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101.
An experimental procedure is summarized to calculate automobile fuel consumption in the work trip and to indicate the implications of evaluating alternative subdivision street layouts. The results of the Residential Area Traffic Analysis Model show that annual fuel consumption increases with vehicle weight. The paper concludes that annual cost savings in fuel consumption and other benefits are realized by commuters who drive lighter cars. 相似文献
102.
Shaolie S. Hossain Yongjie Zhang Xiaoyi Fu Gerd Brunner Jaykrishna Singh Thomas J. R. Hughes Dipan Shah Paolo Decuzzi 《Journal of the Royal Society Interface》2015,12(106)
Peripheral arterial disease (PAD) is generally attributed to the progressive vascular accumulation of lipoproteins and circulating monocytes in the vessel walls leading to the formation of atherosclerotic plaques. This is known to be regulated by the local vascular geometry, haemodynamics and biophysical conditions. Here, an isogeometric analysis framework is proposed to analyse the blood flow and vascular deposition of circulating nanoparticles (NPs) into the superficial femoral artery (SFA) of a PAD patient. The local geometry of the blood vessel and the haemodynamic conditions are derived from magnetic resonance imaging (MRI), performed at baseline and at 24 months post intervention. A dramatic improvement in blood flow dynamics is observed post intervention. A 500% increase in peak flow rate is measured in vivo as a consequence of luminal enlargement. Furthermore, blood flow simulations reveal a 32% drop in the mean oscillatory shear index, indicating reduced disturbed flow post intervention. The same patient information (vascular geometry and blood flow) is used to predict in silico in a simulation of the vascular deposition of systemically injected nanomedicines. NPs, targeted to inflammatory vascular molecules including VCAM-1, E-selectin and ICAM-1, are predicted to preferentially accumulate near the stenosis in the baseline configuration, with VCAM-1 providing the highest accumulation (approx. 1.33 and 1.50 times higher concentration than that of ICAM-1 and E-selectin, respectively). Such selective deposition of NPs within the stenosis could be effectively used for the detection and treatment of plaques forming in the SFA. The presented MRI-based computational protocol can be used to analyse data from clinical trials to explore possible correlations between haemodynamics and disease progression in PAD patients, and potentially predict disease occurrence as well as the outcome of an intervention. 相似文献
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105.
Intestinal ultrasonography is a meanwhile established and valid diagnostic method in inflammatory bowel disease, diverticulitis, and appendicitis. Little, however, is known about other more rare intestinal diseases. Serving as a tertiary referral center for a broad spectrum of intestinal diseases we therefore report some aspects of ultrasonography in patients with acute and chronic enteritis and colitis of different origin, e.g., bacterial and viral colitis, ileocecal tuberculosis, AIDS-related enteritis, neutropenic colitis, cystic fibrosis, celiac sprue, vasculitis, benign and malignant tumors of the intestine, amyloidosis, ischemic colitis, and radiogenic enteritis. Ultrasonography may display the transformation of the intestinal wall from normal to pathological states both in inflammatory and neoplastic disease. Besides demonstrating the transmural aspect of inflammation it also shows the mesenteric reaction as well as complications such as fistula, abscesses, stenosis, or ileus. Furthermore, in some diseases intestinal ultrasonography may serve as a diagnostic clue if typical patterns of the bowel wall and impaired peristalsis can be demonstrated. This may lead to an important reduction of invasive and expensive procedures. Ultrasonography is of definite help in the follow-up of inflammatory changes of the bowel wall and primarily diagnostic with respect of other entities (e.g., penicillin-induced segmental hemorrhagic colitis). A sonographic differential diagnosis of diseases of the bowel wall on a purely morphological basis, however, is difficult and rather the exception than the rule. The information gained by ultrasonography regarding intestinal disease, however, is as important and valid as e.g., in case of focal lesions of the liver. 相似文献
106.
In the following we give an analysis of the local superconvergence properties of piecewise polynomial collocation methods and related continuous Runge-Kutta-type methods for Volterra integral equations with constant delay. We show in particular that (in contrast to delay differential equations) collocation at the Gauss points does not lead to higher-order convergence and thusm-stage Gauss-Runge-Kutta methods for delay Volterra equations do not possess the orderp=2m. 相似文献
107.
JW Martens M Verhoef-Post N Abelin M Ezabella SP Toledo HG Brunner AP Themmen 《Canadian Metallurgical Quarterly》1998,12(6):775-784
Leydig cell hypoplasia (LCH) is characterized by a decreased response of the Leydig cells to LH. As a result, patients with this syndrome display aberrant male development ranging from complete pseudohermaphroditism to males with micropenis but with otherwise normal sex characteristics. We have evaluated three brothers with a mild form of LCH. Analysis of their LH receptor (LHR) gene revealed a homozygous missense mutation resulting in a substitution of a lysine residue for a isoleucine residue at position 625 of the receptor. In vitro analysis of this mutant LHR, LHR(I625K), in HEK293 cells indicated that the signaling efficiency was significantly impaired, which explains the partial phenotype. We have compared this mutant LHR to two other mutant LHRs, LHR(A593P) and LHR(S616Y), identified in a complete and partial LCH patient, respectively. Although the ligand-binding affinity for all three mutant receptors was normal, the hormonal response of LHR(A593P) was completely absent and that of LHR(S616Y) and LHR(I625K) was severely impaired. Low cell surface expression explained the reduced response of LHR(S616Y), while for LHR(I625K) this diminished response was due to a combination of low cell surface expression and decreased coupling efficiency. For LHR(A593P), the absence of a reduced response resulted from both poor cell surface expression and a complete deficiency in coupling. Our experiments further show a clear correlation between the severity of the clinical phenotype of patients and overall receptor signal capacity, which is a combination of cell surface expression and coupling efficiency. 相似文献
108.
Results of fluorescence in situ hybridization (FISH) of Bos taurus and B. indicus Y chromosomes using the bovine locus-specific Y probes BC1.2 and lambda ES6.0 and region-specific probes of B. indicus and B. taurus Y chromosomes, which were generated by microdissection and DOP-PCR, indicate that the Y chromosomes of B. indicus (BIN Y) and B. taurus (BTA Y) differ by a pericentric inversion. Parts of the short and long arms of the Y chromosome in B. taurus and the distal half of the Y chromosome in B. indicus were microdissected, amplified by DOP-PCR, biotinylated, and rehybridized in situ to the corresponding metaphase chromosomes to test the chromosome fragment specificity of the DNA probes. The region-specific painting probes were used for hybridization to metaphase chromosomes of the other species. The DNA painting probes BTA Yp12 and BTA Yq12.1-ter derived from BTA Y hybridized to the distal and proximal halves of BIN Y, respectively. Complex hybridization signals on BTA Yq12.1-->qter were generated with the DNA probe BIN Yqcen-centr (centromere-central) after FISH. The results demonstrate that BTA Yp is homologous to the distal half of BIN Y and that BTA Yq corresponds to the proximal part of BIN Yq. Hybridization of the Y chromosome-specific DNA probes lambda ES6.0 to BTA Yp12-->p11 and near to the telomere of BIN Y and BC1.2 to BTA Yq12-->q13 and to the telomere of BIN Y indicate an opposite orientation of the homologous chromosome fragments BTA Yp and of the distal half of BIN Yq. 相似文献
109.
The performance of Napier et al.'s typist verification algorithm (Keyboard user verification: toward an accurate, efficient, and ecologically valid algorithm, International Journal of Human-Computer Studies 43 (1995) 213-222) was assessed in a text-dependent setting. Twenty-nine subjects typed a 17 character password 50 times. False acceptance and false rejection rates were then calculated as the number of repetitions of the password included in the reference profile was increased from 6 to 20 and the number of digraphs from the password included in the verification process was increased from 2 to 16. The performance of the system (12% total error rate) was found to be comparable with the best results reported in other studies using text-dependent algorithms, and substantially better than that reported in studies using a text-independent paradigm with passwords of this length. The relationship between password length and reference profile size was found to conform to an exponential decay function, which accounted for 92% of the variability in verification error rates. 相似文献
110.
U Klein W Karzai P Zimmermann U Hannemann U Koschel JX Brunner H Remde 《Canadian Metallurgical Quarterly》1998,24(12):1289-1293
We describe perinatal findings in a female fetus with partial trisomy 8q(8q24.1-->8qter) and partial monosomy 15q(15q26.1-->15qter) resulting from a paternal t(8;15) reciprocal translocation. Prenatal sonographic examination showed intra-uterine growth retardation, bilateral ventriculomegaly, cardiomegaly with arrhythmia, anhydramnios, and absent kidney and urinary bladder images. The pregnancy was terminated at 28 weeks of gestation. At birth, the infant manifested typical dysmorphic features of partial trisomy 8q. Necropsy further revealed hydrocephalus, congenital diaphragmatic hernia, ventricular septal defect, a horseshoe kidney with renal hypoplasia, and kyphoscoliosis. Our case shows that the coexistence of partial trisomy 8q24.1-->8qter and partial monosomy 15q26.1-->15qter are more detrimental than either defect alone and can result in a complex of major malformations. Prenatal ultrasound examination and cytogenetic assessment should be offered in subsequent pregnancies. 相似文献