Parameter Identification of Multispan Rigid Frames Using a Stiffness Separation Method.

Identifying the parameters of multispan rigid frames is challenging because of their complex structures and large computational workloads. This paper presents a stiffness separation method for the static response parameter identification of multispan rigid frames. The stiffness separation method segments the global stiffness matrix of the overall structure into the stiffness matrices of its substructures, which are to be computed, thereby reducing the computational workload and improving the efficiency of parameter identification. Loads can be applied individually to each separate substructure, thereby guaranteeing obvious local static responses. The veracity and efficacy of the proposed methodology are substantiated by applying it to three- and eight-span continuous rigid frame structures. The findings indicate that the proposed approach significantly enhances the efficiency of parameter identification for multispan rigid frames.

The PERCIVAL detector: first user experiments.

The PERCIVAL detector is a CMOS imager designed for the soft X-ray regime at photon sources. Although still in its final development phase, it has recently seen its first user experiments: ptychography at a free-electron laser, holographic imaging at a storage ring and preliminary tests on X-ray photon correlation spectroscopy. The detector performed remarkably well in terms of spatial resolution achievable in the sample plane, owing to its small pixel size, large active area and very large dynamic range; but also in terms of its frame rate, which is significantly faster than traditional CCDs. In particular, it is the combination of these features which makes PERCIVAL an attractive option for soft X-ray science.

[Perioperative factors affecting the length of hospital stay after cesarean section of pregnant women with heart disease].

Objective: To explore the related factors influencing the length of hospital stay(LOS) of pregnant women with heart disease (PWHD) after cesarean section. Methods: A total of 306 patients with PWHD who underwent cesarean section from January 2012 to March 2019 were collected. Among them, 203 patients had not undergone heart surgery (uncorrected group) and 103 patients who had undergone heart surgery (corrected group) during the same period. Demographic, perioperative and postoperative data were recorded. Predictors associated with postoperative LOS were determined using univariate and multivariate linear regression analysis models. Results: (1) The median LOS after cesarean section in the uncorrected group was 6 days (5-8 days). The results of univariate linear regression analysis showed that 38 parameters had significant impact on LOS (P<0.05). The results of multivariate linear regression analysis showed that 5 parameters were independent risk factors for prolonged LOS in the uncorrected group; among them, the median LOS in uncorrected group with hypertensive disorders of pregnancy was 3 days longer than that in patients with PWHD alone [7 days (5-8 days) vs 4 days (4-5 days), ß=0.195, P=0.001]; the median LOS in uncorrected group with high serum creatinine was 3 days longer than normal patients [7 days (5-13 days) vs 4 days (4-5 days), ß=0.145, P=0.015]; the LOS of patients who chose general anesthesia was 2 days longer than that of patients who chose spinal anesthesia [6 days (4-8 days) vs 4 days (4-5 days), ß=0.154, P=0.007]; the LOS of patients with postoperative pulmonary infection was 4 days longer than that of patients without pulmonary infection [8 days (5-15 days) vs 4 days (4-5 days), ß=0.269, P<0.01]; the LOS of patients who admitted to ICU after surgery was 2 days longer than that not admitted patients [6 days (5-8 days) vs 4 days (4-5 days), ß=0.268, P<0.01]. (2) The median LOS after cesarean section in corrected group was 4 days (4-5 days). The results of univariate linear regression analysis showed that 8 parameters had significant impact on the LOS (all P<0.05). The results of multivariate linear regression analysis showed that 2 parameters, which were American Society of Anesthesiologists (ASA) grade (ß=0.198, P=0.028) and intraoperative blood loss (ß=0.285, P=0.003), were the independent risk factors for prolonged LOS in corrected group. Conclusion: Preoperative with hypertensive disorders of pregnancy, preoperative creatinine increase, intraoperative general anesthesia, postoperative pulmonary infection, and postoperative admission to ICU are independent predictors of prolonged LOS in uncorrected patients with PWHD; ASA classification and intraoperative bleeding are independent predictor of prolonged postoperative LOS in patients with corrected PWHD.

Estimation of vehicle-induced bridge dynamic responses using fiber Bragg grating strain gages.

Strain gage sensors have been used to evaluate the local behavior of structures; however, there are limited studies for its application in bridge dynamic feature identification. In this study, fiber Bragg grating strain gages were installed on the lower chord members of a bridge, and dynamic features were identified successfully using strain gage readings when vehicles passed over the bridge. The results were also verified using a finite element model. The innovation presented in this article is the use of fiber Bragg grating strain gage readings to identify the dynamic features of a long-span, steel-girder bridge. To clarify the effect of truck dynamic load, the load spectrum of the truck is characterized. This article introduces a new method for identifying the dynamic parameters of bridges.

Anesthetic management for cesarean delivery in a patient with uncorrected pulmonary atresia, ventricular septal defect and major aortopulmonary collateral arteries.

Pulmonary atresia witha ventricular septal defect and major aortopulmonary collateral arteries is an extremely rare congenital disorder characterized by a high risk of maternal mortality. We present the case of a 24-year-old primigravid woman with uncorrected pulmonary atresia, ventricular septal defect and major aortopulmonary collateral arterieswho presented at 35+5 weeks' gestation. Based on the pathophysiology of the congenital cardiac lesion, cesarean delivery was performed under epidural anesthesia under management by a multidisciplinary team. This report highlights the anesthesia management of a rare uncorrected congenital cardiac lesion for cesarean delivery.

Monitoring Bridge Dynamic Responses Using Fiber Bragg Grating Tiltmeters.

In bridge health monitoring, tiltmeters have been used for measuring rotation and curvature; however, their application in dynamic parameter identification has been lacking. This study installed fiber Bragg grating (FBG) tiltmeters on the bearings of a bridge and monitored the dynamic rotational angle. The dynamic features, including natural frequencies and mode shapes, have been identified successfully. The innovation presented in this paper is the first-time use of FBG tiltmeter readings to identify the natural frequencies of a long-span steel girder bridge. The identified results have been verified using a bridge finite element model. This paper introduces a new method for the dynamic monitoring of a bridge using FBG tiltmeters. Limitations and future research directions are also discussed in the conclusion.

Serum catalytic Iron: A novel biomarker for coronary artery disease in patients on maintenance hemodialysis.

Cardiovascular disease is the leading cause of morbidity and mortality in maintenance hemodialysis (MHD) patients. We evaluated the role of serum catalytic iron (SCI) as a biomarker for coronary artery disease (CAD) in patients on MHD. SCI was measured in 59 stable MHD patients. All patients underwent coronary angiography. Significant CAD was defined as a > 70% narrowing in at least one epicardial coronary artery. Levels of SCI were compared with a group of healthy controls. Significant CAD was detected in 22 (37.3%) patients, with one vessel disease in 14 (63.63%) and multi-vessel disease in eight (36.36%) patients. The MHD patients had elevated levels of SCI (4.70 ± 1.79 µmol/L) compared with normal health survey participants (0.11 ± 0.01 µmol/L) (P < 0.0001). MHD patients who had no CAD had SCI levels of 1.36 ± 0.34 µmol/L compared with those having significant CAD (8.92 ± 4.12 µmol/L) (P < 0.0001). Patients on MHD and diabetes had stronger correlation between SCI and prevalence of CAD compared with non-diabetics. Patients having one vessel disease had SCI of 8.85 ± 4.67 µmol/L versus multi-vessel disease with SCI of 9.05 ± 8.34 µmol/L, P = 0.48. In multivariate analysis, SCI and diabetes mellitus were independently associated with significant CAD. We confirm the high prevalence of significant CAD in MHD patients. Elevated SCI levels are associated with presence of significant coronary disease in such patients. The association of SCI is higher in diabetic versus the non-diabetic subgroup. This is an important potentially modifiable biomarker of CAD in MHD patients.

Long-term belatacept exposure maintains efficacy and safety at 5 years: results from the long-term extension of the BENEFIT study.

The Belatacept Evaluation of Nephroprotection and Efficacy as First-line Immunosuppression Trial randomized patients receiving a living or standard criteria deceased donor kidney transplant to a more (MI) or less intensive (LI) regimen of belatacept or cyclosporine A (CsA). The 5-year results of the long-term extension (LTE) cohort are reported. A total of 456 (68.5% of intent-to-treat) patients entered the LTE at 36 months; 406 patients (89%) completed 60 months. Between Months 36 and 60, death occurred in 2%, 1% and 5% of belatacept MI, belatacept LI and CsA patients, respectively; graft loss occurred in 0% belatacept and 2% of CsA patients. Acute rejection between Months 36 and 60 was rare: zero belatacept MI, one belatacept LI and one CsA. Rates for infections and malignancies for Months 36-60 were generally similar across belatacept groups and CsA, respectively: fungal infections (14%, 15%, 12%), viral infections (21%, 18%, 16%) and malignancies (6%, 6%, 9%). No new posttransplant lymphoproliferative disorder cases occurred after 36 months. Mean calculated GFR (MDRD, mL/min/1.73 m(2) ) at Month 60 was 74 for belatacept MI, 76 for belatacept LI and 53 for CsA. These results show that the renal function benefit and safety profile observed in belatacept-treated patients in the early posttransplant period was sustained through 5 years.

Preparation of linoleic acid-capped silver nanoparticles and their antimicrobial effect.

Silver nanoparticles have been prepared through the chemical reduction of silver ions by ethanol using linoleic acid as a stabilising agent. This colloidal solution shows an absorption band in the visible range with an absorption peak at 421 nm. The peaks in the X-ray diffraction (XRD) pattern matches well with the standard values of the face-centred-cubic form of metallic silver. Transmission Electron Microscope (TEM) micrograph shows a nearly uniform distribution of the particles with an average size of 8 nm. This linoleic acid-capped silver nanoparticles show antimicrobial activity against Escherichia coli and Staphylococcus aureus.

Evaluation of CT coronary artery angiography with 320-row detector CT in a high-risk population.

OBJECTIVES: The aim of this article was to prospectively evaluate the accuracy and radiation dose of 320-detector row dynamic volume CT (DVCT) for the detection of coronary artery disease (CAD) in a high-risk population. METHODS: 60 patients with a high risk of CAD underwent DVCT without preceding heart rate control and also underwent invasive coronary angiography (ICA), which served as the standard reference. RESULTS: On a per segment analysis, overall sensitivity was 95.3%, specificity was 97.6%, positive predictive value was 90.6%, negative predictive value was 98.8% and Youden index was 0.93. In both heart rate subgroups, diagnostic accuracy for the assessment of coronary artery stenosis was similar. The accuracy of the subgroup with an Agatston score ≥100 was lower than that for patients with an Agatston score <100. However, the difference between DVCT and ICA results was not significant (p=0.08). The mean estimated effective dose of CT was 12.5 ± 9.4 mSv. In those patients with heart rates less than 70 beats per minute (bpm), the mean radiation exposure of DVCT was 5.2 ± 0.9 mSv. The effective radiation dose was significantly lower than that of ICA (14.1 ± 5.9 mSv) (p<0.001). When the heart rate was >70 bpm, a significantly higher dose was delivered to patients with DVCT (22.6 ± 5.2 mSv, p<0.001) than with ICA (15.0 ± 5.3 mSv, p<0.001). CONCLUSION: DVCT reliably provides high diagnostic accuracy without heart rate/rhythm control. However, from a dosimetric point of view, it is recommended that heart rate should be controlled to <70 bpm to decrease radiation dose.

Protective Role of Catechin on d-Galactosamine Induced Hepatotoxicity Through a p53 Dependent Pathway.

Objective of this study was to obtain a better understanding of the mechanism responsible for the d-galactosamine (d-GalN) induced hepatotoxicity and to study the effect of catechin against d-GalN induced hepatotoxicity. Catechin 50 and 100 mg/kg b.wt was administered for 1 week by oral route. Liver damage was induced by intra-peritoneal administration of 400 mg/kg b.wt d-galactosamine on the last day of catechin treatment. At the end of treatment all animals were killed and liver enzyme levels were estimated. Dissected hepatic samples were used for histopathology, RNA isolation, expression studies of Bax, Bcl-2 and p53 mRNA levels and mitochondrial membrane potential studies. We found that increases in the liver enzyme activity and decrease in antioxidant enzyme activity by d-GalN were significantly restricted by oral pretreatment with catechin. Disruption of mitochondrial membrane potential, up regulation of p53, Bax and down regulation of Bcl-2 mRNA levels in the liver of d-GalN intoxicated rats were effectively prevented by pretreatment with catechin.

Is carbon dioxide a safe and good alternative for diatrizoate meglumine as a contrast in digital subtraction angiography?

Contrast-induced nephropathy is well-known sequelae of iodinated contrast (diatrizoate meglumine). Carbon dioxide (CO(2)) can be used as an alternative contrast agent. The aim of this study was to compare the renal injury and the quality of images of aortogram using iodinated contrast versus CO(2) using digital subtraction angiography (DSA). This prospective randomized study was done in 29 healthy dogs using DSA aortogram. Dogs were randomly assigned to receive iodinated contrast or CO(2). 6-F pigtail catheter was introduced via femoral artery approach to perform aortogram under general anesthesia. Serum creatinine (S.Cr.) and urinary enzymes, namely: N-acetyl D-glucosaminidase (NAG), alanine aminopeptidase (AAP), and gamma glutamyl transferase (GGT), were measured before and 48 hours after aortogram. There was no change in S.Cr. in both the groups. Significantly more enzymuria was seen following iodinated contrast than CO(2). Enzymuria pre and postaortogram following the iodinated contrast was GGT: 14.9 +/- 5.92 vs. 26.2 +/- 15.1 (P = 0.001), NAG: 1.63 +/- 0.90 vs. 3.6 +/- 2.14 (P = 0.0001), and AAP: 1.51 +/- 0.75 vs. 3.38 2.41 (P = 0.001), and in the CO(2) group was GGT: 15.5 +/- 4.9 vs. 21.1 +/- 9.04 (P = 0.02), NAG: 2.12 +/- 1.06 vs. 3.82 3.27 (P = 0.08), and AAP: 1.28 +/- 0.76 vs. 2.51 +/- 1.72 (P = 0.03). More than 50% increase over the preprocedural value was significantly less following CO(2). Images obtained with iodinated contrast were superior to those with CO(2,) however, the quality of image with CO(2) was adequate for delineation of the renal artery and major branches. Both iodinated contrast and CO(2) cause significant enzymuria. More severe enzymuria (>50% increase) was seen significantly less with the use of CO(2). Quality of images is better with iodinated contrast.

Hypoglycaemic activity of Ocimum gratissimum in rats.

The hypoglycaemic effect of the methanolic extract of Ocimum gratissimum leaves was evaluated in normal and alloxan-induced diabetic rats. Intraperitoneal injection of the extract (400 mg/kg) significantly reduced plasma levels both in normal and diabetic rats by 56 and 68%, respectively.

[Analysis on the data regarding brucellosis at the National Monitoring Center].

Surveillance on brucellosis was carried out in 15 major monitoring places in 14 provinces from 1990 to 1996. The result indicated that in a few monitoring places the epidemic situation was stable but in many monitoring places outbreak had occurred in one or two monitoring places. Major source of infection was from infected sheep and cattle while in some old epidemic areas the pastoral area was active, which kept animals continuously excrete bacteria, making the potential of outbreak brucellosis exist. A tendency showed that the epidemic area was shifting to the farming and stockbreeding and agricultural areas. A comprehensive strategy including effective management and control the circulation of causative agent, needs to be developed.

Reappraisal of the inspiratory effect of Bötzinger complex on phrenic nerve discharge.

Experiments were done on 12 urethane-chloralose anaesthetized, vagotomized, paralysed and ventilated cats. The effects of electrical microstimulation at the augmenting expiratory neurons (Aug-e) of Bötzinger complex (Bot.c) were investigated. It was found that long train stimulation (100 Hz, 3-50 microA, 4-6 s) caused intensity-dependent inhibition of phrenic inspiratory discharge. The threshold for complete inhibition was 10 +/- 2 microA (mean +/- S.E.). The expiratory duration showed shortening at low intensity (< 7 microA) and prolongation at higher intensity. Short train stimulation (10 microA, 50 ms) delivered in inspiratory phase produced a two-part transient inhibition of phrenic discharge. The latencies of the first- and second-part inhibition were 4.7 +/- 0.16 ms and 95 +/- 3 ms, respectively. Complete termination of inspiration could be produced by a short train delivered at late inspiration. The results suggest the importance of the Aug-e neurons of Bot.c in determining inspiratory amplitude and respiratory phase duration.

Afferent projections to the Bötzinger complex from the upper cervical cord and other respiratory related structures in the brainstem in cats: retrograde WGA-HRP tracing.

Following injection of WGA-HRP (30-60 nl, 5%) into the Bötzinger complex (Böt.c), a group of expiratory neurons in the vicinity of the retrofacial nucleus, a number of labeled neurons were observed, predominantly ipsilaterally, in the intermediate zone of the upper cervical cord at the C1 and C2 segments, the retrotrapezoid nucleus (RTN) in the ventrolateral medulla and the parabrachial-Kölliker-Fuse nuclear complex in the rostral pons. In addition, clusters of labeled cells were also observed in and around the solitary tract nucleus, nuclei ambiguus and retroambiguus, and nucleus raphe magnus. Control injections into the magnocellular tegmental field adjacent to the Böt.c resulted in a diffuse distribution of labeled neurons in the reticular formation. These results demonstrate that the Böt.c receives convergent monosynaptic axonal projections from the upper cervical spinal cord, the pontine pneumotaxic area, the RTN and several other respiratory related structures in the medulla.