946 resultados para time-of-use
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Objective: To investigate the follicular size at spontaneous rupture on pregnancy rate in patientswith polycystic ovary syndrome (PCOS) undergoing clomiphene citrate (CC) ovulation.Design: Cross-sectional study.Patients and methods: One hundred and four women with ovulatory cycles after use of CCfollowed by ultrasound to determine the follicle size at the time of rupture, which wassubsequently correlated with the occurrence of pregnancy or not in coit cycles.Results: In the group of follicular rupture at a mean diameter25 mm (n¼54), pregnancy ratewas 35.1% and when follicular rupture occurred at a mean diameter425 mm (n¼50), it was34% (p40.05). When different diameters at follicular rupture were randomly correlated with thepregnancy rate, there was no significant difference.Conclusion: Our data suggest that the occurrence of pregnancy after ovulation induction withCC in women with PCOS is not associated with follicle size at the time of rupture.
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The reaction of living anionic polymers with 2,2,5,5-tetramethyl-1-(3-bromopropyl)-1-aza-2,5- disilacyclopentane (1) was investigated using coupled thin layer chromatography and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Structures of byproducts as well as the major product were determined. The anionic initiator having a protected primary amine functional group, 2,2,5,5-tetramethyl- 1-(3-lithiopropyl)-1-aza-2,5-disilacyclopentane (2), was synthesized using all-glass high-vacuum techniques, which allows the long-term stability of this initiator to be maintained. The use of 2 in the preparation of well-defined aliphatic primary amine R-end-functionalized polystyrene and poly(methyl methacrylate) was investigated. Primary amino R-end-functionalized poly(methyl methacrylate) can be obtained near-quantitatively by reacting 2 with 1,1-diphenylethylene in tetrahydrofuran at room temperature prior to polymerizing methyl methacrylate at -78 °C. When 2 is used to initiate styrene at room temperature in benzene, an additive such as N,N,N',N'- tetramethylethylenediamine is necessary to activate the polymerization. However, although the resulting polymers have narrow molecular weight distributions and well-controlled molecular weights, our mass spectra data suggest that the yield of primary amine α-end-functionalized polystyrene from these syntheses is very low. The majority of the products are methyl α-end-functionalized polystyrene.
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Time-of-flight photoemission spectromicroscopy was used to measure and compare the two-photon photoemission (2PPE) spectra of Cu and Ag nanoparticles with linear dimensions ranging between 40 nm and several 100 nm, with those of the corresponding homogeneous surfaces. 2PPE was induced employing femtosecond laser radiation from a frequency-doubled Ti:sapphire laser in the spectral range between 375 nm and 425 nm with a pulse width of 200 fs and a repetition rate of 80 MHz. The use of a pulsed radiation source allowed us to use a high-resolution photoemission electron microscope as imaging time-of-flight spectrometer, and thus to obtain spectroscopic information about the laterally resolved electron signal. Ag nanoparticle films have been deposited on Si(111) by electron-beam evaporation, a technique leading to hemispherically-shaped Ag clusters. Isolated Cu nanoparticles have been generated by prolonged heating of a polycrystalline Cu sample. If compared to the spectra of the corresponding homogeneous surfaces, the Cu and Ag nanoparticle spectra are characterized by a strongly enhanced total 2PPE yield (enhancement factor up to 70), by a shift (about 0.1 eV) of the Fermi level onset towards lower final state energies, by a reduction of the work function (typically by 0.2 eV) and by a much steeper increase of the 2PPE yield towards lower final state energies. The shift of the Fermi level onset in the nanoparticle spectra has been explained by a positive unit charge (localized photohole) residing on the particle during the time-scale relevant for the 2PPE process (few femtoseconds). The total 2PPE yield enhancement and the different overall shape of the spectra have been explained by considering that the laser frequency was close to the localized surface plasmon resonance of the Cu and Ag nanoparticles. The synchronous oscillations induced by the laser in the metal electrons enhance the near-zone (NZ) field, defined as the linear superposition of the laser field and the field produced in the vicinity of the particles by the forced charge oscillations. From the present measurements it is clear that the NZ field behavior is responsible for the 2PPE enhancement and affects the 2PPE spatial and energy distribution and its dynamics. In particular, its strong spatial dependence allows indirect transitions through real intermediate states to take place in the metal clusters. Such transitions are forbidden by momentum conservation arguments and are thus experimentally much less probable on homogeneous surfaces. Further, we investigated specially tailored moon-shaped small metal nanostructures, whose NZ field was theoretically predicted, and compared the calculation with the laterally resolved 2PPE signal. We could show that the 2PPE signal gives a clear fingerprint of the theoretically predicted spatial dependence of the NZ field. This potential of our method is highly attractive in the novel field of plasmonics.
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Many research-based instruction strategies (RBISs) have been developed; their superior efficacy with respect to student learning has been demonstrated in many studies. Collecting and interpreting evidence about: 1) the extent to which electrical and computer engineering (ECE) faculty members are using RBISs in core, required engineering science courses, and 2) concerns that they express about using them, are important aspects of understanding how engineering education is evolving. The authors surveyed ECE faculty members, asking about their awareness and use of selected RBISs. The survey also asked what concerns ECE faculty members had about using RBISs. Respondent data showed that awareness of RBISs was very high, but estimates of use of RBISs, based on survey data, varied from 10% to 70%, depending on characteristics of the strategy. The most significant concern was the amount of class time that using an RBIS might take; efforts to increase use of RBISs must address this.
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OBJECTIVE To analyze the transit time from various locations in the intestines of cows with cecal dilatation-dislocation (CDD), healthy control cows, and cows with left displacement of the abomasum (LDA). ANIMALS 15 cows with naturally occurring CDD (group 1), 14 healthy control cows (group 2), and 18 cows with LDA (group 3). PROCEDURES 5 electronic transmitters were encased in capsules and placed in the lumen of the ileum, cecum, proximal portion of the colon, and 2 locations in the spiral colon (colon 1 and colon 2) and used to measure the transit time (ie, time between placement in the lumen and excretion of the capsules from the rectum). Excretion time of the capsules from each intestinal segment was compared among groups. RESULTS Cows recovered well from surgery, except for 1 cow with relapse of CDD 4 days after surgery and 2 cows with incisional infection. High variability in capsule excretion times was observed for all examined intestinal segments in all groups. Significant differences were detected for the excretion time from the colon (greater in cows with CDD than in healthy control cows) and cecum (less in cows with LDA than in cows of the other 2 groups). CONCLUSIONS AND CLINICAL RELEVANCE The technique developed to measure excretion time of capsules from bovine intestines was safe and reliable; however, the large variability observed for all intestinal segments and all groups would appear to be a limitation for its use in assessment of intestinal transit time of cattle in future studies.
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One of the broad objectives of the Nigerian health service, vigorously being pursued at all levels of government, is to make comprehensive health care available and accessible to the population at the lowest possible cost, within available resources. Some state governments in the federation have already introduced free medical service as a practical way to remove financial barriers to access and in turn to encourage greater utilization of publicly funded care facilities.^ To aid health planners and decision makers in identifying a shorter corridor through which urban dwellers can gain access to comprehensive health care, a health interview survey of the metropolitan Lagos was undertaken. The primary purpose was to ascertain the magnitude of access problems which urban households face in seeking care from existing public facilities at the time of need. Six categories of illness chosen from the 1975 edition of the International Classification of Disease were used as indicators of health need.^ Choice of treatment facilities in response to illness episode was examined in relation to distance, travel time, time of use and transportation experiences. These were graphically described. The overall picture indicated that distance and travel time coexist with transportation problems in preventing a significant segment of those in need of health care from benefitting in the free medical service offered in public health facilities. Within this milieu, traditional medicine and its practitioners became the most preferred alternative. Recommendations were offered for action with regard to decentralization of general practitioner (GP) consultations in general hospitals and integration of traditional medicine and its practitioners into public health service. ^
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El trabajo que aquí se presenta surge de la necesidad de conceptualizar y profundizar sobre el uso productivo del tiempo libre de las personas adultas mayores. Se llevará a cabo una aproximación teórica sobre las diferentes concepciones de tiempo libre y ocio como dimensiones interdisciplinarias que involucran elementos referidos al entorno en donde personas y comunidades buscan integrarse en un tiempo y espacio determinado
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El trabajo que aquí se presenta surge de la necesidad de conceptualizar y profundizar sobre el uso productivo del tiempo libre de las personas adultas mayores. Se llevará a cabo una aproximación teórica sobre las diferentes concepciones de tiempo libre y ocio como dimensiones interdisciplinarias que involucran elementos referidos al entorno en donde personas y comunidades buscan integrarse en un tiempo y espacio determinado
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El trabajo que aquí se presenta surge de la necesidad de conceptualizar y profundizar sobre el uso productivo del tiempo libre de las personas adultas mayores. Se llevará a cabo una aproximación teórica sobre las diferentes concepciones de tiempo libre y ocio como dimensiones interdisciplinarias que involucran elementos referidos al entorno en donde personas y comunidades buscan integrarse en un tiempo y espacio determinado
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Ocean Drilling Program Leg 169S retrieved a complete Holocene sequence from Saanich Inlet, British Columbia, Canada. Fish and diatom remains were extracted from sediments at Site 1034. Very small fish bones, teeth and scales were ubiquitous except in the lowermost glaciomarine clays; scales degraded with depth. In the identifiable fraction, Pacific herring were the most abundant with Pacific hake and cartilaginous fish yielding significant fractions. Fish remains appear just before 12 000 BP but greatest diversity does not occur until about 6500 BP. A smoothed abundance curve highlights two periods of maximal abundance at about 1500 and 6500 BP. Abundances in the last 1000 years are lower than the rest of the record. A correlation with abundances of seven phytoplankton taxa is significant; diatoms explain about a third of the variance. This study demonstrates the use of fish and diatoms from the same paleosedimentary matrix to examine millennia-scale correlations between primary and tertiary production.
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The stabilisation of pitch fibres (PFs) is the most important step for their subsequent use in the preparation of carbon fibres (CFs) and their resulting characteristics. The present work studies the influence that the stabilisation time has on the porosity of the CFs, and on the subsequent properties as carbon molecular sieve (CMS). The increase of the stabilisation time carried out at 573 K, from 2 to 8 h favours their CMS properties producing a decrease in the microposity accessible to N2, which gets completely blocked after 6 and 8 h, while the narrow microporosity (V-DR CO2) remains accessible. Adsorption kinetic studies with CH4 and CO2 were performed to assess the possibility of using these CFs as CMS by comparing them with Takeda 3A CMS. The results suggest that there is an optimal stabilisation time which allows the preparation of CFs from an abundant raw precursor with properties similar to Takeda 3A CMS.
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Real economic imbalances can lead to financial crisis. The current unsustainable use of our environment is such an imbalance. Financial shocks can be triggered by either intensified environmental policies, cleantech breakthroughs (both resulting in the stranding of unsustainable assets), or the economic costs of crossing ecological boundaries (eg floods and droughts due to climate change). Financial supervisors and risk managers have so far paid little attention to this ecological dimension, allowing systemic financial imbalances resulting from ecological pressures to build up. Inattention also leads to missed economic and financial opportunities from the sustainability transition.
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Mode of access: Internet.
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Mode of access: Internet.
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Published also, 1912, as v. 2 of the Publications of the Lincoln record society.