Operator-based nonlinear feedback control design using robust right coprime factorization

In this note, robust stabilization and tracking performance of operator based nonlinear feedback control systems are studied by using robust right coprime factorization. Specifically, a new condition of robust right coprime factorization of nonlinear systems with unknown bounded perturbations is derived. Using the new condition, a broader class of nonlinear plants can be controlled robustly. When the spaces of the nonlinear plant output and the reference input are different, a space change filter is designed, and in this case this note considers tracking controller design using the exponential iteration theorem

Tracking of perturbed nonlinear plants using robust right coprime factorization approach

This paper deals with a plant output tracking design problem of perturbed nonlinear plants by using a robust right coprime factorization approach. An interesting control system design scheme, which was given by G. Chen and Z. Han, uses robustness of the right coprime factorization for robust stability of the closed-loop system with perturbation. Unfortunately, robust right coprime factorization cannot easily improve tracking performance of the control system except for simple cases. In this paper, a nonlinear operator-based design method for nonlinear plant output to track a reference input is given. Examples are presented to support the theoretical analysis.</p

On-line actuator state monitoring of a MIMO bioprocess

In the actuator state monitoring of a time varying human multi-joint arm dynamics, typical issues are compounded by problems related to the uncertainty factor consisting of measurement noises and modeling error of the rigid body dynamics. In general, the uncertainty factor is under the case of non-Gaussian noises. In this paper, for improving the monitoring, a robust filter system based on a score function approach is modified. The score function is associated with U_D factorization algorithm. The selection of the shape parameter in the monitoring filter is discussed. Examples of the proposed method for an experiment-based human arm model show better accuracy and robustness compared with standard Kalman filter.</p

Long-term effect of cinacalcet hydrochloride on abdominal aortic calcification in patients on hemodialysis with secondary hyperparathyroidism

Background: Secondary hyperparathyroidism (SHPT) is one of the common complications in dialysis patients, and is associated with increased risk of vascular calcification. The effects of cinacalcet hydrochloride treatment on bone and mineral metabolism have been previously reported, but the benefit of cinacalcet on vascular calcification remains uncertain. The aim of this study was to evaluate the impact of cinacalcet on abdominal aortic calcification in dialysis patients. Subjects and methods: Patients were on maintenance hemodialysis with insufficiently controlled SHPT (intact parathyroid hormone [PTH] >180 pg/mL) by conventional therapies. All subjects were initially administered 25 mg cinacalcet daily, with concomitant use of calcitriol analogs. Abdominal aortic calcification was annually evaluated by calculating aortic calcification area index (ACAI) using multidetector computed tomography (MDCT), from 12 months before to 36 months after the initiation of cinacalcet therapy. Results: Twenty-three patients were analyzed in this study. The mean age was 59.0±8.7 years, 34.8% were women, and the mean dialysis duration was 163.0±76.0 months. After administration of cinacalcet, serum levels of intact PTH, phosphorus, and calcium significantly decreased, and mean Ca × P values significantly decreased from 67.4±7.9 mg2/dL2 to 52±7.7 mg2/dL2. Although the ACAI value did not decrease during the observation period, the increase in ACAI between 24 months and 36 months after cinacalcet administration was significantly suppressed. Conclusion: Long-term administration of cinacalcet was associated with reduced progression of abdominal aortic calcification, and achieving appropriate calcium and phosphorus levels may reduce the rates of cardiovascular events and mortality in patients on hemodialysis

Signal Transduction Involving the Dmp1 Transcription Factor and its Alteration in Human Cancer

Dmp1 (cyclin D-interacting myb-like protein 1; also called Dmtf1) is a transcription factor that has been isolated in a yeast two-hybrid screen through its binding property to cyclin D2. Dmp1 directly binds to and activates the Arf promoter and induces Arf-p53-dependent cell cycle arrest in primary cells. D-type cyclins usually inhibit Dmp1-mediated transcription in a Cdk-independent fashion; however, Dmp1 shows synergistic effects with D-cyclins on the Arf promoter. Ras or Myc oncogene-induced tumor formation is accelerated in both Dmp1+/− and Dmp1−/− mice with no significant differences between Dmp1+/− and Dmp1−/−. Thus, Dmp1 is haplo-insufficient for tumor suppression. Tumors from Dmp1−/− or Dmp1+/− mice often retain wild-type Arf and p53, suggesting that Dmp1 is a physiological regulator of the Arf-p53 pathway. The Dmp1 promoter is activated by oncogenic Ras-Raf signaling, while it is repressed by physiological mitogenic stimuli, overexpression of E2F proteins, and genotoxic stimuli mediated by NF-κB. The human DMP1 gene (hDMP1) is located on chromosome 7q21 and is hemizygously deleted in approximately 40% of human lung cancers, especially those that retain normal INK4a/ARF and P53 loci. Thus, hDMP1 is clearly involved in human carcinogenesis, and tumors with hDMP1 deletion may constitute a discrete disease entity

Measurement of the muscle power of the toes in female marathon runners using a toe dynamometer.

The aim of this study was to investigate the relationship between the strength of the foot muscles that control the toes and disorders such as shin splint. In order to this, we designed and built a toe dynamometer to compare the muscle power exerted through the toes in top female marathon runners and age-matched women not involved in sports. The subjects were 12 top-level female marathon runners (Group A) and 37 student nurses who were not involved in sports (Group B). We devised a dynamometer to measure the total power exerted by the flexor muscles of the 5 toes of a single foot (total flexor power) and the combined power of the abductors of the big (1st) and little (5th) toes (abductor power). In Group A, the total flexor power was 14.3 +/- 5.3 kg in the right foot and 15.4 +/- 4.7 kg in the left foot. The abductor power was 1.9 +/- 1.8 kg in the right foot and 2.2 +/- 1.9 kg in the left foot. In Group B, total flexor power was 18.3 +/- 6.7 kg in the right foot, while the abductor power was 1.9 +/- 1.7 kg. The subjects from Group A with an arch index &#60; 1.0 (n = 8) or &#62; 1.0 (n = 4) were respectively classified as Group I and Group II. In Group I, total flexor power was 14.9 +/- 5.3 kg (right) and 15.5 +/- 5.2 kg (left), while the abductor power was 2.6 +/- 1.9 kg (right), and 3.1 +/- 1.7 kg (left). In Group II, the total flexor power was 13.2 +/- 5.8 kg (right) and 15.1 +/- 4.2 kg (left), while the abductor power was 0.7 +/- 0.6 kg (right) and 0.3 +/- 0.2 kg (left). The abductor power of toes was significantly lower in Group II than in Group I. The incidence of posteromedial shin pain was higher in Group II (75.0%) than in Group I (12.5%).</p