gebhart/patrepeval huggingface dataset:
Fabricating optical lenses by inkjet printing and heat-assisted<i>in situ</i>curing of polydimethylsiloxane for smartphone microscopy (2015)

We present a highly repeatable, lithography-free and mold-free method for fabricating flexible optical lenses by in situ curing liquid polydimethylsiloxane droplets on a preheated smooth surface with an inkjet printing process. This method enables us to fabricate lenses with a focal length as short as 5.6 mm, which can be controlled by varying the droplet volume and the temperature of the preheated surface. Furthermore, the lens can be attached to a smartphone camera without any accessories and can produce high-resolution (1 μm) images for microscopy applications.
Immune Responses of Specific-Pathogen-Free Mice to Chronic <i>Helicobacter pylori</i> (Strain SS1) Infection (1998)

A model permitting the establishment of persistent Helicobacter pylori infection in mice was recently described. To evaluate murine immune responses to H. pylori infection, specific-pathogen-free Swiss mice (n = 50) were intragastrically inoculated with 1.2 x 10(7) CFU of a mouse-adapted H. pylori isolate (strain SS1). Control animals (n = 10) received sterile broth medium alone. Animals were sacrificed at various times, from 3 days to 16 weeks postinoculation (p.i.). Quantitative culture of gastric tissue samples from inoculated mice demonstrated bacterial loads of 4.0 x 10(4) to 8 x 10(6) CFU per g of tissue in the animals. Infected mice had H. pylori-specific immunoglobulin M (IgM) and IgG antibodies in serum (at day 3 p.i.) and IgG and IgA antibodies in their gastric contents (weeks 4 and 16 p.i.) and saliva (week 16 p.i.). Mucosal IgM antibodies were not detected. Histological examination of the gastric mucosae from control and infected mice revealed mild chronic gastritis, characterized by the presence of polymorphoneutrophil cell infiltrates and submucosal lymphoid aggregates, in infected animals at 16 weeks p.i. Differences in the quantities of IgG1 and IgG2a subclass antibodies detected in the sera of mouse strains (Swiss, BALB/c, and C57BL/6) infected by H. pylori suggested that host factors influence the immune responses induced against this bacterium in the host. In conclusion, immune responses to H. pylori infection in mice, like those in chronically infected humans, appear to be ineffective in resolving the infection.
Optical WDM technology for networking and switching applications (1992)

Optical wavelength-division multiplexing (WDM) is arguably the most attractive technique for accessing the vast bandwidth of the optical fiber. By combining a large number of independently modulated optical wavelengths, one can envision networking and switching systems with an overall throughput that is virtually unattainable by any other means. This potentiality induced many researchers to vigorously investigate optical WDM technology over the past decade. Early work on the subject was based on circuit-switched local-area network architectures utilizing a broadcasting medium (e.g., a star or a bus) to which laser-based transmitters and coherent or filter-based direct-detection receivers are attached. It was recognized that, in such networks, full interconnectivity among the various nodes can be achieved by tuning either the transmitters or the receivers. It was envisioned that the potential number of optical wavelength would be up to a few thousands.
Molecular Analysis of Patterning of Conduction Tissues in the Developing Human Heart (2011)

Our findings point to the comparability of mechanisms governing the development of the cardiac conduction patterning in human and mouse, which provide a molecular basis for understanding the functioning of the human developing heart before formation of a discrete conduction system.
High temperature thermal energy storage systems based on latent and thermo-chemical heat storage (2010)

The increasing of the population and development of the different countries converts
the energy topic in one of the most important aspects of our times. The main target due to the
limited life of conventional energy sources is the achievement of a sustainable energy mix
where thermo solar energy plays an important role. One of the disadvantages of this
renewable energy is the fact that energy is not available all the time: the need of heat storage
systems appear. In this Master Thesis, a review on the work done until the moment in the
frame of latent heat and thermochemical storage systems is presented in the temperature
range from 200 to 700 oC. Finally a design and the first calculations for the modeling of a latent
heat storage system for a laboratory device are shown.
Studies on the mechanism of the adenosylcobalamin-dependent diol dehydrase reaction by the use of analogs of the coenzyme. (1977)

A series of 16 analogs of 5'-deoxy-5'-adenosylcobalamin (adenosylcobalamin) were examined for their effects on the diol dehydrase system of Klebsiella pneumoniae (Aerobacter Aerogenes). Four analogs, ara-adenosyl-, aristeromycyl-, 3-isoadenosyl-, and nebularylcobalamin, were able to function as coenzymes in the diol dehydrase reaction, coenzyme activity decreasing in that order. Like the native holoenzyme, complexes of the enzyme with these four analogs show a cob(II)alamin-like absorption peak or shoulder in the presence of 1,2-propanediol. Analogs containing hypoxanthine, cytosine, or benzimidazole do not function as coenzymes, but are weak competitive inhibitors in the presence of adenosylcobalamin. Analogs in which the D-ribosyl moiety is replaced by L-ribose or by an alkyl chain of 2 to 6 carbons are inactive as coenzymes, but act as competitive inhibitors with extremely high affinity for the apoenzyme. Complexes with the inactive analogs showed visible spectra similar to those of the corresponding free cobalamins. Upon anaerobic photolysis and subsequent aeration, complexes with the first group of inactive analogs produced unusually stabilized cob(II)alamin, while complexes with the second group of inactive analogs were readily photolyzed to a hydroxocobalamin-enzyme complex. Complexes with adeninylpentyl- and L-adenosylcobalamin were stable to light under the same conditions. These findings suggest that both the ribose and the adenine moiety of the nucleoside participate in enzyme-coenzyme interaction, involving not only the binding to the apoenzyme but also the activation of the carbon-cobalt bond.
Preclinical Toxicology Studies with Acyclovir: Genetic Toxicity Tests (1983)

Preclinical Toxicology Studies with Acyclovir: Genetic Toxicity Tests. Clive, D., Turner, N.T., Hozier, J., Batson, A.G. and Tucker, W.E., Jr. (1983). Fundam. Appl. Toxicol 3: 587–602. Acyclovir (ACV), an antiviral drug active in the treatment of oral and genital Herpes infections, has been evaluated for mutagenic and carcinogenic potential in a battery of in vitro and in vivoshort-term assays. Negative results were obtained in the following in vitro tests: Ames Salmonella, plate incorporation and preincubation modification assays; E. coli polA+/polA− DNA repair; yeast (S. cerevisiae D4) gene conversion; Chinese hamster ovary cells (HGPRT, APRT loci and ouabain-resistance marker); L5178 Y mouse lymphoma cells (HGPRT locus and ouabain-resistance marker); and C3H/10T½mouse fibroblast neo-plastic transformation assay. All except the last assay were performed in the presence and absence of an exogenous metabolic activation system. ACV was positive at high concentrations × exposure times in the absence of exogenous metabolic activation in the following in vitro systems and at the indicated concentrations: BALB/c-3T3 neoplastic transformation (50 /μg/mL, 72 h exposure); human lymphocyte cytogenetics (250–500 μg/mL, 48 h exposure); and L5178Y mouse lymphoma cells (TK locus, 400–2400 μg/mL, 4 h exposure; predominantly small colony mutants of chromosomal origin produced). No effects were seen in vivo (mouse dominant lethal assay; rat and Chinese hamster bone marrow cytogenetics) at up to maximum tolerated doses (MTD). An unusual clastogenic effect was seen in Chinese hamsters at 5 times the MTD. Overall, positive effects were seen only at either high concentrations (≥250 μg/mL in vitro or plasma levels) or prolonged exposure (72 hr in the BALB/ c-3T3 neoplastic transformation assay). These studies support the view that ACV is a chromosomal mutagen, i.e., one which causes multi-locus damage but not single gene effects. The significance of these results for the genetic risk of ACV to man is discussed.
MARCH, 1868 (2013)

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Security of instant messaging system (2004)

Instant messaging is an increasingly popular method for communicating over the internet. On the base of introduction to the IM system, various potential security threats arising from the vulnerabilities of current instant messaging systems are discussed. Some suggestions are put forward.
Proline-directed Pseudo-phosphorylation at AT8 and PHF1 Epitopes Induces a Compaction of the Paperclip Folding of Tau and Generates a Pathological (MC-1) Conformation (2008)

Tau, a neuronal microtubule-associated protein that aggregates in Alzheimer disease is a natively unfolded protein. In solution, Tau adopts a "paperclip" conformation, whereby the N- and C-terminal domains approach each other and the repeat domain ( Jeganathan, S., von Bergen, M., Brutlach, H., Steinhoff, H. J., and Mandelkow, E. (2006) Biochemistry 45, 2283-2293 ). In AD, Tau is in a hyperphosphorylated state. The consequences for microtubule binding or aggregation are a matter of debate. We therefore tested whether phosphorylation alters the conformation of Tau. To avoid the ambiguities of heterogeneous phosphorylation we cloned "pseudo-phosphorylation" mutants of Tau where combinations of Ser or Thr residues were converted into Glu. These mutations were combined with FRET pairs inserted in different locations to allow distance measurements. The results show that the paperclip conformation becomes tighter or looser, depending on the pseudo-phosphorylation state. In particular, pseudo-phosphorylation at the epitope of the diagnostic antibody AT8* (S199E + S202E + T205E) moves the N-terminal domain away from the C-terminal domain. Pseudo-phosphorylation at the PHF1 epitope (S396E + S404E) moves the C-terminal domain away from the repeat domain. In both cases the paperclip conformation is opened up. By contrast, the combination of AT8* and PHF1 sites leads to compaction of the paperclip, such that the N-terminus approaches the repeat domain. The compaction becomes even stronger by combining pseudo-phosphorylated AT8*, AT100, and PHF1 epitopes. This is accompanied by a strong increase in the reaction with conformation-dependent antibody MC1, suggesting the generation of a pathological conformation characteristic for Tau in AD. Furthermore, the compact paperclip conformation enhances the aggregation to paired helical filaments but has little influence on microtubule interactions. The data provide a framework for the global folding of Tau dependent on proline-directed phosphorylation in the domains flanking the repeats and the consequences for pathological properties of Tau.
American Self-Fashioning in Helen Foster Snow's My China Years (2013)

In My China Years: A Memoir, Helen Foster Snow draws upon her Puritan roots in fashioning an American self that affirms the power of an individual exemplary life, the ability to exercise free will amid struggle, an optimism borne of hope, and a way to represent failure and success. Self-fashioning, which Stephen Greenblatt attributes to the rise of an autonomous self in early modern Europe, is shaped by Snow as a distinctly American identity based on a secular Puritanism she found more congenial than the Puritanism of her ancestors on both sides of the Atlantic. The many resemblances noted by Snow between the Chinese Communist Army and seventeenth-century English Puritanism led her to interrogate Puritanism, both in its traditional form and its secularised variant. What emerges in the pages of My China Years is an attempt to fashion an American self by negotiating an old Puritanism with the new by way of a triangulation with China.
The induction of hapten-specific immunologic tolerance and immunity in B lymphocytes. IV. Induction of TNP-specific unresponsiveness in vitro with serum from tolerant mice. (1978)

The serum from mice that had been rendered specifically tolerant (TolS) to the trinitrophenyl (TNP) hapten by the injection of trinitrobenzenesulfonic acid (TNBS) was tested in vitro for its ability to induce unresponsiveness in untreated spleen cells. Conjugated with TNP at a concentration of ≈4 × 10 -4 M, TolS induced complete TNP-specific tolerance in cultures of spleen cells challenged with TNP-lipopolysaccharide (TNP-LPS) and 4-hydroxy-3-iodo-5-nitrophenylacetic acid conjugated polymerized flagellin (NIP-POL). By using normal mouse serum (NMS) as a control, TNP-specific tolerance in the in vitro antibody response was induced by cultivation of spleen cells with amounts of TolS ranging from 10 -4 to 10 -2 ml (equivalent to 4 × 10 -8 to 4 × 10 -6 M TNP) in 1 ml cultures of 10 × 10 6 viable spleen cells. Thymic-derived (T) cells were not required for the induction of the unresponsiveness in TNP-specific bone marrow-derived (bursal equivalent, B) lymphocytes. TolS induced tolerance in cultures challenged with either T cell independent (TI) or T cell dependent (TD) forms of the TNP hapten. TolS was nonimmunogenic under the in vitro culture conditions used, and did not affect control responses. Although it was most effective when harvested 4 or fewer days after TNBS injection of donor mice, TolS exerted a tolerogenic effect if obtained as much as 2 weeks after such treatment. TolS was active across both histocompatibility and immunoglobulin allotype barriers, and also exerted its tolerogenic effect in the presence of concentrations of antigen optimal for the induction of immunity. Complete tolerance was induced by pretreatment of spleen cells with TolS and extensive washing before the addition of immunogen. Following dose response kinetics, the time required and the level of unresponsiveness induced during preincubation with TolS were directly related to the dose of tolerogen utilized. The inability of TNP-lysine to act as a tolerogen and the nondialysable nature of TolS suggested that the active component of this serum is a macromolecule and not merely TNBS. Fractionation of TolS by (NH 4 ) 2 SO 4 resulted in virtually complete recovery of the tolerogenic activity in the globulin (nonalbumin) fraction. Although haptenated serum γ-globulins would be present in this fraction, it is also possible that other constituents with potential tolerogenic capacity are present (i.e., various serum proteins or cell surface membrane fragments that are trinitrophenylated). The data are consistent with the suggestion that TNBS-induced tolerance in vivo is mediated by a component of TolS that is active as a tolerogen in vitro .
Antineoplastic Therapy in Colorectal Cancer through Proteasome Inhibition (2003)

Upregulation of nuclear factor (NF)-kappaB is found in many forms of cancer. Activation of NF-kappaB in cancer cells by chemotherapy or radiation can blunt the ability of this therapy to induce cell death. Proteasome inhibitors stimulate apoptosis in part via prevention of NF-kappaB activation. We sought to determine whether constitutive NF-kappaB activity is present in human colon cancer. In addition we studied whether alterations of NF-kappaB activity with a proteasome inhibitor would prevent colon cancer cell growth and induce apoptosis. We demonstrated constitutive transcriptional activation of NF-kappaB in SW48 and SW116 colon cancer cells by luciferase and electromobility shift assays. This was confirmed by p65 immunostaining. This activity was further induced in the presence of chemotherapy. In colon cancer specimens constitutive activation of NF-kappaB was observed in the majority of tumors. Treatment with the proteasome inhibitor (MG-132) inhibited growth and also stimulated apoptosis of colon cancer cells. We conclude that inhibition of NF-kappaB activation may be a logical therapy for certain cancers. This can be done via specific approaches on molecules necessary for keeping NF-kappaB inactivated in the cytoplasm. Other potentially useful ways to promote apoptosis in cancer cells include the utilization of proteasome inhibitors. Such inhibitors are currently being evaluated in clinical trials.
Interaction of the DNA modifying proteins VirD1 and VirD2 of <i>Agrobacterium tumefaciens</i> : Analysis by subcellular localization in mammalian cells (1998)

Interaction between Agrobacterium tumefaciens and plants provides a unique example of interkingdom gene transfer. Agrobacterium, a plant pathogen, is capable to stably transform the plant cell with a segment of its own DNA called T-DNA (transferred DNA). This process depends, among others, on the specialized bacterial virulence proteins VirD1 and VirD2 that excise the T-DNA from its adjacent sequences. Subsequent to transfer to the plant cell, the virulence protein VirD2, through its nuclear localization signal (NLS), is believed to guide the T-DNA to the nucleus. The T-DNA then is integrated into the plant genome. Although both of these proteins are essential for bacterial virulence, physical interaction of them has not been analyzed so far. We studied associations between these proteins by expressing them in mammalian cells and by testing for intracellular localization and colocalization. When expressed in human cells [HeLa, human embryo kidney (HEK) 293], the VirD2 protein homogeneously distributed over the nucleoplasm. The presence of any of two NLSs, on the N and C termini of VirD2, was sufficient for its efficient nuclear localization whereas deletion of both NLSs rendered the protein cytoplasmic. However, this double NLS mutant was translocated to the nucleus in the presence of wild-type VirD2 protein, implying VirD2-VirD2 interaction. The VirD1 protein, by itself localized in the cytoplasm, moved to the nucleus when coexpressed with the VirD2 protein, suggesting VirD1-VirD2 interaction. This interaction was confirmed by coimmunoprecipitation tests. Of interest, both proteins coimported to the nucleus showed a similar, peculiar sublocalization. The data are discussed in terms of functions of the VirD proteins. In addition, coimport of proteins into nuclei is suggested as a useful system in studying individual protein-protein interactions.
Self-sustained picosecond pulse generation in a GaAlAs laser at an electrically tunable repetition rate by optoelectronic feedback (1984)

We demonstrate that applying optoelectronic feedback to a high-speed, self-pulsing semiconductor laser is an effective and practical means of generating picosecond optical pulses (∼10–20 ps) at a very high repetition rate, between 1 to 5 GHz, which can be electrically tuned. The optical pulses are very stable both on a short term basis with a frequency stability of one part in 105, and on the long term basis as a result of the absence of critical optical alignment. This laser system is potentially very useful in high-speed electro-optic signal processing, optical multiplexing, or laser ranging.
Active steering control based on piecewise affine regions (2010)

This paper shows that an active front steering control can be designed taking into account the nonlinear behaviour of the tire-road forces considering the vehicle dynamics with respect to the tire sideslip angle and by approximating the tire force characteristics by piecewise affine functions. The proposed control strategy involves the design of two control loops: the first one is a state feedback and it is designed to improve the vehicle dynamics using the pole placement techniques while the second control loop uses a PI control to ensure the tracking of constant yaw rate reference signal on the basis of the yaw rate tracking error despite constant disturbances and parameters uncertainties. Several simulations, including disturbances rejections and step references, are carried out on a standard CarSim D-Class vehicle model to explore the robustness with respect to unmodelled effects such as combined lateral and longitudinal tire forces, pitch, roll and driver dynamics. The simulations confirm that the proposed PWL control can greatly improve the vehicle stability and may be advantageous in very demanding manoeuvres in comparison with the use of the proposed controller designed for the linear region only.
Criticality assessments using polyurethane foam (2010)

Rolls-Royce has designed a package to transport and store fresh fuel assemblies and anticipates approval from the regulators for the new package design in the near future. The space between the inner and outer steel shells is filled with shaped blocks of rigid polyurethane foam, of two different densities. The criticality safety case for the fresh fuel package had to consider single packages and arrays of packages under routine, normal and accident conditions. IAEA regulatory requirements state that the criticality assessment must include investigations on the effect on the neutron multiplication factor k eff due to impacts, flooding and fire. Sensitivity studies must also be carried out to determine the effects on the k eff due to any uncertainties in the composition of the fuel and container materials. An important part of the criticality safety case is the treatment of the foam. The approach adopted to model the polyurethane foam is the subject of this paper. The following were investigated: (1) the effect on the k eff of varying the elemental composition of the foam, including the removal of hydrogen; (2) the experimental analysis of burnt foam; (3) the effect of addition of water to the foam to simulate water absorption; (4) a simple representation of crushed foam to simulate knock-back in the package; (5) extreme representations of burnt foam, such as replacing foam with solid carbon or as randomly distributed spheres of carbon to represent soot. These investigations were most informative and should be considered in any criticality assessments of transport packages containing large amounts of foam in the future.