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11.
1. To study the relative contributions of luminal nutrition, bile and pancreatic secretions and hormonal factors in intestinal adaptation, lactation hyperphagia was chosen as a model for increased luminal nutrition, either alone (intestinal transection control group) or in combination with (i) exclusion of bile and pancreatic secretions from the jejunum (by transposition of the jejunum above the Ampulla of Vater) or (ii) exclusion of bile, pancreatic secretions and exogenous luminal nutrition from the jejunum (proximal Thiry-Vella by-pass group). 2. The results confirm that in lactation there is mucosal hyperplasia with increases in villus height and crypt depth, and in small-bowel wet and defatted dry-tissue weights per unit length of intestine. 3. There are corresponding changes in absorptive function with increased glucose and water absorption per unit length of intestine. 4. These structural and functional adaptive changes are proportionately greater in ileum than in jejunum. 5. The exclusion of exogenous luminal nutrition, bile and pancreatic secretions from the jejunum did not diminish the degree of intestinal mucosal hyperplasia and functional adaptation seen in lactation. 6. Diversion to the ileum of greater than normal amounts of bile, pancreatic secretions and luminal nutrition did not further increase the degree of mucosal hyperplasia and enhanced absorption seen in the lactating intestinal transection control group. 7. Unlike other models of intestinal adaptation, the changes in small-bowel mucosal structure and function seen in lactation are probably due to hormonal factors. 相似文献
12.
Upper and lower bounds to probability of error in binary communication systems with intersymbol interference are presented. Closed-form formulas are given for systems with filters having a finite number of lumped elements. Explicit results are given when the filters are Butterworth filters of orderN = 1, 2,..., 10 . Four systems are considered: with a sample detector (SD), with an integrate-integrated-and-dump detector (IDD), with a filter in receiver only, and with filters in receiver and transmitter. The transmitted signal is assumed to be of the nonreturn-nonreturn-to-zero (NRZ) form. 相似文献
13.
Formulas are derived for the error probability of M -ary frequency shift keying (FSK) with differential phase detection in a satellite mobile channel. The received signal in this channel is composed of a specular signal, a diffuse signal, and white Gaussian noise; hence, the composite signal is fading and has a Rician envelope. The error probability is shown to depend on the following system parameters: (1) the signal-to-noise ratio; (2) the ratio of powers in the specular and diffuse signal components; (3) the normalized frequency deviation; (4) the normalized Doppler frequency; (5) the maximum normalized Doppler frequency; (6) the correlation function of the diffuse component, which depends on the normalized Doppler frequency and the type of the antenna; (7) the number of symbols; and (8) the normalized time delay between the specular and diffuse component (t d/T ) where 1/T is the symbol rate. Except for T d/T , all normalized parameters are the ratios of the parameter value and symbol rate. The Doppler frequency depends on the velocity of the vehicle and the carrier frequency. The error probability is computed as a function of the various parameters. The bit error probability is plotted as a function of signal-to-noise ratio per bit and other system parameters 相似文献
14.
übersicht Es wird vorgeschlagen, den Reglerentwurf für nichtlineare Strecken auf die Synthese an Linearen parameterver?nderlichen Systemen (LPV-Systemen) zurückzuführen. Dies ist dann m?glich, wenn es gelingt ein nichtlineares Streckenmodell so umzuformen, da?
es als LPV-System betrachtet werden kann. Diese Umformung geschieht hier mit Hilfe einer nichtlinearen Zustandstransformation.
Als LPV-Entwurfsverfahren wird die Self-scheduled H
∞
-Regelung herangezogen. Die Demonstration der Strategie erfolgt an einem Beispiel.
Eingegangen: 9. Juli 1999 相似文献
Contents We present a new approach to reduce the controller design for general nonlinear plants to Linear parameter-varying systems (LPV-systems). Therefore we model a class of nonlinear systems as LPV system via a nonlinear state-transformation. This practise allows us to use LPV-controller design methods. In this article we apply Self-scheduled H ∞ -control. The proposed conception will be demonstrated on an example.
Eingegangen: 9. Juli 1999 相似文献
15.
Beerenwinkel N. Lengauer T. Selbig J. Schmidt B. Walter H. Korn K. Kaiser R. Hoffmann D. 《Intelligent Systems, IEEE》2001,16(6):35-41
This intelligent system uses information encoded in the HIV genomic sequence to predict the virus's resistance or susceptibility to drugs. To make predictions, geno2pheno employs decision tree classifiers and support vector machines. 相似文献
16.
Optimal control of option portfolios and applications 总被引:1,自引:0,他引:1
17.
Elane S Boa Morte Leticia M Costa Joaquim A Nobrega Maria das Gracas A Korn 《Food Additives & Contaminants》2008,25(5):616-621
The concentrations of major (Ca, K, Mg, Na and P) and trace elements (Al, Cu and Fe) in soy protein formulations sold in Bahia (Brazil) were determined by inductively coupled plasma-optical emission spectrometry (ICP-OES). Liquid and powdered soy protein formulation samples, both whole and light, were digested using a conventional heating program on a hot-plate. The powdered samples were prepared according to the label instructions for human consumption. A 5.0-ml aliquot of the soy protein emulsion was transferred to a borosilicate Erlenmeyer and concentrated nitric and sulfuric acid added. After a digestion time of approximately 50 min, hydrogen peroxide was added and heating continued to give a final volume of approximately 5 ml; the colorless digests were then made up to 15.0 ml with deionised water. Residual acid content was determined by acid-base titration. Good agreement between measured and certified values for all analytes in a non-fat milk powder (NIST SRM 1549) indicated that the method was suitable for major and trace elements determination in soy protein formulations. 相似文献
18.
Developed an intimacy interview and a rating system that allowed the reliable classification of 40 25–35 yr old women in 6 intimacy statuses. The interview/rating system included 2 new statuses: committed and uncommitted merger. The intimacy status interview and rating system, the Objective Measure of Ego-Identity Status (OMEIS), and 3 subscales from the Personality Research Form (PRF) were administered to Ss. It was predicted that merger Ss would score lower than Ss in other statuses on the Autonomy and Dominance and higher on the Succorance scales of the PRF. Results show that intimacy status was related to OMEIS scores. Most (7 of 9) committed merger Ss scored as identity diffuse or foreclosed. Nine uncommitted merger Ss scored as identity diffuse or moratorium. Ss in the moratorium category had strong religious involvement. Merger Ss had significantly higher scores on the Succorance scale of the PRF. Results are discussed in the context of childhood processes of attachment and separation. (11 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
19.
Matthias C. Schulz Paula Korn Bernd Stadlinger Ursula Range Stephanie Möller Jana Becher Matthias Schnabelrauch Ronald Mai Dieter Scharnweber Uwe Eckelt Vera Hintze 《Journal of materials science. Materials in medicine》2014,25(1):247-258
Dental implants are an established therapy for oral rehabilitation. High success rates are achieved in healthy bone, however, these rates decrease in compromised host bone. Coating of dental implants with components of the extracellular matrix is a promising approach to enhance osseointegration in compromised peri-implant bone. Dental titanium implants were coated with an artificial extracellular matrix (aECM) consisting of collagen type I and either one of two regioselectively low sulfated hyaluronan (sHA) derivatives (coll/sHA1Δ6s and coll/sHA1) and compared to commercial pure titanium implants (control). After extraction of the premolar teeth, 36 implants were inserted into the maxilla of 6 miniature pigs (6 implants per maxilla). The healing periods were 4 and 8 weeks, respectively. After animal sacrifice, the samples were evaluated histomorphologically and histomorphometrically. All surface states led to a sufficient implant osseointegration after 4 and 8 weeks. Inflammatory or foreign body reactions could not be observed. After 4 weeks of healing, implants coated with coll/sHA1Δ6s showed the highest bone implant contact (BIC; coll/sHA1Δ6s: 45.4 %; coll/sHA1: 42.2 %; control: 42.3 %). After 8 weeks, a decrease of BIC could be observed for coll/sHA1Δ6s and controls (coll/sHA1Δ6s: 37.3 %; control: 31.7 %). For implants coated with coll/sHA1, the bone implant contact increased (coll/sHA1: 50.8 %). Statistically significant differences could not be observed. Within the limits of the current study, aECM coatings containing low sHA increase peri-implant bone formation around dental implants in maxillary bone compared to controls in the early healing period. 相似文献
20.
S.V. Bulanov T.Zh. EsirkepovY. Hayashi M. KandoH. Kiriyama J.K. KogaK. Kondo H. KotakiA.S. Pirozhkov S.S. BulanovA.G. Zhidkov P. ChenD. Neely Y. KatoN.B. Narozhny G. Korn 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,660(1):31-42
We propose the experiments on the collision of laser light and high intensity electromagnetic pulses generated by relativistic flying mirrors, with electron bunches produced by a conventional accelerator and with laser wake field accelerated electrons for studying extreme field limits in the nonlinear interaction of electromagnetic waves. The regimes of dominant radiation reaction, which completely changes the electromagnetic wave-matter interaction, will be revealed in the laser plasma experiments. This will result in a new powerful source of ultra short high brightness gamma-ray pulses. A possibility of the demonstration of the electron-positron pair creation in vacuum in a multi-photon processes can be realized. This will allow modeling under terrestrial laboratory conditions neutron star magnetospheres, cosmological gamma ray bursts and the Leptonic Era of the Universe. 相似文献