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1.
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   
2.
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   
3.
4.
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   
5.

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   
6.
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   
7.

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   
8.
The objectives of the study were to determine the effectiveness and incidence of adverse events of ofloxacin otic solution for suppurative otitis media compared with other treatments. All randomized controlled trials and nonrandomized comparative clinical trials published from 1966 to 2000 using ofloxacin otic solution as one of the interventions were reviewed and data were extracted and analyzed. Eleven clinical trials (9 randomized and 2 nonrandomized) enrolling 1,484 adults and children were finally included in the analysis. Five studies employed clear concealment procedure in the allocation of treatment whereas evaluation of outcome was at least single-blinded in 6 trials. The probability of overall cure rate was higher with 0.3% ofloxacin otic solution than with other topical or systemic antibiotics in 9 of the studies analyzed (OR = 2.67; 95% CI = 2.04, 3.50). Resolution of secondary outcome parameters evaluated at least 1 week after treatment was higher with 0.3% ofloxacin otic solution: resolution of otalgia (4 trials; OR = 2.41; 95% CI = 1.2, 4.82); resolution of otorrhea (11 trials; OR = 2.78; 95% CI = 2.12, 3.65), and bacterial eradication rate (6 trials; OR = 3.86; 95% CI = 2.54, 5.87). A subgroup analysis of 4 studies comparing ofloxacin otic solution with antibiotic- and steroid-containing otic solution showed a higher cure rate for ofloxacin otic solution (OR = 2.73; 95% CI = 1.52, 4.90). Another subgroup analysis on 3 studies comparing ofloxacin otic solution with oral systemic antibiotics showed higher resolution of otorrhea with ofloxacin otic solution (OR = 2.78; 95% CI = 2.12, 3.65). Of 4 studies with data on adverse events, the probability of adverse events was lower with ofloxacin otic solution than with other topical antibiotics (OR = 0.28; 95% CI = 0.19, 0.42). Subgroup analysis showed that 0.3% ofloxacin otic solution showed better results in terms of overall cure rate, resolution of otorrhea, otalgia, bacterial eradication rate and incidence of adverse events. Whether due to chronic suppurative otitis media (CSOM) or draining tympanostomy tube, the overall cure rate (CSOM OR = 4.86; with tympanostomy tube OR = 2.13) and resolution of otorrhea (CSOM OR = 4.42; with tympanostomy tube OR = 1.66) were likewise in favor of 0.3% ofloxacin otic solution. The studies included in this meta-analysis showed generally homogenous results in all clinical and laboratory outcomes analyzed, except for the evaluation of adverse events. The authors conclude that 0.3% ofloxacin otic solution is better than other otic antibiotic drops and other oral antibiotics in terms of overall cure rate and resolution of secondary outcome parameters. Estimates on the beneficial effects of ofloxacin otic solution are limited to the period of study included in this review.  相似文献   
9.
We previously demonstrated that tumor necrosis factor-alpha (TNF-alpha) increased following a reduction in systemic blood flow to 60% or less of the original cardiac output using a left ventricular assist device (LVAD). The aim of this study was to investigate the effect of reducing systemic blood flow on tissue oxygenation in the gastrointestinal tract (GIT) and the consequences of this on TNF-alpha release. LVADs were implanted in 9 pigs. The aorta was clamped, and thus the LVAD flow represented the entire systemic blood flow. Plasma TNF-alpha of the superior mesenteric vein was measured at baseline and during systemic blood flow changes. Simultaneously, pH, lactate, oxygen delivery index (DO(2)I), oxygen consumption index (VO(2)I), and oxygen extraction (O(2)ER) in the GIT were measured. The pH decreased and the lactate level increased significantly (p < 0.05) at a systemic blood flow of 50% or less. The VO(2)I was positively correlated with DO(2)I. The O(2)ER increased significantly (p < 0.05) with reductions in systemic blood flow to 30% or less. There was a significant (p < 0.01) correlation between TNF-alpha and O(2)ER at levels higher than 55%. These data demonstrate that the GIT oxygenation is inadequate with a reduction in systemic blood flow to 50% and that GIT oxygenation becomes critical at a reduction of 30%. During LVAD weaning, careful attention must be given to the GIT. The pH and lactate may be good markers of the adequacy of tissue oxygenation in the GIT.  相似文献   
10.
We analyzed variations in long (L)- and middle (M)-wavelength-sensitive opsin gene loci in crab-eating monkeys. Unlike humans, most monkeys have a single L and a single M gene. Two variant genotypes, one with only one opsin gene (dichromatic) and one with tandemly arrayed multiple genes, were also found in the monkeys. However, the frequency of the former was 0.47%, and that of the latter was 5% in the monkeys, while 2% and 66%, respectively, in Caucasian males. The two variants were found only in Java Island, Indonesia, and South Thailand, respectively. The data suggest that the frequency of each genotype is different among Old World primates.  相似文献   
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