Journal articles: 'Base pair lifetime'

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Ferris, Zachary E., Qiushi Li, and Markus W. Germann. "Substituting Inosine for Guanosine in DNA: Structural and Dynamic Consequences." Natural Product Communications 14, no. 5 (May 1, 2019): 1934578X1985003. http://dx.doi.org/10.1177/1934578x19850032.

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Inosine differs from the guanosine nucleoside only by the absence of the N2 amino group. Both nucleosides also have similar electrostatic potentials. Therefore, substituting I for G has been used to probe various properties of nucleic acids and to facilitate the interpretation of binding studies. In particular, the absence of the amino group permits the assessment of its importance in the binding of ligands to the minor groove of duplex DNA. It has been known for some time that an I-C base pair is of lower stability than a regular G-C base pair, which needs to be considered when making DNA constructs containing inosine. However, it is generally assumed that both base pairs are structurally highly similar. To test this assumption in an identical sequence environment, we have determined the fine structure of two hairpin DNA substrates that differ only in the substitution of an I-C base pair for a G-C base pair. The structures have been solved using nuclear magnetic resonance (NMR) restraints in conjunction with Mardigras and molecular dynamics. The structural data are complemented with thermodynamic and dynamic data to get a comprehensive evaluation of the consequences of G-C vs I-C base pair substitutions. Our data show a strong similarity in the structures of the hairpins, but a significant difference in the melting temperatures, T m. This difference is also reflected in the drastically decreased base pair lifetime of 7.4 milliseconds compared to the G-C base pair lifetime of 155 milliseconds. The substitution of I-C for G-C is to probe for specific effect due to the amino group is satisfactory, as long as the lowered thermal stability and the drastically increased local dynamics are considered.

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McGuinness, Colin D., David Keszenman-Pereyra, Paul Dickinson, Colin J. Campbell, Beatrice A. Maltman, Till T. Bachmann, Peter Ghazal, and Jason Crain. "Base pair mismatch identification with DNA nanoswitch and long lifetime acridine fluorophore." Sensors and Actuators B: Chemical 148, no. 1 (June 2010): 342–46. http://dx.doi.org/10.1016/j.snb.2010.04.047.

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Berkoff, Bruce, Mike Hogan, Jane Legrange, and Robert Austin. "Dependence of oxygen quenching of intercalated methylene blue triplet lifetime on DNA base-pair composition." Biopolymers 25, no. 2 (February 1986): 307–16. http://dx.doi.org/10.1002/bip.360250211.

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Friederich, F., T. von Clarmann, B. Funke, H. Nieder, J. Orphal, M. Sinnhuber, G. P. Stiller, and J. M. Wissing. "Lifetime and production rate of NOx in the upper stratosphere and lower mesosphere in the polar spring/summer after the solar proton event in October–November 2003." Atmospheric Chemistry and Physics Discussions 12, no. 7 (July 18, 2012): 17703–21. http://dx.doi.org/10.5194/acpd-12-17703-2012.

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Abstract. We present altitude dependent lifetimes of NOx, determined with MIPAS/ENVISAT, for the southern polar region after the solar proton event in October–November 2003. Varying in latitude and decreasing in altitude they range from about two days at 64 km to about 20 days at 44 km. The lifetimes are controlled by transport, mixing and photolysis. We infer dynamical lifetimes by comparison of the observed decay to photolytical lifetimes calculated with the SLIMCAT 3-D Model. Photochemical loss contributes to the observed NOx depletion by 10% at 44 km, increasing with altitude to 35% at 62 km at a latitude of –63° S. At higher latitudes, the contribution of photochemical loss can be even more important. In addition, we show the correlation of modeled ionization rates and observed NOx densities under consideration of the determined lifetimes of NOx, and calculate altitude dependent effective production rates of NOx due to ionization. For that we compare ionization rates of the AIMOS data base with the MIPAS measurements for the whole Austral polar summer 2003/04. We derive effective NOx-production rates to be applied to the AIMOS ionization rates which range from about 0.2 NOx-molecules per ion pair at 44 km to 0.9 NOx-molecules per ion pair at 54 km at a latitude of –63° S. At –73° S, the NOx-production rate ranges from about 0.2 NOx-molecules per ion pair at 44 km to 1.0 NOx-molecules per ion pair at 60 km. These effective production rates are considerably lower than predicted by box model simulations which could hint at an overestimation of the modeled ionization rates.

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Friederich, F., T. von Clarmann, B. Funke, H. Nieder, J. Orphal, M. Sinnhuber, G. P. Stiller, and J. M. Wissing. "Lifetime and production rate of NO<sub>x</sub> in the upper stratosphere and lower mesosphere in the polar spring/summer after the solar proton event in October–November 2003." Atmospheric Chemistry and Physics 13, no. 5 (March 5, 2013): 2531–39. http://dx.doi.org/10.5194/acp-13-2531-2013.

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Abstract. We present altitude-dependent lifetimes of NOx, determined with MIPAS/ENVISAT (the Michelson Interferometer for Passive Atmospheric Sounding/the European Environment Satellite), for the Southern polar region after the solar proton event in October–November 2003. Between 50° S and 90° S and decreasing in altitude they range from about two days at 64 km to about 20 days at 44 km. The lifetimes are controlled by transport, mixing and photochemistry. We infer estimates of dynamical lifetimes by comparison of the observed decay to photochemical lifetimes calculated with the SLIMCAT 3-D Model. Photochemical loss contributes to the observed NOx depletion by 0.1% at 44 km, increasing with altitude to 45% at 64 km. In addition, we show the correlation of modelled ionization rates and observed NOx densities under consideration of the determined lifetimes of NOx, and calculate altitude-dependent effective production rates of NOx due to ionization. For that we compare ionization rates of the AIMOS data base with the MIPAS measurements from 15 October–31 December 2003. We derive effective NOx-production rates to be applied to the AIMOS ionization rates which range from about 0.2 NOx-molecules per ion pair at 44 km to 0.7 NOx-molecules per ion pair at 62 km. These effective production rates are considerably lower than predicted by box model simulations which could hint at an overestimation of the modelled ionization rates.

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Brümmer, Burghard, Gerd Müller, and Gunnar Noer. "A Polar Low Pair over the Norwegian Sea." Monthly Weather Review 137, no. 8 (August 1, 2009): 2559–75. http://dx.doi.org/10.1175/2009mwr2864.1.

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Abstract During the Lofotes cyclone experiment (LOFZY 2005), two polar lows developed one behind the other inside a cold-air outbreak from the north in the lee of Spitsbergen on 7 March 2005. Buoys, ship, and aircraft measurements as well as satellite imagery are applied to analyze the polar low bulk properties, the horizontal and vertical structure, and the mass, moisture, and heat budget. The lifetime of the system until landfall at northern Norway was 12 h. The generation occurred under the left exit region of an upper-level jet with 70 m s−1. Both polar lows had a radius of 100–130 km and extended to a height of about 2.5 km. The propagation speeds were within 14–17 m s−1 and correspond to the vertically averaged wind velocity of the lowest 2.5 km. In the polar low centers the pressure was about 2–3 hPa lower and the air was 1–2 K warmer and drier than in the surroundings. Aircraft measurements in the second of the two polar lows show an embedded frontlike precipitation band north of the center. Here, the highest low-level winds with 25 m s−1 and the largest fluxes of sensible and latent heat with 290 and 520 W m−2, respectively, were measured (areal averages amounted to 115 and 190 W m−2). Aircraft data show mass convergence in the subcloud layer (0–900 m) and divergence in the cloud layer (900–2500 m). Moisture supply by evaporation from the sea surface was about twice as large as that by convergence in the subcloud layer. The condensation rate in the cloud layer nearly equaled the rate of evaporation at the sea surface. Almost all condensed cloud water was converted to precipitation water. Only half of the precipitation at the cloud base reached the sea surface.

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Sorel, Océane, and Benjamin G. Dewals. "MicroRNAs in large herpesvirus DNA genomes: recent advances." Biomolecular Concepts 7, no. 4 (August 1, 2016): 229–39. http://dx.doi.org/10.1515/bmc-2016-0017.

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AbstractMicroRNAs (miRNAs) are small non-coding RNAs (ncRNAs) that regulate gene expression. They alter mRNA translation through base-pair complementarity, leading to regulation of genes during both physiological and pathological processes. Viruses have evolved mechanisms to take advantage of the host cells to multiply and/or persist over the lifetime of the host. Herpesviridae are a large family of double-stranded DNA viruses that are associated with a number of important diseases, including lymphoproliferative diseases. Herpesviruses establish lifelong latent infections through modulation of the interface between the virus and its host. A number of reports have identified miRNAs in a very large number of human and animal herpesviruses suggesting that these short non-coding transcripts could play essential roles in herpesvirus biology. This review will specifically focus on the recent advances on the functions of herpesvirus miRNAs in infection and pathogenesis.

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McClelland, Robert A., V. M. Kanagasabapathy, and N. Mathivanan. "Kinetics of breakdown of aryl hemiacetals of α-bromoacetophenone. Effect of phenol leaving groups on the lifetimes of tetrahedral intermediates." Canadian Journal of Chemistry 69, no. 12 (December 1, 1991): 2084–93. http://dx.doi.org/10.1139/v91-301.

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The kinetics of breakdown of seven aryl hemiacetals of α-bromoacetophenone (TOH) have been examined, with aryl substituents 4-MeO, 4-Me, 3-Me, H, 3-MeO, 4-Cl, 3-Cl. The hemiacetals were generated as intermediates in the aqueous bromination of α-aryloxystyrenes, where the breakdown of the hemiacetal is the rate-limiting stage in the overall reaction. Base catalysis of the breakdown shows large Brønsted β values (0.8–1.0) and similarly large βlg values (−0.8 to −1.0). These are argued to arise because of a preassociation mechanism in which the hydrogen-bonded intermediate [Formula: see text] loses aryloxide faster than diffusional separation of the acid–base pair. This mechanism is enforced by lifetimes of the deprotonated hemiacetals TO− in the 1010–1012 s−1 range. Such lifetimes were estimated in two independent ways, by extrapolation of data previously obtained for alkyl hemiacetals of α-bromoacetophenone, and through a calculation based upon the experimental catalytic coefficients, and estimates of the acidity constants for TOH and the equilibrium constants for formation of hydrogen-bonded complexes. The pH-independent breakdown has βlg = −1.03, and the point lies near the Brønsted line for the carboxylate catalysts. This, therefore, also occurs by a preassociation mechanism with water as the catalyst forming the intermediate [Formula: see text], which loses aryloxide faster than diffusional separation. Catalysis by hydroxide ion occurs with rate constants of 8 × 109 M−1 s−1 independent of aryl substituent. This represents rate-limiting diffusional encounter of the hemiacetal and hydroxide ion, the hydrogen-bonded intermediate [Formula: see text] rapidly proceeding on to products. Acid catalysis of the hemiacetal breakdown occurs by a class "n" mechanism in which the acid assists departure of the substitued phenol. Alkyl hemiacetals of α-bromoacetophenone break down by a class "e" mechanism where the leaving group is fully protonated before bond cleavage. The class "e" mechanism can be excluded for the aryl derivatives, since rate constants much greater then diffusion are required to explain the observed catalytic coefficients. The different mechanism is followed in order to avoid the fully protonated hemiacetal, which, being of an O-protonated anisole structure, is of very high energy. Key words: hemiacetal kinetics, preassociation, intermediate lifetime.

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Nong, Wan Hua, Fei Gao, Rong Fu, and Xiao Ming Han. "Investigation of Friction Temperature in Railway Disc Brake." Advanced Materials Research 479-481 (February 2012): 202–6. http://dx.doi.org/10.4028/www.scientific.net/amr.479-481.202.

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The distribution of temperature on the rubbing surface is an important factor influencing the lifetime of a brake disc. With a copper-base sintered brake pad and a forge steel disc, up-to-brake experiments have been conducted on a full-scale test bench at a highest speed of 200 Km/h and a maximum braking force of 22.5 KN. The temperature distributions on brake disc surface have been acquired by an infrared thermal camera, and the contact pressure on the contact surface of the friction pair has been calculated by the finite element software ABAQUS. The results show that the area and thermal gradient of the hot bands increase with the increase of braking speed and braking force. The hot bands occur in priority at the radial location of r=200 mm and r=300 mm, and move radially in the braking process. The finite element modelling calculation indicates that the distribution of the contact pressure on the disc surface in radial direction is in a "U"-shape. The maximum contact pressure occur at the radial locations of r=200 mm and r=300 mm, and the minimum contact pressure occur in the vicinity of the mean radius of the disc. The conformity of contact pressure distributions with the practical temperature evolutions indicates that the non-uniform distribution of the contact pressure is the factor resulting in the appearance of hot bands on the disc surface.

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Dodson, Dillon S., and Jennifer D. Small Griswold. "Droplet inhomogeneity in shallow cumuli: the effects of in-cloud location and aerosol number concentration." Atmospheric Chemistry and Physics 19, no. 11 (June 4, 2019): 7297–317. http://dx.doi.org/10.5194/acp-19-7297-2019.

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Abstract. Aerosol–cloud interactions are complex, including albedo and lifetime effects that cause modifications to cloud characteristics. With most cloud–aerosol interactions focused on the previously stated phenomena, there have been no in situ studies that focus explicitly on how aerosols can affect large-scale (centimeters to tens of meters) droplet inhomogeneities within clouds. This research therefore aims to gain a better understanding of how droplet inhomogeneities within cumulus clouds can be influenced by in-cloud droplet location (cloud edge vs. center) and the surrounding environmental aerosol number concentration. The pair-correlation function (PCF) is used to identify the magnitude of droplet inhomogeneity from data collected on board the Center for Interdisciplinary Remotely Piloted Aircraft Studies (CIRPAS) Twin Otter aircraft, flown during the 2006 Gulf of Mexico Atmospheric Composition and Climate Study (GoMACCS). Time stamps (at 10−4 m spatial resolution) of cloud droplet arrival times were measured by the Artium Flight phase-Doppler interferometer (PDI). Using four complete days of data with 81 non-precipitating cloud penetrations organized into two flights of low-pollution (L1, L2) and high-pollution (H1, H2) data shows enhanced inhomogeneities near cloud edge as compared to cloud center for all four cases. Low-pollution clouds are shown to have enhanced overall inhomogeneity, with flight L2 being solely responsible for this enhanced inhomogeneity. Analysis suggests cloud age plays a larger role in the amount of inhomogeneity experienced than the aerosol number concentration, with dissipating clouds showing increased inhomogeneities as compared to growing or mature clouds. Results using a single, vertically developed cumulus cloud demonstrate enhanced droplet inhomogeneity near cloud top as compared to cloud base.

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Ghaleb, Khaled Ismail, Magdy Mohamed Afifi, and Mohamed Mohamed El Gohary. "ASSESSMENT OF DIAGNOSTIC TECHNIQUES OF URINARY TUBERCULOSIS." Mediterranean Journal of Hematology and Infectious Diseases 5, no. 1 (June 3, 2013): e2013034. http://dx.doi.org/10.4084/mjhid.2013.034.

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Khalid Ghaleb a,* , Magdy Afifib, Mohamad El-Gohary c aDepartment of Medical Laboratories, Faculty of Applied Medical Science, King Khalid University, Bisha 551, Saudia Arabia bDepartment of Botany and Microbiology, Faculty of Science, Al-Azhar University, Assuit 71524, Egypt cDepartment of Internal Medicine, Faculty of Medicine, Al-Azhar University, Assuit, Egypt The corresponding author e-mail: kh_ghaleb4@hotmail.com Current Tel: 00966595388496 Saudia, 00201119338055 Egypt The place of the study worked : Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, Assuit 71524, Egypt, e-mail: afifi_magdy@ymail.com Tel: 00201006554961 Abstract Early diagnosis of active tuberculosis remains an elusive challenge. In addition, one third of the world's population is latently infected with Mycobacterium tuberculosis (Mtb) and up to 10% of infected individuals develop tuberculosis (TB) in their lifetime. In this investigation, the incidence of urinary tuberculosis among renal patients was studied. Three hundreds urine samples were processed for detection of Mtb by Ziehl-Neelson (ZN) smear examination, Lowenstein Jensen (LJ) medium, radiometric BACTEC460 system as well as polymerase chain reaction (PCR) and DNA Enzyme Immunoassay (DEIA) test. Out of 300 urine samples, 2 were positive by both ZN smears and LJ medium with incidence rate of 0.66 %, 3 positive samples by BACTEC460 culture system with incidence of 1%. PCR assay gave more positive results than smear and culture examination (i.e. 8 positive samples with incidence rate of 2.6%). The specificities were 25% for both ZN smears and LJ medium, 37.5% for BACTEC460 culture system, and 100% for PCR test, while sensitivities of all assays were 100%. Thus PCR is a rapid and sensitive method for the early diagnosis of urinary tuberculosis. Keywords: List of abbreviations:Acid Fast Bacilli (AFB)-Base pair (bp)-DNA Enzyme Immunoassay (DEIA) -Extrapulmonary Tuberculosis (EPTB)-International Union Against Tuberculosis (IUAT)-Lowenstein Jensen (LJ)-Mycobacterium tuberculosis (Mtb) -Polymerase Chain Reaction (PCR)-Tuberculosis (TB)-Urinary Tuberculosis (UTB-Urogenital Tuberculosis (UGTB)-Ziehl-Neelson (ZN)

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Bhattacharya, Pratip K., Julie Cha, and Jacqueline K. Barton. "1H NMR determination of base‐pair lifetimes in oligonucleotides containing single base mismatches." Nucleic Acids Research 30, no. 21 (November 1, 2002): 4740–50. http://dx.doi.org/10.1093/nar/gkf601.

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Bachir, Bouamoud, Ouacha Ali, Habbani Ahmed, and Elkoutbi Mohamed. "Proactive Schema Based Link Lifetime Estimation and Connectivity Ratio." Scientific World Journal 2014 (2014): 1–6. http://dx.doi.org/10.1155/2014/172014.

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The radio link between a pair of wireless nodes is affected by a set of random factors such as transmission range, node mobility, and environment conditions. The properties of such radio links are continually experienced when nodes status balances between being reachable and being unreachable; thereby on completion of each experience the statistical distribution of link lifetime is updated. This aspect is emphasized in mobile ad hoc network especially when it is deployed in some fields that require intelligent processing of data information such as aerospace domain.

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Shi, Pan, Yanan Zhang, Pei Lv, Wei Fang, Shenglong Ling, Xiaoqi Guo, Dong Li, et al. "A genetically encoded small-size fluorescent pair reveals allosteric conformational changes of G proteins upon its interaction with GPCRs by fluorescence lifetime based FRET." Chemical Communications 56, no. 51 (2020): 6941–44. http://dx.doi.org/10.1039/d0cc02691c.

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Bégué, D., E. Guille, S. Metz, M. A. Arnaud, H. Santos Silva, M. Seck, P. Fayon, C. Dagron-Lartigau, P. Iratcabal, and R. C. Hiorns. "Graphene-based acceptor molecules for organic photovoltaic cells: a predictive study identifying high modularity and morphological stability." RSC Advances 6, no. 17 (2016): 13653–56. http://dx.doi.org/10.1039/c5ra25531g.

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Clouatre, Maison, and Makhin Thitsa. "Data-driven Sliding Mode Control for Pulses of Fluorescence in STED Microscopy Based on Förster Resonance Energy Transfer Pairs." MRS Advances 5, no. 29-30 (2020): 1557–65. http://dx.doi.org/10.1557/adv.2020.11.

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ABSTRACTPairs of conjugate donor-acceptor fluorescent probes have proven themselves useful in stimulated emission depletion (STED) microscopy in recent years. For instance, it has been shown that the lifetime of said probes directly correlates to the resolution of the microscope. However, once the lifetimes of the probes have been optimized, it is desirable to control their fluorescence in order to improve the resolution further. Here, we propose combining model-free control with sliding mode control to track nanosecond pulses of red-shifted acceptor fluorescence in order to inhibit visible light emitted from the image plane, shrink the point spread function, and subsequently improve the resolution of the microscope. This is achieved by automatic adjustment of the STED laser beam pump power. This controller is numerically simulated against a generic model created from Förster resonance energy transfer (FRET) theory. However, since it is data-driven, it can be easily applied to various physical systems with drastically different dynamics. This work provides a reliable theoretic control solution to modern super resolution microscopy for biological imaging.

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Wessig, P., N. Behrends, M. U. Kumke, U. Eisold, T. Meiling, and C. Hille. "Two-photon FRET pairs based on coumarin and DBD dyes." RSC Advances 6, no. 40 (2016): 33510–13. http://dx.doi.org/10.1039/c6ra03983a.

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Leijon, M., and J. L. Leroy. "Internal motions of nucleic acid structures and the determination of base-pair lifetimes." Biochimie 79, no. 12 (December 1997): 775–79. http://dx.doi.org/10.1016/s0300-9084(97)86936-2.

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Loryuenyong, Vorrada, Khajornsak Intong, Vannapa Pongpraphan, Watcharothai Suksakkhee, and Achanai Buasri. "Photocatalytic Application of Graphene-Based TiO₂ Nanocomposite." Solid State Phenomena 266 (October 2017): 79–83. http://dx.doi.org/10.4028/www.scientific.net/ssp.266.79.

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Titanium dioxide (TiO2) is one of the most well known photocatalytic materials. However, TiO2 is only photoactive to ultraviolet (UV) light, and the lifetime of the electron-hole pair recombination is too short. In this work, TiO2 anatase nanotubes with an energy band gap of 3.01 eV and specific surface area of 112.46 m2/g were synthesized via hydrothermal method. The results showed that, by incorporating graphene oxide (XGO) and reduced graphene oxide (RGO), the photodegradation efficiency could be enhanced by increasing electron lifetime and charge carrier separation, as well as narrowing the energy band gap. The examination of photodegradation activity under UVC irradiation indicated that a maximum photodegradation efficiency was achieved with TiO2-XGO nanocomposite due to its high specific surface area and strong hydrophilic property.

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Bansal, Dipika. "Prevalence and Impact of Low Back Pain in a Community-Based Population in Northern India." Pain Physician 4;23, no. 7;4 (July 14, 2020): E389—E398. http://dx.doi.org/10.36076/ppj.2020/23/e389.

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Background: Low back pain (LBP) ranks first for disability and sixth for overall burden on world health, with an annual approximate cost of $135 billion. There are limited data on the prevalence and risk factors for LBP in developing countries, such as India. Objectives: To assess the prevalence, pain intensity, and quality of life (QOL) associated with LBP in northern India. Study Design: Cross-sectional study. Settings: Northern states of India. Methods: Adult population of different strata of the community were interviewed. Lifetime, point, 1-year, and age standardized lifetime prevalence with 95% confidence intervals (CI) and QOL, and pain intensity using the Numeric Rating Scale (NRS-11) were determined. Binary logistic regression test was conducted to determine the predictors of LBP prevalence; odds ratio (OR) with 95% CI are presented. Significance level was set at P ≤ 0.05. Results: A total of 1,531 patients were interviewed of whom 48% were men and mean (standard deviation [SD]) age was 32 (10) years. Lifetime, point, 1-year, and age standardized lifetime prevalence (95% CI) were 57% (54%–59%), 32% (30%–34%), 48% (46%–51%), and 59% (56%–62%), respectively. Average (SD) NRS-11 was 4.2 (2.6). Significant impact of LBP on sleep (24%), depression/psychological problems (24%), and social life (28%) were observed. Women (OR, 2.23; 95% CI, 1.80–2.77; P < 0.05), walking/lifting activity (OR, 1.362; 95% CI, 1.097– 1.692; P < 0.05), and increasing age (OR, 1.03; 95% CI, 1.02–1.04; P < 0.05) were most significant positive predictors of LBP. Limitations: The progression of LBP could not be assessed in the enrolled patients. Conclusions: LBP is highly prevalent in India, adversely affecting QOL in respondents. This calls for action by health officials to plan prevention, education, and management programs in the society. Key words: Low back pain, pain intensity, prevalence, incidence, quality of life

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Hanoch, Yaniv, Talya Miron-Shatz, and Mary Himmelstein. "Genetic testing and risk interpretation: How do women understand lifetime risk results?" Judgment and Decision Making 5, no. 2 (April 2010): 116–23. http://dx.doi.org/10.1017/s1930297500000978.

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AbstractGenetic screening for BRCA1 and BRCA2 gives women the opportunity for early detection, surveillance, and intervention. One key feature of genetic testing and counseling is the provision of personal lifetime risk. However, little attention has been paid to how women interpret lifetime risk information, despite the fact that they base screening, treatment and family planning decisions on such information. To study this vital issue, we set out to test the ability of women to choose the most appropriate interpretation of National Cancer Institute’s (NCI) message about lifetime risk of developing cancer for a woman with altered BRCA1 and BRCA2 genes. Participants included 277 women who had not undergone genetic testing or had cancer and 207 women who had undergone genetic testing or had cancer. Over 50% of the women who had not undergone genetic testing or had cancer and 40% of those who had undergone genetic testing or had cancer misunderstood NCI’s information. Furthermore, in line with a growing body of research, we found that high numeracy level (objective or subjective) is positively associated with a woman’s ability to correctly interpret NCI’s message.

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Mattsson, P., and L. Ekselius. "Migraine, Major Depression, Panic Disorder, and Personality Traits in Women Aged 40-74 Years: A Population-Based Study." Cephalalgia 22, no. 7 (September 2002): 543–51. http://dx.doi.org/10.1046/j.1468-2982.2002.00407.x.

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This study investigates the associations between migraine on the one hand and lifetime major depression, lifetime panic disorder, and neuroticism evaluated using the Swedish universities Scales of Personality on the other. A neurologist clinically assessed 728 women aged 40-74 years attending a population-based mammography screening programme. The associations between lifetime migraine and personality traits and psychiatric disorders were insignificant in multivariable analysis. However, in old women (60-74 years) the risk for active migraine was strongly associated with a history of major depression and high levels of stress susceptibility and somatic trait anxiety. Furthermore, in old women, high levels of stress susceptibility and somatic trait anxiety were associated with low ratings of migraine pain intensity and lower levels of these traits with high ratings after controlling for disability during migraines, whereas there were only small differences in middle-aged women. The results suggest that certain aspects of neuroticism are important mental correlates of the ability of old women to endure migraine pain.

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Li, De Sheng, Nian Yu Zou, Yun Cui Zhang, Xiao Yang He, and Yi Yang. "Study of High-Power White LED's Lifetime Based on Accelerated Life Test." Advanced Materials Research 800 (September 2013): 205–9. http://dx.doi.org/10.4028/www.scientific.net/amr.800.205.

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The study of LED reliability becomes more and more important with LED widely used in various areas, and accelerated life test (ALT) as an element of reliability test is widely used to predict the lifetime of LED. In this paper, ALTs have been carried out at various current levels and various temperature levels. In the current ALT experiment, three kinds of stressing currents were demonstrated for 1W white LEDs and lumen flux of the tested LEDs were studied, and based on Eyting model, lifetime of the tested LEDs is calculated about 6.86×105h. In the temperature ALT experiment, two kinds of stressing temperature were demonstrated for the same type of white LEDs and lumen flux were also studied, and based on Arrhenius model, lifetime of the tested LEDs is calculated about 7.41×105h. In addition, the color shifting velocity is faster than lumens depreciation velocity was observed in our experiment, which means the lifetime evaluating of white LED should be paid more attention.

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Altug, Ziya. "Lifestyle Medicine for Chronic Lower Back Pain: An Evidence-Based Approach." American Journal of Lifestyle Medicine 15, no. 4 (July 2021): 425–33. http://dx.doi.org/10.1177/1559827620971547.

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Lower back pain is a leading cause of work absence and activity limitations globally, with a 60% to 85% lifetime chance of occurrence. This article highlights the role that lifestyle medicine plays in managing lower back pain as a cost-effective intervention strategy. It is suggested that lifestyle medicine strategies, such as incorporating whole foods and a plant-based diet, sustainable physical activity and mind-body exercises, restorative sleep, stress resiliency, awareness and mitigation of substance abuse and addiction, and establishing meaningful social networks and self-care strategies, be a part of managing chronic lower back pain.

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Lee, Alpha A., Jason C. S. Lau, Hannah J. Hogben, Till Biskup, Daniel R. Kattnig, and P. J. Hore. "Alternative radical pairs for cryptochrome-based magnetoreception." Journal of The Royal Society Interface 11, no. 95 (June 6, 2014): 20131063. http://dx.doi.org/10.1098/rsif.2013.1063.

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There is growing evidence that the remarkable ability of animals, in particular birds, to sense the direction of the Earth's magnetic field relies on magnetically sensitive photochemical reactions of the protein cryptochrome. It is generally assumed that the magnetic field acts on the radical pair [FAD •− TrpH • + ] formed by the transfer of an electron from a group of three tryptophan residues to the photo-excited flavin adenine dinucleotide cofactor within the protein. Here, we examine the suitability of an [FAD •− Z • ] radical pair as a compass magnetoreceptor, where Z • is a radical in which the electron spin has no hyperfine interactions with magnetic nuclei, such as hydrogen and nitrogen. Quantum spin dynamics simulations of the reactivity of [FAD •− Z • ] show that it is two orders of magnitude more sensitive to the direction of the geomagnetic field than is [FAD •− TrpH • + ] under the same conditions (50 µT magnetic field, 1 µs radical lifetime). The favourable magnetic properties of [FAD •− Z • ] arise from the asymmetric distribution of hyperfine interactions among the two radicals and the near-optimal magnetic properties of the flavin radical. We close by discussing the identity of Z • and possible routes for its formation as part of a spin-correlated radical pair with an FAD radical in cryptochrome.

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George Abraham, Bobin, Karen S. Sarkisyan, Alexander S. Mishin, Ville Santala, Nikolai V. Tkachenko, and Matti Karp. "Fluorescent Protein Based FRET Pairs with Improved Dynamic Range for Fluorescence Lifetime Measurements." PLOS ONE 10, no. 8 (August 3, 2015): e0134436. http://dx.doi.org/10.1371/journal.pone.0134436.

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Sánchez, F. García, A. Navas Díaz, and C. Torijas. "Fluorescence lifetime determination of quinine and quinidine based on modulation measurements by ion-pair diastereomeric complexation." Biomedical Chromatography 13, no. 2 (April 1999): 179–80. http://dx.doi.org/10.1002/(sici)1099-0801(199904)13:2<179::aid-bmc873>3.0.co;2-l.

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Mueller, Daniel, Mark Obermann, Min-Suk Yoon, Franziska Poitz, Niels Hansen, Marc-Andre Slomke, Peter Dommes, Elke Gizewski, Hans-Christoph Diener, and Zaza Katsarava. "Prevalence of trigeminal neuralgia and persistent idiopathic facial pain: A population-based study." Cephalalgia 31, no. 15 (September 29, 2011): 1542–48. http://dx.doi.org/10.1177/0333102411424619.

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Objective: To estimate the lifetime prevalence of trigeminal neuralgia (TN) and persistent idiopathic facial pain (PIFP) in a population-based sample in Germany. Methods: A total of 3336 responders of 6000 contacted inhabitants of the city of Essen in Germany were screened using a self-assessment questionnaire. 327 individuals, who reported recurrent facial pain and randomly selected 150 (5% of 3009) screening negative subjects, received a phone interview by one of six neurologists and if necessary a face-to-face examination. Those with suspected TN or PIFP following the phone interview underwent neurological examination by two neurologists who were unaware of the presumed diagnosis. A random group of 25 (10% of 247) phone interview negative subjects was examined face-to-face. All suspected cases of PIFP received otorhinolaryngological examination and diagnostic cranial magnetic resonance imaging (MRI). In TN patients the number of vessel-nerve contacts was determined by thin-slice cranial MRI. Results: Lifetime prevalence of TN was estimated to be 0.3% [10 of 3336; 95% CI 0.1–0.5%], of PIFP 0.03% [1 of 3336; 95% CI < 0.08%]. Thin-slice cranial MRI detected five vessel-nerve contacts and no symptomatic lesions in the 10 TN patients. Conclusions: This large population-based study revealed that TN and PIFP are rare facial pain disorders.

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Lenik, Joanna, and Cecylia Wardak. "Properties of ibuprofen ion-selective electrodes based on the ion pair complex of tetraoctylammonium cation." Open Chemistry 8, no. 2 (April 1, 2010): 382–91. http://dx.doi.org/10.2478/s11532-010-0005-3.

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AbstractIbuprofen membrane electrodes based on different plasticizers: diisobutyl phthalate (DIBP), o-nitrophenyloctyl ether (o-NPOE), dioctyl sebacate (DOS) and tetraoctylammonium 2-(4-isobutylphenyl)propionate were prepared. All electrodes show: a near Nernstian slope of characteristic (58.3–60.9 mV decade−1) in the measurement range (10−4–10−1 mol L−1), limit of detection (5.0×10−5 mol L−1), really long lifetime (12 months), dependence of the electrode potential on pH (5.5–9.0), reproducibility of potential (0.6–1.2 mV) and selectivity coefficients in relation to some organic and inorganic anions. The electrodes were applied for the determination of ibuprofen in tablets by the calibration curve method and the standard addition method.

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Cancio, Roberto. "Pain and Masculinity: A Cohort Comparison between Mexican American Vietnam and Post–9/11 Combat Veterans." Men and Masculinities 23, no. 3-4 (March 14, 2018): 725–48. http://dx.doi.org/10.1177/1097184x18761779.

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Using twenty-six interviews with Mexican American veterans, this study analyzes cohort effects between Vietnam War veterans to Iraq and/or Afghanistan veterans on the meanings and experiences of pain from combat, masculinity, and how ethnicity affects expressions of pain. Although there were relative similarities between the cohorts, differences arose because of age. Vietnam veterans understood their pain to be long-lasting and have built coping mechanisms around a lifetime of pain, as opposed to younger veterans who have not yet solidified coping strategies. Machismo plays a dynamic part in the expression and daily experience with pain for young veterans, as opposed to older veterans who enjoy relaxed gendered obligations based on their age. Finally, older veterans used family as a base of social support, as opposed to younger veterans who found support from peer-mentor programs. In addition, respondents indicated that machismo acted more as guiding principle and offered them motivations to seek help, and not necessarily barriers to health. Overall, both cohorts are governed by strict gender standards and expressions influenced by their ethnic identity. Findings suggest that the study of race/ethnicity and age plays a fundamental framework from which to understand the experiences and behaviors of pain.

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Leijon, M., and A. Gräslund. "Effect of length and netropsin binding on base-pair lifetimes of oligonucleotides with the center core GCGAATTCGC." Nucleosides and Nucleotides 10, no. 1-3 (January 1991): 669–70. http://dx.doi.org/10.1080/07328319108046567.

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Schwalb, Nina K., Thomas Michalak, and Friedrich Temps. "Ultrashort Fluorescence Lifetimes of Hydrogen-Bonded Base Pairs of Guanosine and Cytidine in Solution." Journal of Physical Chemistry B 113, no. 51 (December 24, 2009): 16365–76. http://dx.doi.org/10.1021/jp904883n.

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Kim, JH, S. Kim, S.-I. Suh, S.-B. Koh, K.-W. Park, and K. Oh. "Interictal Metabolic Changes in Episodic Migraine: A Voxel-Based FDG-PET Study." Cephalalgia 30, no. 1 (July 1, 2009): 53–61. http://dx.doi.org/10.1111/j.1468-2982.2009.01890.x.

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Whereas there are many H215O-positron emission tomography (PET) studies demonstrating neuronal activation during acute migraine attacks, little information is available on the interictal (headache-free period) glucose metabolic changes in migraine. We therefore conducted voxel-based statistical parametric mapping analysis of 18F-fluorodeoxyglucose-PET to evaluate interictal metabolic differences between 20 episodic migraine patients (four with aura; three men; mean age 34.0 ± 6.4 years) and 20 control subjects. Separate correlation analyses were performed to delineate a possible relationship between regional glucose metabolism and disease duration or lifetime headache frequency in migraine patients. Group comparison showed that migraine patients had significant hypometabolism in several regions known to be involved in central pain processing, such as bilateral insula, bilateral anterior and posterior cingulate cortex, left premotor and prefrontal cortex, and left primary somatosensory cortex (uncorrected P < 0.001, corrected P < 0.05 with small volume corrections). Correlation analyses showed that regional metabolism of the insula and anterior cingulate cortex had significant negative correlations with disease duration and lifetime headache frequency (uncorrected P < 0.001, corrected P < 0.05 with small volume corrections). Our findings of progressive glucose hypometabolism in relation to increasing disease duration and increasing headache frequency suggest that repeated migraine attacks over time lead to metabolic abnormalities of selective brain regions belonging to the central pain matrix.

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Falohun, Tokunbo, and Michael J. McShane. "An Optical Urate Biosensor Based on Urate Oxidase and Long-Lifetime Metalloporphyrins." Sensors 20, no. 4 (February 11, 2020): 959. http://dx.doi.org/10.3390/s20040959.

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Gout is a condition that affects over 8 million Americans. This condition is characterized by severe pain, and in more advanced cases, bone erosion and joint destruction. This study explores the fabrication and characterization of an optical, enzymatic urate biosensor for gout management, and the optimization of the biosensor response through the tuning of hydrogel matrix properties. Sensors were fabricated through the co-immobilization of oxygen-quenched phosphorescent probes with an oxidoreductase within a biocompatible copolymer hydrogel matrix. Characterization of the spectral properties and hydrogel swelling was conducted, as well as evaluation of the response sensitivity and long-term stability of the urate biosensor. The findings indicate that increased acrylamide concentration improved the biosensor response by yielding an increased sensitivity and reduced lower limit of detection. However, the repeatability and stability tests highlighted some possible areas of improvement, with a consistent response drift observed during repeatability testing and a reduction in response seen after long-term storage tests. Overall, this study demonstrates the potential of an on-demand, patient-friendly gout management tool, while paving the way for a future multi-analyte biosensor based on this sensing platform.

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Kim, Hayeon, Malolan Sri Rajagopalan, Sushil Beriwal, and Kenneth Smith. "Cost-effectiveness analysis of single fraction of stereotactic body radiotherapy compared to single fraction of external beam radiotherapy for palliation of vertebral bone metastases." Journal of Clinical Oncology 32, no. 30_suppl (October 20, 2014): 26. http://dx.doi.org/10.1200/jco.2014.32.30_suppl.26.

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26 Background: Stereotactic body radiotherapy (SBRT) has been proposed for the palliation of painful vertebral bone metastases because higher radiation doses may confer better pain control. A Phase III clinical trial comparing SBRT with single fraction external beam radiotherapy (EBRT) is now ongoing. We performed a cost-effectiveness analysis to compare these strategies. Methods: A Markov model, using a 1-month cycle over a lifetime horizon, was developed to compare the cost effectiveness of SBRT (16 or 18 Gy in 1 fraction) to 8 Gy in 1 fraction of EBRT. Transition probabilities, quality of life utilities, and costs associated with SBRT and EBRT were captured in the model. Costs were based on Medicare reimbursement in 2014. Strategies were compared using the incremental cost effectiveness ratio (ICER), and effectiveness was measured in quality-adjusted life years (QALYs). To account for uncertainty, one-way and probabilistic sensitivity analyses were performed. Strategies were evaluated with a willingness-to-pay (WTP) threshold of $100,000/QALY gained. Results: Base case pain relief after the treatment was assumed as 20% higher in SBRT. Treatment costs for SBRT and EBRT were $9000 and $1087, respectively. In the base case analysis, SBRT resulted in an ICER of $124,552/QALY gained. In one-way sensitivity analyses, results were most sensitive to variation of the utility of unrelieved pain (range: $89,330 to $592,720/QALY gained); the utility of relieved pain post-treatment and median survival were also sensitive to variation. If median survival is ≥11 months (base case estimate: 9 months), SBRT cost <$100,000/QALY gained. Probabilistic sensitivity analysis demonstrated that SBRT was favored in 30% of model iterations at a WTP threshold of $100,000/QALY gained. Conclusions: SBRT for palliation of vertebral bone metastases is not cost-effective compared to EBRT based upon the ICER analysis with the WTP of $100,000/QALY gained. However, if median survival is ≥11 months, SBRT is economically reasonable, suggesting that selective SBRT usage in patients with longer expected survival may be the most cost-effective approach.

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Wang, Guimei, and Xiaomei Li. "The improvement of XD-MSM friction tester based on Labview." World Journal of Engineering 13, no. 2 (April 8, 2016): 177–80. http://dx.doi.org/10.1108/wje-04-2016-023.

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Purpose With the widespread use and development of automobile, much attention has been paid to its security issues. So to ensure the driving safety, the automobile must be equipped with good braking performance. In the process of braking, the friction from friction pair causes continuous wear and tear of the surface of brake lining and increases the gap between break pairs, until the lining is not being used (Belhocinea et al., 2014); thus, it is very important to detect the lining wear rate. Design/methodology/approach This paper designed the automobile brake friction test wear rate detection system based on Labview. Findings Through the detect data, we find that the automobile brake lining wear rate detection system has higher detect accuracy, in the process of detection, the brake lining without the defects such as cracks and bulges, which shall effect the normal use, the lining has no remarkable scratch to disk friction surface, can completed meet the requirements of users. Originality/value The automobile brake friction test wear rate detecting system adopts the components of USB-9211 DAQ, optoNCDT1700 non-contract high accuracy displacement sensor, in addition the Labview software to complete the functions such as lining wear rate real time detection, data multichannel real time acquisition, display, and storage record, etc., and uses LabSQL to import the detecting data to Microsoft Access database, which can satisfy the demands of various customers. Moreover, the wear rate real time detection can reflect the lining’s wear regulation of different manufacturers and different material and provide a reliable basis for selecting the appropriate lining material and predicting the lining’s lifetime.

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Gerwin, Robert. "Chronic Facial Pain: Trigeminal Neuralgia, Persistent Idiopathic Facial Pain, and Myofascial Pain Syndrome—An Evidence-Based Narrative Review and Etiological Hypothesis." International Journal of Environmental Research and Public Health 17, no. 19 (September 25, 2020): 7012. http://dx.doi.org/10.3390/ijerph17197012.

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Trigeminal neuralgia (TN), the most common form of severe facial pain, may be confused with an ill-defined persistent idiopathic facial pain (PIFP). Facial pain is reviewed and a detailed discussion of TN and PIFP is presented. A possible cause for PIFP is proposed. (1) Methods: Databases were searched for articles related to facial pain, TN, and PIFP. Relevant articles were selected, and all systematic reviews and meta-analyses were included. (2) Discussion: The lifetime prevalence for TN is approximately 0.3% and for PIFP approximately 0.03%. TN is 15–20 times more common in persons with multiple sclerosis. Most cases of TN are caused by neurovascular compression, but a significant number are secondary to inflammation, tumor or trauma. The cause of PIFP remains unknown. Well-established TN treatment protocols include pharmacotherapy, neurotoxin denervation, peripheral nerve ablation, focused radiation, and microvascular decompression, with high rates of relief and varying degrees of adverse outcomes. No such protocols exist for PIFP. (3) Conclusion: PIFP may be confused with TN, but treatment possibilities differ greatly. Head and neck muscle myofascial pain syndrome is suggested as a possible cause of PIFP, a consideration that could open new approaches to treatment.

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Kim, JH, S.-I. Suh, HY Seol, K. Oh, W.-K. Seo, S.-W. Yu, K.-W. Park, and S.-B. Koh. "Regional Grey Matter Changes in Patients With Migraine: A Voxel-Based Morphometry Study." Cephalalgia 28, no. 6 (June 2008): 598–604. http://dx.doi.org/10.1111/j.1468-2982.2008.01550.x.

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We used voxel-based morphometry (VBM) to compare grey matter volume (GMV) between 20 migraine patients (five with aura and 15 without aura) with normal conventional magnetic resonance imaging findings and 33 healthy controls matched for age and sex. A separate analysis was also performed to delineate a possible correlation between the GMV changes and the headache duration or lifetime headache frequency. When compared with controls, migraine patients had significant GMV reductions in the bilateral insula, motor/premotor, prefrontal, cingulate cortex, right posterior parietal cortex, and orbitofrontal cortex ( P < 0.001, uncorrected for multiple comparisons at a voxel level; corrected P < 0.05 after small volume corrections). All regions of the GMV changes were negatively correlated with headache duration and lifetime headache frequency ( P < 0.05, Pearson's correlation test). We found evidence for structural grey matter changes in patients with migraine. Our findings of progressive GMV reductions in relation to increasing headache duration and increasing headache frequency suggest that repeated migraine attacks over time result in selective damage to several brain regions involved in central pain processing.

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Hsu, Chia-Hsun, Yang-Shih Lin, Hsin-Yu Wu, Xiao-Ying Zhang, Wan-Yu Wu, Shui-Yang Lien, Dong-Sing Wuu, and Yeu-Long Jiang. "Deposition of Silicon-Based Stacked Layers for Flexible Encapsulation of Organic Light Emitting Diodes." Nanomaterials 9, no. 7 (July 23, 2019): 1053. http://dx.doi.org/10.3390/nano9071053.

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In this study, inorganic silicon oxide (SiOx)/organic silicon (SiCxHy) stacked layers were deposited by a radio frequency inductively coupled plasma chemical vapor deposition system as a gas diffusion barrier for organic light-emitting diodes (OLEDs). The effects of thicknesses of SiOx and SiCxHy layers on the water vapor transmission rate (WVTR) and residual stress were investigated to evaluate the encapsulation capability. The experimental results showed that the lowest WVTR and residual stress were obtained when the thicknesses of SiOx and SiCxHy were 300 and 30 nm, respectively. Finally, different numbers of stacked pairs of SiOx/SiCxHy were applied to OLED encapsulation. The OLED encapsulated with the six-pair SiOx/SiCxHy exhibited a low turn-on voltage and low series resistance, and device lifetime increased from 7 h to more than 2000 h.

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Fuller-Thomson, Esme, and Bailey Hollister. "Schizophrenia and Suicide Attempts: Findings from a Representative Community-Based Canadian Sample." Schizophrenia Research and Treatment 2016 (2016): 1–11. http://dx.doi.org/10.1155/2016/3165243.

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This study examined factors associated with suicide attempts among those with schizophrenia (n=101) versus those without (n=21,643) in a representative sample of noninstitutionalized Canadians. The lifetime prevalence of suicide attempts among persons with schizophrenia was 39.2% versus 2.8% of nonafflicted individuals. After adjusting for sociodemographics, childhood adversities, substance abuse/dependence, depression/anxiety, and chronic pain, those with schizophrenia had 6 times the odds (OR = 6.47) of attempting suicide. Among persons with schizophrenia, suicide attempts were associated with female gender (OR = 4.59), substance abuse/dependence (OR = 6.31), depression (OR = 4.93), and childhood physical abuse (OR = 5.75). Community-dwelling persons with schizophrenia appear to be at high risk for suicide attempts.

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Fuss, Samantha, M. Gabrielle Pagé, and Joel Katz. "Persistent Pain in a Community-Based Sample of Children and Adolescents: Sex Differences in Psychological Constructs." Pain Research and Management 16, no. 5 (2011): 303–9. http://dx.doi.org/10.1155/2011/534652.

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BACKGROUND: Very few studies have investigated the psychological factors associated with the pain experiences of children and adolescents in community samples.OBJECTIVES: To examine the lifetime prevalence of, and psychological variables associated with, persistent pain in a community sample of children and adolescents, and to explore differences according to sex, age and pain history.METHODS: Participants completed the Childhood Anxiety Sensitivity Index (CASI), the Child Pain Anxiety Symptoms Scale (CPASS), the Multidimensional Anxiety Scale for Children-10 (MASC-10), the Pain Catastrophizing Scale for Children (PCS-C) and a pain history questionnaire that assessed chronicity and pain frequency. After research ethics board approval, informed consent/assent was obtained from 1022 individuals recruited to participate in a study conducted at the Ontario Science Centre (Toronto, Ontario).RESULTS: Of the 1006 participants (54% female, mean [± SD] age 11.6±2.7 years) who provided complete data, 27% reported having experienced pain that lasted for three months or longer. A 2×2×2 (pain history, age and sex) multivariate ANOVA was conducted, with the total scores on the CASI, the CPASS, the MASC-10 and the PCS-C as dependent variables. Girls with a history of persistent pain expressed higher levels of anxiety sensitivity (P<0.001) and pain catastrophizing (P<0.001) than both girls without a pain history and boys regardless of pain history. This same pattern of results was found for anxiety and pain anxiety in the older, but not the younger, age group.CONCLUSIONS: Boys and girls appear to differ in terms of how age and pain history relate to the expression of pain-related psychological variables. Given the prevalence of persistent pain found in the study, more research is needed regarding the developmental implications of persistent pain in childhood and adolescence.

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Romanov, S. I., O. A. Botvinova, E. A. Timakov, L. A. Chizhova, and Yu T. Panov. "Development of a polyurea-based composition with an extended life span." Fine Chemical Technologies 16, no. 2 (May 25, 2021): 176–83. http://dx.doi.org/10.32362/2410-6593-2021-16-2-176-183.

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Objectives. Improvement of the technology for obtaining polymer-sprayed coatings based on polycarbodiimides (polyureas) with high chemical, hydrolytic, and abrasive resistance and improved physical and mechanical properties, as well as obtainment of polyurea compositions with a lifetime of at least 5 min without loss performance characteristics (i.e., “hand-applied” polyureas) suitable for repair of coatings already in use.Methods. The reaction rate between isocyanate and amino groups is almost a hundred times higher than that between isocyanate and hydroxyl groups, necessitating the use of special highperformance and high-pressure installations equipped with self-cleaning mixing chambers and heating of components. The following are determined from the obtained materials: strength, elongation at break according to the standard method, Taber abrasion, and Shore hardness.Results. Three methods of slowing down the reaction are investigated: 1) the synthesis of prepolymers with the content of NCO groups from 10.5% to 18%; 2) the addition of a plasticizer into the prepolymer in the amount of 1–10 mass parts; and 3) the introduction of polyesters into the composition and radiation of the so-called “hybrid” systems. When using 14% polyesters with a molecular weight of 2000 Da, only “hybrid” systems make it possible to obtain compositions with a lifetime of more than 5 min. At the same time, the tensile strength decreases by 20%, and the abrasion increases by 40%; however, such “hybrid” systems have a higher adhesion force and are cheaper than pure polyureas, allowing them to be used as “repair” systems.Conclusions. The developed composition and technology of applying “hybrid” systems allow for the repair of existing coatings without using specialized devices. “Manual” polyurea is easy to use and does not require special training.

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Mattsson, P., K. Svärdsudd, Po Lundberg, and C.-E. Westerberg. "The Prevalence of Migraine in Women Aged 40–74 Years: A Population-Based Study." Cephalalgia 20, no. 10 (December 2000): 893–99. http://dx.doi.org/10.1046/j.1468-2982.2000.00133.x.

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The objective of this study was to investigate the age-dependence of the prevalence and characteristics of migraine headache and migraine visual aura. A neurologist interviewed 728 women attending a mammography screening programme. International Headache Society (IHS) criteria were used. The lifetime prevalence of migraine headache was 31.5% and the 1-year prevalence 18.0%. The magnitude of the decline of the prevalence of active (one or more attacks in the previous year) migraine headache was estimated to 50% per decade. The prevalence of active migraine visual aura was 3.8%. This did not vary by age. Except for the pain intensity and the presence of nausea, other characteristics and concomitant symptoms did not change with age. Active migraine headache and migraine visual aura in middle-aged and older women are common and modified differently by age. We suggest that the decline of prevalence of active migraine headache with age is caused by a decrease in pain intensity.

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Sobolewski, A. L., W. Domcke, and C. Hattig. "Tautomeric selectivity of the excited-state lifetime of guanine/cytosine base pairs: The role of electron-driven proton-transfer processes." Proceedings of the National Academy of Sciences 102, no. 50 (December 5, 2005): 17903–6. http://dx.doi.org/10.1073/pnas.0504087102.

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Hodgins, Caroline, James Stannah, Salome Kuchukhidze, Lycias Zembe, Jeffrey W. Eaton, Marie-Claude Boily, and Mathieu Maheu-Giroux. "Population sizes, HIV prevalence, and HIV prevention among men who paid for sex in sub-Saharan Africa (2000–2020): A meta-analysis of 87 population-based surveys." PLOS Medicine 19, no. 1 (January 25, 2022): e1003861. http://dx.doi.org/10.1371/journal.pmed.1003861.

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Background Key populations, including sex workers, are at high risk of HIV acquisition and transmission. Men who pay for sex can contribute to HIV transmission through sexual relationships with both sex workers and their other partners. To characterize the population of men who pay for sex in sub-Saharan Africa (SSA), we analyzed population size, HIV prevalence, and use of HIV prevention and treatment. Methods and findings We performed random-effects meta-analyses of population-based surveys conducted in SSA from 2000 to 2020 with information on paid sex by men. We extracted population size, lifetime number of sexual partners, condom use, HIV prevalence, HIV testing, antiretroviral (ARV) use, and viral load suppression (VLS) among sexually active men. We pooled by regions and time periods, and assessed time trends using meta-regressions. We included 87 surveys, totaling over 368,000 male respondents (15–54 years old), from 35 countries representing 95% of men in SSA. Eight percent (95% CI 6%–10%; number of surveys [Ns] = 87) of sexually active men reported ever paying for sex. Condom use at last paid sex increased over time and was 68% (95% CI 64%–71%; Ns = 61) in surveys conducted from 2010 onwards. Men who paid for sex had higher HIV prevalence (prevalence ratio [PR] = 1.50; 95% CI 1.31–1.72; Ns = 52) and were more likely to have ever tested for HIV (PR = 1.14; 95% CI 1.06–1.24; Ns = 81) than men who had not paid for sex. Men living with HIV who paid for sex had similar levels of lifetime HIV testing (PR = 0.96; 95% CI 0.88–1.05; Ns = 18), ARV use (PR = 1.01; 95% CI 0.86–1.18; Ns = 8), and VLS (PR = 1.00; 95% CI 0.86–1.17; Ns = 9) as those living with HIV who did not pay for sex. Study limitations include a reliance on self-report of sensitive behaviors and the small number of surveys with information on ARV use and VLS. Conclusions Paying for sex is prevalent, and men who ever paid for sex were 50% more likely to be living with HIV compared to other men in these 35 countries. Further prevention efforts are needed for this vulnerable population, including improved access to HIV testing and condom use initiatives. Men who pay for sex should be recognized as a priority population for HIV prevention.

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Kochoyan, Michel, Jean Louis Leroy, and Maurice Guéron. "Proton exchange and base-pair lifetimes in a deoxy-duplex containing a purine-pyrimidine step and in the duplex of inverse sequence." Journal of Molecular Biology 196, no. 3 (August 1987): 599–609. http://dx.doi.org/10.1016/0022-2836(87)90036-2.

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Stafford, Clara Alexandra, Bobby Stojanoski, Conor Wild, and Adrian Owen. "The association between a history of self-reported concussion and response inhibition: a population-based study." Neurology 93, no. 14 Supplement 1 (September 30, 2019): S2.3—S3. http://dx.doi.org/10.1212/01.wnl.0000580844.16446.88.

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ObjectiveWe investigated the long-term cognitive effects of concussion in almost 20,000 members of the general population, using tests that are known to be sensitive to small changes in performance.BackgroundConcussions are the most common type of mild traumatic brain injury, with clinical symptoms such as headaches, dizziness, and nausea, persisting for months post-injury. Despite a growing understanding of the severity and duration of these symptoms, very little is known about the long-term effects of concussion on higher level cognitive functioning and emotional lability.Design/MethodsWe asked 19,261 participants to complete a demographic questionnaire as well as the Cambridge Brain Sciences (CBS) cognitive battery. We divided our sample into two groups: those reporting at least one concussion in their lifetime (post-concussion) and those reporting no concussions in their lifetime (non-concussed). We compared the performance of the two groups on the 12 CBS tasks, as well as on four non-cognitive variables measuring levels of social contact, anxiety, depression, and concentration difficulties.ResultsWe found that post-concussion individuals performed significantly worse on a modified Stroop task that measures aspects of response inhibition, but were no worse on any other cognitive measure, including short-term memory, reasoning, and verbal abilities. Crucially, performance profiles of the post-concussion individuals indicated that they made more errors on trials that involved an incongruent colour/word pair. Beyond measures of cognition, we found that post-concussion participants also reported higher levels of anxiety, depression, and trouble concentrating when compared to the non-concussed group. The number of reported concussions also predicted task scores on this task only.ConclusionsOur results suggest that sustaining a concussion is not associated with long-term global effects on cognition. Those who report at least one concussion appear to have a modest, but statistically significant deficit of response inhibition. This impairment seems to be related to the number of concussions reported.

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Taylor, Rebecca J., and Rod S. Taylor. "Spinal cord stimulation for failed back surgery syndrome: A decision-analytic model and cost-effectiveness analysis." International Journal of Technology Assessment in Health Care 21, no. 3 (July 2005): 351–58. http://dx.doi.org/10.1017/s0266462305050464.

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Objectives:The aim of this study was to develop a decision-analytic model to assess the cost-effectiveness of spinal cord stimulation (SCS), relative to nonsurgical conventional medical management (CMM), for patients with failed back surgery syndrome (FBSS).Methods:A decision tree and Markov model were developed to synthesize evidence on both health-care costs and outcomes for patients with FBSS. Outcome data of SCS and CMM were sourced from 2-year follow-up data of two randomized controlled trials (RCTs). Treatment effects were measured as levels of pain relief. Short- and long-term health-care costs were obtained from a detailed Canadian costing study in FBSS patients. Results are presented as incremental cost per quality adjusted life year (QALY) and expressed in 2003 Euros. Costs were discounted at 6 percent and outcomes at 1.5 percent.Results:Over the lifetime of the patient, SCS was dominant (i.e., SCS is cost-saving and gives more health gain relative to CMM); a finding that was robust across sensitivity analyses. At a 2-year time horizon, SCS gave more health gain but at an increased cost relative to CMM. Given the uncertainty in effectiveness and cost parameters, the 2-year cost-effectiveness of SCS ranged from €30,370 in the base case to €63,511 in the worst-case scenario.Conclusions:SCS was found to be both more effective and less costly than CMM, over the lifetime of a patient. In the short-term, although SCS is potentially cost-effective, the model results are highly sensitive to the choice of input parameters. Further empirical data are required to improve the precision in the estimation of short-term cost-effectiveness.

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Henrique Dias, Eduardo, Gelson Tiago Dos Santos Tavares da Silv, Osmando Ferreira Lopes, and Caue Ribeiro. "Preparation of Bi-based heterostructures through the one-pot method with the potential to photocatalytic applications." Journal of Experimental Techniques and Instrumentation 4, no. 01 (December 15, 2020): 39–51. http://dx.doi.org/10.30609/jeti.v4i01.11438.

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This paper describes a facile one-pot method to obtain Bi-based heterostructures by calcination process and evaluate the physical-chemical properties. The increase in the temperature treatment changed the sample’s phase crystalline, the synthesis method proposed was able to obtain (BiO)2CO3, α-Bi2O3, and β-Bi2O3 pure phases and (BiO)2CO3/α-Bi2O3 and α-Bi2O3/β-Bi2O3 heterostructures. Additionally, the annealing temperature also influences the morphology, optical, and photocatalytic properties. The temperature increases decreased the sample’s bandgap, and the above 350ºC, the samples became active under visible radiation. The photocatalytic performance of the samples was evaluated under UV and visible radiation on the MB degradation, it was observed that under UV radiation, the (BiO)2CO3 phase exhibited higher performance than the Bi2O3 phase. Therefore, we can confirm that the increases in the temperature harmed the photocatalytic performance under UV radiation. On the other hand, synthesized samples above 300°C showed the best performance under visible radiation, due to the bandgap reduction and the electron/hole pair lifetime increasing.

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Bell, Cathrine, Mette K. Nielsen, Mette A. Neergaard, Mai-Britt Guldin, and Anders B. Jensen. "Remaining Lifetime After Recognition of Terminal Illness Depends on Diagnosis: A Nationwide Population-Based Cohort Study." Journal of Pain and Symptom Management 53, no. 1 (January 2017): 116–23. http://dx.doi.org/10.1016/j.jpainsymman.2016.08.002.

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Journal articles on the topic 'Base pair lifetime'

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