gebhart/patrepeval huggingface dataset:
Tissue engineering: Confronting the transplantation crisis (2000)

Tissue engineering is the development of biological substitutes and/or the fostering of tissue regeneration/remodelling. It is emerging as a technology which has the potential to confront the crisis in transplantation caused by the shortage of donor tissues and organs. With the development of this technology, ther is emerging a new industry which is at the interface of biotechnology and the traditional medical implant field. For this technology and the associated industry to realize their full potential, there are core, enabling technologies that need to be developed. This is the focus of the Georgia Tech/Emory Center for the Engineering of Living Tissues, newly established in the United States, with an Engineering Research Center Award from the National Science Foundation. With the development of these core technologies, tissue engineering will evolve from an art form to a technology based on science and engineering.
Room Acoustics (2016)

Well established as a classic reference and specialised textbook, since its first publication in 1973, Heinrich Kuttruff’s Room Acoustics combines detailed coverage with a state of art presentation of the theory and practice of sound behaviour in closed spaces. This sixth edition presents several additional new sections, for instance on the reflection of a spherical wave from a wall, on finite element methods for sound field calculation and on virtual reality, as well as giving an overhaul of the standard material. Particular emphasis is given to the properties and calculation of reverberation, the most obvious acoustical feature of a room. And further key topics include the various mechanisms of sound absorption and their practical application as well as scattering by wall irregularities including pseudo-stochastic structures. Extensive space is given to of psychoacoustic insights and the quality criteria derived from them, along with new procedures for the sensory assessment of concert hall acoustics. As in earlier editions, one full and updated chapter is devoted to the design and performance of electroacoustic systems which nowadays is not just a method for sound amplification but offers many possibilities for correcting acoustic deficiencies and modifying a hall’s natural acoustics.
Benefits and pitfalls of common-bussing AC inverters (2002)

Low-cost high-performance AC inverters increasingly find application in web-transport systems that previously used line-regenerative DC drives. Common-bussing of AC inverters offers an inexpensive alternative to line-regeneration in many of these applications. This paper discusses the concept of common-bussing, suggests the types of drives that may be easily used in common-bus schemes, and presents an analysis of a critical issue, i.e., proper fuse sizing to balance durability in normal operation with fault interrupting capability. Analysis of a specific drive family is used to illustrate fuse and inductor selection parameters and techniques.
Apical Membrane Antigen 1, a Major Malaria Vaccine Candidate, Mediates the Close Attachment of Invasive Merozoites to Host Red Blood Cells (2003)

Apical membrane antigen 1 (AMA-1) of Plasmodium merozoites is established as a candidate molecule for inclusion in a human malaria vaccine and is strongly conserved in the genus. We have investigated its function in merozoite invasion by incubating Plasmodium knowlesi merozoites with red cells in the presence of a previously described rat monoclonal antibody (MAb R31C2) raised against an invasion-inhibitory epitope of P. knowlesi AMA-1 and then fixing the material for ultrastructural analysis. We have found that the random, initial, long-range (12 nm) contact between merozoites and red cells occurs normally in the presence of the antibody, showing that AMA-1 plays no part in this stage of attachment. Instead, inhibited merozoites fail to reorientate, so they do not bring their apices to bear on the red cell surface and do not make close junctional apical contact. We conclude that AMA-1 may be directly responsible for reorientation or that the molecule may initiate the junctional contact, which is then presumably dependent on Duffy binding proteins for its completion.
A High-Voltage Compatible BCD SoC-ASIC Performing Valley-Switching Control of AC-DC Power Converters Based on PFC and Flyback Cells (2006)

This paper presents an ASIC controller suitable for double-stage AC-DC power converters which employ Power Factor Correction (PFC) and Flyback topologies. The PFC cell is used as preregulator to comply with line-current harmonic standards, while the flyback converter operates in quasi-resonant/discontinuous-conduction-mode (QR/DCM) to deliver to the load a maximum output power of 120 W. The control functions of the PFC and of the flyback converters are combined in an unique SoC-ASIC solution to reduce system complexity. The ASIC implements a valley-switching control of both the PFC and the flyback cells to achieve quasi-resonant (QR) operation. The concept of "valley skipping" is also recalled by the proposed ASIC to determine the operating point in the power-frequency characteristic of the power converter. Depending on the output power requirement, the ASIC drives the flyback stage into three different states, resulting from the combination of the QR and valley-skipping modes. The PFC stage is also driven in the QR mode with valley skipping to provide the DC-DC stage with a fixed input voltage of 400 V. To evaluate the performances of the presented ASIC device, a demoboard of a 120 W PFC-flyback system has been realized and tested
Leptin—Much More Than a Satiety Signal (2000)

Much attention has focused on the effects of leptin as a central satiety agent. There is now a significant amount of evidence that leptin is active in the periphery. This review focuses on the ability of leptin to modify insulin sensitivity, tissue metabolism, stress responses, and reproductive function. Leptin's effect on several of these systems is mediated via the hypothalamic-pituitary axis. Therefore, although in vitro studies provide evidence for direct effects on specific tissues and metabolic pathways, it is essential to consider the interactions between leptin and other regulatory factors in vivo. Little is known about the regulation of peripheral receptor expression or the production of binding proteins. Both of these factors determine the bioactivity of circulating leptin and have the potential to induce a peripheral resistance to leptin, similar to the central "leptin resistance" observed in obese subjects. Future research will clarify which of the endocrine and metabolic actions of peripheral leptin are of physiological relevance and which should be considered a pharmacological manipulation.
Solid streamer noise reduction principles (2006)

Today's solid streamers are generally less sensitive to mechanical noise originating from sea swell effects and are insensitive to vibration from depth controllers (birds) and mechanical towing equipment. In addition, for a given level of sea swell, they can be towed shallower without a significant noise increase. The dominant transport mechanism for parasitic or unwanted vibration in any streamer design (whether using solid or fluid‐based buoyancy) is the axial extensional wave. If such extensional waves are permitted to generate significant pressure or stress at the locations of the hydrophone elements, then undesirable coherent noise will result. In fluid streamers, coupling between extensional waves and hydrophones occurs through the medium of bulge waves. With extremely careful mechanical design, and by forming linear arrays of individual hydrophone elements which exploit the low speed of bulge waves, fluid filled streamers may achieve acceptable mechanical noise performance. Single hydrophones in fluid streamers are always excessively noisy. In a solid buoyancy streamer the low speed bulge waves are replaced by higher speed compressional waves, thus precluding array forming as a primary means of mechanical noise reduction within the critical 3Hz to 50Hz band. However with appropriate design and materials, a high degree of noise isolation can be realised. As mechanical isolation must be achieved independently of the use of arrays, both arrays and single hydrophones in a solid streamer can be relatively quiet. One successful method of manufacturing a solid streamer encloses the hydrophone element in a relatively stiff package which resists the stress and strain normally induced by the passage of axial extensional waves. This package or Strain Isolation Module (SIM) contains acoustically transparent coupling fluid and also includes an elongated external diaphragm or diaphragms providing a high degree of turbulent noise reduction. Using this technology, improvements in mechanical noise isolation of the order of 15dB have been measured at sea. Observed improvements in field results are well predicted by simple axial wave theory.
Kinetics of Epitaxial Silicon Deposition by a Low Pressure Iodide Process (1965)

This report is primarily a study of the factors which control the vapor transport process of silicon in a modified closed tube low pressure cyclic iodide process. The kinetics of transport from the source to the substrate are examined and are found to agree with a diffusion controlled mechanism. The model is useful for estimating the deposition rate under a variety of conditions. The process is found capable of depositing silicon on silicon substrates at relatively high deposition rates. Impurity doping with this process is accomplished by incorporating the desired impurity into the source silicon.
The Reaction of Oxygen Atoms with Tetrafluoroethylene<sup>1</sup> (1965)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Reaction of Oxygen Atoms with Tetrafluoroethylene1Dennis Saunders and Julian HeicklenCite this: J. Am. Chem. Soc. 1965, 87, 10, 2088–2092Publication Date (Print):May 1, 1965Publication History Published online1 May 2002Published inissue 1 May 1965https://pubs.acs.org/doi/10.1021/ja01088a002https://doi.org/10.1021/ja01088a002research-articleACS PublicationsRequest reuse permissionsArticle Views84Altmetric-Citations27LEARN 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
XY sex reversal associated with a deletion 5' to the SRY "HMG box" in the testis-determining region. (1992)

The human testis-determining factor resides within a 35-kilobase (kb) region of the Y chromosome immediately adjacent to the pseudoautosomal boundary. A candidate gene for human sex determination (SRY) was isolated in this region. Here, we describe a study of 25 cases of XY females with pure gonadal dysgenesis for mutations on the Y chromosome short arm, including SRY. Southern blotting revealed a sex-reversed female harboring a deletion extending from approximately 8 kb from the pseudoautosomal boundary of the Y chromosome to at least 33 kb and no more than 60 kb upstream, toward the centromere. The deletion begins no more than 1.8 kb upstream from the first ATG of the SRY open reading frame present in the clone pY53.3. To our knowledge, no mutation has been described previously outside the SRY "HMG box" on the short arm of the Y chromosome, which is associated with sex reversal. Since the 5' extent of the SRY transcriptional unit has not been defined, the deletion may remove upstream exons of SRY and/or transcriptional regulatory motifs, either situation resulting in lack of testicular development. It cannot be formally excluded that the mutation removes a second locus, independent of SRY, that is critical for sex determination. Denaturant gradient gel electrophoresis analysis of the SRY open reading frame in the remaining 24 cases revealed de novo single base-pair transitions in the SRY conserved domain in 4 cases.
"call-level" and "burst-level" priorities for an effective management of multimedia services in UMTS (2002)

It is not an easy task in the UMTS environment to effectively design the transport and the management of traffic belonging to multimedia teleservices, due to the difficult communication requirements of such applications. It is proposed to contemporary use at the "transport" layer of the system several bearers, one for each traffic component of the multimedia service. Furthermore, a two-level (static and dynamic) priority mechanism is to be adopted by the higher protocol levels of the UMTS for the adaptation of call set-up, channel access, and admission control procedures to the nature of the multimedia services and to optimise the sharing of radio channel resources and the management of the reservation buffer. The results achieved demonstrate that the proposed mechanism shows a good performance especially during periods in which the system traffic load is high and reacts well to the worsening of the multimedia service quality, both in terms of information loss and synchronisation of its traffic components.
Conditionally active STAT1 and its functional role in tumor progression and invasion (2006)

1825 The signal transducer and activator of transcription STAT1 is activated in breast carcinomas and a recent microarray study by our group suggested a potential involvement of STAT1 in the onset of bone marrow micrometastasis in breast cancer patients (1). We have now conducted the first functional experiments to unravel the precise role of STAT1 in breast cancer micrometastasis. It is known that increased gene expression of the latent cytoplasmic transcription factor STAT1 does not automatically lead to a transcriptional activation of target genes. STAT1 must be phosphorylated which triggers the dimerisation of STAT1 monomers and enables then the translocation of the homodimers into the nucleus to initiate DNA binding and gene expression. Therefore we used conditionally active STAT1 by fusing STAT1 with the ligand binding domain (LBD) of the oestrogen receptor (ER). The resulting STAT1-ERLBD chimeras were transfected into the oestrogen receptor- negative, low invasive mammary carcinoma cell line MDA-MB468. Western Blot analyses and immunocytochemical stainings with an ERLBD specific antibody confirmed the expression of the STAT1-ERLBD chimera. 10-5 to 10-8M oestrogen stimulation in the STAT1-ERLBD expressing MDA-MB468 cells as measured by luciferase reporter assays using the STAT1-inducible reporter GAS-luc resulted in a 5-8 fold activation of the reporter. Using this inducible system active STAT1 was associated with a reduced proliferation rate but had no influence on the invasive properties of the analysed breast cancer cells, as shown by in vitro invasion assays (Boyden Chamber assays). In conclusion, the established experimental model system allows the in-depth investigation of the role of STAT1 activation in breast cancer cells. STAT1 appears to be a negative regulator of cell proliferation and might therefore be a candidate for an inducer of tumor cell dormancy, a hallmark of micrometastatic cancer cells (2). References 1. Woelfle, U., Cloos, J., Sauter, G., Riethdorf, L., Janicke, F., van Diest, P., Brakenhoff, R., and Pantel, K. Molecular signature associated with bone marrow micrometastasis in human breast cancer. Cancer Res, 63: 5679-5684, 2003. 2. Pantel, K. and Brakenhoff, R. H. Dissecting the metastatic cascade. Nat Rev Cancer, 4: 448-456, 2004.
Study of Magnetic Losses at Low Flux Densities in 35 Permalloy Sheet (1937)

Energy losses in ferromagnetic materials subject to alternating fields have long been considered as due solely to hysteresis and eddy currents. However, at the low flux densities encountered in certain communication apparatus, a further loss is observed which has been variously termed ``residual,'' ``magnetic viscosity,'' or ``square law hysteresis.'' The search for an explanation of this loss has led to precise measurements of hysteresis loops with a vacuum ballistic galvanometer, and of a.c. losses with inductance bridges. From these results, it appears that that part of the a.c. effective resistance of a coil on a ferromagnetic core which is proportional to the coil current is strictly identified with the hysteresis loop area as measured by a ballistic galvanometer, or as indicated by harmonic generation in the coil. The hysteresis loop can now be constructed in detail as to size and skewness on the basis of a.c. bridge measurements. This conclusion was reached previously on a compressed iron powder core, and is now confirmed on an annealed laminated 35 permalloy core. Observed eddy current losses for this core exceed those calculated from classical theory by 20 percent. This excess is ascribed to the presence of low permeability surface layers on the sheet magnetic material. The a.c. residual loss per cycle (nominally independent of frequency, like hysteresis) is not observed by ballistic galvanometer measurements, although it indicates an energy loss some eight times the hysteresis loss for the smallest loop measured (Bm = 1.3 gauss). Analysis of the residual loss shows that it increases with frequency up to about 500 cycles, and remains constant at higher frequencies (to 10,000 cycles per second). Concurrently with the increase of residual loss, the permeability of the alloy is observed to decline with increasing frequency about 1 percent below the value predicted from eddy current shielding. This effect is most noticeable at frequencies below 1000 cycles.
Pharmacological profile of valsartan, a non-peptide angiotensin II type 1 receptor antagonist. 4th communication: improvement of heart failure of rats with myocardial infarction by valasartan. (1997)

The hemodynamic effects of valsartan ((S)-N-valeryl-N-¿[2'-(1H-tetrazol-5-yl)bipheneoyl-4-yl]meth yl¿valine, CAS 137862-53-4, CGP 48933), a new angiotensin II type 1 receptor antagonist, on rats with myocardial infarction induced by coronary artery ligation was examined. Four weeks after ligation, mean blood pressure, left ventricular pressure and cardiac output decreased, while left ventricular end-diastolic pressure increased in control rats. Left ventricular end-diastolic pressure significantly decreased in rats treated with valsartan at 30 mg/kg/d p.o. for 4 weeks. Total systemic resistance remarkably decreased in those with enalapril 3 mg/kg/d p.o. and valsartan 30 mg/kg/d p.o. Valsartan and enalaprilat did not affect cardiac functions of isolated intact rat hearts before and after ischemia in Langendorff apparatus. In addition to hemodynamic effects observed in vivo, valsartan at 30 mg/kg p.o. significantly inhibited left ventricular hypertrophy. Valsartan would thus appear to be clinically useful for treating heart failure following myocardial infarction.
Heart Rate Variability (1993)

Heart rate variability analysis is easily applicable in adult medicine, but physiologic influences such as age must be considered. The most important application is the surveillance of postinfarction and diabetic patients to prevent sudden cardiac death. With heart rate variability analysis, individual therapy adjustments to achieve the most favorable sympathetic-parasympathetic balance might be possible in the future.
Cardiovascular autophagy (2013)

Despite recent scientific and technological advances, cardiovascular disease remains the leading cause of morbidity and mortality worldwide. Autophagy, an evolutionarily ancient response to cellular stress, has been implicated in the pathogenesis of a wide range of heart pathologies. However, the precise role of autophagy in these contexts remains obscure owing to its multifarious actions. Here, we review recently derived insights regarding the role of autophagy in multiple manifestations of cardiac plasticity and disease.
Rapid Access for the Synthesis of 1‐N‐Methyl‐spiro[2.3′]oxindole‐spiro[3.7″] (3″‐Aryl)‐5″‐methyl‐3″,3a″,4″,5″,6″,7″‐hexahydro‐2H‐pyrazolo[4,3‐<i>c</i>]pyridine‐4‐aryl‐pyrrolidines Through Sequential 1,3‐Dipolar Cycloaddition and Annulation (2006)

Abstract The 1,3‐dipolar cycloaddition of an azomethine ylide, generated from isatin and sarcosine by a decarboxylative route with various p‐substituted 3,5 bis(aryl methylidene)N‐methyl‐4‐piperidinones in refluxing methanol, proceeded regioselectively to give novel dispiroheterocycles. The product on subsequent annulation with hydrazine hydrate afforded 1‐N‐methyl‐spiro[2.3′]oxindole‐spiro[3.7″](3″‐aryl)‐5″‐methyl‐3″,3a″,4″,5″,6″,7″‐hexahydro‐2H‐pyrazolo[4,3‐c]pyridine‐4‐aryl‐pyrrolidines in good yield. Keywords: 3,5‐Bis(aryl methylidene)N‐methyl‐4‐piperidinones1,3‐dipolar cycloaddition
The localization problem for mobile robots (2002)

A fundamental task for an autonomous mobile robot is that of localization-determining its location in a known environment. This problem arises in settings that range from the computer analysis of aerial photographs to the design of autonomous Mars rovers. L. Guibas et al. ((1992) have given geometric algorithms for the problem of enumerating locations for a robot consistent with a given view of the environment. We provide an on-line algorithm for a robot to move within its environment so as to uniquely determine its location. The algorithm improves asymptotically on strategies based purely on the "spiral search" technique of R. Baeza-Yates et al. (1993); an interesting feature of our approach is the way in which the robot is able to identify "critical directions" in the environment which allow it to perform late stages of the search more efficiently.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Temperature dependence of the growth rate for nanocrystalline diamond films deposited from an Ar/CH4 microwave plasma (1998)

We have investigated the effect of substrate temperature on the growth rate and properties of nanocrystalline diamond thin films prepared by microwave plasma-assisted chemical vapor deposition on (100) Si from a 1% methane (CH4) precursor in argon (Ar). In previous work we have shown that the carbon dimer C2 is the dominant growth species for this CH4/Ar system without the addition of molecular hydrogen. In the present work, the apparent activation energy for this growth process from C2 was determined from a standard Arrhenius-type analysis of the growth rate data for substrate temperatures between 500 and 900 °C. The measured value of 5.85±0.438 kcal/mol (0.254±0.019 eV/atom) is shown to be in close agreement with the results of recent modeling studies of the energetics of C2 addition to the diamond (110)–(1×1):H surface. These results have important implications for low-temperature diamond coating of nonrefractory materials such as glasses.