Orthogonal functions approach to optimal control of delay systems with reverse time terms

Using block-pulse functions (BPFs)/shifted Legendre polynomials (SLPs) a unified approach for computing optimal control law of linear time-varying time-delay systems with reverse time terms and quadratic performance index is discussed in this paper. The governing delay-differential equations of dynamical systems are converted into linear algebraic equations by using operational matrices of orthogonal functions (BPFs and SLPs). The problem of finding optimal control law is thus reduced to the problem of solving algebraic equations. One example is included to demonstrate the applicability of the proposed approach.     

Whiteness,internationalization, and erasure: decolonizing futures from the Global South

ABSTRACT

The essay explores the mobility of Whiteness in networks of Communication Studies that posture themselves as speaking from the Global South. Depoliticized languages of de-westernizing, internationalizing, and decolonizing are often articulated by elites in North-South networks pushing neoliberal governmentality, erasing claims to radical equality that emerge from within socialist struggles in the Global South. In resistance, a radical framework of knowledge from the Global South emerges from within subaltern struggles for hegemony, achieved through (a) delinking from the metropoles of the North and (b) explicitly crafting a socialist anticolonial politics that names and dismantles Whiteness as a capitalist project.     

An Interesting Case of Polyuria in a Child

A 1 year old male child with increased frequency of urine associated with increased thirst was found to have some developmental delays. Laboratory investigations showed increased serum sodium level and serum osmolality with decreased urine osmolality. An empty sella turcica was seen in contrast brain MRI; however focal demyelinating lesion was not present. He was managed with intranasal desmopressin therapy. Developmental delays in such cases can be prevented by early referral to a tertiary health care center where laboratory and imaging facilities are available.     

Interrelationship Between Procalcitonin and Organ Failure in Sepsis

Sepsis suffers from lack of specific clinical symptoms which contribute to one of the major causes of mortality. In the present study, our aim was to evaluate the role of a recent biomarker Procalcitonin (PCT) in predicting organ dysfunction. 71 patients admitted with sepsis were included in the study. PCT levels were measured at 0, 24, 72 h and 7th day and sequential organ failure assessment score (SOFA) scores were calculated. PCT levels significantly decreased (p < 0.001) in 89.3 % of surviving patients, whereas, in 60 % non surviving patients the PCT level increased significantly (p < 0.001). A significant positive correlation between PCT and SOFA score was observed in survivors at each hour. These observations indicate that PCT concentration is significantly associated with severity of multi organ dysfunction and also helps in determining the prognosis of septic patients.     

MEDIA STUDIES AND VOCATIONALISM

University arts faculties have traditionally been reluctant to admit a vocational component into arts courses. The author's experience in teaching media at the New South Wales Institute of Technology suggests that the fears underlying this reluctance, while not completely irrational, arise from problems between academics and professionals who cannot work well together: they can be overcome if those involved behave with tact and flexibility. The approach to media studies in Australia is described.     

Estimation of Upper Limit of Normal for Serum Alanine Transaminase in Healthy South Indian Population

Alanine aminotransferase (ALT) is the most common and cost effective screening test for asymptomatic liver disease. There is paucity of data on normal ALT among healthy individuals in India. An observational cross sectional study was conducted from January to July 2013 to estimate the upper limit of normal for ALT in healthy south Indian population. Adults undergoing voluntary or pre-employment health screening were included. Those with current and past alcoholism or smoking, acute illness or hospitalization during preceding 12 months, non-steroidal anti-inflammatory or over the counter medication use within a month, current or past intake of herbal medications, any chronic medical illness, abnormal body mass index (BMI), fatty liver in ultrasound, abnormality in haemoglobin, platelet count, blood sugar, creatinine, lipid profile and thyroid function test and positive serology (Hepatitis B, C or HIV) were excluded. A total of 2600 subjects were screened. 344 were included for analysis. Mean age was 35 years in men and 34.83 years in women, with a mean BMI of 22.2 kg/m² in men and 21.8 kg/m² in women. The mean ALT in men and women were 21.87 ± 2.9 (97.5th percentile 28 U/L) and 19.35 ± 3.3 (97.5th percentile 24 U/L) respectively. In conclusion, mean and upper limit of ALT (97.5th percentile) in south Indian men was 21.87 and 28 IU/L and women were 19.35 and 24 IU/L respectively. There is a need to re-consider ALT levels in our population for better detection of individuals at risk for liver disease.     

Conservation of a room: A treatment proposal for Mark Rothko's Harvard Murals

A treatment with projected light for Mark Rothko's Harvard Murals (1962) is proposed. The group of five paintings on canvas has changed color due to the presence of a fugitive red pigment and excessive exposure to natural light in a room with large windows. For the conservation of Rothko's Harvard room, it is brought into context within his other commissions and environments. The original color of the works is determined by the digital restoration of contemporary photographs. With a camera projector system a compensation image is calculated that is projected onto the original canvas resulting in a restored color appearance. This approach of inpainting with light is compared with considerations of cleaning and inpainting in conventional conservation treatments. Overall lighting and architecture including the unusual wall color carefully chosen by Rothko play a key role in the treatment of the Mural cycle as an environment.     

The sun’s mysteries from space - I

This article in two parts presents a brief overview of the Sun’s mysteries revealed from space observations, using recent solar spacecrafts: Yohkoh, SOHO, TRACE and RHESSI.