gebhart/patrepeval huggingface dataset:
Theoretical and Experimental Study on Ion-Pair Formation and Partitioning of Organic Salts in Octanol/Water and Dichloromethane/Water Systems (2000)

A good linear correlation (r = 0.945) of the octanol/water and dichloromethane/water log P‘ values has been found for quaternary amines with organic counterions. Monte-Carlo simulation based potential of mean force curves (PMF) for medium and large quaternary amine cations, and small and medium size anions show partially different characters in dichloromethane (DCM) solvent. The PMFs show, with one exception, both locally stable contact and solvent-separated ion-pair arrangements. The solvent-separated form is at least as stable as the contact ion-pair. Consideration of two water molecules at the interaction sites of the ionic heads remarkably lowers the activation free energy toward the formation of the contact ion arrangement. The quaternary substitution of the nitrogen prevents hydrogen bonding to the cation at its most positive site. Secondary acceptor sites can still be important, but at larger separations the water molecules always formed strong hydrogen bonds only at the −COO- and −SO3- anionic sites. Stability of the contact ion-pair is enhanced by a water-bridged hydrogen-bond network possible only at small ion separations in DCM. According to a suggested putative model for ion-pair partitioning between water and DCM, the anion enters the organic phase and drags some water molecules. The cation separated by about 8−10 Å follows the hydrated anion in the organic phase. A mixture of the contact and solvent separated ion-pairs in DCM is preferably formed if the free energy difference does not exceed 2 kcal/mol, and the activation free energy of the contact ion-pair formation is no more than about 3 kcal/mol, as calculated for some ion-pairs here.
Cyclin D3 coordinates the cell cycle during differentiation to regulate erythrocyte size and number (2012)

Genome-wide association studies (GWASs) have identified a genetic variant of moderate effect size at 6p21.1 associated with erythrocyte traits in humans. We show that this variant affects an erythroid-specific enhancer of CCND3 . A Ccnd3 knockout mouse phenocopies these erythroid phenotypes, with a dramatic increase in erythrocyte size and a concomitant decrease in erythrocyte number. By examining human and mouse primary erythroid cells, we demonstrate that the CCND3 gene product cyclin D3 regulates the number of cell divisions that erythroid precursors undergo during terminal differentiation, thereby controlling erythrocyte size and number. We illustrate how cell type-specific specialization can occur for general cell cycle components—a finding resulting from the biological follow-up of unbiased human genetic studies.
Renal Net Glucose Release In Vivo and Its Contribution to Blood Glucose in Rats (1978)

This study describes the contribution of de novo glucose synthesis by the kidney to blood glucose homeostasis in rats. The net glucose release by the kidney in vivo was measured by an isotope-dilution method, which calculated the extent of dilution of injected [(14)C]glucose by glucose newly synthesized in the kidney. The extent of dilution was determined from the difference between the decrease of the actual blood glucose concentration and that of the radioactivity of [(14)C]glucose, after injecting [(14)C]glucose into functionally hepatectomized rats. The results indicate that the net glucose release by the kidney in vivo in normal fed rats was 0.75+/-0.13 mg/dl per min, and that its contribution to blood glucose was 25.9+/-5.0%. When unilateral nephrectomy was performed, under the same conditions, renal net glucose release was one-half of that in rats with two intact kidneys, which indicates the quantitative accuracy of the isotope-dilution method employed in this study. In rats starved for 24 h, the renal net glucose release increased to 0.99+/-0.08 mg/dl per min. Diabetic rats showed a remarkably higher renal net glucose of 2.28+/-0.33 mg/dl per min, which was 360% of the normal level. Treatment of diabetic rats with insulin, restored the renal net glucose release to the normal level. In acidotic rats, renal net glucose release was as great as 1.03+/-0.15 mg/dl per min, which suggests that the acid-base balance participates in control of renal glucose output. Measurements every 6 h throughout the day showed that glucose was supplied from the kidney at a constant rate without any circadian rhythm. These data suggest that renal gluconeogenesis is of physiological importance in the maintenance of homeostasis of blood glucose.
Transfer-Printing of Tunable Porous Silicon Microcavities with Embedded Emitters (2014)

Here we demonstrate, via a modified transfer-printing technique, that electrochemically fabricated porous silicon (PSi) distributed Bragg reflectors (DBRs) can serve as the basis of high-quality hybrid microcavities compatible with most forms of photoemitters. Vertical microcavities consisting of an emitter layer sandwiched between 11- and 15-period PSi DBRs were constructed. The emitter layer included a polymer doped with PbS quantum dots, as well as a heterogeneous GaAs thin film. In this structure, the PbS emission was significantly redistributed to a 2.1 nm full-width at half-maximum around 1198 nm, while the PSi/GaAs hybrid microcavity emitted at 902 nm with a sub-nanometer full-width at half-maximum and quality-factor of 1058. Modification of PSi DBRs to include a PSi cavity coupling layer enabled tuning of the total cavity optical thickness. Infiltration of the PSi with Al2O3 by atomic layer deposition globally red-shifted the emission peak of PbS quantum dots up to ∼18 nm (∼0.9 nm per cycle), while introducing a cavity coupling layer with a gradient optical thickness spatially modulated the cavity resonance of the PSi/GaAs hybrid such that there was an ∼30 nm spectral variation in the emission of separate GaAs modules printed ∼3 mm apart.
Clearance of Sodium Fluorescein Incorporated Into Microspheres From the Vitreous After Intravitreal Injection (1991)

The clearance of microsphere-bound fluorescein from the vitreous was studied in rabbits to evaluate microspheres as a controlled-release drug delivery system. Microspheres of different combinations of copolymers of lactic and glycolic acid were injected intravitreally in three groups of rabbits. High concentrations were detected in the vitreous of all groups within 24 hours. By 5 days, the levels had gradually decreased, but they remained measurable up to 16 days in the rabbits in which lactide microspheres had been injected. Clearance was more rapid in the lactide/glycolide combination group than in the lactide group.
Changes in Phenolic Concentrations during Recurrent Selection for Resistance to the Mediterranean Corn Borer (Sesamia nonagrioides Lef.) (2008)

Recurrent selection has been reported as successful for improving maize resistance against corn borers. This study was conducted to determine if phenolics concentration in maize changes during recurrent selection to improve stalk resistance to the Mediterranean corn borer. Three cycles of selection [EPS12(S)C0, ESP12(S)C2, and EPS12(S)C3] from the maize synthetic population EPS12 and test crosses to inbred lines A639, B93, and EP42 were field grown and artificially infested with Mediterranean corn borer larvae, and the pith tissues were sampled for biochemical analyses. Two major simple phenolic acids [p-coumaric (p-CA) and trans-ferulic (E-FA) acids] were identified in free and cell-wall fractions, whereas four isomers of diferulic acid (DFA) (8-5'l, 5-5', 8-o-4', and 8-5' benzofuran form) were present in the cell-wall bound fraction. The selection cycles EPS12(S)C0 and EPS12(S)C3 showed less damage and higher cell wall phenolics concentrations than the cycle EPS12(S)C2. In addition, higher concentrations of total DFAs were associated with shorter tunnel length and lower numbers of larvae per stem. The current study shows new and concrete evidence that the cell-wall bound phenolics could have a determinative role in the resistance to the Mediterranean corn borer, although future development of recurrent and divergent selection cycles will clarify this point.
A taxonomy for secure object-oriented databases (1994)

This paper proposes a taxonomy for secure object-oriented databases in order to clarify the issues in modeling and implementing such databases. It also indicates some implications of the various choices one may make when designing such a database. Most secure database models have been designed for relational databases. The object-oriented database model is more complex than the relational model. For these reasons, models for secure object-oriented databases are more complex than their relational counterparts. Furthermore, since views of the object-oriented model differ, each security model has to make some assumptions about the object-oriented model used for its particular database. A number of models for secure object-oriented databases have been proposed. These models differ in many respects, because they focus on different aspects of the security problem, or because they make different assumptions about what constitutes a secure database or because they make different assumptions about the object-oriented model. The taxonomy proposed in this paper may be used to compare the various models: Models that focus on specific issues may be positioned in the broader context with the aid of the taxonomy. The taxonomy also identifies the major aspects where security models may differ and indicates some alternatives available to the system designer for each such design choice. We show some implications of using specific alternatives. Since differences between models for secure object-oriented databases are often subtle, a formal notation is necessary for a proper comparison. Such a formal notation also facilitates the formal derivation of restrictions that apply under specific conditions. The formal approach also gives a clear indication about the assumptions made by us—given as axioms—and the consequences of those assumptions (and of design choices made by the model designer)—given as theorems.
Activatable cell penetrating peptides for imaging protease activity in vivo (2008)

Aberrant protease activity is a shared feature of most degenerative pathophysiologies, and could potentially have diagnostic as well as prognostic value several major diseases such as cancer, atherosclerosis and stroke if it could be visualized clinically. Here we have designed and validated a new methodology for looking at protease activity in live animals. In their simplest form, activatable cell penetrating peptides (ACPP's) are hairpin shaped molecules that are comprised of a polycationic cell penetrating peptide, a neutralizing polyanion separated by a protease cleavable linker. In the presence of protease, the linker is cleaved and the released polycation can freely associate with cells. To detect these molecules in vivo, a payload such as a fluorophore or a T1 imaging agent is attached to the polycation. We have found that MMP cleavable ACPP's give fluorescence contrast ratios of up to 3-fold in tumors and atherosclerosis and thrombin cleavable agents give up to ten-fold contrast in stroke. Uptake is inhibited by commercially available MMP and thrombin inhibitors as well as by genetically knocking out MMP's. Attaching a large molecular weight carrier causes accumulation of fluorophores to increase further, and by attaching several gadolinium chelates to a single carrier it is possible to deliver micromolar amounts of gadolinium to tumors, allowing visualization by T1 MRI without loss of protease dependence. A dual labeled probe allows localization of tumor proteases by both MRI and fluorescence, and may have clinical utility for image guided surgery. We conclude that ACPP's represent a valid approach for detecting activity of specific proteases in a variety of degenerative disease processes, and may even be useful in the clinic
The Triumph of Zinc: A Short and Highly Efficient Synthesis of the Calyculin C1-C9 Tetraene Building Block by Negishi Coupling (1999)

A short and highly efficient synthesis of phosphonate 5, a key building block of the C1-C9 tetraene fragment of calyculins and calyculinamides, has been achieved. The key step involves a novel, highly chemoselective Negishi coupling with a bismetallic reagent 13.
Secretion incompetence of bovine pancreatic trypsin inhibitor expressed in Escherichia coli. (1991)

There is increasing evidence that protein folding and protein export are competing processes in prokaryotic cells. Virtually all secretion studies reported to date, however, have employed proteins that are relatively uncharacterized in terms of their folding behavior and three-dimensional structure. In contrast, the structural and biochemical parameters governing the folding of bovine pancreatic trypsin inhibitor (BPTI) and several of its mutants have been studied intensively. We therefore undertook a study of the secretion behavior in Escherichia coli of recombinant BPTI and its mutants. Wild-type BPTI and two well-characterized folding mutants (C14A, C38A)BPTI and (C30A, C51A)BPTI (missing the 14-38 and 30-51 disulfide bonds, respectively), were investigated by analyzing their expression fused to an E. coli signal sequence or to two synthetic IgG-binding domains of staphylococcal protein A. Both disulfide mutants are destabilized relative to wild-type BPTI and exhibit markedly altered folding kinetics: one (C14A, C38A) folds more slowly than wild-type BPTI and the other (C30A, C51A) unfolds more rapidly. Both mutants were observed to be exported 3-10 times more efficiently than the wild-type molecule. Moreover, the levels of unprocessed preprotein in the cytoplasm were severalfold higher for the wild-type fusion than for the fusion to the two folding mutants. Intracellular degradation of the BPTI moiety was also observed. These results are consistent with traffic of intracellular BPTI preproteins on at least three routes along the secretory pathway: (a) facile secretion of unfolded material, (b) intracellular folding leading to secretion blockage, and (c) degradation followed by export of truncated molecules. A novel feature of these findings is the implication that disulfide bonds can form in the bacterial cytoplasm and lead to secretion incompetence.
The heat shock response of Synechocystis sp. PCC 6803 analysed by transcriptomics and proteomics (2006)

When cells of the cyanobacterium Synechocystis sp. PCC 6803 are exposed to high temperature they perceive changes in the growth conditions and regulate the expression of genes and synthesize heat-inducible proteins as a response to the heat stress. DNA microarray analysis revealed that genes for chaperonins and proteases, such as groESL1, groEL2, htpG, hspA, and clpB1 were transiently induced after incubation of the cells at 44 °C for 20 min. Quantitative two-dimensional gel electrophoresis revealed that the levels of these chaperonins and proteases were elevated after incubation of cells at 44 °C for 60 min. These findings indicated that levels of the mRNAs and proteins of chaperonins were well correlated in the cells of Synechocystis. However, the level of elongation factors are mainly regulated at the protein level. These results indicated that acclimation to the heat-shock conditions might be governed by transcriptional and translational regulation in Synechocystis.
<title>Closed multilayer dynamic neural network for pattern time sequence processing</title> (1994)

A closed multilayer dynamic neural network, unlike a nonclosed one, can form infinite pattern sequences, both periodic and aperiodic. The closing enhances interactions between time pattern sequences and formation of new sequences. Methods of recording time sequences are considered; prospects of use are discussed.
Perspectives in the Modeling and Optimization of PHB Production by Pure and Mixed Cultures (2005)

Poly(beta-hydroxybutyrate) or PHB is an important member of the family of polyhydroxyalkanoates with properties that make it potentially competitive with synthetic polymers. In addition, PHB is biodegradable. While the biochemistry of PHB synthesis by microorganisms is well known, improvement of large-scale productivity requires good fermentation modeling and optimization. The latter aspect is reviewed here. Current models are of two types: (i) mechanistic and (ii) cybernetic. The models may be unstructured or structured, and they have been applied to single cultures and co-cultures. However, neither class of models expresses adequately all the important features of large-scale non-ideal fermentations. Model-independent neural networks provide faithful representations of observations, but they can be difficult to design. So hybrid models, combining mechanistic, cybernetic and neural models, offer a useful compromise. All three kinds of basic models are discussed with applications and directions toward hybrid model development.
Development of flower buds in thin‐layer cultures of floral stalk tissue from tobacco: Role of hormones in different stages (1984)

The in vitro development of flower buds was studied on tissue explants of epidermis and subepidermal cortex from the flower stalks of Nicotiana tabacum L. cv. Samsun. The number of flower buds formed depended mainly on cytokinin concentration. Auxin acted as a modifier in a complex way. In early development, NAA at 1 μ M decreased the number of buds initiated and delayed bud emergence. At a later stage, auxin promoted bud outgrowth at the same concentration. Optimal results were obtained when explants were first incubated at low auxin concentration for 3–5 days and subsequently transferred to an elevated auxin level. Physiological processes that lead to flower bud initiation start very soon after the onset of incubation. This was inferred from experiments whereby explants were first cultured at an inductive cytokinin concentration and then transferred to a non‐inductive hormone level.
Determination of Electric Conductivity and Local SAR Via B1 Mapping (2009)

The electric conductivity can potentially be used as an additional diagnostic parameter, e.g., in tumor diagnosis. Moreover, the electric conductivity, in connection with the electric field, can be used to estimate the local SAR distribution during MR measurements. In this study, a new approach, called electric properties tomography (EPT) is presented. It derives the patient's electric conductivity, along with the corresponding electric fields, from the spatial sensitivity distributions of the applied RF coils, which are measured via MRI. Corresponding numerical simulations and initial experiments on a standard clinical MRI system underline the principal feasibility of EPT to determine the electric conductivity and the local SAR. In contrast to previous methods to measure the patient's electric properties, EPT does not apply externally mounted electrodes, currents, or RF probes, thus enhancing the practicality of the approach. Furthermore, in contrast to previous methods, EPT circumvents the solution of an inverse problem, which might lead to significantly higher spatial image resolution.
Unification of ultra-wideband multiple access schemes and comparison in the presence of interference (2004)

Interference constitutes the bottleneck of ultra-wideband (UWB) communications that has been regulated to overlay coexisting narrowband communication systems. To quantify interference and compare UWB systems on that basis, this paper develops a unifying transmission and Rake reception model for UWB multiple access encompassing existing and novel spreading codes. Multiband UWB systems using single- or multicarrier modulation are also introduced. Performance analysis (in closed-form) and simulations assess the relative merits of several UWB systems in narrowband interference (NBI), multipath and additive white Gaussian noise (AWGN) effects, for both matched-filter (MF), and minimum mean-square error (MMSE) Rake receivers.
A new technique for removal of amorphous phase tissue water without ice crystal damage: a preparative method for ultrastructural analysis and immunoelectron microscopy. (1986)

An apparatus has been produced that can remove amorphous phase tissue water via molecular distillation without devitrification or rehydration. This method represents a fundamental advance in tissue preparation, making possible for the first time ultrastructural localization of soluble molecular entities without the problems of alteration, re-distribution, and loss which have plagued conventional techniques. Fresh slices of rat brain, liver, or kidney, and monkey retinal tissue were cryofixed by bounce-free, metal mirror cooling on copper bars immersed in liquid nitrogen (LN2). Tissue transferred under LN2 was then placed in a precooled copper specimen block, which was subsequently lowered into a LN2-cooled stainless steel chamber. After rough pumping at 1 X 10(-3) mbar with a mechanical pump to remove LN2, the chamber was evacuated with a cryopump or turbomolecular pump to achieve a hydrocarbon-free, ultra-high vacuum of 1 X 10(-8) mbar. Equilibrium temperature in the chamber before the drying cycle was -192 degrees C. The copper specimen block was equipped with a thermocouple and a programmable feedback-controlled heating circuit. Tissue was dried by increasing the specimen block temperature 1 degree C/hr during the critical drying phase while monitoring the rate of water removal with a partial pressure analyzer. Results obtained indicate that drying is complete below the devitrification temperature of amorphous phase tissue water. Dried tissue was fixed with osmium tetroxide vapor, vacuum-embedded in a low-viscosity epoxy resin, sectioned, stained, and viewed with the electron microscope. Processed tissue exhibits excellent morphological preservation without the use of pre-fixation or cryoprotective agents. Thin sections of this tissue are excellent for immunocytochemical staining and electron microprobe analysis.
Pharmaceutical Coating Technology (1995)

Pharmaceutical coating technology , Pharmaceutical coating technology , کتابخانه مرکزی دانشگاه علوم پزشکی تهران
THE MOLECULAR STRUCTURE OF CENTROMERES AND TELOMERES (1984)

The Hippo pathway was initially discovered in Drosophila melanogaster as a key regulator of tissue growth. It is an evolutionarily conserved signaling cascade regulating numerous biological processes, including cell growth and fate decision, organ size ...Read More
Micelles and Hollow Nanospheres Based on e-Caprolactone-Containing Polymers in Aqueous Media The National Natural Science Foundation of China (NNSFC, Nos. 29992590 and 50173006) and Ministry of Education of China is acknowledged for supporting this research. (2002)

Von Blockcopolymeren unabhängig war die Strategie, mit der Micellen durch Selbstorganisation von Poly(ε-caprolacton) (PCL) und einem Copolymer, das ein hydrophiles Rückgrat und kurze PCL-Seitenketten hat, erzeugt wurden (siehe schematische Darstellung). Die Affinität zwischen dem PCL-Homopolymer und den kurzen PCL-Seitenarmen scheint die Micellen zu stabilisieren. Der hydrophobe Polyesterkern kann selektiv durch eine Lipase hydrolisiert werden, sodass eine hohle Kugel entsteht, wie transmissionselektronenmikroskopisch gezeigt werden konnte.
A Multi-Omic Systems-Based Approach Reveals Metabolic Markers of Bacterial Vaginosis and Insight into the Disease (2013)

The results not only provide useful diagnostic biomarkers, but also may ultimately provide much needed insight into the determinants of BV.
Residence proximity to benzene release sites is associated with increased incidence of non‐Hodgkin lymphoma (2013)

NHL incidence was significantly higher in census tracts that were closer, on average, to benzene release sites. Additional studies are needed to examine spatial patterns of NHL incidence in other geographic regions and interactions between benzene and other exposures.