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The problem of mixed H2/H control with pole placement is considered for linear time-invariant systems. This is the problem of determining a controller for linear time-invariant systems which minimizes the H2-norm of a certain closed-loop transfor function subject to an H-norm constraint on another closed-loop transfer function and an additional constraint on the location of the closed-loop poles in the complex plane. An optimization problem is posed for the pole-constrained H2/H, problem in such a way that the objective function is expressed as a weighted sum of the actual H2 cost and its upper bound. A necessary condition for the optimization problem is derived via the Lagrange multiplier technique. The condition involves a set of highly coupled equations. By sacrificing the H2 performance, an alternative optimization problem is posed in order to simplify the necessary condition. An iterative algorithm for solving the coupled equations arising in the necessary conditions is proposed and numerical examples are presented.  相似文献   
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Poor prognosis in nasopharyngeal carcinoma patients may result from resistance to the apoptosis-inducing effect of radio- and/or chemotherapy. Apoptosis depends on proper activation of caspase 3, resulting in cleavage of key proteins like PARP-1. To investigate whether disruption of the apoptosis pathway results in therapy-resistant tumour cells, we investigated whether absence of caspase 3 activation in tumour biopsies of nasopharyngeal carcinoma patients is related to poor clinical outcome. Moreover, we investigated whether absence of caspase 3 activation is related to loss of procaspase 3 expression or expression of the apoptosis regulators p53, bcl-2 and XIAP. We studied 36 Indonesian nasopharyngeal carcinoma patients without evidence of distant metastases who were treated with curative intent by radiotherapy only. Activation of caspase 3 and expression of the different markers were determined using specific antibodies. Levels of caspase 3 activation were determined by quantifying positively staining tumour cells. Nasopharyngeal carcinoma-derived C15 and C17 tumour cells were used as control. Absence of caspase 3 activation was strongly related to a poor clinical response to radiotherapy and to a higher T and N stage, resulting in a particularly poor clinical outcome with regard to progression-free (P<0.0001) and overall survival time (P<0.0001). Absence of caspase 3 activation was significantly correlated to loss of expression of procaspase 3 (P=0.04). In nasopharyngeal carcinoma patients treated with curative intent, absence of active caspase 3-positive neoplastic cells predicts rapid fatal outcome, and is associated with poor response to radiotherapy and high T and N stage at time of presentation.  相似文献   
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We report four Indonesian cases meeting the clinical and radiological criteria for community-acquired pneumonia and other findings suggestive of leptospirosis. Quantitative PCR (qPCR) analyses of serum and urine samples and serology confirmed the diagnosis of leptospirosis in each. Results of qPCR analysis of throat swabs were concordant with those obtained with acute-phase serum samples, which suggests its potential for use as a noninvasive diagnostic tool for leptospirosis.  相似文献   
6.

BACKGROUND/OBJECTIVES

The relationship between food intake and nutritional status has been clearly established. Yet, there are only limited studies on food intake among family members and their nutritional status. The study examined the relationship between intra-household food distribution and coexistence of dual forms of malnutrition (DFM) in the same household.

SUBJECTS/METHODS

Households with a malnourished child and overweight mother were categorized as DFM. Intra-household food distribution among family members was reported using ratios, which are a measure of individual intakes as compared to all household member intakes adjusted to RDA.

RESULTS

A 1,899 families were included in the study. The prevalence of DFM was 29.8% (95%CI 26.5-31.2). Children consumed lower amounts of energy (OR 1.34; 95%CI 1.06-1.69, P = 0.011), carbohydrates (OR 1.2; 95%CI1.03-1.61, P = 0.022), protein (OR 1.3; 95%CI 1.03-1.64, P = 0.026), and fat (OR 1.3; 95%CI 1.05-1.66, P = 0.016) than their mothers and other family members. In contrast, mothers consumed more carbohydrates than children and other family members (OR1.24; 95%CI 1.02-1.51, P = 0.03).

CONCLUSIONS

This study is the first to report on the food distribution among family members and its relationship with occurrence of DFM in Indonesia. The results confirm the occurrence of an unequal food distribution between children and mothers, which increases risk of DFM in the household. The results also demonstrate that nutritional education at the household level is important to increase awareness of the impact of DFM.  相似文献   
7.
In this study, carbon dots synthesized from bamboo leaf cellulose were used simultaneously as a staining agent and for doxorubicin delivery to target cancer cells. Owing to their nontoxic properties, the production of carbon dots from bamboo leaves is a green approach involving optimized application of bamboo tree waste. For multifunctional applications, the carbon dots were modified with 4-carboxybenzylboronic acid and doxorubicin to improve target specificity and drug delivery to HeLa tumor cells. The resulting modified carbon dots were characterized using different analytical techniques, which showed that they were biocompatible, nontoxic, and highly stable over a wide range of pH values and at high ionic strengths. Furthermore, in vitro confocal microscopy studies demonstrated their blue fluorescence and cellular pathway for entering HeLa cells via folate receptor-mediated endocytosis. Cell viability data and flow cytometry results also confirmed the selective uptake of the carbon dots by HeLa cells, which significantly enhanced cell cytotoxicity.

In this study, carbon dots synthesized from bamboo leaf cellulose were used simultaneously as a staining agent and for doxorubicin delivery to target cancer cells.  相似文献   
8.

Background  

A community health assessment (CHA) is used to identify and address health issues in a given population. Effective CHA requires timely and comprehensive information from a wide variety of sources, such as: socio-economic data, disease surveillance, healthcare utilization, environmental data, and health resource allocation.  相似文献   
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