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OBJECTIVES: The assessment of pulmonary single-breath diffusing capacity is a frequently performed diagnostic procedure and considered as an important tool in medical surveillance examinations of pulmonary diseases.The aim of this study was to establish reference equations for pulmonary single-breath diffusing capacity parameters in a representative adult-population across a wide age range and to compare the normative values from this sample with previous ones. METHODS: Diffusing capacity measurement was carried out in 3566 participants (1811 males) of a cross-sectional, population-based survey ("Study of Health in Pomerania - SHIP"). RESULTS: Individuals with cardiopulmonary disorders and current smoking habits were excluded, resulting in 1786 healthy individuals (923 males), aged 20â-â84 years. Prediction equations for both sexes were established by quantile regression analyses, taking into consideration the influence of age, height, weight and former smoking. CONCLUSION: The study provides a novel set of prediction equations for pulmonary single-breath diffusing capacity in an adult Caucasian population. The results are comparable to previously reported equations, underline their importance and draw attention to the need for up-to-date reference equations that adequately take into account both the subjects' origin, age, anthropometric characteristics and the equipment used.
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Enfermedades Pulmonares , Capacidad de Difusión Pulmonar , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Fumar , Adulto JovenRESUMEN
A combination of phenomenological analysis and Mössbauer spectroscopy experiments on the tetragonal Fe(1+y)Te system indicates that the magnetic ordering transition in compounds with higher Fe excess, y≥0.11, is unconventional. Experimentally, a liquidlike magnetic precursor with quasistatic spin order is found from significantly broadened Mössbauer spectra at temperatures above the antiferromagnetic transition. The incommensurate spin-density wave order in Fe(1+y)Te is described by a magnetic free energy that violates the weak Lifshitz condition in the Landau theory of second-order transitions. The presence of multiple Lifshitz invariants provides the mechanism to create multidimensional, twisted, and modulated solitonic phases.
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Copyleft AI with Trusted Enforcement (CAITE) can support an adaptable so ft law approach for ethics in AI.
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The intermetallic compound Eu[Formula: see text]In[Formula: see text]Sb[Formula: see text], an antiferromagnetic material with nonsymmorphic crystalline structure, is investigated by magnetic, electronic transport and specific heat measurements. Being a Zintl phase, insulating behavior is expected. Our thermodynamic and magnetotransport measurements along different crystallographic directions strongly indicate polaron formation well above the magnetic ordering temperatures. Pronounced anisotropies of the magnetic and transport properties even above the magnetic ordering temperature are observed despite the Eu[Formula: see text] configuration which testify to complex and competing magnetic interactions between these ions and give rise to intricate phase diagrams discussed in detail. Our results provide a comprehensive framework for further detailed study of this multifaceted compound with possible nontrivial topology.
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To simultaneously perform magnetization and magnetostriction measurements in high magnetic fields, a miniaturized device was developed that combines an inductive magnetometer with a capacitive dilatometer and, therefore, it is called "dilamagmeter." This combination of magnetic and magnetoelastic investigations is a new step to a complex understanding of solid state properties. The whole system can be mounted in a 12 mm clear bore of any cryostat usually used in nondestructive pulsed high field magnets. The sensitivity of both methods is about 10(-5) A m(2) for magnetization and 10(-5) relative changes in length for striction measurements. Measurements on a GdSi single crystal, which are corrected by the background signal of the experimental setup, agree well with the results of steady field experiments. All test measurements, which are up until now performed in the temperature range of 4-100 K, confirm the perfect usability and high stability in pulsed fields up to 50 T with a pulse duration of 10 ms.
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Rare-earth (R)-iron alloys are a backbone of permanent magnets. Recent increase in price of rare earths has pushed the industry to seek ways to reduce the R-content in the hard magnetic materials. For this reason strong magnets with the ThMn12 type of structure came into focus. Functional properties of R(Fe,T)12 (T-element stabilizes the structure) compounds or their interstitially modified derivatives, R(Fe,T)12-X (X is an atom of hydrogen or nitrogen) are determined by the crystal-electric-field (CEF) and exchange interaction (EI) parameters. We have calculated the parameters using high-field magnetization data. We choose the ferrimagnetic Tm-containing compounds, which are most sensitive to magnetic field and demonstrate that TmFe11Ti-H reaches the ferromagnetic state in the magnetic field of 52 T. Knowledge of exact CEF and EI parameters and their variation in the compounds modified by the interstitial atoms is a cornerstone of the quest for hard magnetic materials with low rare-earth content.
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We report the attainment of the ferromagnetic state in an interstitially modified heavy rare-earth-iron intermetallic compound in an external magnetic field. The starting composition is RE2Fe17, which is the RE-Fe binary richest in iron. We concentrate on the Tm-Fe compound, which is the most sensitive to magnetic field. The maximum possible amount of hydrogen (5 at.H/f.u.) is inserted into a Tm2Fe17 single crystal. We demonstrate that in a magnetic field of 57 T Tm2Fe17H5 reaches the ferromagnetic state with an enviably high polarization of 2.25 T.
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This 3-yr study examined the use of two different apple, Malus domestica Borkhausen, pest management programs based on horticultural mineral oil. Whereas oil provided some additional control of codling moth, Cydia pomonella (L.), when targeting eggs of both generations (Oil/Direct Pest program, typically six applications per season), the additional benefit was difficult to detect when densities were high. With moderate densities, oil reduced the number of fruit infestations, but not stings (unsuccessful entries). There also were some measurable benefits to leafroller, Pandemis pyrusana Kearfott control. Oil was most useful, however, in suppression of secondary pests. White apple leafhopper, Typhlocyba pomaria McAtee, was the primary target of oil applications in the Oil/Indirect Pest program (typically three applications per season). However, leafhopper suppression in the Oil/Direct Pest program was generally greater because of the higher number of applications. Phytophagous tetranychid and eriophyid mites also were suppressed by more oil applications. Predatory mite populations were lower in both oil programs than in the check, but it is difficult to determine whether direct toxicity or reduction of prey was responsible for lower predator populations. There also was some evidence that oil suppressed woolly apple aphid, Eriosoma lanigerum Hausman. The six-spray oil program largely prevented a woolly apple aphid outbreak that occurred in July and August 1998 in the check, although the three-spray program seemed to provide some suppression despite the nonspecific spray timing.
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Control de Insectos/métodos , Malus/crecimiento & desarrollo , Aceite Mineral/administración & dosificación , Estaciones del Año , Animales , Áfidos , Larva/crecimiento & desarrollo , Ácaros , Mariposas Nocturnas , Densidad de PoblaciónRESUMEN
Three neonicotinyl insecticides, acetamiprid, thiacloprid and clothianidin, were evaluated for their impact on four species of lepidopteran pests of apple in Washington, the codling moth, Cydia pomonella (L.), the Pandemis leafroller, Pandemis pyrusana Kearfott, and the obliquebanded leafroller, Choristoneura rosaceana (Harris), and Lacanobia subjuncta (Grote & Robinson). None of the neonicotinyl insecticides demonstrated sufficient activity against P. pyrusana, C. rosaceana, or L. subjuncta to warrant field trials. Conversely, all had some activity against one or more stages of C. pomonella. Acetamiprid was highly toxic to larvae in laboratory bioassays, and had relatively long activity of field-aged residues (21 days). It also showed some toxicity to C. pomonella eggs (via topical exposure) and adults. Acetamiprid provided the highest level of fruit protection from C. pomonella attack in field trials conducted over five years in experimental orchards with extremely high codling moth pressure. Thiacloprid performed similarly in bioassays, but fruit protection in field trials was slightly lower than acetamiprid. Clothianidin showed moderate to high toxicity in bioassays, depending on the C. pomonella stage tested, but poor fruit protection from attack in field trials. None of the neonicotinyl insecticides were as toxic to larvae or effective in protecting fruit as the current standard organophosphate insecticide used for C. pomonella control, azinphosmethyl. However, both acetamiprid and thiacloprid should provide acceptable levels of C. pomonella control in commercial orchards where densities are much lower than in the experimental orchards used for our trials. The advantages and disadvantages of the neonicotinyl insecticides as replacements for the organophosphate insecticides and their role in a pest management system for Washington apple orchards are discussed.
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Insecticidas , Lepidópteros , Malus/parasitología , Agricultura/métodos , Animales , Azinfosmetilo , Bioensayo/métodos , Relación Dosis-Respuesta a Droga , Guanidinas , Control de Insectos/métodos , Larva/efectos de los fármacos , Dosificación Letal Mediana , Neonicotinoides , Óvulo/efectos de los fármacos , Piridinas , Tiazinas , Tiazoles , Factores de Tiempo , WashingtónRESUMEN
The effect of neonicotinyl insecticides on integrated mite control in Washington apple was examined from 0 In a series of 20 field trials (54 treatments) designed primarily to look at efficacy against the codling moth, Cydia pomonella, nearly half of the treatments using four or more applications of acetamiprid had peak mite densities exceeding the economic threshold of 5 mites per leaf. Overall, acetamiprid treatments had 4.6-fold higher mite densities than the standard organophosphate insecticide treatment. Of the treatments with high mite populations, Panonychus ulmi, the European red mite, and Tetranychus urticae, the twospotted spider mite, were the dominant species in roughly equal numbers of cases. Only 11.1% of the thiacloprid treatments exceeded 5 mites per leaf; these experimental treatments included eight applications, whereas the current label restricts the number of applications at the rate for C. pomonella to two applications. One out of six clothianidin treatments caused a significantly higher mite density than the standard treatment; however, this material appeared to suppress predatory mites. Neonicotinyl insecticides did not eliminate predatory mites, but they inhibited their ability to respond normally to increasing prey populations. In field trials designed specifically to examine mite population densities where neonicotinyl insecticides were used, significantly higher levels of tetranychid mites occurred in one or more acetamiprid treatments (one, two or four applications) in five out of six trials. In the sixth trial (in a commercial orchard), only two acetamiprid applications were made, and mite populations were low in all treatments. While elevated mite densities were more likely to occur with four applications, in one case it occurred following a single application. The predominant tetranychid mite species (either P. ulmi or T. urticae) varied from trial to trial; however, there was no apparent bias regarding stimulation of the two species. Horticultural mineral oil was used with acetamiprid in some trials in an attempt to mitigate mite outbreaks. However, the addition of oil did not counteract the tendency of acetamiprid to increase tetranychid mite populations, and in one trial, had a negative effect on predatory mite densities. Seasonal tetranychid mite density was positively related to the total grams AI (or number of applications) of acetamiprid, thus reducing the number of applications per season should lower the probability of mite outbreaks.
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Anabasina/análogos & derivados , Control de Insectos , Insecticidas , Lepidópteros , Malus , Animales , Bioensayo , Relación Dosis-Respuesta a Droga , Guanidinas , Larva , Dosificación Letal Mediana , Aceite Mineral , Neonicotinoides , Óvulo , Densidad de Población , Piridinas , Estaciones del Año , Tiazinas , Tiazoles , Factores de Tiempo , WashingtónRESUMEN
A simple semiquantitative microassay was developed for the measurement of relative number of infected peripheral blood mononuclear cells (PBMC) from individuals infected with human immunodeficiency virus (HIV). The assay is based on cocultivation of serially diluted PBMC of a seropositive person with phytohemagglutinin-stimulated normal PBMC. The microassay has comparable sensitivity with the standard virus culture method in detecting positive HIV cultures. Since the microassay uses only 2-3 x 10(5) patients' PBMC, the assay is also most suitable for HIV isolation from HIV-infected infants or from AIDS patients with extremely low T-cell counts. The microassay can also be used to measure antiviral effects of a drug on persistent HIV infection in vitro. Because the microassay measures the relative number of infected PBMC, it can be readily used for following the quantitative antiviral effect of a drug in a clinical trial.
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Infecciones por VIH/microbiología , VIH/aislamiento & purificación , Leucocitos Mononucleares/microbiología , Virología/métodos , Complejo Relacionado con el SIDA/sangre , Complejo Relacionado con el SIDA/microbiología , Síndrome de Inmunodeficiencia Adquirida/sangre , Síndrome de Inmunodeficiencia Adquirida/microbiología , Infecciones por VIH/sangre , Seropositividad para VIH/sangre , Seropositividad para VIH/microbiología , HumanosRESUMEN
The time-dependent Schrodinger equation is solved for a 1Dx1D two-electron model helium atom subject to a low-frequency short, intense laser pulse. A half-cycle pulse leads to strong single but no double ionization. A full-cycle pulse leads to double ionization which begins precisely at the classical return time for the first ejected electron. When the excursion range for the first electron is truncated, the double ionization at later times, corresponding to longer excursions, disappears. When the field near the nucleus is turned off during the return of the first electron, double ionization persists.
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Thresholds of non-painful and painful perception for electrical stimuli are not altered significantly during dorsal column stimulation either in the area of induced paresthesia or outside it. After long term stimulation of the dorsal column the thresholds for stimuli are significantly higher within the area of induced paresthesia but not outside it. Median nerve evoked somatosensory cortical potentials are not altered by conditioning or simultaneous DC stimulation. During DCS in three of eight patients only the vibration evoked cortical potentials were attenuated in the early three components of the potential.
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Estimulación Eléctrica , Dolor Intratable/terapia , Médula Espinal , Adulto , Electroencefalografía , Potenciales Evocados , Humanos , Masculino , Nervio Mediano , Persona de Mediana Edad , Dolor Intratable/psicología , Parestesia/psicología , Percepción , Corteza SomatosensorialRESUMEN
In 13 patients suffering form Huntington's chorea (H.Ch.), VEPs and SEPs were investigated in comparison to 9 clinically inconspicuous offspring and normal adults. 1. The mean amplitude of VEP was reduced in choreatic patients and in four out of nine offspring. 2. Latencies of P100 in VEP were normal in all subjects. 3. The late components were reduced in amplitude and rather irregular in shape. 4. The latencies of SEPs were slightly prolonged, less marked in the early peaks and more pronounced in the later ones. 5. The late components after 70 to 100 msec were often attenuated or even absent. 6. The mean amplitude of the first two peaks was reduced. 7. Interhemispheric asymmetries were pronounced in three out of nine offspring.
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Potenciales Evocados Somatosensoriales , Potenciales Evocados Visuales , Enfermedad de Huntington/fisiopatología , Corteza Somatosensorial/fisiopatología , Corteza Visual/fisiopatología , Adulto , Anciano , Femenino , Humanos , Enfermedad de Huntington/genética , Masculino , Persona de Mediana Edad , Estimulación Luminosa , Valores de Referencia , Visión Ocular , Percepción VisualRESUMEN
In 200 patients with suspected MS, the diagnostic value of VEP elicited by checkerboard reversal and central foveal stimulation was compared. No significant difference was evident, but both methods overlap. The more stable checkerboard reversal stimulation should be preferred as a diagnostic method. Only in suspected MS with normal checkerboard responses, additional foveal responses may give supplementary information. Normal VEPs cannot exclude a prior retrobulbar neuritis.
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Potenciales Evocados Visuales , Esclerosis Múltiple/diagnóstico , Diagnóstico Diferencial , Humanos , Esclerosis Múltiple/fisiopatología , Estimulación LuminosaRESUMEN
Adrenocorticotropic hormone (ACTH) secreting islet cell tumors of the pancreas are extremely rare. A case of an ACTH producing islet cell tumor with multiple liver metastases is reported and the magnetic resonance imaging (MRI) findings are described.
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Adenoma de Células de los Islotes Pancreáticos/diagnóstico , Hormona Adrenocorticotrópica/metabolismo , Medios de Contraste , Gadolinio , Hormonas Ectópicas/metabolismo , Imagen por Resonancia Magnética , Neoplasias Pancreáticas/diagnóstico , Adenoma de Células de los Islotes Pancreáticos/metabolismo , Adulto , Humanos , Masculino , Neoplasias Pancreáticas/metabolismoRESUMEN
In 15 sitting volunteers with eyes covered the vestibulo- and cervico-ocular reflexes were tested with sinusoidal movements around the vertical axis of the body, at frequencies of 0.05, 0.1 and 0.2 s-1 and a total amplitude of 40 degrees. When the trunk was moved against the fixed head, the subjects described mainly an illusionary head movement at 0.05 s-1, while, at 0.2 s-1 only the trunk movement was perceived. Subjects asked to imagine head motion during COR showed increased eye shifts and total saccadic amplitudes. With concentration on trunk movement perception these values decreased.
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Movimiento , Cuello/fisiología , Nistagmo Fisiológico , Reflejo/fisiología , Adulto , Femenino , Cabeza/fisiología , Humanos , Cinestesia/fisiología , Masculino , Percepción de MovimientoRESUMEN
Eye movements were measured in 15 volunteers during vestibulo-ocular reflex (VOR), cervico-ocular reflex with the head fixed from the ceiling (passive COR), during voluntary stabilization of the head in space while the trunk was moved sinusoidally (active COR) and active head movements with and without additional vestibular or cervical stimuli. The subjects were sitting with eyes covered on a rotating chair swinging sinusoidally at 40 degrees peak to peak amplitude at 0.05, 0.1 and 0.2 Hz. The saccadic activity during passive COR is below the VOR and increases slightly during active COR. During voluntary head movements it shows a marked increase and is further activated if cervical or vestibular stimuli are added. The amplitudes of eye shifts of passive and active COR are not different. During active head movements and more with additional cervical or vestibular input, they increase significantly. The phase of the maximum eye shifts to head position is anticompensatory during passive COR and compensatory during VOR. The phase lead of about 45 degrees during active head movements is less during active COR but is larger with additional cervical and vestibular stimuli reaching 90 degrees.
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Movimientos Oculares , Músculos/inervación , Músculos del Cuello/inervación , Núcleos Vestibulares/fisiología , Adulto , Femenino , Fijación Ocular , Humanos , Masculino , Nistagmo Fisiológico , Reflejo/fisiología , Nervio Vestibular/fisiologíaRESUMEN
In healthy subjects eye movements were analysed during body rotation, during trunk torsion either with the head passively held stationary in space or with the head voluntarily stabilized in space, and during voluntary head movements. Trapezoidal movements around the vertical axis were performed (+/- 40 degrees, plateau 10 s, duration of ramp 1 or 4 s). Moreover the influence of a tonic head deviation up to 40 degrees on optokinetic nystagmus and on vestibulo-ocular reflex during sinusoidal turning was examined. Eye movements were recorded by DC-electrooculography. Saccadic and slow components of eye movements and the shift of eye position during the plateau of the trapezoidal stimulus were analysed. For all modes of stimulation during the plateau no nystagmus occurred. At the end of the dynamic phase of the stimulus relatively frequent eye deviations--mostly in the direction of the head deviation--were observed, not only after turning the trunk with the head stabilized in space (cervical stimulation) but also after turning head and trunk together. The fact that such eye deviations are thus observed even in the absence of any tonic, especially cervical stimulus, supports the assumption that they cannot be attributed to a tonic stimulus but merely to an effect of the preceding phasic stimulus which outlasts them. Also amplitude and direction of eye shifts during the plateau do not depend on a tonic stimulus, but merely on the eye deviation reached at the end of the dynamic phase of stimulation. Optokinetic nystagmus and vestibulo-ocular reflex are not influenced by an additional tonic cervical stimulus.
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Movimientos Oculares/fisiología , Movimiento/fisiología , Reflejo Vestibuloocular/fisiología , Adulto , Electrooculografía , Femenino , Cabeza , Humanos , Masculino , Nistagmo Fisiológico/fisiología , Anomalía TorsionalRESUMEN
The attraction of the stink bug Euschistus conspersus Uhler to sources of the synthetic pheromone component methyl (2E,4Z)-decadienoate was investigated in a series of field experiments in native vegetation surrounding commercial apple orchards in Washington. In experiments with pheromone lures placed inside two different tube-type traps, stink bugs were attracted to the immediate area around traps in large numbers, but very few were caught in the traps. Pheromone lures attached directly to the host plant mullein, Verbascum thapsus L., demonstrated that these 'baited" plants attracted significantly more E. conspersus than unbaited plants. Spring (reproductive) and summer (reproductively diapausing) E. conspersus adults, both males and females, were attracted to pheromone-baited plants. There was no significant difference in the number of male or female E. conspersus attracted to pheromone-baited traps or plants in any of the experiments, further characterizing methyl (2E,4Z)-decadienoate as an aggregation, and not a sex pheromone. Stink bug aggregations formed within 24-48 h of lure placement on mullein plants and remained constant until the lure was removed after which aggregations declined over 3-4 d to the level of unbaited plants. The implications of these studies for E. conspersus monitoring and management are discussed.