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Psychological bias towards, or away from, prior measurements or theory predictions is an intrinsic threat to any data analysis. While various methods can be used to try to avoid such a bias, e.g. actively avoiding looking at the result, only data blinding is a traceable and trustworthy method that can circumvent the bias and convince a public audience that there is not even an accidental psychological bias. Data blinding is nowadays a standard practice in particle physics, but it is particularly difficult for experiments searching for the neutron electric dipole moment (nEDM), as several cross measurements, in particular of the magnetic field, create a self-consistent network into which it is hard to inject a false signal. We present an algorithm that modifies the data without influencing the experiment. Results of an automated analysis of the data are used to change the recorded spin state of a few neutrons within each measurement cycle. The flexible algorithm may be applied twice (or more) to the data, thus providing the option of sequentially applying various blinding offsets for separate analysis steps with independent teams. The subtle manner in which the data are modified allows one subsequently to adjust the algorithm and to produce a re-blinded data set without revealing the initial blinding offset. The method was designed for the 2015/2016 measurement campaign of the nEDM experiment at the Paul Scherrer Institute. However, it can be re-used with minor modification for the follow-up experiment n2EDM, and may be suitable for comparable projects elsewhere.
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We present the result of an experiment to measure the electric dipole moment (EDM) of the neutron at the Paul Scherrer Institute using Ramsey's method of separated oscillating magnetic fields with ultracold neutrons. Our measurement stands in the long history of EDM experiments probing physics violating time-reversal invariance. The salient features of this experiment were the use of a ^{199}Hg comagnetometer and an array of optically pumped cesium vapor magnetometers to cancel and correct for magnetic-field changes. The statistical analysis was performed on blinded datasets by two separate groups, while the estimation of systematic effects profited from an unprecedented knowledge of the magnetic field. The measured value of the neutron EDM is d_{n}=(0.0±1.1_{stat}±0.2_{sys})×10^{-26} e.cm.
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The performance gain-oriented nanostructurization has opened a new pathway for tuning mechanical features of solid matter vital for application and maintained performance. Simultaneously, the mechanical evaluation has been pushed down to dimensions way below 1 µm. To date, the most standard technique to study the mechanical properties of suspended 2D materials is based on nanoindentation experiments. In this work, by means of micro-Brillouin light scattering we determine the mechanical properties, that is, Young modulus and residual stress, of polycrystalline few nanometers thick MoS2 membranes in a simple, contact-less, nondestructive manner. The results show huge elastic softening compared to bulk MoS2, which is correlated with the sample morphology and the residual stress.
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Rapeseed proteins have been considered as being poorly digestible in the gut of non-ruminants. The aim of the study was to assess the digestibility of napin and cruciferin in ileal digesta of broiler chickens, testing sixteen samples of rapeseed co-products with protein levels ranging from 293 g/kg to 560 g/kg dry matter. Each sample was included into a semi-synthetic diet at a rate of 500 g/kg and evaluated with broiler chickens in a randomised design. Dietary and ileal digesta proteins were extracted and identified by gel-based liquid chromatography-tandem mass spectrometry (LC-MS/MS). Three isomers of napin (a 2S albumin) and nine cruciferins (an 11S globulin) were identified in the rapeseed co-products, whereas six endogenous enzymes such as trypsin (I-P1, II-P29), chymotrypsin (elastase and precursor), carboxypeptidase B and α-amylase were found in the ileal digesta. It is concluded that as none of the rapeseed proteins were detected in the ileal digesta, rapeseed proteins can be readily digested by broiler chickens, irrespective of the protein content in the diet.
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Albuminas 2S de Plantas/metabolismo , Ração Animal/análise , Antígenos de Plantas/metabolismo , Brassica rapa/química , Galinhas/metabolismo , Proteínas de Armazenamento de Sementes/metabolismo , Albuminas 2S de Plantas/química , Fenômenos Fisiológicos da Nutrição Animal , Animais , Antígenos de Plantas/química , Dieta/veterinária , Masculino , Proteínas de Armazenamento de Sementes/químicaRESUMO
We present a magnetometer based on optically pumped Cs atoms that measures the magnitude and direction of a 1 µT magnetic field. Multiple circularly polarized laser beams were used to probe the free spin precession of the Cs atoms. The design was optimized for long-time stability and achieves a scalar resolution better than 300 fT for integration times ranging from 80 ms to 1000 s. The best scalar resolution of less than 80 fT was reached with integration times of 1.6 to 6 s. We were able to measure the magnetic field direction with a resolution better than 10 µrad for integration times from 10 s up to 2000 s.
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We describe a spin-echo method for ultracold neutrons (UCNs) confined in a precession chamber and exposed to a |B0|=1 µT magnetic field. We have demonstrated that the analysis of UCN spin-echo resonance signals in combination with knowledge of the ambient magnetic field provides an excellent method by which to reconstruct the energy spectrum of a confined ensemble of neutrons. The method takes advantage of the relative dephasing of spins arising from a gravitationally induced striation of stored UCNs of different energies, and also permits an improved determination of the vertical magnetic-field gradient with an exceptional accuracy of 1.1 pT/cm. This novel combination of a well-known nuclear resonance method and gravitationally induced vertical striation is unique in the realm of nuclear and particle physics and should prove to be invaluable for the assessment of systematic effects in precision experiments such as searches for an electric dipole moment of the neutron or the measurement of the neutron lifetime.
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Gravitação , Modelos Teóricos , Nêutrons , Temperatura Baixa , CinéticaRESUMO
The effect of everlasting pea in combination with wheat on physical properties and microstructure of extrudates were studied. The share of everlasting pea (Lathyrus sativus) was variable, at 35, 50 and 65 %, respectively. The everlasting pea-wheat mixtures were moistened to the required level (18, 21, and 24 %), homogenized, conditioned and extruded in twin-screw extruder with counter-rotating conical screws. All of the obtained extrudates were characterised by a slow degree of radial expansion and high specific density. The Pearson correlation analysis indicated a statistically significant linear Pearson correlation (p < 0.05) between chemical compositions of the blends and physical properties of the extrudates. The expansion ratio increased as the concentration of the fibers and proteins increased, while specific density and hardness decreased. Inverse relationship was observed for crude fat. The microstructure of the extrudates was determined by both the moisture of the blend and the process temperature. The differences observed in the size, number of air cells and in the cell wall shapes and thickness indicate possibilities of the modification of physical properties of everlasting pea-wheat extrudates. The extrudates produced from everlasting pea-wheat blends (50:50) at higher barrel temperature (110/140/180/170/130 °C) were characterised by more numerous air cells of smaller diameters. Increasing moisture content of extruded blends results in extrudates with a higher porosity. No significant effect was shown in the chemical compositions on the level of metal contamination in the extrudates. The application of a counter-rotating twin-screw extrusion-cooker in the study permitted the production of compact, hard everlasting pea-wheat extrudates for use in vegetarian lunch dishes.
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This paper presents the results of an investigation into the processes controlling development of a cryo-conditioned rock coast system in Hornsund, Svalbard. A suite of nested geomorphological and geophysical methods have been applied to characterise the functioning of rock cliffs and shore platforms influenced by lithological control and geomorphic processes driven by polar coast environments. Electrical resistivity tomography (ERT) surveys have been used to investigate permafrost control on rock coast dynamics and reveal the strong interaction with marine processes in High Arctic coastal settings. Schmidt hammer rock tests, demonstrated strong spatial control on the degree of rock weathering (rock strength) along High Arctic rock coasts. Elevation controlled geomorphic zones are identified and linked to distinct processes and mechanisms, transitioning from peak hardness values at the ice foot through the wave and storm dominated scour zones to the lowest values on the cliff tops, where the effects of periglacial weathering dominate. Observations of rock surface change using a traversing micro-erosion meter (TMEM) indicate that significant changes in erosion rates occur at the junction between the shore platform and the cliff toe, where rock erosion is facilitated by frequent wetting and drying and operation of nivation and sea ice processes (formation and melting of snow patches and icefoot complexes). The results are synthesised to propose a new conceptual model of High Arctic rock coast systems, with the aim of contributing towards a unifying concept of cold region landscape evolution and providing direction for future research regarding the state of polar rock coasts.
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Four experiments were carried out to study the possible differences in metabolizable energy (ME) of meals (RSM) or expeller meals (RSE) from double-low rapeseed (Expt. 1), the influence of processing on ME (Expt. 2) and on relative phosphorus (P) bioavailability (Expt. 3) in RSM, and effect of RSM inclusion on growth performance of broilers (Expt. 4). For Expt. 1, diets with 300 g/kg RSM from 11 RSM and 4 RSE varieties were fed to broilers from d 14 to 21, with excreta collection on d 19 to 21. Each treatment had 8 replicates and 3 birds per replicate. Energy metabolizability of RSM of a specialized high glucosinolate variety (V275OL) was greater (P < 0.05) than all the other varieties. In Expt. 2, two RSM varieties were processed with mild or conventional processing condition. There were no variety effects on ME, but ME and MEn were greater (P < 0.01) for RSM processed by mild processing condition. In Expt. 3, P bioavailability of RSM was determined, relative to MSP, using growth performance and tibia ash as responses. Phosphorus relative bioavailability values were greater (P < 0.05) in RSM of DK Cabernet variety processed using the mild processing condition. In Expt. 4, two RSM varieties were added to wheat-soybean meal-based diet at the rates of 50, 100, 150, or 200 g/kg and fed to broilers from d 0 to 42. Inclusion of 150 and 200 g/kg of RSM resulted in reduced weight gain and increased feed conversion ratio (FCR) compared (P < 0.01) with the lower inclusion levels during the starter phase. For the entire trial (d 0 to 42), weight gain was greater (P < 0.01) for birds receiving diets with RSM from PR46W21 variety. It was concluded from the experiments that apart from the residual ether extract content, variety differences had no impact on ME of RSM, conventional processing reduced ME and relative bio-availability of P; and that the maximum level of RSM inclusion depends on maximum growth performance level desired.
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Brassica napus/química , Galinhas/crescimento & desenvolvimento , Galinhas/metabolismo , Valor Nutritivo , Fósforo/metabolismo , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Disponibilidade Biológica , Dieta/veterinária , Suplementos Nutricionais/análise , Metabolismo Energético/efeitos dos fármacos , Masculino , Distribuição AleatóriaRESUMO
An inherent element of research and applications in photonics is a beam of light. In magnonics, which is the magnetic counterpart of photonics, where spin waves are used instead of electromagnetic waves to transmit and process information, the lack of a beam source limits exploration. Here, we present an approach enabling generation of narrow spin wave beams in thin homogeneous nanosized ferromagnetic films by microwave current. We show that the desired beam-type behavior can be achieved with the aid of a properly designed coplanar waveguide transducer generating a nonuniform microwave magnetic field. We test this idea using micromagnetic simulations, confirming numerically that the resulting spin wave beams propagate over distances of several micrometers. The proposed approach requires neither inhomogeneity of the ferromagnetic film nor nonuniformity of the biasing magnetic field. It can be generalized to different magnetization configurations and yield multiple spin wave beams of different width at the same frequency.
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OBJECTIVES: Although leukocyte elastase is suspected to be involved in the damage of vein wall during chronic venous disease, the equilibrium between this protease and its inhibitor, alpha1-antitrypsin, has not yet been evaluated. The aim of the present study was to determine the relationship between leukocyte elastase and alpha1-antitrypsin, in the blood of patients with chronic venous disease. PATIENTS AND METHODS: The concentration and the activity of leukocyte elastase along with the activity of alpha1-antitrypsin were evaluated in the blood of 55 chronic venous disease patients. The results were compared with those obtained in 33 healthy age and sex-matched volunteers. RESULTS: A significant decrease in the leukocyte elastase activity that correlated with an increased alpha1-antitrypsin activity was observed in the serum of patients with mild clinical symptoms of chronic venous disease. CONCLUSIONS: The results of the study did not confirm a hypothesis about an important role of proteolytic activity of leukocyte elastase in the vein wall injury mechanism. They show that the leukocyte elastase-alpha1-antitrypsin balance is rather shifted toward antiprotease activity, especially in an early stage of chronic venous disease.
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Elastase de Leucócito/sangue , Doenças Vasculares/sangue , alfa 1-Antitripsina/sangue , Adulto , Idoso , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
An 18-year monitoring record (1978-1995) of dissolved oxygen within a region having hypoxia (dissolved oxygen less than 2 mgl(-1)) in the bottom layer was examined to describe seasonal and annual trends. The monitoring location was near or within a well-described summer hypoxic zone whose size has been up to 20,000 km(2). The monitoring data were used to hindcast the size of the hypoxic zone for before consistent shelfwide surveys started, and to predict it for 1989, when a complete shelfwide survey was not made. The concentration of total Kjeldahl nitrogen (TKN) in surface waters and concentration of bottom water oxygen were directly related, as anticipated if organic loading from surface to bottom was from in situ processes. The TKN data were used to develop a predictive relationship that suggested there was no substantial hypoxia before the 1970s, which was before nitrate flux from the Mississippi River to the Gulf of Mexico began to rise. The peak frequency in monthly hypoxic events is two to three months after both the spring maximum in discharge and nitrate loading of the Mississippi River. These results support the conclusion that persistent, large-sized summer hypoxia is a recently-developed phenomenon that began in the 1970s or early 1980s.
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Modelos Teóricos , Oxigênio/análise , Água do Mar/química , Monitoramento Ambiental , Previsões , Louisiana , Mississippi , Estudos Retrospectivos , Estações do AnoRESUMO
For highly sensitive magnetic measurements, e.g., a measurement of the neutron electric dipole moment (EDM), the magnetic field has to be stable in time on a level below picoTesla. One of several measures we employ to achieve this uses an external field coil system which can stabilize the ambient external field at a predefined value. Here we report on the construction and characterization of such a system in the magnetic test facility at PSI. The system actively stabilizes the field along the axis of the EDM experiment by means of four coils in a Helmholtz-like configuration. Additional coils serve to compensate for transverse ambient field components. Because of the long integration times in the EDM experiment (about 100 s or more) only slow disturbances have to be corrected for. The performance of the system has been measured using static and moving magnetic sources and suppression factors in excess of 200 have been observed.
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Solid deuterium (sD2) will be used for the production of ultra-cold neutrons (UCN) in a new generation of UCN sources. Scattering cross sections of UCN in sD2 determine the source yield but until now have not been investigated. We report first results from transmission and scattering experiments with cold, very cold and ultra-cold neutrons on sD2 along with light transmission and Raman scattering studies showing the influence of the sD2 crystal properties.
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The problem addressed in this paper is concerned with DNA sequencing by hybridization. An algorithm is proposed that solves a computational phase of this approach in the presence of both positive and negative errors resulting from the hybridization experiment. No a priori knowledge of the nature and source of these errors is required. An extensive set of computational experiments showed that the algorithm behaves surprisingly well if only positive errors appear. The general case, where positive and negative errors occur, can be also solved satisfactorily for an error rate up to 10%.
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Algoritmos , Sequência de Bases , DNA/química , DNA/genética , Biologia Computacional/métodos , Modelos Estatísticos , Reprodutibilidade dos TestesRESUMO
An algorithm is proposed to provide the tool for an automatic resonance assignment of 2D-NOESY spectra of RNA duplexes. The algorithm, based on a certain subproblem of the Hamiltonian path, reduces a number of possible connections between resonances within aromatic and anomeric region of 2D-NOESY spectra. Appropriate pathways between H6/H8 and H1' resonances were obtained by subsequent implementation of experimental data as limiting factors. Predictive power of the algorithm was tested on both experimental and simulated data for RNA and DNA duplexes.
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Algoritmos , Ressonância Magnética Nuclear Biomolecular , Ácidos Nucleicos Heteroduplexes/química , Oligodesoxirribonucleotídeos/química , Oligorribonucleotídeos/química , Software , Simulação por Computador , Conformação de Ácido NucleicoRESUMO
OBJECTIVE: To investigate and compare mechanisms controlling the development of antisperm antibodies in situations with different status of active immunosuppression. DESIGN: Antibody activity against human sperm was analyzed by immunosorbent assays (ELISA) in sera samples of prepubertal boys and in circulation of sensitized immunocompromised mice. SETTING: Procedures were performed in a university laboratory. PATIENT(S): Prepubertal healthy boys and patients with testicular failures. INTERVENTION(S): Blood was collected from healthy individuals and from patients with diagnosed testicular pathology; antisperm antibodies were rechecked after surgical intervention (orchidopexia or removal of the pathological gonad). MAIN OUTCOME MEASURE(S): Antisperm antibodies in quantitative ELISA. RESULT(S): Significant antibody activity to finally differentiated human sperm was detected in sera samples from prepubertal boys with testicular failures (cryptorchid or mobile testis), especially in individuals with both pathological gonads. "Naive" human lymphocytes deposited to peritoneal cavity of immunocompromised mice did not respond to in situ challenge with sperm antigens. CONCLUSION(S): High antisperm antibody levels in prepubertal boys may suggest low immunosuppressive activity at this age. This situation may influence future fertility status of these individuals. Immunocompromised mice effectively prevented humoral response to sperm antigens suggesting different mechanism than T suppressor cell activity.
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Autoanticorpos/sangue , Espermatozoides/imunologia , Adolescente , Animais , Antígenos/imunologia , Criança , Pré-Escolar , Criptorquidismo/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Masculino , Camundongos , Camundongos SCID , Puberdade , Doenças Testiculares/imunologiaRESUMO
To study olfactory communication in humans, 100 undergraduates ranging from age 18 to 45 yr. wore freshly washed, identical T-shirts continuously for 24 hr. During this time, the participants did not bathe or shower or apply any scent producing substance to their bodies, i.e., deodorants, perfumes. Upon retrieval, each shirt was placed in an identical brown bag. In groups of 10, each participant attempted to identify the T-shirt he had worn the previous 24 hr. The task was administered separately for each individual so that no participants knew the choice by a previous colleague. Analysis shows that the participants were able to identify correctly their own shirts on the first try three-quarters of the time. Furthermore, sex, age, smoking habit of the participant, and menstrual cycle phase in the women were factors in successful outcomes.
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Odorantes , Autoimagem , Olfato , Adolescente , Adulto , Atenção , Aprendizagem por Discriminação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fumar/psicologiaRESUMO
Polarographic (DPP) activity of 6-benzyl-2-thiouracil (6-benzyl-2-mercapto-4-pyrimidinol, BTU) has been examined in a wide range of pH values and it has been discovered that the number and the height of observed peaks depends on composition of supporting electrolyte and concentration of the thiol. Two different types of signals can be obtained. One of them is controlled by diffusion while the other by adsorption. The procedure for the determination of BTU in pure samples in 0.1 mol.dm-3 sodium hydroxide solution has been worked out. The measurements can be performed in a range 3.10(-4)-3.10(-3) mol.dm-3 of BTU. The detection limit is however lower and reaches 5.10(-6) mol.dm-3. The method has been used in the determination of BTU in an antithyroid drug Basdène.
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Antitireóideos/análise , Tiouracila/análise , Calibragem , Concentração de Íons de Hidrogênio , Polarografia , Comprimidos , Tiouracila/análogos & derivadosRESUMO
Spermatozoa are immunogenic and may induce an immune response in reproductive compartments. There have been controversies concerning the effect of naturally existing antisperm antibodies on fertility of males and females. It is known, that men or women suffering from unexplained infertility have often antisperm antibodies in their urogenital secretions and/or serum. Systemic and local immune responses to sperm antigens differ between each other and they may differently affect the fertilisation process. Physiologically, females are protected from an immune response against "foreign", spermatozoal antigens. Nevertheless under local pathological conditions antisperm antibodies can be induced and may interfere with fertilisation.