gebhart/patrepeval huggingface dataset:
Hybrid time/frequency domain compensator for RF impairments in OFDM systems (2011)

I/Q signal processing based communication systems suffer from analog front-end (FE) imperfections such as in-phase and quadrature-phase (I/Q) imbalance and carrier frequency offset (CFO). These impairments are commonly encountered in all practical implementations, and severely degrade the obtainable link performance. Moreover, orthogonal frequency division multiplexing (OFDM)-based systems are particularly sensitive to radio frequency (RF) impairments. In this paper, we analyze the impact of transmitter and receiver I/Q imbalance together with channel distortion and CFO error on an ideal transmit signal, and propose low-complexity DSP algorithms and compensation structure for coping with such imperfections. Based on our proposed estimation/compensation structure, we are able to decouple the impairments and process them individually with rather low-complexity. More specifically, we first apply a blind algorithm for receiver I/Q imbalance compensation, followed by an efficient time domain CFO estimator and compensator. The transmitter I/Q imbalance and channel are then equalized jointly, in the frequency domain, with maximum-likelihood (ML) or zero-forcing (ZF) schemes, respectively. The applied algorithms are either blind working without aid of any training symbol or use only one OFDM symbol for impairments estimation, providing an efficient alternative solution with reduced complexity. The computer simulation results indicate a close to ideal performance of ZF scheme, and suggest that additional performance improvement due to frequency diversity can be obtained when ML estimation technique is employed.
microRNA-155 regulates angiotensin II type 1 receptor expression in umbilical vein endothelial cells from severely pre-eclamptic pregnant women (2011)

Angiotensin II is critical in pre-eclampsia pathogenesis. In addition, microRNA-155 regulates angiotensin II type 1 receptor expression. We have explored the function of microRNA-155 in pre-eclamptic pregnant women. Human umbilical vein endothelial cells were isolated and cultured from healthy puerperant women and pre-eclampsia patients. The cells were transfected with a mature microRNA-155 plasmid. The effect of microRNA-155 was assessed by Northern blotting, in situ hybridization, quantitative real-time PCR, immunofluorescent staining and Western blotting. In addition, activation of extracellular signal-regulated kinase 1/2 was assessed by co-immunoprecipitation and Western blotting. Severely pre-eclamptic pregnant women expressed less mature miR-155 compared to healthy pregnant women. In addition, angiotensin II type 1 receptor expression decreased substantially in healthy cells and miR-155-transfected cells compared to miR-155-mutant-transfected cells and cells from pre-eclamptic patients. Mature miR-155 reduced angiotensin II-induced extracellular signal-regulated kinase 1/2 activation. In conclusion, endogenous mature miR-155 expression may be an important contributor to the pathogenesis of severe pre-eclampsia.
Suppression of inflammation in ischemic and hemorrhagic stroke: therapeutic options (2009)

Inhibiting inflammation following both ischemic and hemorrhagic stroke remains a promising approach. More sophisticated therapies, with pleiotropic beneficial effects, and more sophisticated targeting of potential recipients, will increase the likelihood of successful clinical translation.
Genetic Control of Biosynthesis and Transport of Riboflavin and Flavin Nucleotides and Construction of Robust Biotechnological Producers (2011)

Riboflavin [7,8-dimethyl-10-(1'-d-ribityl)isoalloxazine, vitamin B₂] is an obligatory component of human and animal diets, as it serves as the precursor of flavin coenzymes, flavin mononucleotide, and flavin adenine dinucleotide, which are involved in oxidative metabolism and other processes. Commercially produced riboflavin is used in agriculture, medicine, and the food industry. Riboflavin synthesis starts from GTP and ribulose-5-phosphate and proceeds through pyrimidine and pteridine intermediates. Flavin nucleotides are synthesized in two consecutive reactions from riboflavin. Some microorganisms and all animal cells are capable of riboflavin uptake, whereas many microorganisms have distinct systems for riboflavin excretion to the medium. Regulation of riboflavin synthesis in bacteria occurs by repression at the transcriptional level by flavin mononucleotide, which binds to nascent noncoding mRNA and blocks further transcription (named the riboswitch). In flavinogenic molds, riboflavin overproduction starts at the stationary phase and is accompanied by derepression of enzymes involved in riboflavin synthesis, sporulation, and mycelial lysis. In flavinogenic yeasts, transcriptional repression of riboflavin synthesis is exerted by iron ions and not by flavins. The putative transcription factor encoded by SEF1 is somehow involved in this regulation. Most commercial riboflavin is currently produced or was produced earlier by microbial synthesis using special selected strains of Bacillus subtilis, Ashbya gossypii, and Candida famata. Whereas earlier RF overproducers were isolated by classical selection, current producers of riboflavin and flavin nucleotides have been developed using modern approaches of metabolic engineering that involve overexpression of structural and regulatory genes of the RF biosynthetic pathway as well as genes involved in the overproduction of the purine precursor of riboflavin, GTP.
<scp>TDP</scp> ‐1, the <i> <scp>C</scp> aenorhabditis elegans </i> ortholog of <scp>TDP</scp> ‐43, limits the accumulation of double‐stranded <scp>RNA</scp> (2014)

Caenorhabditis elegans mutants deleted for TDP-1, an ortholog of the neurodegeneration-associated RNA-binding protein TDP-43, display only mild phenotypes. Nevertheless, transcriptome sequencing revealed that many RNAs were altered in accumulation and/or processing in the mutant. Analysis of these transcriptional abnormalities demonstrates that a primary function of TDP-1 is to limit formation or stability of double-stranded RNA. Specifically, we found that deletion of tdp-1: (1) preferentially alters the accumulation of RNAs with inherent double-stranded structure (dsRNA); (2) increases the accumulation of nuclear dsRNA foci; (3) enhances the frequency of adenosine-to-inosine RNA editing; and (4) dramatically increases the amount of transcripts immunoprecipitable with a dsRNA-specific antibody, including intronic sequences, RNAs with antisense overlap to another transcript, and transposons. We also show that TDP-43 knockdown in human cells results in accumulation of dsRNA, indicating that suppression of dsRNA is a conserved function of TDP-43 in mammals. Altered accumulation of structured RNA may account for some of the previously described molecular phenotypes (e.g., altered splicing) resulting from reduction of TDP-43 function.
Two-Week Administration of Tempol Attenuates Both Hypertension and Renal Excretion of 8-Iso Prostaglandin F <sub>2α</sub> (1999)

8-Iso prostaglandin F2alpha (8-ISO) is formed nonenzymatically from the attack of superoxide radical on arachidonic acid. Therefore, 8-ISO is a marker of oxidative stress in vivo. We have recently shown that short-term administration of the membrane-permeable, metal-independent superoxide dismutase mimetic tempol (4-hydroxy-2, 2, 6, 6-tetramethyl piperidinoxyl) normalizes blood pressure in spontaneously hypertensive rats (SHR). The present study was designed to test whether prolonged administration of tempol ameliorates oxidative stress and hypertension in SHR. In control SHR (n=8), mean arterial pressure and heart rate were increased and renal blood flow and glomerular filtration rate were reduced compared with control Wistar-Kyoto rats (WKY) (n=7). Twenty-four-hour renal excretion of 8-ISO was significantly increased in SHR compared with WKY. Two weeks of tempol administration in the drinking water (1 mmol/L) to SHR (n=8) decreased mean arterial pressure by 18% (162+/-8 to 134+/-6 mm Hg, P<0.05), increased glomerular filtration rate by 17% (1.6+/-0.2 to 1. 9+/-0.3 mL/min), and decreased renal excretion of 8-ISO by 39% (9. 8+/-0.7 to 6.0+/-0.7 ng/24 hours, P<0.05). In contrast, tempol administration to WKY (n=6) had no significant effect on mean arterial pressure (115+/-5 versus 118+/-8 mm Hg), glomerular filtration rate (3.0+/-0.4 versus 2.5+/-0.5 mL/min), or renal excretion of 8-ISO (7.9+/-0.4 versus 6.8+/-0.7 ng/24 hours). In conclusion, the SHR is a model of hypertension and renal vasoconstriction associated with oxidative stress. Because long-term administration of a superoxide scavenger reduces blood pressure and oxidative stress in vivo, this study suggests a role for oxygen radicals in the maintenance of hypertension in SHR.
Modeling and Simulation of New Encoding Schemes for High-Speed UHF RFID Communication (2015)

In this paper, we present novel high-speed transmission schemes for high-speed ultra-high frequency (UHF) radio-frequency identification communication. For high-speed communication, tags communicate with a reader using a high-speed Miller (HS-Miller) encoding and multiple antennas, and a reader communicates with tags using extended pulse-interval encoding (E-PIE). E-PIE can provide up to a two-fold faster data rate than conventional pulse-interval encoding. Using HS-Miller encoding and orthogonal multiplexing techniques, tags can achieve a two- to three-fold faster data rate than Miller encoding without degrading the demodulation performance at a reader. To verify the proposed transmission scheme, the MATLAB/Simulink model for high-speed backscatter based on an HS-Miller modulated subcarrier has been designed and simulated. The simulation results show that the proposed transmission scheme can achieve more than a 3 dB higher BER performance in comparison to a Miller modulated subcarrier.
GPS Signal Channel Modeling and Verification (2017)

Global Positioning System (GPS) is a technology that is used not only for military purposes but also for general positioning in civilian applications. It is often used in applications of Internet of Things (IoT), which have gained popularity in recent years, for example, tracking the daily activities of elderly people, and monitoring vital signs etc. The GPS signal which is extremely weak is affected by several types of errors in the course of its propagation. This situation becomes much worse particularly when the GPS receiver is located in dense urban areas where multipath effect is strongly pronounced. The received signal strength of a GPS satellite at a given location can be predicted by analyzing the propagation characteristics of the channel with an appropriate propagation model. In this paper, we propose a simple MATLAB model to estimate the received signal strength of a GPS signal in varying urban environment based on experimental measurements of the propagation characteristics of GPS signal taken in the city of Izmir, Turkey.
Use of the Round Window Microcatheter in the Treatment of Meniere's Disease (2001)

Results of this study on this group of patients indicate that vertigo can be controlled in the long term using microdose gentamicin without a significant reduction in cochlear or vestibular function in most of the patients in our series. Our results are compared with the published literature examining transtympanic injection. In addition, the underlying science supporting this type of treatment is examined.
Thermoregulatory sudomotor dysfunction and diabetic neuropathy develop in parallel in at‐risk feet (2008)

Early deterioration of small sympathetic fibres could not be quantified accurately by the clinical, somatic and autonomic tests. Assessing skin integrity and sudomotor function in at-risk individuals identifies early peripheral sympathetic neuropathy, even if the patients have no overt clinical symptoms.
In vitro activity of gatifloxacin alone and in combination with cefepime, meropenem, piperacillin and gentamicin against multidrug-resistant organisms (2003)

Gatifloxacin was synergic with the beta-lactams piperacillin, cefepime and meropenem, and with gentamicin against some drug-resistant pathogens. Some of the time-kill analyses against P. aeruginosa, B. cepacia and ESBL-producing K. pneumoniae were in accordance with chequerboard results. Time-kill analyses against S. maltophilia did not confirm the synergy seen in chequerboard testing.
Observations on Screening-Based Research and Some Concerning Trends in the Literature (2010)

Academic drug discovery is being accompanied by a plethora of publications that report screening hits as good starting points for drug discovery or as useful tool compounds, whereas in many cases this is not so. These compounds may be protein-reactive but can also interfere in bioassays via a number of other means, and it can be very hard to prove early on that they represent false starts. This, for instance, makes it difficult for journals in their assessment of manuscripts submitted for publication. Wider awareness and recognition of these problematic compounds will help the academic drug-discovery community focus on and publish genuinely optimizable screening hits. This will be of general benefit.
Electron beam dynamics in combined guide and pump magnetic fields for free electron laser applications (1980)

The propagation of a cold relativistic electron beam in a free electron laser with an axial guide magnetic field is considered. The possibility of several steady-state helical trajectories for the electrons is shown, and the stability against perturbations and accessibility of such steady states is considered. Necessary and sufficient conditions for the stability are derived and indicate the importance of the transition region at the entrance of the laser. Possible modes of operation of the laser in different steady-state regimes are suggested and illustrated by numerical examples.
Advanced Combustion Diagnostics and Control for Furnaces, Fired Heaters and Boilers (2010)

The objective of this project was to develop and apply enabling tools and methods towards advanced combustion diagnostics and control of fired-equipment in large-scale petrochemical manufacturing. There are a number of technology gaps and opportunities for combustion optimization, including technologies involving advanced in-situ measurements, modeling, and thermal imaging. These technologies intersect most of manufacturing and energy systems within the chemical industry. This project leveraged the success of a previous DOE funded project led by Dow, where we co-developed an in-situ tunable diode laser (TDL) analyzer platform (with Analytical Specialties Inc, now owned by Yokogawa Electric Corp.). The TDL platform has been tested and proven in a number of combustion processes within Dow and outside of Dow. The primary focus of this project was on combustion diagnostics and control applied towards furnaces, fired heaters and boilers. Special emphasis was placed on the development and application of in-situ measurements for O2, CO and methane since these combustion gases are key variables in optimizing and controlling combustion processes safely. Current best practice in the industry relies on measurements that suffer from serious performance gaps such as limited sampling volume (point measurements), poor precision and accuracy, and poor reliability. Phase I of the project addressed these gaps by adding improved measurement capabilities such as CO and methane (ppm analysis at combustion zone temperatures) as well as improved optics to maintain alignment over path lengths up to 30 meters. Proof-of-concept was demonstrated on a modern olefins furnace located at Dow Chemical's facility in Freeport TX where the improved measurements were compared side-by-side to accepted best practice techniques (zirconium oxide and catalytic bead or thick film sensors). After developing and installing the improved combustion measurements (O2, CO, and methane), we also demonstrated the ability to improve control of an olefins furnace (via CO-trim) that resulted in significant energy savings and lower emissions such as NOx and other greenhouse gases. The cost to retrofit measurements on an existing olefins furnace was found to be very attractive, with an estimated payback achieved in 4 months or less.
Health monitoring of reinforced concrete shear walls using smart aggregates (2009)

In this paper, a smart aggregate-based approach is proposed for the structural health monitoring of a concrete shear wall structure. The piezoceramic-based smart aggregates were distributed in predetermined locations prior to the casting of the concrete structure to form an active-sensing system for the health monitoring purpose. To evaluate the damage in different areas, the concrete shear wall was sectioned into sub-domains and a wavelet-packet-based damage index matrix is proposed to evaluate the health status in these sections. A cyclic loading procedure was applied to gradually fail the concrete shear wall and the proposed structural health monitoring approach was used to perform structural health monitoring during this loading procedure. The experimental results have shown that the proposed smart aggregate-based approach effectively evaluated the damage status in different areas and detected the precautionary point to predict the structural failure. The proposed approach has the potential to be applied to the structural health monitoring of large-scale concrete shear wall structures.
A Generalised Solution to the Out-of-Sample Extension Problem in Manifold Learning (2011)

Manifold learning is a powerful tool for reducing the dimensionality of a dataset by finding a low-dimensional embedding that retains important geometric and topological features. In many applications it is desirable to add new samples to a previously learnt embedding, this process of adding new samples is known as the out-of-sample extension problem. Since many manifold learning algorithms do not naturally allow for new samples to be added we present an easy to implement generalized solution to the problem that can be used with any existing manifold learning algorithm. Our algorithm is based on simple geometric intuition about the local structure of a manifold and our results show that it can be effectively used to add new samples to a previously learnt embedding. We test our algorithm on both artificial and real world image data and show that our method significantly out performs existing out-of-sample extension strategies.
Purification, Characterization, and Gene Sequence of Michiganin A, an Actagardine-Like Lantibiotic Produced by the Tomato Pathogen<i>Clavibacter michiganensis</i>subsp.<i>michiganensis</i> (2006)

Members of the actinomycete genus Clavibacter are known to produce antimicrobial compounds, but so far none of these compounds has been purified and characterized. We have isolated an antimicrobial peptide, michiganin A, from the tomato pathogen Clavibacter michiganensis subsp. michiganensis, using ammonium sulfate precipitation followed by cation-exchange and reversed-phase chromatography steps. Upon chemical derivatization of putative dehydrated amino acids and lanthionine bridges by alkaline ethanethiol, Edman degradation yielded sequence information that proved to be sufficient for cloning of the gene by a genome-walking strategy. The mature unmodified peptide consists of 21 amino acids, SSSGWLCTLTIECGTIICACR. All of the threonine residues undergo dehydration, and three of them interact with cysteines via thioether bonds to form methyllanthionine bridges. Michiganin A resembles actagardine, a type B lantibiotic with a known three-dimensional structure, produced by Actinoplanes liguriae, which is a filamentous actinomycete. The DNA sequence of the gene showed that the michiganin A precursor contains an unusual putative signal peptide with no similarity to well-known secretion signals and only very limited similarity to the (only two) available leader peptides of other type B lantibiotics. Michiganin A inhibits the growth of Clavibacter michiganensis subsp. sepedonicus, the causal agent of ring rot of potatoes, with MICs in the low nanomolar range. Thus, michiganin A may have some potential in biological control of potato ring rot.
Intramolecular hydrogen bonds in aromatic sulphoxides: 1H nuclear magnetic resonance and acidity constant measurements (1973)

Comparative examination of the 1H n.m.r. chemical shifts and acidity constants of o-methylsulphinylphenol and o-hydroxyacetophenone shows that intramolecular hydrogen bonding is stronger for the carbonyl compound. The effect of bulky groups ortho to the SOCH3 and COCH3 groups indicates that these have different intramolecular hydrogen bonding patterns and different stereochemical requirements for molecular stabilization, when attached to an unsaturated system. Parallel behaviour is also found for the corresponding amino-derivatives. Possible electronic interactions between the sulphinyl group and the unsaturated ring in aromatic sulphoxides are discussed.
Performance analysis of file replication schemes in distributed systems (1987)

In distributed systems the efficiency of the network file system is a key performance issue. Replication of files and directories can enhance file system efficiency, but the choice of replication techniques is crucial. This paper studies a number of replication techniques, including remote access, prereplication, weighted voting, and two demand replication schemes: polling and staling. It develops a Markov chain model, which is capable of characterizing properties of file access sequences, including access locality and access bias. The paper compares the replication techniques under three different network file system architectures. The results show that, under reasonable assumptions, demand replication requires fewer file transfers than remote access, especially for files that have a high degree of access locality. Among the demand replication schemes, staling requires fewer auxiliary messages than polling.
Some Radical Exchange Reactions during Nitrite Ester Photolysis<sup>1</sup> (1965)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSome Radical Exchange Reactions during Nitrite Ester Photolysis1M. Akhtar, D. H. R. Barton, and P. G. SammesCite this: J. Am. Chem. Soc. 1965, 87, 20, 4601–4607Publication Date (Print):October 1, 1965Publication History Published online1 May 2002Published inissue 1 October 1965https://pubs.acs.org/doi/10.1021/ja00948a036https://doi.org/10.1021/ja00948a036research-articleACS PublicationsRequest reuse permissionsArticle Views327Altmetric-Citations41LEARN 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