin. This is the first reported observation of a purely photochemical dry etching process for a III-V semiconductor material.
CD8+ T Cell-Mediated Suppression of Autoimmunity in a Murine Lupus Model of Peptide-Induced Immune Tolerance Depends on Foxp3 Expression (2007)

Systemic lupus erythematosus is an autoimmune disease caused by autoantibodies, including IgG anti-DNA. New Zealand Black/New Zealand White F(1) female mice, a model of spontaneous polygenic systemic lupus erythematosus, tolerized with an artificial peptide (pConsensus) based on anti-DNA IgG sequences containing MHC class I and class II T cell determinants, develop regulatory CD4+CD25+ T cells and CD8+ inhibitory T cells (CD8+ Ti), both of which suppress autoantibody production. CD8+ Ti inhibit primarily via secretion of TGF-beta. In the present study, we show that the inhibitory function of CD8+ T cells from tolerized mice is sustained for up to 8 wk and at all times depends on expression of Foxp3. Both CD28-positive and CD28-negative CD8+ T cells contain inhibitory cells, but the expression of mRNA for Foxp3 and for TGF-beta is higher and lasts longer in the CD28- subset. In vitro addition of TGF-beta (in the presence of IL-2) induces Foxp3 expression in a dose-response manner. Gene inhibition or blockade with small interfering RNA of Foxp3 abrogates the ability of the CD8+ Ti to inhibit anti-DNA production and the proliferation of CD4+ Th cells. Moreover, a significant correlation between expression of Foxp3 and ability of CD8+ Ti to secrete TGF-beta is observed. Therefore, CD8+ Ti in this system of tolerance are similar to CD4+CD25+ regulatory T cells in their dependence on expression of Foxp3, and there may be a bidirectional Foxp3/TGF-beta autocrine loop that determines the ability of the CD8+ T cells to control autoimmunity.
Improving the light-harvesting of second generation solar cells with photochemical upconversion (2012)

Photovoltaics (PV) offer a solution for the development of sustainable energy sources, relying on the sheer abundance of sunlight: More sunlight falls on the Earth’s surface in one hour than is required by its inhabitants in a year. However, it is imperative to manage the wide distribution of photon energies available in order to generate more cost efficient PV devices because single threshold PV devices are fundamentally limited to a maximum conversion efficiency, the Shockley-Queisser (SQ) limit. Recent progress has enabled the production of c-Si cells with efficiencies as high as 25%,<sup>1</sup> close to the limiting efficiency of ∼30%. But these cells are rather expensive, and ultimately the cost of energy is determined by the ratio of system cost and efficiency of the PV device. A strategy to radically decrease this ratio is to circumvent the SQ limit in cheaper, second generation PV devices. One promising approach is the use of hydrogenated amorphous silicon (a-Si:H), where film thicknesses on the order of several 100nm are sufficient. Unfortunately, the optical threshold of a-Si:H is rather high (1.7-1.8 eV) and the material suffers from light-induced degradation. Thinner absorber layers in a-Si:H devices are generally more stable than thicker films due to the better charge carrier extraction, but at the expense of reduced conversion efficiencies, especially in the red part of the solar spectrum (absorption losses). Hence for higher bandgap materials, which includes a-Si as well as organic and dye-sensitized cells, the major loss mechanism is the inability to harvest low energy photons.
An Introduction to Hidden Markov Models (2007)

This unit introduces the concept of hidden Markov models in computational biology. It describes them using simple biological examples, requiring as little mathematical knowledge as possible. The unit also presents a brief history of hidden Markov models and an overview of their current applications before concluding with a discussion of their limitations.
Towards non-toxic solvents for membrane preparation: a review (2014)

Solvents are used in every chemical process and affect its overall safety, environmental, and economic impact. Membrane processes have attracted increasing interest as sustainable alternatives to traditional technologies, being characterized by reduced energy consumption and use of chemicals. However, the most important membrane preparation techniques are often based on the use of toxic solvents, which reduces the benefit to the environment. Due to the influence of solvent properties such as viscosity, dielectric constant, polarity, and boiling point on the final features and the indispensable prerequisite of dissolving the selected polymer (at room or high temperature, depending on the technique), one of the most difficult but most interesting challenges for membrane scientists is replacing these solvents, such as N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMA), N-methyl-2-pyrrolidone (NMP), and tetrahydrofuran (THF), with safer alternatives. In this review, the most relevant steps towards the use of non-toxic solvents in membrane preparation are reported, focusing particular attention on the non-solvent induced and temperature induced phase separation (NIPS and TIPS) techniques. Supercritical CO2 (ScCO2) and ionic liquids (ILs) are promising examples of benign solvents, and their use in membrane preparation will also be described. The total replacement of toxic diluents with greener alternatives still remains at the beginning stages. However, in several cases, membranes prepared using less/non-toxic solvents achieved performance comparable to those produced with classical toxic solvents. This review offers valid support for membrane scientists who wish to reduce the environmental impact of solvent use and increase membrane processes sustainability.
Power conservation strategy for mobile computers using load sharing (1998)

Power management is an important aspect of mobile computing. Previous works on power conservation have concentrated on the hardware approach. In this paper, we propose a different approach of power conservation strategy for mobile computers which is based on the concept of load sharing. User jobs are transferred from a mobile host to a fixed host to reduce power consumption by the CPU. Simulation results show that under suitable conditions, transferring job can extend battery lifetime by up to 20%. Transferring jobs to a fixed host does not only extend battery lifetime but also gives users access to faster machines, hence improving job response time.
Some novel elements for delta-modulated signal processing (1981)

New and interesting multipliers are proposed to use for the direct-multiplication of delta-modulated signals by constants. In addition to a non-recursive form, three recursive-form delta multipliers are given. The recursive multipliers are suitable for multiplication by periodic numbers or by non-periodic numbers which can be approached by periodic ones. A significantly smaller number of delta adders is needed for the realization of recursive delta multipliers, than for the non-recursive ones. In addition, an interconnecting method is suggested, if the outputs of the multipliers are to be added. With the method a significant reduction of the scaling-down is achieved as well as a reduction of the total number of the necessary adders for the realization of the multipliers. The combination of interconnecting multipliers and delta doubters gives very good results for the realization of digital filters.
Transporting Mobility Control Agents to Thief Zones (1994)

Abstract This paper will present experimental results that demonstrate a novel plugging mechanism for improving the areal sweep efficiency for EOR solvents such as carbon dioxide or light hydrocarbons, or mixtures of the two. Early gas breakthrough due to thief zones or gas override is the single most significant factor affecting the sweep efficiency of miscible gas processes. WAG is routinely used and foams are being investigated for diverting gas to upswept zones. Both approaches require injecting an aqueous phase which leads to water blocking and slows gas injection, thus delaying oil recovery. Additionally, foams have a short life, are limited to near-wellbore applications due to surfactant during every cycle of surfactant injection. The optimal solution calls for a deep penetrating plugging agent carried in the solvent phase for accurate and economical delivery to thief or override zones. Additionally, the process should be simple, safe in the wellbore region, robust, and easily activated. It has already been demonstrated that cosolvents like toluene will successfully solubilize polydimethylsiloxane-type polymers in CO2, and that polymer solubility decreases with increasing temperature and decreasing pressure. Consequently, it is feasible to define a polymer + cosolvent combination that is homogeneous at the lower temperature of the injector, but will destabilize as the injected slug moves through the formation and is subjected to higher temperatures and lower pressures. Figure 1 represents the solubility phase boundary for a 600,000 cst polydimethylsiloxane polymer in CO2- toluene mixtures as a function of temperature, pressure, and two cosolvent concentrations. For either cosolvent concentration, a single phase condition exists for temperature and pressure combinations that would place the system above the phase boundary line, with polymer dropping out of solution once the system conditions drop below the line. Consider the specific case of a CO2 flood in a reservoir at 180°F. and 4,000 psia, where the injector is at 130 ° F., and early gas breakthrough has taken place. The working of this process would require injecting a CO2 phase enriched with 7.1 vol.% toluene and 600,000 cst polymer as a one phase system at the injector. As this mixture moves through the reservoir and increases in temperature, the stability decreases, and once the temperature at fixed pressure crosses the phase boundary line, the polymer phase separates out to plug the zone.
MOF–Graphite Oxide Composites: Combining the Uniqueness of Graphene Layers and Metal–Organic Frameworks (2009)

Nanocomposites containing graphite oxide (GO) and metal–organic frameworks (MOFs) are prepared. They have a well-defined structure, in which graphene layers from GO alternate with layers of MOF via linkages between epoxy groups from GO and zinc oxide from the MOF (see image). The enhanced porosity and dispersive forces of the composites compared to the precursors provide views for applications in gas adsorption.
236. The chemistry of the pyrrocolines. Part I. 2-Methyl- and 2-phenyl-pyrrocoline (1946)

E. T. Borrows, D. O. Holland and J. Kenyon, J. Chem. Soc., 1946, 1069 DOI: 10.1039/JR9460001069
Isotope effects on the optical spectra of semiconductors (2005)

Since the end of the cold war, macroscopic amounts of separated stable isotopes of most elements have been available ``off the shelf'' at affordable prices. Using these materials, single crystals of many semiconductors have been grown and the dependence of their physical properties on isotopic composition has been investigated. The most conspicuous effects observed have to do with the dependence of phonon frequencies and linewidths on isotopic composition. These affect the electronic properties of solids through the mechanism of electron-phonon interaction, in particular, in the corresponding optical excitation spectra and energy gaps. This review contains a brief introduction to the history, availability, and characterization of stable isotopes, including their many applications in science and technology. It is followed by a concise discussion of the effects of isotopic composition on the vibrational spectra, including the influence of average isotopic masses and isotopic disorder on the phonons. The final sections deal with the effects of electron-phonon interaction on energy gaps, the concomitant effects on the luminescence spectra of free and bound excitons, with particular emphasis on silicon, and the effects of isotopic composition of the host material on the optical transitions between the bound states of hydrogenic impurities.
Six-year follow-up of glutaraldehyde-preserved heterografts. With particular reference to the treatment of congenital valve malformations. (1974)

Glutaraldehyde preservation for the preparation of heterograft valves, a process which we introduced in 1968, has been responsible for considerable improvements in long-term clinical results. We have based this report on results obtained in the first 104 patients operated upon between March, 1968, and March, 1973. Eighty-two patients had acquired valvular disease, and the other 22 had congenital valvular malformations, including 7 with Ebstein's anomaly and 8 with absence of the pulmonary valve. The hospital mortality rate was 18 per cent in the group with congenital disease and 11 per cent in the group with acquired valvular disease. We noted that 6.5 per cent of the deaths occurred in single valve replacement and 16 per cent in multiple valve replacement. Three late deaths were valve related. There were 2 cases of acute bacterial endocarditis postoperatively and 7 cases of valve dysfunction 1, 4, 4.5, and 5 years after the operation. Histologic examination showed no evidence of immunologic reaction. Cusp perforations developed as a result of localized areas of collagen degeneration. In 67 patients, valve function remains excellent. Hemodynamic data are available in 11 patients. The various factors affecting valve preparation and durability are discussed in this report, and the present role of the glutaraldehyde-preserved heterograft valve in cardiac valve replacement is evaluated.
Viruses, microRNAs, and Host Interactions (2010)

One of the most significant recent advances in biomedical research has been the discovery of the approximately 22-nt-long class of noncoding RNAs designated microRNAs (miRNAs). These regulatory RNAs provide a unique level of posttranscriptional gene regulation that modulates a range of fundamental cellular processes. Several viruses, especially herpesviruses, also encode miRNAs, and over 200 viral miRNAs have now been identified. Current evidence indicates that viruses use these miRNAs to manipulate both cellular and viral gene expression. Furthermore, viral infection can exert a profound impact on the cellular miRNA expression profile, and several RNA viruses have been reported to interact directly with cellular miRNAs and/or to use these miRNAs to augment their replication potential. Here we discuss our current knowledge of viral miRNAs and virally influenced cellular miRNAs and their relationship to viral infection.
Investigation of Guanidine Carbonate-Based Slurries for Chemical Mechanical Polishing of Ru/TiN Barrier Films with Minimal Corrosion (2014)

This work describes the response of Ru/TiN barrier films to solutions of H2O2, guanidine carbonate (GC) and other additives in terms of open circuit potential measurements and potentiodynamic polarization data. It was found that an aqueous solution containing 1 wt% H2O2, 0.25 wt% GC and 5 mM BTA is effective in maintaining a low corrosion potential gap of Ru and Cu at ∼15 mV at pH 9. The slurry prepared by adding 5 wt% silica to this mixture yields a Ru removal rate (RR) of 10 nm/min and a Cu RR of 12 nm/min at 2 psi polishing pressure. The effect of carbonate and guanidinium ions as well as BTA on the corrosion behavior of Ru and Cu is discussed. Dodecyl-benzene-sulfonic acid (DBSA) was also found to be an effective corrosion inhibitor of Ru in the presence of H2O2 and GC based solutions at pH 9 with a good post-polished surface finish but reduced the Ru RRs to ∼ 2 nm/min.