gebhart/patrepeval huggingface dataset:
Deep reactive ion etching of silicon using an aluminum etching mask (2003)

A method for fast and efficient deep anisotropic etching of bulk silicon, using a parallel capacitively coupled plasma is presented. The effect of the masking materials and RIE conditions are discussed. Based on the experimental results, a 1000 angstrom thick Al film sufficiently protects the unexposed substrate while allowing the etching of a 350mm deep hole with an area of 3x3mm2 when etching with SF<sub>6</sub> /CHF<sub>3</sub>/O<sub>2</sub> plasma. A 2000mm long and 100mm wide (with layers of Al/SiO2/Si and thicknesses of 0.1mm/2.2mm/40mm respectively) cantilever is also achieved. A silicon etch rate up to 2.2 mm/min has be obtained and an anisotropy of A= 0.5 (A=1-V/H, where V=horizontal undercut, H=etch depth) has been observed. The technique was developed mainly for bulk micromachining of silicon or composite silicon cantilever structures.
Chemical modification of erythromycins. II. Synthesis and antibacterial activity of O-alkyl derivatives of erythromycin A. (1990)

A series of O-alkyl erythromycin A derivatives have been synthesized and their antibacterial activities compared with those of erythromycin A (1) and 6-O-methylerythromycin A (3). Methylation of the hydroxyl groups of erythromycin A analogue proceeded stepwise by the two main pathways beginning at the C-6 and C-11 positions, individually. O-Alkylation, other than methylation, took place at the C-11 hydroxyl group exclusively. Among O-alkyl derivatives, 6,12-di-O-methylerythromycin A (5) showed comparable in vitro antibacterial activity to those of 1 and 3. 11-O-Methylerythromycin A (8) was slightly less active than 1. O-Methylation at the C-4" position resulted in a decrease of antibacterial activity.
Cutting Edge: Induced Expression of a RhoA-Specific Guanine Nucleotide Exchange Factor, p190RhoGEF, Following CD40 Stimulation and WEHI 231 B Cell Activation (2003)

Stimulation of the B cell surface receptor CD40 induces transcriptional activation and protein expression. To determine which proteins are required for the CD40-mediated B cell activation, we performed a two-dimensional gel electrophoresis of the WEHI 231 B cell lysates. We report in this study the identification of one protein in which the expression was remarkably induced following CD40 stimulation. It was the p190 Rho guanine nucleotide exchange factor (GEF), p190RhoGEF, a recently identified GEF that is specific for RhoA. Overexpression of either p190RhoGEF or RhoA (Q63L), a constitutively active form of RhoA, mimics the effects of CD40 stimulation, such as changes in cellular structure and NF-kappaB activation. These p190RhoGEF overexpression effects are abrogated when coexpressed with a dominant negative form of RhoA (T19N). We also provide evidence for the CD40-mediated cellular changes that are abrogated in cells that are overexpressed with the dominant negative form of either p190RhoGEF (Y1003A) or RhoA (T19N).
A perceptual-defensive-recuperative model of fear and pain (1980)

Abstract A model of fear and pain is presented in which the two are assumed to activate totally different classes of behavior. Fear, produced by stimuli that are associated with painful events, results in defensive behavior and the inhibition of pain and pain-related behaviors. On the other hand, pain, produced by injurious stimulation, motivates recuperative behaviors that promote healing. In this model injurious stimulation, on the one hand, and the expectation of injurious stimulation, on the other hand, activate entirely different motivational systems which serve entirely different functions. The fear motivation system activates defensive behavior, such as freezing and flight from a frightening situation, and its function is to defend the animal against natural dangers, such as predation. A further effect of fear motivation is to organize the perception of environmental events so as to facilitate the perception of danger and safety. The pain motivation system activates recuperative behaviors, including resting and body-care responses, and its function is to promote the animal's recovery from injury. Pain motivation also selectively facilitates the perception of nociceptive stimulation. Since the two kinds of motivation serve different and competitive functions, it might be expected that they would interact through some kind of mutual inhibition. Recent research is described which indicates that this is the case. The most important connection is the inhibition of pain by fear; fear has the top priority. This inhibition appears to be mediated by an endogenous analgesic mechanism involving the endorphins. The model assumes that fear triggers the endorphin mechanism, thereby inhibiting pain motivation and recuperative behaviors that might compete with effective defensive behavior.
Structural Evolution of Hexadecanethiol Monolayers on Gold during Assembly:  Substrate and Concentration Dependence of Monolayer Structure and Crystallinity (1998)

The structures of hexadecanethiol (HDT) self-assembled monolayers (SAM) on gold assembled for up to 11 days from ethanolic HDT solutions are reported. Gold|HDT films were periodically removed from 0.001, 0.1, 1, or 10 mM HDT solution and analyzed by Fourier transform infrared external reflection spectroscopy (FTIR-ERS). FTIR-ERS data provide evidence for an ongoing increase in SAM crystallinity and, in some cases, a decrease in average chain tilt angle with respect to the surface normal during this long assembly time. SAM crystallinity, judged by line shape and position, increased more rapidly for more concentrated HDT solutions but appears to converge on the same final value independent of HDT concentration in the range of 10-6 to 10-2 M. Computer-optimized fits to the ensemble of C−H stretching bands between 2800 and 3000 cm-1 made on ∼50 different SAMs which were prepared under a wide range of conditions return surprisingly consistent average tilt and twist angles. For Au on Cr-primed glass the absolute values of the average cant and twist angles were 20 ± 2° and 49 ± 3°, respectively, and for Au on HF-etched Si〈111〉 they were 22 ± 2° and 51 ± 1°, respectively. A clear trend in SAM cant angles, decreasing with increasing time, is observed for the glass|Cr|Au|HDT system. Two structural models were compared: one in which all chains are identical and one in which alternating alkanethiol chains have orthogonal backbone planes.
Application of Sensor Networks in Agriculture (2012)

Sensor networks offer a powerful combination of distributed sensing, computing and communication. The distinguishing traits of sensor networks have a direct impact on the hardware design of the nodes at various levels: power source, processor, communication hardware, sensor nodes and actuation components. Sensor networks are also widely applied in habitat monitoring and agriculture research. An integrated network of sensors combining on the ground sensors monitoring soil moisture levels, humidity, temperature, plant growth, ground water level, disease identification together with Global positioning system facilities and long term field monitoring to absorb the variations in the agricultural field will enable the determination of risk levels in targeted regions as well as valuable information on agricultural development. The overall goal of the research and development effort described in this work is to devise an integrated system in the form of plant growth monitoring and control system comprising a distributed network of sensors for sensing the plant growth activity, drip water irrigation, temperature sensing, ground water monitoring and environmental conditions to improve the productivity in agriculture.
Sphincteroplasty for anal incontinence (2014)

Sphincteroplasty (SP) is the operation most frequently performed in patients suffering from moderate-to-severe anal incontinence (AI) who do not respond to conservative treatment. Other costly surgeries, such as artificial bowel sphincter (ABS) and electro-stimulated graciloplasty, have been more or less abandoned due to their high morbidity rate. Minimally invasive procedures are widely used, such as sacral neuromodulation and injection of bulking agents, but both are costly and the latter may cure only mild incontinence. The early outcome of SP is usually good if the sphincters are not markedly denervated, but its effect diminishes over time. SP is more often performed for post-traumatic than for idiopathic AI. It may also be associated to the Altemeier procedure, aimed at reducing the recurrence rate of rectal prolapse, and may be useful when AI is due either to injury to the sphincter, or to a narrowed rectum following the procedure for prolapse and haemorrhoids (PPH) and stapled transanal rectal resection (STARR). The outcome of SP is likely to be improved with biological meshes and post-operative pelvic floor rehabilitation. SP is more effective in males than in multiparous women, whose sphincters are often denervated, and its post-operative morbidity is low. In conclusion, SP, being both low-cost and safe, remains a good option in the treatment of selected patients with AI.
Superior feature-set ranking for small samples using bolstered error estimation (2004)

This paper examines the feature-ranking performance of several kinds of error estimators: resubstitution, cross-validation, bootstrap and bolstered error estimation. It does so for three classification rules: linear discriminant analysis, three-nearest-neighbor classification and classification trees. Two measures of performance are considered. One counts the number of the truly best feature sets appearing among the best feature sets discovered by the error estimator and the other computes the mean absolute error between the top ranks of the truly best feature sets and their ranks as given by the error estimator. Our results indicate that bolstering is superior to bootstrap, and bootstrap is better than cross-validation, for discovering top-performing feature sets for classification when using small samples. A key issue is that bolstered error estimation is tens of times faster than bootstrap, and faster than cross-validation, and is therefore feasible for feature-set ranking when the number of feature sets is extremely large.
Studies on the C11H8N2OS Degradation Product of Gliotoxin1 (1951)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStudies on the C11H8N2OS Degradation Product of Gliotoxin1James D. Dutcher and Anders KjaerCite this: J. Am. Chem. Soc. 1951, 73, 9, 4139–4141Publication Date (Print):September 1, 1951Publication History Published online1 May 2002Published inissue 1 September 1951https://pubs.acs.org/doi/10.1021/ja01153a026https://doi.org/10.1021/ja01153a026research-articleACS PublicationsRequest reuse permissionsArticle Views141Altmetric-Citations9LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
Asymmetric Total Synthesis of Phosphatidylinositol 3-Phosphate and 4-Phosphate Derivatives (1998)

New asymmetric syntheses of phosphatidylinositol 3-phosphate (PtdIns(3)P) and phosphatidylinositol 4-phosphate (PtdIns(4)P) derivatives are described. Key intermediates were used to prepare diacylglyceryl moieties with dibutyryl, dioctanoyl, and dihexadecanoyl chains. In addition, a modified route provided PtdIns(3)P and PtdIns(4)P triesters with P-1-linked aminopropyl groups for preparation of affinity probes. The synthesis of the inosityl precursor employed a dibutyltin oxide-mediated p-methoxybenzyl (PMB) etherification to give either the 2-PMB- or the 3-PMB-protected glucopyranosides. The Ferrier rearrangement was used to convert suitably protected glucose derivatives to enantiomerically pure, differentially protected d-myo-inositol key intermediates. A versatile phosphoramidite reagent was employed to allow synthesis of PtdInsPn derivatives with diacylglyceryl moieties of different chain lengths.
Implication of collagen type I-induced membrane-type 1-matrix metalloproteinase expression and matrix metalloproteinase-2 activation in the metastatic progression of breast carcinoma. (1997)

We have previously demonstrated that fibroblasts and invasive human breast carcinoma (HBC) cells specifically activate matrix metalloproteinase-2 (MMP-2) when cultured on 3-dimensional gels of type I collagen but not a range of other substrates. We show here the constitutive expression of membrane-type 1 (MT1)-MMP in both fibroblasts, and invasive HBC cell lines, that have fibroblastic attributes presumably acquired through an epithelial-to-mesenchymal transition (EMT). Treatment with collagen type I increased the steady-state MT1-MMP mRNA levels in these cells but did not induce either MT1-MMP expression or MMP-2 activation in noninvasive breast carcinoma cell lines, which retain epithelial features. Basal MT3-MMP mRNA expression had a pattern similar to that of MT1-MMP but was not up-regulated by collagen. MT4-MMP mRNA was seen in both invasive and noninvasive HBC cell lines and was also not collagen-regulated, and MT2-MMP mRNA was not detected in any of the HBC cell lines tested. These data support a role for MT1-MMP in the collagen-induced MMP-2-activation seen in these cells. In situ hybridization analysis of archival breast cancer specimens revealed a close parallel in expression of both collagen type I and MT1-MMP mRNA in peritumoral fibroblasts, which was correlated with aggressiveness of the lesion. Relatively high levels of expression of both mRNA species were seen in fibroblasts close to invasive tumor nests and, although only focally, in certain areas close to preinvasive tumors. These foci may represent hot spots for local degradation and invasive progression. Collectively, these results implicate MT1-MMP in collagen-stimulated MMP-2 activation and suggest that this mechanism may be employed in vivo by both tumor-associated fibroblasts and EMT-derived carcinoma cells to facilitate increased invasion and/or metastasis.
The Dual Role of Cellular Senescence in Developing Tumors and Their Response to Cancer Therapy (2017)

Cellular senescence describes an irreversible growth arrest characterized by distinct morphology, gene expression pattern, and secretory phenotype. The final or intermediate stages of senescence can be reached by different genetic mechanisms and in answer to different external and internal stresses. It has been maintained in the literature but never proven by clearcut experiments that the induction of senescence serves the evolutionary purpose of protecting the individual from development and growth of cancers. This hypothesis was recently scrutinized by new experiments and found to be partly true, but part of the gene activities now known to happen in senescence are also needed for cancer growth, leading to the view that senescence is a double-edged sword in cancer development. In current cancer therapy, cellular senescence is, on the one hand, intended to occur in tumor cells, as thereby the therapeutic outcome is improved, but might, on the other hand, also be induced unintentionally in non-tumor cells, causing inflammation, secondary tumors, and cancer relapse. Importantly, organismic aging leads to accumulation of senescent cells in tissues and organs of aged individuals. Senescent cells can occur transiently, e.g., during embryogenesis or during wound healing, with beneficial effects on tissue homeostasis and regeneration or accumulate chronically in tissues, which detrimentally affects the microenvironment by de- or transdifferentiation of senescent cells and their neighboring stromal cells, loss of tissue specific functionality, and induction of the senescence-associated secretory phenotype, an increased secretory profile consisting of pro-inflammatory and tissue remodeling factors. These factors shape their surroundings toward a pro-carcinogenic microenvironment, which fuels the development of aging-associated cancers together with the accumulation of mutations over time. We are presenting an overview of well-documented stress situations and signals, which induce senescence. Among them, oncogene-induced senescence and stress-induced premature senescence are prominent. New findings about the role of senescence in tumor biology are critically reviewed with respect to new suggestions for cancer therapy leveraging genetic and pharmacological methods to prevent senescence or to selectively kill senescent cells in tumors.
A multiresolution spline with application to image mosaics (1983)

We define a multiresolution spline technique for combining two or more images into a larger image mosaic. In this procedure, the images to be splined are first decomposed into a set of band-pass filtered component images. Next, the component images in each spatial frequency band are assembled into a corresponding band-pass mosaic. In this step, component images are joined using a weighted average within a transition zone which is proportional in size to the wave lengths represented in the band. Finally, these band-pass mosaic images are summed to obtain the desired image mosaic. In this way, the spline is matched to the scale of features within the images themselves. When coarse features occur near borders, these are blended gradually over a relatively large distance without blurring or otherwise degrading finer image details in the neighborhood of the border.
Intratumoral delivery of inactivated modified vaccinia virus Ankara (iMVA) induces systemic antitumor immunity via STING and Batf3-dependent dendritic cells (2017)

Advanced cancers remain a therapeutic challenge despite recent progress in targeted therapy and immunotherapy. Novel approaches are needed to alter the tumor immunosuppressive microenvironment and to facilitate the recognition of tumor antigens that leads to antitumor immunity. Poxviruses, such as modified vaccinia virus Ankara (MVA), have potential as immunotherapeutic agents. We show that infection of conventional dendritic cells (DCs) with heat- or ultraviolet-inactivated MVA leads to higher levels of interferon induction than MVA alone through the cGAS (cyclic guanosine monophosphate-adenosine monophosphate synthase)-STING cytosolic DNA-sensing pathway. Intratumoral injection of inactivated MVA (iMVA) was effective and generated adaptive antitumor immunity in murine melanoma and colon cancer models. iMVA-induced antitumor therapy was less effective in STING- or Batf3-deficient mice than in wild-type mice, indicating that both cytosolic DNA sensing and Batf3-dependent CD103<sup>+</sup>/CD8α<sup>+</sup> DCs are essential for iMVA immunotherapy. The combination of intratumoral delivery of iMVA and systemic delivery of immune checkpoint blockade generated synergistic antitumor effects in bilateral tumor implantation models as well as in a unilateral large established tumor model. Our results suggest that inactivated vaccinia virus could be used as an immunotherapeutic agent for human cancers.
c-Myc promotes differentiation of human epidermal stem cells (1997)

The epidermis contains two types of proliferative keratinocyte: stem cells, with unlimited self-renewal capacity, and transit amplifying cells, those daughters of stem cells that are destined to withdraw from the cell cycle and terminally differentiate after a few rounds of division. In a search for factors that regulate exit from the stem cell compartment, we constitutively expressed c-Myc in primary human keratinocytes by use of wild-type and steroid-activatable constructs. In contrast to its role in other cell types, activation of c-Myc in keratinocytes caused a progressive reduction in growth rate, without inducing apoptosis, and a marked stimulation of terminal differentiation. Keratinocytes can be enriched for stem or transit amplifying cells on the basis of beta1 integrin expression and by use of this method to fractionate cells prior to c-Myc activation, we found that c-Myc acted selectively on stem cells, driving them into the transit amplifying compartment. As a result, activation of c-Myc in epidermis reconstituted on a dermal equivalent led to premature execution of the differentiation program. The transcriptional regulatory domain of c-Myc was required for these effects because a deletion within that domain acted as a dominant-negative mutation. Our results reveal a novel biological role for c-Myc and provide new insights into the mechanism regulating epidermal stem cell fate.
Modified Fabrication Techniques Lead to Improved Centrifugal Blood Pump Performance (1994)

The authors are developing an implantable centrifugal blood pump for short- and medium-term (1-6 months) left ventricular assist. They hypothesized that the application of result dependent modifications to this pump would lead to overall improved performance in long-term implantation studies. Essential requirements for pump operation, such as durability and resistance to clot formation, have been achieved through specialized fabrication techniques. The antithrombogenic character of the pump has been improved through coating at the cannula-housing interfaces and the baffle seal, and through changing the impeller blade material from polysulfone to pyrolytic carbon. The electronic components of the pump have been sealed for implantable use through specialized processes of dipping and potting, and the surfaces of the internal pump components have been treated to increase durability. The device has demonstrated efficacy in five chronic sheep implantation studies of 14, 10, 28, 35, and 154 day duration. Post mortem findings from the 14 day experiment showed stable fibrin entangled around the impeller shaft and blades. After pump modification, autopsy findings of the 10 day study showed no evidence of clot. Additionally, the results of the 28 day experiment showed only a small (2.0 mm) ring of fibrin at the shaft-seal interface. In the 35 and 154 day experiments, redesign of the stators have resulted in improved motor corrosion resistance. The 35 day study showed a small, 0.5 mm wide fibrin deposit at the lip seal, but no motor failure. In the 154 day experiment, the motor failed because of stator fluid corrosion, while the explanted pump was devoid of thrombus. Based on these findings, the authors believe that these pump refinements have contributed significantly to improvements in durability and resistance to clot formation.