44 research outputs found

    PARAMETRIC STUDY ON PARETO, NASH MINMAX DIFFERENTIAL GAME

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    In parametric analysis, which often referrers to parametric optimization or parametric programming, a perturbation parameter is introduction to the optimization problem, which means that the coefficients in the objective function of the problem and On the other hand of the constraints are perturbed. In this paper, we present the qualitative and quantitative analysis of adapted approach of Min-Max differential game of fixed duration with general parameters in the cost functions and constrains between multiple players playing dependently (the Pareto concept) and others independently (the Nash concept), the solvability set and the stability sets of the first and the second kind are defined and algorithms for determining these sets are presented

    A RECENT APPROACH TO CONTINUOUS TIME OPEN LOOP STACKELBERG DYNAMIC GAME WITH MIN-MAX COOPERATIVE AND NONCOOPERATIVE FOLLOWERS

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    Stackelberg games play an extremely important role in such fields as economics, management, politics and behavioral sciences. There exists extensive literature about static optimization problems. However, the studies on dynamic optimization problems are relatively scarce in spite of the importance in explaining and predicting some phenomena rationally. In this paper, new approach of continuous time open loop stackelberg differential game introduced with a min-max game (secure concept) between multiple followers playing dependently (the pareto followers) and others independently (the nash followers), the problem formulation is presented with an example for the solution of the game

    A RECENT APPROACH TO CONTINUOUS TIME OPEN LOOP STACKELBERG DYNAMIC GAME WITH MIN-MAX COOPERATIVE AND NONCOOPERATIVE FOLLOWERS

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    Stackelberg games play an extremely important role in such fields as economics, management, politics and behavioral sciences. There exists extensive literature about static optimization problems. However, the studies on dynamic optimization problems are relatively scarce in spite of the importance in explaining and predicting some phenomena rationally. In this paper, new approach of continuous time open loop stackelberg differential game introduced with a min-max game (secure concept) between multiple followers playing dependently (the pareto followers) and others independently (the nash followers), the problem formulation is presented with an example for the solution of the game

    GWAS of QRS duration identifies new loci specific to Hispanic/Latino populations

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    Background The electrocardiographically quantified QRS duration measures ventricular depolarization and conduction. QRS prolongation has been associated with poor heart failure prognosis and cardiovascular mortality, including sudden death. While previous genome-wide association studies (GWAS) have identified 32 QRS SNPs across 26 loci among European, African, and Asian-descent populations, the genetics of QRS among Hispanics/Latinos has not been previously explored. Methods We performed a GWAS of QRS duration among Hispanic/Latino ancestry populations (n = 15,124) from four studies using 1000 Genomes imputed genotype data (adjusted for age, sex, global ancestry, clinical and study-specific covariates). Study-specific results were combined using fixed-effects, inverse variance-weighted meta-analysis. Results We identified six loci associated with QRS (P<5x10-8), including two novel loci: MYOCD, a nuclear protein expressed in the heart, and SYT1, an integral membrane protein. The top SNP in the MYOCD locus, intronic SNP rs16946539, was found in Hispanics/Latinos with a minor allele frequency (MAF) of 0.04, but is monomorphic in European and African descent populations. The most significant QRS duration association was with intronic SNP rs3922344 (P = 1.19x10-24) in SCN5A/SCN10A. Three other previously identified loci, CDKN1A, VTI1A, and HAND1, also exceeded the GWAS significance threshold among Hispanics/Latinos. A total of 27 of 32 previously identified QRS duration SNPs were shown to generalize in Hispanics/Latinos. Conclusions Our QRS duration GWAS, the first in Hispanic/Latino populations, identified two new loci, underscoring the utility of extending large scale genomic studies to currently under-examined populations

    Severe neurological outcomes after very early bilateral nephrectomies in patients with autosomal recessive polycystic kidney disease (ARPKD)

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    To test the association between bilateral nephrectomies in patients with autosomal recessive polycystic kidney disease (ARPKD) and long-term clinical outcome and to identify risk factors for severe outcomes, a dataset comprising 504 patients from the international registry study ARegPKD was analyzed for characteristics and complications of patients with very early (� 3 months; VEBNE) and early (4�15 months; EBNE) bilateral nephrectomies. Patients with very early dialysis (VED, onset � 3 months) without bilateral nephrectomies and patients with total kidney volumes (TKV) comparable to VEBNE infants served as additional control groups. We identified 19 children with VEBNE, 9 with EBNE, 12 with VED and 11 in the TKV control group. VEBNE patients suffered more frequently from severe neurological complications in comparison to all control patients. Very early bilateral nephrectomies and documentation of severe hypotensive episodes were independent risk factors for severe neurological complications. Bilateral nephrectomies within the first 3 months of life are associated with a risk of severe neurological complications later in life. Our data support a very cautious indication of very early bilateral nephrectomies in ARPKD, especially in patients with residual kidney function, and emphasize the importance of avoiding severe hypotensive episodes in this at-risk cohort. © 2020, The Author(s)

    Does insulin like growth factor-1 (IGF-1) deficiency have a "protective" role in the development of diabetic retinopathy in Thalassamia major patients?

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    Rationale: Both insulin and IGF-1 have been implicated in the control of retinal endothelial cell growth, neovascularization and diabetic retinopathy. Recent findings have established an essential role for IGF-1 in angiogenesis and demonstrated a new target for control of retinopathy that explains why diabetic retinopathy initially increases with the onset of insulin treatment Objective: This cross-sectional study was designed to give insights into relationship between Insulin-Growth-Factor 1 (IGF-1) levels and diabetic retinopathy (DR) in a sample of thalassemia major (TM) patients with insulin dependent diabetes mellitus (IDDM). This relation was not previously evaluated, despite the fact that both diseases co-exist in the same patient. The study also describes the clinical and biochemical profile of the associated complications in TM patients with and without IDDM. Design: A population-based cross-sectional study. Participants: The study includes 19 consecutive TM patients with IDDM and 31 age- and sex-matched TM patients without IDDM who visited our out-patient clinics for an endocrine assessment Methods: An extensive medical history, with data on associated complications and current medications, was obtained. Blood samples were drawn in the morning after an overnight fast to measure the serum concentrations of IGF-1, glucose, fructosamine, free thyroxine (FT4), thyrotropin (TSH) and biochemical analysis. Serologic screening assays for hepatitis C virus seropositivity (HCVab and HCV-RNA) were also evaluated; applying routine laboratory methods. Plasma total IGF-1 was measured by a chemiluminescent immunometric assay (CLIA) method. Ophthalmology evaluation was done by the same researcher using stereoscopic fundus biomicroscopy through dilated pupils. DR was graded using the scale developed by the Global Diabetic Retinopathy Group. Iron stores were assessed by direct and indirect methods. Results: Eighteen TM patients with IDDM (94.7 %) and ten non-diabetic patients (32.2 %) had IGF-1 levels below the 2.5th percentile of the normal values for the Italian population. The mean serum IGF-1 concentrations were significantly lower in the diabetic versus the non-diabetic TM groups (p < 0.001). DR was present in 4 (21 %) of 19 TM patients with IDDM and was associated with the main classical risk factors, namely inefficient glycemic control and duration of the disease but not hypertension. Using the scale developed by the Global Diabetic Retinopathy Group, the DR in our patients was classified as non proliferative diabetic retinopathy (NPDR). Only a few numbers of microaneurysms [1-3] were detected. Our data also confirm the strong association of IDDM in TM patients with other endocrine and non-endocrine complications

    Acquired hypogonadotropic hypogonadism (AHH) in thalassaemia major patients: An underdiagnosed condition?

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    Introduction. In males, acquired hypogonadotropic hypogonadism (AHH) includes all disorders that damage or alter the function of gonadotropin-releasing hormone (GnRH) neurons and/or pituitary gonadotroph cells. The clinical characteristics of AHH are androgen deficiency and lack, delay or halt of pubertal sexual maturation. AHH lead to decreased libido, impaired erectile function, and strength, a worsened sense of well-being and degraded quality of life (QOL). Patients and methods. We studied 11 adult men with thalassemia major (TM) aged between 26 to 54 years (mean ± SD: 34.3 ± 8.8 years) with AHH. Twelve age- and sex-matched TM patients with normal pubertal development were used as a control group. All patients were on regular transfusions and iron chelation therapy. Fasting venous blood samples were collected two weeks after transfusion to measure serum concentrations of IGF-1, free thyroxine (FT4), thyrotropin (TSH), cortisol, luteinizing hormone (LH), follicle stimulating hormone (FSH), total testosterone (TT), prolactin and estradiol (E2), glucose, urea, creatinine and electrolytes (including calcium and phosphate). Liver functions and screening for hepatitis C virus seropositivity (HCVab and HCV-RNA) were performed. Iron status was assessed by measuring serum ferritin levels, and evaluation of iron concentrations in the liver (LIC) and heart using MRI- T2*. Bone mineral density was measured at the lumbar spine (L1-L4) for all patients with AHH by dual energy X-ray absorptiometry (DXA) using Hologic QDR 4000 machine. Results. The mean basal serum LH and FSH concentrations in AHH patients were 2.4 ± 2.2 IU/L and 1.2 ± 0.9 IU/L respectively; these, values were significantly lower compared to the control group. Semen analysis in 5 patients with AHH showed azoospermia in 3 and oligoasthenozoospermia in 2. The percentage of patients with serum ferritin level >2000 ng/ml (severe iron load) was significantly higher in AHH patients compared to controls, 5/11 (45.4 %) versus1/12 (8.3%), p=0.043. Heart iron concentrations (T2* values) were significantly lower in AHH patients compared to controls (p=0.004). Magnetic resonance imaging in the 3 azoospermic patients revealed volume loss and reduction of pituitary signal intensity. Heart T2* values were significantly reduced in the AHH group vs. the controls (p=0.004). On the other hand, liver iron concentration (mg/g dry weight) was not different between the two groups of TM patients. Using DXA, 63.6 % (7/11) of patients with AHH were osteoporotic, and 36.3 % (4/11) were osteopenic. Conclusions. In this cohort of thalassemic patients iron overload and chronic liver disease appear to play a role in the development of AHH. Treatment of AHH in TM patients is a vital and dynamic field for improving their health and QOL. Early identification and management of AHH are very crucial to avoid long-term morbidity, including sexual dysfunction and infertility. Therapy aims to restore serum testosterone levels to the mid-normal range. Many exciting opportunities remain for further research and therapeutic development

    Cystinosis: a review

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    Cystinosis is the most common hereditary cause of renal Fanconi syndrome in children. It is an autosomal recessive lysosomal storage disorder caused by mutations in the CTNS gene encoding for the carrier protein cystinosin, transporting cystine out of the lysosomal compartment. Defective cystinosin function leads to intra-lysosomal cystine accumulation in all body cells and organs. The kidneys are initially affected during the first year of life through proximal tubular damage followed by progressive glomerular damage and end stage renal failure during mid-childhood if not treated. Other affected organs include eyes, thyroid, pancreas, gonads, muscles and CNS. Leucocyte cystine assay is the cornerstone for both diagnosis and therapeutic monitoring of the disease. Several lines of treatment are available for cystinosis including the cystine depleting agent cysteamine, renal replacement therapy, hormonal therapy and others; however, no curative treatment is yet available. In the current review we will discuss the most important clinical features of the disease, advantages and disadvantages of the current diagnostic and therapeutic options and the main topics of future research in cystinosis

    Reducibility study of Rossetta ilmenite ore briquettes and powder with coke breeze at 800-1100°C

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    Ilmenite ore fine and coke breeze as reduced material were briquetted with different amounts of organic materials such as molasses or pitch were studied in this investigation. The produced briquettes at reasonable condition were reduced in nitrogen atmosphere at temperature range 800 - 1100oC to determine the factors controlling the reduction and to determine the controlling mechanism. Also ilmenite ore fine with coke breeze were reduced at the same temperature range in nitrogen atmosphere without briquetting process, for the sake of comparison

    Clinical utility of chitotriosidase enzyme activity in nephropathic cystinosis

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    Contains fulltext : 138675.pdf (publisher's version ) (Open Access)BackgroundNephropathic cystinosis is an inherited autosomal recessive lysosomal storage disorder characterized by the pathological accumulation and crystallization of cystine inside different cell types. WBC cystine determination forms the basis for the diagnosis and therapeutic monitoring with the cystine depleting drug (cysteamine). The chitotriosidase enzyme is a human chitinase, produced by activated macrophages. Its elevation is documented in several lysosomal storage disorders. Although, about 6% of Caucasians have enzyme deficiency due to homozygosity of 24-bp duplication mutation in the chitotriosidase gene, it is currently established as a screening marker and therapeutic monitor for Gaucher inverted question marks disease.MethodsPlasma chitotriosidase activity was measured in 45 cystinotic patients, and compared with 87 healthy controls and 54 renal disease patients with different degrees of renal failure (CKD1-5). Chitotriosidase levels were also correlated with WBC cystine in 32 treated patients. Furthermore, we incubated control human macrophages in-vitro with different concentrations of cystine crystals and monitored the response of tumor necrosis factor-alpha (TNF- inverted question mark) and chitotriosidase activity. We also compared plasma chitotriosidase activity in cystinotic knocked-out (n inverted question mark= inverted question mark10) versus wild-type mice (n inverted question mark= inverted question mark10).ResultsPlasma chitotriosidase activity in cystinotic patients (0 inverted question mark3880, median 163 nmol/ml/h) was significantly elevated compared to healthy controls (0 inverted question mark90, median 18 nmol/ml/h) and to CKD patients (0 inverted question mark321, median 52 nmol/ml/h), P inverted question mark< inverted question mark0.001 for both groups. Controls with decreased renal function had mild to moderate chitotriosidase elevations; however, their levels were significantly lower than in cystinotic patients with comparable degree of renal insufficiency. Chitotriosidase activity positively correlated with WBC cystine content for patients on cysteamine therapy (r inverted question mark= inverted question mark0.8), P inverted question mark< inverted question mark0.001. In culture, human control macrophages engulfed cystine crystals and released TNF- inverted question mark into culture supernatant in a crystal concentration dependent manner. Chitotriosidase activity was also significantly increased in macrophage supernatant and cell-lysate. Furthermore, chitotriosidase activity was significantly higher in cystinotic knocked-out than in the wild-type mice, P inverted question mark= inverted question mark0.003.ConclusionsThis study indicates that cystine crystals are potent activators of human macrophages and that chitotriosidase activity is a useful marker for this activation and a promising clinical biomarker and therapeutic monitor for nephropathic cystinosis
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