gebhart/patrepeval huggingface dataset:
Molecular Recognition of Histidine-Tagged Molecules by Metal-Chelating Lipids Monitored by Fluorescence Energy Transfer and Correlation Spectroscopy (1998)

Complex binding of proteins by metal-chelating lipids via surface-exposed or protein-engineered histidines provides an universal and powerful concept for the orientation and two-dimensional crystallization of proteins at self-organized interfaces. To demonstrate pair formation between individual histidine-tagged molecules and chelator lipids on the molecular level, we have synthesized novel lipids bearing both a Ni−NTA chelator and a fluorescent group. These lipids serve as spectroscopic probes to visualize directly the molecular recognition of fluorescence-labeled histidine-tagged peptides by metal-chelating lipids using fluorescence resonance energy transfer (FRET). The molecular docking to chelator lipids assembled in mono- or bilayers is highly specific, revealing only 3% unspecific adsorption and a binding constant of 3 μM. The affinity constant was confirmed by fluorescence correlation spectroscopy (FCS) on single molecules, where the ratio of lipid-bound to free was analyzed by their intrinsically different diffusion times passing through a confocal volume of about 1 fL. By using a model peptide most of the electrostatic and steric contribution to the binding process can be neglected. Therefore, the affinity constant can serve as a standard value for the binding of histidine-tagged proteins to chelator lipid interfaces.
Very compact double C-patch antenna (1998)

A miniaturised C-patch antenna excited by means of a coaxial probe is described. The antenna consists of two stacked C-shaped elements connected together with a vertical conducting plane. The antenna is designed on an air substrate and offers attractive dimensions, being five times lower than those of a conventional half wavelength microstrip patch antenna operating at the same frequency. A 10 dB bandwidth of 3% is obtained. The voltage standing wave ratio, radiation patterns, and electric surface current density are presented.
Goitre in Two African Sculptures (1968)

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LIPID CONSTITUENTS OF BLACK WALNUT KERNELS (1979)

ABSTRACT Lipids from the kernels of black walnuts (Juglans nigra L.) were quantitated and identified by thin‐layer chromatography and gas‐liquid chromatography‐mass spectrometry. Four classes of lipids were prominent in the walnut oils and were identified as complex lipids, α, β‐diglycerides, sterols, and triglycerides. Triglycerides were the predominant class and comprised 99.9% of the lipids. Twenty‐one fatty acids were isolated and identified. Among these, unsaturated fatty acids were predominant and comprised ca 92% of the fatty acids. On the basis of total fatty acids, octadecenoic and octadecadienoic acids comprised 86.1%. Twelve acids were present in trace amounts and accounted for ca 0.06% of the total.
Development of CS-TPP-dsRNA nanoparticles to enhance RNAi efficiency in the yellow fever mosquito, Aedes aegypti (2019)

Mosquito-borne diseases are a major threat to human health and are responsible for millions of deaths globally each year. Vector control is one of the most important approaches used in reducing the incidence of these diseases. However, increasing mosquito resistance to chemical insecticides presents challenges to this approach. Therefore, new strategies are necessary to develop the next generation vector control methods. Because of the target specificity of dsRNA, RNAi-based control measures are an attractive alternative to current insecticides used to control disease vectors. In this study, Chitosan (CS) was cross-linked to sodium tripolyphosphate (TPP) to produce nano-sized polyelectrolyte complexes with dsRNA. CS-TPP-dsRNA nanoparticles were prepared by ionic gelation method. The encapsulation efficiency, protection of dsRNA from nucleases, cellular uptake, in vivo biodistribution, larval mortality and gene knockdown efficiency of CS-TPP-dsRNA nanoparticles were determined. The results showed that at a 5:1 weight ratio of CS-TPP to dsRNA, nanoparticles of less than 200 nm mean diameter and a positive surface charge were formed. Confocal microscopy revealed the distribution of the fed CS-TPP-dsRNA nanoparticles in midgut, fat body and epidermis of yellow fever mosquito, Aedes aegypti larvae. Bioassays showed significant mortality of larvae fed on CS-TPP-dsRNA nanoparticles. These assays also showed knockdown of a target gene in CS-TPP-dsRNA nanoparticle fed larvae. These data suggest that CS-TPP nanoparticles may be used for delivery of dsRNA to mosquito larvae.
Carbon dioxide concentrations in the environment of sleeping infants (1994)

In 22 infants continuous measurements were made of the concentration of carbon dioxide (CO2) in inspired air during sleep. Evidence was found of CO2 enrichment of inspired air in certain environmental conditions. The levels achieved were not sufficiently high to acutely endanger an infant. Carbon dioxide concentrations as high as 2-3% were observed in the prone position when the infant's head was under a blanket and when the lower face was obscured by bedding. Sleeping prone on a sheepskin also resulted in an increased concentration of CO2 but to a lesser extent than being under a blanket. In awake infants the presence of a pacifier also promoted an excess of CO2 in the inspired air, both in the prone and supine positions. The physiological and clinical implications of these findings, in relation to the Sudden Infant Death Syndrome (SIDS), are unknown and warrant investigation.
Correlational analysis of central noradrenergic neuronal activity and sympathetic tone in behaving cats (1986)

The activity of the noradrenergic (NA) neurons of the feline locus coeruleus complex (LCx) were correlated with changes in peripheral sympathetic tone in behaving cats. LCx NA neurons exhibit stereotypical changes in discharge rate across behavioral states, falling virtually silent during paradoxical sleep (PS). Simultaneous recordings from LCx NA neurons and the cervical sympathetic trunk demonstrated a tonic reduction in nerve activity during PS as well. LCx NA neurons were also found to fall silent during induction of the scruff immobility reflex and significant pupillary miosis was seen during this behavior as well. These data support the hypothesis that NA neurons in the brain are a central analogue of the peripheral sympathetic system and demonstrate that the two systems operate in an integrated fashion in the behaving cat.
Host-specific induction of <i>Escherichia coli</i> fitness genes during human urinary tract infection (2014)

Uropathogenic Escherichia coli (UPEC) is the predominant etiological agent of uncomplicated urinary tract infection (UTI), manifested by inflammation of the urinary bladder, in humans and is a major global public health concern. Molecular pathogenesis of UPEC has been primarily examined using murine models of UTI. Translational research to develop novel therapeutics against this major pathogen, which is becoming increasingly antibiotic resistant, requires a thorough understanding of mechanisms involved in pathogenesis during human UTIs. Total RNA-sequencing (RNA-seq) and comparative transcriptional analysis of UTI samples to the UPEC isolates cultured in human urine and laboratory medium were used to identify novel fitness genes that were specifically expressed during human infection. Evidence for UPEC genes involved in ion transport, including copper efflux, nickel and potassium import systems, as key fitness factors in uropathogenesis were generated using an experimental model of UTI. Translational application of this study was investigated by targeting Cus, a bacterial copper efflux system. Copper supplementation in drinking water reduces E. coli colonization in the urinary bladder of mice. Additionally, our results suggest that anaerobic processes in UPEC are involved in promoting fitness during UTI in humans. In summary, RNA-seq was used to establish the transcriptional signature in UPEC during naturally occurring, community acquired UTI in women and multiple novel fitness genes used by UPEC during human infection were identified. The repertoire of UPEC genes involved in UTI presented here will facilitate further translational studies to develop innovative strategies against UTI caused by UPEC.
Synthesis of Versatile Chiral N,P Ligands Derived from Pyridine and Quinoline (2003)

Potent transition-metal complexes for asymmetric catalysis are formed from readily accessible N,P ligands constructed from basic N-heteroaryl building blocks (see structure). Their simple assembly should not be misconstrued: they posses several handles by which to tune both steric and electronic parameters. The potential of these ligands is demonstrated by the high levels of enantioselection they induce in such divergent processes as asymmetric hydrogenation and the Heck reaction.
A laser induced cavitation pump (2004)

We demonstrate and discuss a liquid pumping effect based on the interaction between periodically generated cavitation microbubbles and a millimeter diameter tube. The bubbles are generated by the heat of laser adsorption at the tip of an optical fiber immersed in liquid. When the bubbles are generated well away from the tube, a steady streaming flow with a relatively large and energetic ring vortex is observed. Coaxial placement of the fiber within the tube, with the fiber tip near one end of the tube, results in relatively weak pumping of liquid. In contrast, placement of the fiber outside the tube with a similar fiber tip position results in a synergetic and strong pumping effect. This paper presents quantitative measures of pumping performance as a function of relevant parameters including the axial fiber tip position, fiber orientation and laser duty cycle.
On the determination of the position of extrema of sampled correlators (1991)

The problem of determination of the position of the extremum of a continuous correlator function from its samples, if the spectrum of the correlator is not bandlimited, is discussed. Searching for the position of the extremum by fitting a parabola through three samples around that extremum leads to clustering of the estimates around values corresponding with the sampling moments.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Behoeftebepaling vir ontspanningsvoorsiening: 'n Praktiese benaderingswyse (1991)

Abstract Needs determination in making provision for recreation: a practical approach. The effective provision of recreational facilities for a community calls for the correct identification of the needs of that community. Recreational facilities usually require a large capital outlay, and in order to utilize scarce resources efficiently, care must be taken to ensure that the true needs of the community are accommodated. It is in this area in particular that problems are experienced. A recent investigation into recreation in the urban black townships of the Pretoria-Witwatersrand-Vereeniging region, found that a primary cause of inadequate recreational facilities was that the communities' needs had not been properly determined. This situation is most probably not limited to black townships. The meaning attached to the concept needs in this discussion is clearly defined, With a view to effective planning, Bradshaw's taxonomy (1972) is used as a basis for a suitable system of determining the recreational needs of a developing community. The practical value of this system is demonstrared in its application to the determination of the needs of communities in seven black townships. The information culminates in a taxonomy that not only contains the specific needs but also establishes their order of priority. A comprehensive image thus emerges of the recreational needs of the area under consideration. With minor adjustments for varying local circumstances, this system could be applied to all communities where planning for the effective provision of recreational facilities is important.
Metoprolol compared to carvedilol deteriorates insulin-stimulated endothelial function in patients with type 2 diabetes - a randomized study (2010)

Current Controlled Trials NCT00497003.
Structure, function and evolution of the Archaeal class I fructose-1,6-bisphosphate aldolase (2004)

FBPA (fructose-1,6-bisphosphate aldolase) catalyses the reversible aldol condensation of glyceraldehyde 3-phosphate and dihydroxyacetone phosphate to form fructose 1,6-bisphosphate. Two classes of FBPA, which rely on different reaction mechanisms, have so far been discovered, class I mainly found in Eucarya and class II mainly in Bacteria. Only recently were genes encoding proteins with FBPA activity identified in Archaea. Archaeal FBPAs do not share any significant overall sequence identity with members of the traditional classes of FBPAs, raising the interesting question of whether they have evolved independently by convergent evolution or diverged from a common ancestor. Biochemical characterization of FBPAs of the two hyperthermophilic Archaea Thermoproteus tenax and Pyrococcus furiosus showed that the enzymes use a Schiff-base mechanism and thus belong to the class I aldolases. The crystal structure of the archaeal FBPA from T. tenax revealed that the protein fold, as for the classical FBPA I and II, is that of a parallel (betaalpha)(8) barrel. A substrate-bound crystal structure allowed detailed active-site comparisons which showed the conservation of six important catalytic and substrate-binding residues between the archaeal and the classical FBPA I. This observation provides further evidence that the two sequence families of proteins share a common evolutionary origin. Furthermore, structure and sequence analysis indicate that the class I FBPA shares a common evolutionary origin with several other enzyme superfamilies of the (betaalpha)(8) barrel fold.
The effect of stimulus height on visual discrimination in horses1 (2003)

This study investigated the effect of stimulus height on the ability of horses to learn a simple visual discrimination task. Eight horses were trained to perform a two-choice, black/white discrimination with stimuli presented at one of two heights: ground level or at a height of 70 cm from the ground. The height at which the stimuli were presented was alternated from one session to the next. All trials within a single session were presented at the same height. The criterion for learning was four consecutive sessions of 70% correct responses. Performance was found to be better when stimuli were presented at ground level with respect to the number of trials taken to reach the criterion (P < 0.05), percentage of correct first choices (P < 0.01), and repeated errors made (P < 0.01). Thus, training horses to carry out tasks of visual discrimination could be enhanced by placing the stimuli on the ground. In addition, the results of the present study suggest that the visual appearance of ground surfaces is an important factor in both horse management and training.
Biochemical and Structural Evaluation of Highly Selective 2-Arylbenzoxazole-Based Transthyretin Amyloidogenesis Inhibitors (2007)

To develop potent transthyretin (TTR) amyloidogenesis inhibitors that also display high binding selectivity in blood, it proves useful to systematically optimize each of the three substructural elements that comprise a typical inhibitor: the two aryl rings and the linker joining them. In the first study, described herein, structural modifications to one aryl ring were evaluated by screening a library of 2-arylbenzoxazoles bearing thyroid hormone-like aryl substituents on the 2-aryl ring. Several potent and highly selective amyloidogenesis inhibitors were identified that exhibit minimal thyroid hormone nuclear receptor and COX-1 binding. High resolution crystal structures (1.3-1.5 A) of three inhibitors (2f, 4f, and 4d) in complex with TTR were obtained to characterize their binding orientation. Collectively, the results demonstrate that thyroid hormone-like substitution patterns on one aryl ring lead to potent and highly selective TTR amyloidogenesis inhibitors that lack undesirable thyroid hormone receptor or COX-1 binding.
Mechanistic Studies of the Genetically Encoded Fluorescent Protein Voltage Probe ArcLight (2014)

ArcLight, a genetically encoded fluorescent protein voltage probe with a large DF/ DV, is a fusion between the voltage sensing domain of the Ciona instestinalis voltage sensitive phosphatase and super ecliptic pHluorin carrying a single mutation (A227D in the fluorescent protein). Without this mutation the probe produces only a very small change in fluorescence in response to voltage deflections (,1%). The large signal afforded by this mutation allows optical detection of action potentials and sub-threshold electrical events in single-trials in vitro and in vivo. However, it is unclear how this single mutation produces a probe with such a large modulation of its fluorescence output with changes in membrane potential. In this study, we identified which residues in super ecliptic pHluorin (vs eGFP) are critical for the ArcLight response, as a similarly constructed probe based on eGFP also exhibits large response amplitude if it carries these critical residues. We found that D147 is responsible for determining the pH sensitivity of the fluorescent protein used in these probes but by itself does not result in a voltage probe with a large signal. We also provide evidence that the voltage dependent signal of ArcLight is not simply sensing environmental pH changes. A two-photon polarization microscopy study showed that ArcLight's response to changes in membrane potential includes a reorientation of the super ecliptic pHluorin. We also explored different changes including modification of linker length, deletion of nonessential amino acids in the super ecliptic pHluorin, adding a farnesylation site, using tandem fluorescent proteins and other pH sensitive fluorescent proteins.
Post-transcriptional regulation of miR-27 in murine cytomegalovirus infection (2010)

In mammals, microRNAs (miRNAs) can play diverse roles in viral infection through their capacity to regulate both host and viral genes. Recent reports have demonstrated that specific miRNAs change in expression level upon infection and can impact viral production and infectivity. It is clear that miRNAs are an integral component of viral-host interactions, and it is likely that both host and virus contain mechanisms to regulate miRNA expression and/or activity. To date, little is known about the mechanisms by which miRNAs are regulated in viral infection. Here we report the rapid down-regulation of miR-27a in multiple mouse cell lines as well as primary macrophages upon infection with the murine cytomegalovirus. Down-regulation of miR-27a occurs independently from two other miRNAs, miR-23a and miR-24, located within the same genomic cluster, and analysis of pri-miRNA levels suggest that regulation occurs post-transcriptionally. miR-27b, a close homolog of miR-27a (20/21 nucleotide identity), also decreases upon infection, and we demonstrate that both miR-27a and miR-27b exert an antiviral function upon over-expression. Drug sensitivity experiments suggest that virus entry is not sufficient to induce the down-regulation of miR-27 and that the mechanism requires synthesis of RNA. Altogether, our findings indicate that miR-27a and miR-27b have antiviral activity against MCMV, and that either the virus or the host encodes molecule(s) for regulating miR-27 accumulation, most likely by inducing the rapid decay of the mature species.
Improving Mobile Search through Location Based Context and Personalization (2012)

In this paper, we present a novel method for deep user profiling using information available on social networks about a user's activities and interests. We use this information to personalize the search for the user and make results available via web and low end mobile phones. In addition to using a user's profile as a context, we also use the context of location and implement a location based search engine for low end mobile phones. Finally, we combine the two contexts and implement a location based personalized search engine accessible from a low end mobile phone. There has been much work already done in trying to personalize search results based on user profiling. The top search engines attempt to build a user profile based on usage history and then use that to customize search. However, there have been fewer attempts to personalize search based on a deep understanding of a user's activities and preferences. In this work, we attempt to do this.
Characterization of electron beam crosslinked poly(styrene‐block‐ethylene‐co‐butylene‐block‐styrene) (1983)

Abstract A saturated triblock copolymer, poly(styrene‐block‐ethylene‐co‐butylene‐block‐styrene) was chemically crosslinked using trimethylol propane trimethacrylate, TMPTM, and subjected to electron beam radiation. The gel percent, Gehman ten second modulus, and stress relaxation were measured to characterize the materials as a function of crosslinker concentration and radiation level. A time‐temperature super‐position master curve was generated at 63°C for 3 percent TMPTM and 5 Mrads of radiation, which indicated rubbery plateau behavior at long times of measurement, as opposed to the uncrosslinked material, which continued to creep and flow. The main locus of crosslinking was within the polystyrene phase, which explains reduced creep and stress relaxation only for long times of measurement and/or high temperatures. Based on shifts of the glass transition temperatures, it was estimated that 11 to 16 percent poly(ethylene‐co‐butylene) was dissolved in the polystyrene phase.
Topical vitamin e inhibition of immunosuppression and tumorigenesis induced by ultraviolet irradiation (1991)

Abstract Ultraviolet (UV) irradiation of C3H/HeN mice induces skin cancer and an immunosuppression that prevents the host from rejecting antigenic UV‐induced tumors. The capacity of topical vitamin E (dl‐α‐tocopherol) to prevent photocarcinogenesis or the immunosuppression induced by UV irradiation were assessed. Skin cancer incidence in UV‐irradiated mice was 81 % at 33 weeks after the first UV exposure; application to mice of 25 mg vitamin E three times per week for three weeks before UV irradiation, and throughout the experiment, reduced this incidence to 42% (p = 0.0065, log rank test). Immuno‐enhancement by vitamin E was assessed by comparing levels of immunosuppression by splenocytes from normal or UV‐irradiated mice, with and without topical vitamin E treatment. Transfer of splenocytes from UV‐irradiated mice to naive mice prevented the recipients from rejecting a UV‐induced tumor challenge, whereas splenocytes from UV‐irradiated mice treated with vitamin E did not prevent recipients from rejecting a similar tumor challenge. Phenotypic analysis of splenocytes used in the passive transfer assay, conducted with a biotin‐avidin‐immunoperoxidase technique, revealed that vitamin E treatment of mice undergoing UV irradiation prevented the UV‐induced down regulation of la expression in splenocytes and increased the proportion of Lyt‐2+ and L3T4+ splenocytes. Therefore, chronically applied vitamin E can effectively reduce cancer formation and immunosuppression induced by UV irradiation. Prevention of UV‐induced down regulation of la expression may have contributed to this immunomodulation.