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991.
The distribution of the protein energy ratio indicators (Pe%), amino acid score and protein value (NDpCal%) in the three daily meals (breakfast, lunch and dinner) of the diet of pregnant women from Santa María Cauqué, Guatemala, was studied. The results were compared with those obtained for the total daily food intake. The differences observed were not significant, confirming the validity of the determination of amino acid score, Pe% and NDpCal% in the foods consumed during the whole day in this type of populations. It also reflects the nutritional benefit of the food pattern, since protein utilization would not be decreased by a different distribution of protein quality and concentration throughout the three daily meals. The variability among individuals of Pe% intake, amino acid score and NDpCal% gave the following values: 16.0, 9.3 and 15.6, respectively. It is noteworthy to add that the variability of Pe% observed is similar to that reported for populations of developed countries. 相似文献
992.
The objective of this study was to determine whether progesterone prevents the stimulatory effects of oestradiol on GnRH receptor gene expression. In Expt 1, ewes were treated during the luteal phase (days 10-12 of the oestrous cycle) with either one or five subcutaneous implants containing oestradiol (n = 6 per group). Control ewes received no treatment (n = 6). Anterior pituitary glands were collected 16 h after treatment with oestradiol. Steady-state amounts of GnRH receptor mRNA were similar among all three treatment groups despite increased circulating concentrations of oestradiol in implanted ewes at the time of pituitary collection (4.3 +/- 0.6 and 24.7 +/- 2.6 pg ml-1 in ewes treated with one or five implants, respectively, compared with 0.5 pg ml-1 in controls). Experiment 2 was designed to determine whether progesterone was the ovarian factor preventing the stimulatory effects of oestradiol on expression of the GnRH receptor gene in Expt 1. Twenty-five ewes were ovariectomized on day 6 or day 7 of the oestrous cycle and assigned to one of five treatment groups (n = 5 per group). Control ewes received no further treatment. Endogenous luteal phase concentrations of progesterone were replaced in three groups of ewes at the time of ovariectomy via intravaginal implants. Three days after ovariectomy, one group of progesterone-treated ewes received one oestradiol implant, while another group of progesterone-treated ewes received five oestradiol implants. An additional group was treated with five oestradiol implants only, and anterior pituitary glands were collected from all ewes 16 h later. Compared with untreated ovariectomized ewes, treatment with progesterone alone did not affect amounts of GnRH receptor mRNA. In ewes treated with progesterone and either one or five oestradiol implants, steady-state amounts of GnRH receptor mRNA were increased twofold (P < 0.01). Treatment with oestradiol in the absence of progesterone increased amounts of GnRH receptor mRNA threefold (P < 0.001). These results provide evidence that the stimulatory effects of oestradiol on the expression of the GnRH receptor gene are prevented during the natural luteal phase in ewes. However, progesterone does not appear to act independently to mediate this effect. 相似文献
993.
In Spain, the study of socioeconomic differences in mortality has been limited by the fact that death certificates often do not include complete information on occupation. In this study, we chose those geographic areas with the highest quality information on occupation of the deceased in order to study socioeconomic differences in mortality from various causes of death. We used information from the death certificates of males who died between 30 and 64 years of age in eight Spanish provinces to compare mortality from the leading causes of death in professionals and managers (group I) and in manual laborers (group II) in 1980-82 and 1988-90. In each period the standardized mortality ratios (SMRs) were higher in group II, except for ischaemic heart disease during the first period, and cancer of the colon and rectum in both, although in the latter case the differences were not statistically significant. The ratio between the SMR from all causes in group II and group I was 1.27 in 1980-82, and 1.72 in 1988-90; for cancer of the colon and rectum the ratio went from 0.98 to 0.84, and for ischaemic heart disease, from 0.80 to 1.31. Except for cancer of the colon and rectum, which resulted in higher mortality in occupational group I, the excess mortality in occupational group II increased between the first and second period. The relation between socioeconomic level and mortality for ischaemic heart disease was reversed, a phenomenon similar to that which took place in the 1960s and 1970s in the developed countries.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
994.
Lower bounds on lengths of checking sequences 总被引:1,自引:0,他引:1
Guy-Vincent Jourdan Hasan Ural Hüsnü Yenigün Ji Chao Zhang 《Formal Aspects of Computing》2010,22(6):667-679
Lower bounds on the lengths of checking sequences constructed for testing from Finite State Machine-based specifications are
established. These bounds consider the case where a distinguishing sequence is used in forming state recognition and transition
verification subsequences and identify the effects of overlapping among such subsequences. Empirical results show that the
existing methods for construction of checking sequences provide checking sequences with lengths that are within acceptable
distance to these lower bounds. 相似文献
995.
996.
Lithium Intercalation Compound Dramatically Influences the Electrochemical Properties of Exfoliated MoS2 下载免费PDF全文
Adriano Ambrosi Zdeněk Sofer Martin Pumera 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(5):605-612
MoS2 and other transition metal dichalcogenides (TMDs) have recently gained a renewed interest due to the interesting electronic, catalytic, and mechanical properties which they possess when down‐sized to single or few layer sheets. Exfoliation of the bulk multilayer structure can be achieved by a preliminary chemical Li intercalation followed by the exfoliation due to the reaction of Li with water. Organolithium compounds are generally adopted for the Li intercalation with n‐butyllithium (n‐Bu‐Li) being the most common. Here, the use of three different organolithium compounds are investigated and compared, i.e., methyllithium (Me‐Li), n‐butyllithium (n‐Bu‐Li) and tert‐butyllithium (t‐Bu‐Li), used for the exfoliation of bulk MoS2. Scanning transmission electron microscopy (STEM), Raman spectroscopy, X‐ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV) are adopted for a comprehensive characterization of all materials under investigation. In addition, catalytic properties towards the hydrogen evolution reaction (HER) and capacitive properties are also tested. Different organolithium compounds exhibit different extent of Li intercalation resulting in different degrees of exfoliation. The inherent electrochemical behavior of MoS2 consisting of significant anodic and cathodic peaks as well as its capacitive behavior and catalytic properties towards hydrogen evolution reaction are strongly connected to the exfoliation compound used. This research significantly contributes to the development of large‐scale synthesis of electrocatalytic MoS2‐based materials. 相似文献
997.
R. A. Stern A. Rausch S. Deiker D. Martínez-Galarce L. Shing K. D. Irwin J. N. Ullom G. O’Neil G. Hilton L. Vale 《Journal of Low Temperature Physics》2008,151(3-4):721-726
LMSAL and NIST are developing position-sensitive X-ray strip detectors based on TES microcalorimeter arrays for solar physics.
An important application of these devices will be the study of high temperature (>10 MK) X-ray lines, e.g. Fe XXV, at high
spectral (E/ΔE≥1000) and temporal (sub-ms) resolution. Diagnostics from these lines will provide significant new insights into the physics
of microflares and the early stages of flares. In this paper, we will describe the current status of our laboratory test program
and applicability of our research to future space missions
相似文献
998.
The differential equation
is analysed, with n denoting the relaxing quantity, n = dn/dt(tis time), and a, band sconstants. Equations of this type have previously been shown to describe a large variety of relaxational patterns. Especially interesting is the close relationship with Bose–Einstein (B–E) like distributions and the underlying induction mechanisms. Here, the focus is on the special case of a= 0 which yields a generalised stretched exponential and, for certain variable ranges, the Kohlrausch (KWW) function in its usual form. The relaxation time is shown to depend strongly on the parameters entering the underlying differential equation. Conditions for constant are given. 相似文献
999.
Beatriz Maria Curtio Soares Carlos Alberto Rodrigues Anjos Taiane Bonfante Faria Sílvia Tondella Dantas 《Packaging Technology and Science》2016,29(1):65-73
The objectives of this study were to evaluate the characteristics of commercial soft drinks related with the corrosion process of the aluminium packaging and based on that, propose model solutions for future studies of beverage/package interaction and corrosion process of metal packages. Therefore, the pH, acidity, concentration of chlorides and copper in six types of soft drinks were determined, as well as the corrosion potential of the aluminium and the current density corrosion obtained in polarization curves using the beverages as electrolyte. Based on the results obtained, a solution of citric acid (pH = 3) containing chloride (250 mg/kg) and copper ions (250 µg/kg) is proposed. The obtained results are potentially useful for the industry and future studies regarding the interaction process between soft drinks and aluminium cans. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
1000.
Josef Jirák Ladislav Koudelka Jaroslav Pospíšil Petr Mošner Lionel Montagne Laurent Delevoye 《Journal of Materials Science》2007,42(20):8592-8598
Glasses of the ternary system ZnO–Bi2O3–P2O5 were prepared and studied in two compositional series 50ZnO–xBi2O3–(50 − x)P2O5 and (50 − y)ZnO–yBi2O3–50P2O5. Two distinct glass-forming regions were found in the 50ZnO–xBi2O3–(50 − x)P2O5 glass series with x = 0–10 and 20–35 mol.% Bi2O3. All prepared Bi2O3-containing glasses reveal a high chemical durability. Small additions of Bi2O3 (∼5 mol.%) improve thermal stability of glasses. All glasses crystallize on heating within the temperature range of 505–583 °C.
Structural studies by Raman and 31P MAS NMR spectroscopies showed the rapid depolymerisation of phosphate chains within the first region with x = 0–15 and the presence of isolated Q0 phosphate units within the second region with x = 20–35. Raman studies showed that bismuth is incorporated in the glass structure in BiO6 units and their vibrational bands were observed within the spectral region of 350–700 cm−1. The evolution of properties and the spectroscopic data are both in accordance with a network former effect of Bi2O3. 相似文献