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排序方式: 共有336条查询结果,搜索用时 31 毫秒
101.
This letter is concerned with the problem of selecting the best or most informative dimension for dimension reduction and feature extraction in high-dimensional data. The dimension of the data is reduced by principal component analysis; subsequent application of independent component analysis to the principal component scores determines the most nongaussian directions in the lower-dimensional space. A criterion for choosing the optimal dimension based on bias-adjusted skewness and kurtosis is proposed. This new dimension selector is applied to real data sets and compared to existing methods. Simulation studies for a range of densities show that the proposed method performs well and is more appropriate for nongaussian data than existing methods. 相似文献
102.
TH Inge C Carmeci LJ Ohara WB Berquist JL Cahill 《Canadian Metallurgical Quarterly》1998,33(11):1614-1617
BACKGROUND: Intraoperative manometry is useful in performing Nissen fundoplication (NF) in children. Long-term clinical outcome information after use of this method is lacking. METHODS: A retrospective review of the outcomes of 62 consecutive NFs using intraoperative manometry was performed. The follow-up period was 3.4 years. Approximately half of the patients were neurologically normal (NN) and half were neurologically impaired (NI). All patients with gastroesophageal reflux disease (GERD) did not respond to an adequate trial of medical treatment. RESULTS: The NF was tailored to result in a twofold increase in the lower esophageal sphincter pressure (LESP) and a 75% increase in the LES length (LESL). An accelerated growth rate in 40% of "failure to thrive" (FTT) patients was demonstrated. Eighty-four percent of caregivers reported improved quality of life after NF. There was a twofold reduction in the number of hospital admissions and a sixfold reduction in total inpatient days for both NI and NN children. The early and late mortality rate was 13%, and the complication rate was similar to other series reported in the literature, with more complications occurring in NI patients. There was a 2% incidence of wrap herniation. An improvement in long-term outcomes after NF was seen in 89% of NN children and over half of NI patients. CONCLUSIONS: Intraoperative manometry is useful in standardizing the tightness of the wrap in NF. There was a low incidence of complications, dysphagia, recurrent emesis, and GERD in this series. Long-term outcomes using this technique were deemed very good based on caregivers' responses. 相似文献
103.
Inge Skjælaaen Anozie Ebigbo Magne Espedal Rainer Helmig 《Computing and Visualization in Science》2010,13(6):265-273
In several oilfields, reservoir souring by generation of hydrogen sulfide (H2S) occurs in secondary recovery during which seawater is injected into originally sweet reservoirs. At the production site,
high concentrations of H2S can cause severe damage to both equipment and human personnel. Proper modeling of H2S concentration in produced fluids can be useful for decision-making during field development design. We present a model for
the transport of H2S in an oil- and water-saturated, water-wet porous medium. The different retardation mechanisms for the H2S are described. For the adsorption of H2S to rock, we include two distinct phases of adsorption. In addition, we introduce a functional relationship between adsorption
capacity and permeability. As H2S mixes with oil, fractions become immobile as part of the residual oil. 相似文献
104.
We investigate the expressiveness of backward jumps in a frame work of formalized sequential programming called program algebra and characterize established non-uniform complexity classes in terms of instruction sequences, backward jumps and auxiliary
registers. 相似文献
105.
Inge de Wreede Hermann Stegemann und Hans Heinz Heinert 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1982,174(5):366-373
Zusammenfassung Die Veränderung von Proteinen bei verschiedener Hitzebelastung wird am Beispiel der Brühwurst untersucht. Die hocherhitzten Proben lassen sich elektrophoretisch, außer mit Hilfe der Polyacrylamidgelisoelektrischen Focussierung, nicht auftrennen. Es kommt zu Spaltungen, die eine gesteigerte Wasserlöslichkeit der Proteine bedingen, aber auch zu Vernetzungsreaktionen, die eine verminderte SDS-Löslichkeit zur Folge haben. Die Ursachen werden diskutiert und der Einfluß auf Bestimmungsmethoden wird untersucht.
Die Arbeit ist Ted der Dissertation von I. de Wreede.Sonderdruckanfragen an: H. Stegemann (Adresse siehe oben) 相似文献
Proteins in Bruhwurst solubility and the electrophoretic evaluation
Summary The changes of proteins after heating were investigated. Prolonged heating caused diffused bands in the electrophoretic pattern, only PAGIF yielded bands. The cleavage of peptide bounds raised the solubility of the denatured proteins in water. On the other side the solubility in SDS-containing buffers at room temperature is decreased. The influence of analytical methods is discussed.
Die Arbeit ist Ted der Dissertation von I. de Wreede.Sonderdruckanfragen an: H. Stegemann (Adresse siehe oben) 相似文献
106.
Sander De Bruyne Loes van Schie Jonas Himpe Filip De Somer Inge Everaert Wim Derave Caroline Van den Broecke Manon Huizing Nezahat Bostan Marijn Speeckaert Nico Callewaert Elisabeth Van Aken Joris R. Delanghe 《International journal of molecular sciences》2021,22(8)
Cataracts are the major cause of blindness worldwide, largely resulting from aging and diabetes mellitus. Advanced glycation end products (AGEs) have been identified as major contributors in cataract formation because they alter lens protein structure and stability and induce covalent cross-linking, aggregation, and insolubilization of lens crystallins. We investigated the potential of the deglycating enzyme fructosamine-3-kinase (FN3K) in the disruption of AGEs in cataractous lenses. Macroscopic changes of equine lenses were evaluated after ex vivo intravitreal FN3K injection. The mechanical properties of an equine lens pair were evaluated after treatment with saline and FN3K. AGE-type autofluorescence (AF) was measured to assess the time-dependent effects of FN3K on glycolaldehyde-induced AGE-modified porcine lens fragments and to evaluate its actions on intact lenses after in vivo intravitreal FN3K injection of murine eyes. A potential immune response after injection was evaluated by analysis of IL-2, TNFα, and IFNγ using an ELISA kit. Dose- and time-dependent AF kinetics were analyzed on pooled human lens fragments. Furthermore, AF measurements and a time-lapse of macroscopic changes were performed on intact cataractous human eye lenses after incubation with an FN3K solution. At last, AF measurements were performed on cataractous human eyes after crossover topical treatment with either saline- or FN3K-containing drops. While the lenses of the equine FN3K-treated eyes appeared to be clear, the saline-treated lenses had a yellowish-brown color. Following FN3K treatment, color restoration could be observed within 30 min. The extension rate of the equine FN3K-treated lens was more than twice the extension rate of the saline-treated lens. FN3K treatment induced significant time-dependent decreases in AGE-related AF values in the AGE-modified porcine lens fragments. Furthermore, in vivo intravitreal FN3K injection of murine eyes significantly reduced AF values of the lenses. Treatment did not provoke a systemic immune response in mice. AF kinetics of FN3K-treated cataractous human lens suspensions revealed dose- and time-dependent decreases. Incubation of cataractous human eye lenses with FN3K resulted in a macroscopic lighter color of the cortex and a decrease in AF values. At last, crossover topical treatment of intact human eyes revealed a decrease in AF values during FN3K treatment, while showing no notable changes with saline. Our study suggests, for the first time, a potential additional role of FN3K as an alternative treatment for AGE-related cataracts. 相似文献
107.
The effect of iron fortification is generally assumed to be less than iron supplementation; however, the magnitude of difference
in effects is not known. The present study aims to compare the efficacy of these two strategies on anaemia and iron status.
After screening on low Hb, 425 anaemic children in six primary schools in Tam Nong district of Phu Tho province were included
in a randomized, placebo-controlled trial comparing two groups receiving iron fortified instant noodles or iron supplementation
for 6 months and a control group, with children in all groups having been dewormed. Blood samples were collected before and
after intervention for haemoglobin, serum ferritin (SF), serum transferrin receptor (TfR), C-reactive protein (CRP), and haemoglobinopathies
analysis. Regression analysis was used to assess the effect of iron fortification and iron supplementation on haemoglobin
concentration, SF, TfR, body iron, and anaemic status as outcome variables. The improvement of haemoglobin, SF, and body iron
level in the group receiving iron fortification was 42% (2.6 g/L versus 6.2 g/L), 20% (23.5 μg/L versus 117.3 μg/L), and 31.3%
(1.4 mg/kg versus 4.4 mg/kg) of that in the iron supplementation group. The prevalence of anaemia dropped to 15.1% in the
control group, with an additional reduction of anaemia of 8.5% in the iron supplementation group. The additional reduction
due to iron fortification was 5.4%, which amounts to well over 50% of the impact of supplementation. In conclusion, the efficacy
of iron fortification based on reduction of prevalence of anaemia, and on the change in haemoglobin level, is about half of
the maximum impact of supplementation in case of optimal compliance. Thus, in a population of anaemic children with mild iron
deficiency, iron fortification should be the preferred strategy to combat anaemia. 相似文献
108.
Paul Inge Dahl Reidar Haugsrud Hilde Lea Lein Tor Grande Truls Norby Mari-Ann Einarsrud 《Journal of the European Ceramic Society》2007,27(16):4461-4471
Powders of pure and 5% ytterbium substituted strontium cerate (SrCeO3/SrCe0.95Yb0.05O3−δ) were prepared by spray pyrolysis of nitrate salt solutions. The powders were single phase after calcination in nitrogen atmosphere at 1100 °C (SrCeO3) and 1200 °C (SrCe0.95Yb0.05O3−δ). Dense SrCeO3 and SrCe0.95Yb0.05O3−δ materials were obtained by sintering at 1350–1400 °C in air. Heat treatment at 850 and 1000 °C, respectively, was necessary prior to sintering to obtain high density. The dense materials had homogenous microstructures with grain size in the range 6–10 μm for SrCeO3 and 1–2 μm for SrCe0.95Yb0.05O3−δ. The electrical conductivity of SrCe0.95Yb0.05O3−δ was in good agreement with reported data, showing mixed ionic–electronic conduction. The ionic contribution was dominated by protons below 1000 °C and the proton conductivity reached a maximum of 0.005 S/cm above 900 °C. In oxidizing atmosphere the p-type electronic conduction was dominating above 700 °C, while the contribution from n-type electronic conduction only was significant above 1000 °C in reducing atmosphere. 相似文献
109.
Oxygen-limited autotrophic nitrification-denitrification (OLAND) in a rotating biological contactor treating high-salinity wastewater 总被引:13,自引:0,他引:13
A lab-scale rotating biological contactor (RBC) reactor operated under OLAND conditions was slowly adapted during 178 days to increasing salt concentrations going up to 30 g NaCl L(-1). The reactor performed well during this experimental period. However, the removal capacity of the reactor was lower under high-salinity conditions. A removal efficiency of 84% was achieved at a N loading rate of 725 mg N L(-1) d(-1) and a salt concentration of 30 g L(-1). The effect of salt shock loading and adaptation to 30 g NaCl L(-1) on the specific nitritation and anammox activity of the biomass was investigated in short-term batch experiments. A salt shock loading of 30 g L(-1) caused a 43% decrease in specific nitritation activity and 96% loss of specific anammox activity compared to reference biomass (not exposed to salt). The salt-adapted biomass (3-4 weeks) showed a specific nitritation activity that was 23% lower, and a specific anammox activity that was 58% lower, compared to the reference biomass. Overall, these results demonstrate that the OLAND process can have the potential to treat ammonium-rich brines after adaptation to high salinity. 相似文献
110.