gebhart/patrepeval huggingface dataset:
Remineralization of the tooth structure - The future of dentistry (2014)

Tooth structure undergoes continuous remineralization and demineralization in the oral environment. When this balance is changed, demineralization will progress leading to a degradation of the tooth structure. Minimal intervention is the key phrase in today's dental practice. Minimal intervention dentistry focuses on the least invasive treatment options possible in order to minimize tissue loss and patient discomfort. In the last decade there has been a veritable explosion of interest in technologies which may have value for remineralization of enamel and dentine or desensitization of exposed dentine affected by dental erosion. The key element is the usage and application of remineralizing agents to tooth structure to control the demineralization/ remineralization activity. This article looks at the process of remineralization and the various agents that enhance and /or promote remineralization and discusses their clinical implications.
Antimicrobial action of the leaf extract of moringa oleifera lam. (1995)

The ethnolic extract of the leaves of Moringa oleifera Lam. (Fam. Moringaceae) was tested for antimicrobial activities against Gram Positive - Bacillus cereus, Bacillus subtilis Staphylococcus aureus, Sarcina lutea: Gram negative - Escherichia coli and Acid fast Mycobacterium phlei. Significant antimicrobial activity of the extract was found in this study.
Ozone-UV irradiation effects on Ba2YCu3O7−<i>x</i> thin films (1988)

We studied the effects of ultraviolet (UV) irradiation in an ozone atmosphere on the electrical properties of Ba2 YCu3 O7−x thin films. The ozone-UV treatment had effects similar to plasma oxidation; it decreased the room-temperature resistivity and increased the zero resistance temperature of 460 nm Ba-Y-Cu-O thin films. Film resistivity decreased by about 25% in 100 min during ozone-UV treatment. This decreasing rate is one order of magnitude lower than plasma treatment. The ozone-UV treatment, however, resulted in a more stable film than the plasma treatment. The rate at which the room-temperature resistivity increased, measured 35 days after the ozone-UV treatment, was 0.06%/day, or about 1/6 that of the plasma treatment.
S/N and Error Rate Performance in AlGaAs Semiconductor Laser Preamplifier and Linear Repeater Systems (1982)

The applications of AlGaAs semiconductor laser preamplifier and linear repeaters in single mode optical fiber transmission systems were studied through the baseband signal-to-noise ratio and bit error rate performance measurement. Experiments were carried out with the Fabry-Perot cavity laser amplifiers whose characteristics are improved by reducing the input mirror reflectivity to 6 percent. The use of a preamplifier improves the minimum detectable power by 7.4 dB over the Si-APD direct detection level when the received signal is amplified by 30 dB before photodetection. The use of two linear repeaters increases the regenerative repeater gain by 37 dB. These experimental results are in good agreement with theoretical predictions based on the photon statistic master equation analysis.
Continuous preparation of functionalised calcium phosphate nanoparticles with adjustable crystallinity (2004)

Calcium phosphate nanoparticles can be prepared in almost uniform size and shape by a continuous precipitation process that also allows their functionalisation by organic molecules (DNA, surfactants).
Three‐Dimensional Heterocycles by Iron‐Catalyzed Ring‐Closing Sulfoxide Imidation (2018)

A general and atom-economical method for the synthesis of cyclic sulfoximines by intramolecular imidations of azido-containing sulfoxides using a commercially available Fe<sup>II</sup> phthalocyanine (Fe<sup>II</sup> Pc) as catalyst has been developed. The method conveys a broad functional group tolerance and the resulting three-dimensional heterocycles can be modified by cross-coupling reactions.
The use of cell division cycle mutants to investigate the control of microtubule distribution in the fission yeast <i>Schizosaccharomyces pombe</i> (1988)

We have characterized the changes in microtubule organization that occur through the cell division cycle of the fission yeast Schizosaccharomyces pombe by indirect immunofluorescence microscopy. During interphase, groups of cytoplasmic microtubules, independent of the spindle pole body (SPB), form an array extending between the cell tips. These microtubules are involved in positioning the nucleus at the cell equator and in the establishment of cell polarity. At mitosis, the interphase array disappears and is replaced by an intranuclear spindle extending between the now duplicated SPBs. Elongation of the spindle sees the appearance of astral microtubules emanating from the cytoplasmic face of the SPBs. These persist until the end of anaphase whereupon the spindle microtubules depolymerize and two microtubule organizing centres (MTOCs) at the cell equator re-establish the interphase array. We have used the unique properties of various cell division cycle mutants to investigate further the function of these different microtubule arrays and their temporal and positional control.
Bromelain Production: Current Trends and Perspective (2012)

Bromelain is a mixture of proteolytic enzymes derived from the stems and juice of pineapples. It has been extensively used in food industry; for meat tenderization, baking processes, and in prevention of browning of apple juice. Stem bromelain is a highly accepted phytotherapeutic agent. It has anti-tumor and antiinflammatory effects, use in wound healing, as digestive aids, etc. This review aims at presenting a detailed account on the level of achievement on bromelain production from the conventional methods. Specifically, the isolation, purification and the biochemical properties of bromelain are discussed. The study also focused on the current trends and the progress made in the production of recombinant stem bromelain in Escherichia coli. This involved cloning of stem bromelain gene and its expression, optimization of labscale fermentation conditions for E. coli harboring recombinant bromelain as well as the enzyme thermal and storage stability measured using differential scanning calorimetry. It is hoped that this review would provide relevant information to contemporary researchers who are active in the field of bromelain and other related proteases.
Gastric emptying in diabetes: an overview. (1996)

Gastric emptying is delayed in 30%-50% of patients with longstanding diabetes mellitus. The prevalence of disordered gastric emptying in patients with "early" Type 2 diabetes is controversial, but it has been suggested that gastric emptying is often accelerated. The pathogenesis of delayed gastric emptying in diabetes is poorly understood. It is, however, clear that acute changes in the blood glucose concentration have a major effect on gastric motor function and gastric emptying. There is an inverse relationship between the rate of gastric emptying and the blood glucose concentration, so that emptying is slower during hyperglycaemia and faster during hypoglycaemia. The motor dysfunctions responsible for delayed gastric emptying in patients with diabetes are heterogeneous. There is a high prevalence of upper gastrointestinal symptoms in diabetes. However, the correlation between symptoms and delay in gastric emptying is poor. Recent studies indicate that the blood glucose concentration modulates the perception of some sensations arising from the gastrointestinal tract. In both normal subjects and patients with diabetes the blood glucose response to oral carbohydrate and gastric emptying are related and there is evidence that modulation of the rate of gastric emptying, by dietary or pharmacological means, could be used to optimise glycaemic control. The use of prokinetic drugs, particularly cisapride, is currently the most effective approach to the treatment of symptomatic patients with gastroparesis. An improved understanding of the pathophysiology of both symptoms and delayed gastric emptying is fundamental to the development of more effective treatments.
Hepatitis C Virus Infection among Drug Users (2007)

[Objective] To learn the hepatitis C virus infection among drug users and its influential factors and provide scientific basis for HCV infection prevention.[Methods] Questionnaires were used to collect the data of drug users in Changsha and Zhuzhou;772 blood samples were collected;ELISA was applied to detect serum anti-HCV;SPSS 13.0 software was used to make statistical analysis.[Results]662 out of 772 drug users were detected positive with a total infection rate of 85.75%;simple element analysis showed that the difference was significant in the HCV infection rate between different sexes(P0.01),different ages(P0.05),different drug taking styles(P0.01),different vein transfusion times(P0.01) and whether sharing pinheads(P0.01).Multiple elements analysis showed that HCV infection among drug users has close relationship with sex,drug taking style,injection pinhead cleansing water and vein transfusion time.[Conclusion] Drug users are high-risk population of HCV infection;the influential factors of HCV infection are sex,drug taking style,injection pinhead cleansing water and vein transfusion time.
Cyclopropanation of unsaturated fatty acid methyl esters using diazomethane and palladium (II) acetate (1988)

Abstract Cyclopropanation of methyl esters of 10‐undecenoic, oleic, elaidic, erucic, trans ‐2‐docosenoic and a mixture of hydnocarpic and chaulmoogric acids was effected using diazomethane in the presence of palladium (II) acetate as catalyst. The products were isolated by silver ion thin‐layer chromatography and characterized by infrared, proton nuclear magnetic resonance and mass spectrometric techniques. Terminally unsaturated, α, β‐unsaturated and cyclopentene fatty acid esters were found to be more reactive than elaidate which in turn was more reactive than oleate. The reaction proceeds stereospecifically under milder conditions in a shorter time than with diiodomethane and zinc‐copper couple.
Gas Pressure Sintering of Composite of Si<sub>3</sub>N<sub>4</sub>-SiC System (1987)

The gas pressure sintering of silicon nitride with SiC containing Al2O3 and CeO2 as densification aid was investigated from 1800°C and 2MPa to 2050°C and 6MPa of nitrogen. The Si3N4-20wt% SiC-5wt% Al2O3-5wt% CeO2 composition sintered at 2050°C by two-step method had a density of 3.24g/cm3, flexural strength of about 780MPa, fracture toughness of about 4.9MN·m-3/2 and Vickers hardness of about 1700kg/mm2. It was found that addition of SiC to Si3N4 suppressed the growth of Si3N4 grains effectively.
Characterization of catecholamine‐mediated relaxations in rat isolated gastric fundus: evidence for an atypical β‐adrenoceptor (1991)

1. Experiments were carried out in order to characterize the receptors mediating relaxant responses to catecholamines in the rat gastric fundus. The effects of noradrenaline, isoprenaline and the 'atypical' or beta 3-adrenoceptor agonist, BRL 37344, on methacholine-induced tone were measured. Prazosin, propranolol and cyanopindolol were used as antagonists. 2. Relaxant responses to noradrenaline, in the presence of propranolol (1 microM) were antagonized in a concentration-dependent manner by prazosin (0.01 to 1 microM), although this antagonism was weak and non-competitive in nature. Relaxant responses to isoprenaline, in the presence of prazosin (0.1 microM), were antagonized only by the highest concentration of propranolol (1 microM) giving a pKB of 6.3 BRL 37344 also relaxed the rat gastric fundus in the presence of prazosin (0.1 microM), and the responses to BRL 37344 were unaffected by propranolol (1 microM). 3. Tachyphylaxis to BRL 37344 was observed, a second concentration-response curve being significantly shifted to the right. Exposure of tissues to BRL 37344 (1 microM) between concentration-response curves also caused an 11 fold rightward shift in the response to isoprenaline. 4. In the presence of prazosin (0.1 microM) and propranolol (1 microM), the rank order of potency of the agonists was: (-)-isoprenaline (1.0) greater than (-)-noradrenaline (0.39) greater than BRL 37344 (0.10). 5. Responses to BRL 37344 in the presence of prazosin (0.1 microM) and propranolol (1 microM) were antagonized by (+/-)-cyanopindolol (1 microM), with a pKB of 6.56. Responses to isoprenaline, under the same conditions, were antagonized in a competitive manner by (+/-)-cyanopindolol (0.1-1 microM), with the slope of a Schild plot close to unity and a pA2 value of 7.44. 6. The resistance to blockade by prazosin and propranolol and the antagonism by cyanopindolol of the responses mediated by isoprenaline and BRL 37344 suggest that atypical beta-adrenoceptors similar to 'atypical',beta-adrenoceptors in rat adipocytes and other tissues are present in the rat gastric fundus.
Natural Product Inspired Design of Enediyne Prodrugs via Rearrangement of an Allylic Double Bond (2003)

Cyclodeca-1,5-diyn-3-ene, the parent core of naturally occurring 10-membered ring enediyne antitumor antibiotics, decomposes at 37 degrees C with a t(1/2) value of 18 h. A prodrug approach was envisaged by in situ formation of the core structure via rearrangement of an allylic double bond. Three synthetic methods including intramolecular lithium acetylide addition to aldehyde, intramolecular Nozaki-Hiyama-Kishi reaction, and intramolecular Sonogashira cross-coupling have been established for synthesis of the enediyne precursors, (E)-3-acyloxy-4-(arylmethylidene)cyclodeca-1,5-diynes. The latter are transformed into 10-membered ring enediynes in the presence of a catalytic amount of Ln(fod)(3) under mild reaction conditions. Alternatively, the enediyne precursor dissociates in buffer solution into an allylic cation or a quinone methide intermediate, which reacts with a nucleophile (such as H(2)O) to form the bioactive enediyne. LC-MS data confirmed formation of the 10-membered ring enediyne from the precursor, which exhibits DNA cleavage activity and cytotoxicity against P388 cancer cell line.
Minimizing cost of HID lamp electronic ballast (2003)

An electronic ballast is one of the most cost sensitive products of power electronics. The high cost of available high intensity discharge (HID) lamp electronic ballasts is constraining their wide usage. A possible way to minimize the cost of an HID lamp ballast is to chose an optimal ballast operating frequency at which the required amount of components and their cost are minimal. As shown in this paper the minimal cost achieved at a selected operating frequency is in the 300 kHz region. Because of acoustic resonance problem in the HID lamp operating at high frequency, special attention was devoted to solution of this problem. The following items were used for cost minimization: a modern controller chip with integrated low and high side FET drivers; control, start up, and fault protection logic; an integrated magnetic-transformer-inductor; the simplest lamp power control circuit; bus voltage ripple for frequency modulation of lamp current to suppress acoustic resonance.
Height prediction from ulna length (2004)

Height is fundamental to assessing growth and nutrition, calculating body surface area, and predicting pulmonary function in childhood. Its measurement is hindered by muscle weakness, joint, or spinal deformity. Arm span has been used as a substitute, but is inaccurate. The objective of the study was to identify a limb measurement that precisely and reproducibly predicts height in childhood. Males (n=1144) and females (n=1199), aged 5 years 4 months to 19 years 7 months, without disability were recruited from Melbourne schools. Height, arm span, ulna, forearm, tibia, and lower leg lengths were measured with a Harpenden stadiometer and anthropometer. Prediction equations for height based on ulna length (U) and age in years (A) were developed using linear regression. Ulna centile charts were developed by the LMS method. For males, height (cm)=4.605U+1.308A+28.003 (R2=0.96); for females, height (cm)=4.459U+1.315A+31.485 (R2=0.94). Intra- and inter-observer variability was 0.41% and 0.61% relative to the mean, respectively. Height prediction equations from tibia, forearm, and lower leg length were calculated. We show that ulna measurement is reproducible and precisely predicts height in school-age children. It appears to be superior to arm span measurement when neuromuscular weakness, joint, or spinal deformity exists. Ulna growth charts should facilitate growth assessment.
Ciprofloxacin administration decreases enhanced ethanol elimination in ethanol-fed rats (1999)

Many colonic aerobic bacteria possess alcohol dehydrogenase (ADH) activity and are capable of oxidizing ethanol to acetaldehyde. Accordingly, some ingested ethanol can be metabolized in the colon in vivo via the bacteriocolonic pathway for ethanol oxidation. By diminishing the amount of aerobic colonic bacteria with ciprofloxacin treatment, we recently showed that the bacteriocolonic pathway may contribute up to 9% of total ethanol elimination in naive rats. In the current study we evaluated the role of the bacteriocolonic pathway in enhanced ethanol metabolism following chronic alcohol administration by diminishing the amount of gut aerobic flora by ciprofloxacin treatment. We found that ciprofloxacin treatment totally abolished the enhancement in ethanol elimination rate (EER) caused by chronic alcohol administration and significantly diminished the amount of colonic aerobic bacteria and faecal ADH activity. However, ciprofloxacin treatment had no significant effects on the hepatic microsomal ethanol-oxidizing system, hepatic ADH activity or plasma endotoxin level. Our data suggest that the decrease in the amount of the aerobic colonic bacteria and in faecal ADH activity by ciprofloxacin is primarily responsible for the decrease in the enhanced EER in rats fed alcohol chronically. Extrahepatic ethanol metabolism by gastrointestinal bacteria may therefore contribute significantly to enhanced EER.
Asymmetric distribution of the <i>Listeria monocytogenes</i> ActA protein is required and sufficient to direct actin‐based motility (1995)

Listeria monocytogenes is a Gram-positive facultative intracytoplasmic bacterial pathogen that exhibits rapid actin-based motility in eukaryotic cells and in cell-free cytoplasmic extracts. The protein product of the actA gene is required for bacterial movement and is normally expressed in a polarized fashion on the bacterial surface. Here we demonstrate that the ActA protein is sufficient to direct motility in the absence of other L. monocytogenes gene products, and that polarized localization of the protein is required for efficient unidirectional movement. We have engineered a fusion protein combining ActA with the C-terminal domain of the LytA protein of Streptococcus pneumoniae, which mediates high-affinity binding to DEAE-cellulose and to choline moieties present in the S. pneumoniae cell wall. DEAE-cellulose fragments or S. pneumoniae coated uniformly with the ActA/LytA fusion protein nucleate actin filament growth in cytoplasmic extracts, but do not move efficiently. However, when ActA/LytA-coated S. pneumoniae is grown to polarize the distribution of the fusion protein, the bacteria exhibit unidirectional actin-based movement similar to the normal movement of L. monocytogenes.
<scp>mTOR</scp>, metabolism, and the regulation of T‐cell differentiation and function (2012)

Upon antigen recognition, naive T cells undergo rapid expansion and activation. The energy requirements for this expansion are formidable, and T-cell activation is accompanied by dramatic changes in cellular metabolism. Furthermore, the outcome of antigen engagement is guided by multiple cues derived from the immune microenvironment. Mammalian target of rapamycin (mTOR) is emerging as a central integrator of these signals playing a critical role in driving T-cell differentiation and function. Indeed, multiple metabolic programs are controlled by mTOR signaling. In this review, we discuss the role of mTOR in regulating metabolism and how these pathways intersect with the ability of mTOR to integrate cues that guide the outcome of T-cell receptor engagement.
Ferroelectrics for silicon VLSI (1992)

The application of ferroelectrics to EEPROM, nonvolatile SRAMs, and sub-0.5 micron channel length MOS field effect transistors for silicon VLSI can significantly simplify device fabrication process, increase circuit density, and enhance device performance.
Branching MERA codes: A natural extension of classical and quantum polar codes (2014)

We introduce a new class of circuits for constructing efficiently decodable quantum and classical error-correction codes, based on a recently discovered contractible tensor network known as branching multi-scale entanglement renormalization ansatz [1]. We perform an in-depth study of a particular example that can be thought of as an extension to Arikan's polar code [2]-[4]. Notably, our numerical simulation show that these codes polarize the logical channels more strongly while retaining the log-linear decoding complexity using the successive cancellation decoder. These codes also display improved error-correcting capability with only a minor impact on decoding complexity. Efficient decoding is realized using powerful graphical calculus tools developed in the field of quantum many-body physics.
Design and Implementation of PDCP Protocol in LTE-A Air Interface Monitoring Instrumentation (2015)

Based on LTE-A air interface protocol stack,a new LTE-A air interface monitoring instrumentation is designed,the design of hardware and logical architecture in LTE-A air interface monitoring instrumentation is mainly analyzed,and the design idea of PDCP protocol data structure,data processing flow of PDCP transmitting entity,data processing flow of PDCP receiving entity are clarified. After the verification of actual development,the instrumentation achieves the desired functional requirements,and the design idea of PDCP protocol applies to the instrumentation successfully and proves the rationality of the data processing flow.
Structural basis of differential ligand recognition by two classes of bis-(3′-5′)-cyclic dimeric guanosine monophosphate-binding riboswitches (2011)

The bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) signaling pathway regulates biofilm formation, virulence, and other processes in many bacterial species and is critical for their survival. Two classes of c-di-GMP-binding riboswitches have been discovered that bind this second messenger with high affinity and regulate diverse downstream genes, underscoring the importance of RNA receptors in this pathway. We have solved the structure of a c-di-GMP-II riboswitch, which reveals that the ligand is bound as part of a triplex formed with a pseudoknot. The structure also shows that the guanine bases of c-di-GMP are recognized through noncanonical pairings and that the phosphodiester backbone is not contacted by the RNA. Recognition is quite different from that observed in the c-di-GMP-I riboswitch, demonstrating that at least two independent solutions for RNA second messenger binding have evolved. We exploited these differences to design a c-di-GMP analog that selectively binds the c-di-GMP-II aptamer over the c-di-GMP-I RNA. There are several bacterial species that contain both types of riboswitches, and this approach holds promise as an important tool for targeting one riboswitch, and thus one gene, over another in a selective fashion.