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In this work, we aimed to study whether myocardial infarction associated transcript (MIAT) exerts a regulative effect on cardiac hypertrophy via acting as a miR-150 sponge.Cardiac hypertrophy was induced using Angiotensin II (Ang II). MIAT and miR-150 expression were quantified using qRT-PCR. Rat heart-derived H9c2 cells were used as the in vitro model. Cardiac hypertrophic features were assessed by quantifying cardiac hypertrophic genes and measurement of cell surface, protein synthesis and total protein content.MIAT is significantly increased in Ang II induced cardiac hypertrophy in a mouse model and in H9c2 cells. MIAT siRNA substantially alleviated the Ang II induced upregulation of ANP, BNP and β-MHC in H9c2 cells and markedly attenuated the Ang II induced increase of the cell surface area and the protein synthesis. MIAT overexpression in H9c2 cells significantly reduced the miR-150 expression. MIAT inhibition also partly restored the miR-150 levels under Ang II treatment. MiR-150 overexpression could attenuate the Ang II induced upregulation of hypertrophic marker genes and suppress the Ang II induced hypertrophic phenotypes of the cells.MIAT is significantly increased in Ang II induced cardiac hypertrophy and contributes to the pathological development. MIAT can suppress miR-150 expression in cardiomyocytes and miR-150 is a downstream effector of MIAT in the development of cardiac hypertrophy.

Most of the infrastructure services in India are government-owned and supervised. In order to attract private investment to other sectors, the government introduced the institution of independent regulation into electricity and is considering doing so in such sectors as coal, and oil and gas. Electricity regulators have been in place at the Centre and the states for periods varying from two to six years and have been given powers to regulate tariffs, transmission, and certain private investments. They are enjoined to promote competition, efficiency, and economy in the sector, encourage private investment, and safeguard consumer interest. They have the contradictory objectives of making the sector financially viable in order to attract investment, and yet improve the availability, accessibility, and affordability of electricity. They have to perform their functions through government-owned enterprises. This has posed difficulties in terms of inadequate and inaccurate technical and financial information, governments supporting the utilities in bypassing the regulators, defiance of regulatory orders, non-compliance, and frequent challenges in courts. Regulators and their staff tend to be people drawn from government service precluding fresh thinking or independence from government practices. While the courts have on the whole been supportive of the regulatory orders, decisions have taken time and caused delays in the implementation of much-needed changes.

A Lower Hybrid Current Drive (LHCD) system would be the prime method to drive current in SST-1. The LHCD system is based upon two TH2103D klystrons of M/s Thomson CSF at 3.7 GHz capable of delivering 500 kW CW microwave power. The klystrons have been commissioned and deliver the microwave power through two standard WR-284 waveguides. It is electrically isolated from the main system using DC breaks. Two high power circulators protect the tube from high reflection. Directional couplers measure forward and reflected power in the system. The output power is deposited on two matched dummy loads during testing. In the event of arcing or any other fault, the high voltage from the klystron is removed in less than 5 μs, with the help of a crowbar system, based on a pressurized rail gap switch, for the protection of the klystron. High power (up to 200 kW), 1000-s tests of two klystrons have been conducted and detailed test results are described in this paper. It also describes the high power microwave system at 3.7 GHz that is being used to test the high power microwave components, being designed and fabricated for use in the LHCD system on SST-1.

In this paper, the implementation of a phase retrieval algorithm for determining the phase profile of gyrotron output beams from measured intensity patterns at different planes is described along with a novel mode estimation technique based on a surface matching algorithm. A simulated Gaussian beam at different planes is considered as input of the phase retrieval algorithm. The proposed mode estimation technique supports the accurate mode estimation of different linearly polarized modes present in gyrotron output RF beam.

Polymer Electrolyte Membrane (PEM) fuel cells have received increasing attention because they are widely regarded as a potential future stationary and mobile power sources. In this paper, one-dimensional, steady state model for PEM fuel cell stack is developed in MATLAB environment and the effect of various overpotentials on the polarization and the efficiency of fuel cell are studied. At low current draw, there is a sudden increase in activation overpotential due to the slow electron transfer rate and a portion of the electrode voltage is lost to compensate for the lack of electro-catalytic activity. At all current draw, ohmic losses are linear with current density due to the low conductivity of membrane. At higher current draw, the electrochemical reactions are hindered by the water generated at the cathode and voltage drops. Efficiency drops with increasing power density; hence there is a trade-off between high power and high efficiency. Fuel cell system designers must select the desired operating range according to whether efficiency or power is paramount for the given application.

Prof MV Nadkarni in ‘Ethics for our Times’ says that ethical propositions apply to everyone. Ethics like Economics, involves choice between different kinds of life. It promotes the welfare of all. Ethics is not meant only for individuals acting in isolation. It is in the 21st century that people have realized the true interdependence of all people in the world. Carbon emissions and climate change have led to understanding that development in one part of the world can harm others and in the future as well.

Hyperkinesis is associated with deficits of attention (poor allocation of attention resources, susceptibility to interference and perseveration); vigilance and perceptual sensitivity. Three boys aged 7-8 years with simple hyperkinesis were given cognitive tasks to improve the above functions in daily one hour sessions for a month. The children improved significantly in the above functions and behaviour. Three other children aged 5-8 years with simple hyperkinesis who were on medication improved only slightly in their behaviour during this period. Behavioural intervention and parental counselling were additional inputs to the children in both groups. Neuropsychological remediation combined with parental counselling and behavioural intervention shows promise in treating hyperactive children.

Alcoholism is associated with impairment of information processing attention, memory and concept formation, which hamper the patients response to psychotherapy aimed at treating alcoholism. We improved cognitive functioning in abstinent alcoholics through cognitive retraining. Eight detoxified male alcoholics, comparable on age, education, marital status, medication and years of alcohol consumption were assigned, four each to the treatment and control groups. Cognitive retraining given to the treatment group improved attention, information processing, memory, planning and reasoning. Daily, individual, one hour sessions were conducted for six weeks. Patients in the control groups were seen weekly once and counselled if necessary. In the treatment group, significant improvement of information processing, memory, and reduction of neuropsychological deficits resulted from retraining. Control group showed no changes in cognitive function. Family functioning and long term abstinence were not influenced by cognitive retraining. Neuropsychological rehabilitation is effective in improving cognitive deficits of abstinent alcoholics.

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This Paper reviews the design and functionality of the 24MW 170GHz electron cyclotron heating and current drive system being planned for the ITER Tokamak. The sub-systems (power supplies, gyrotrons, transmission lines and launcher antennas) are described based on present day technologies, while on-going R&D provides component and sub-system testing with the possibility of increasing the reliability of the overall EC system. Modifications to the steering ranges of the launching antennas are under investigation that can improve the functional capabilities of the EC system without increasing cost and relaxing the engineering constraints.

A 26 MW Electron Cyclotron Heating and Current Drive (EC H&CD) system is to be installed for ITER. The main objectives are to provide, start‐up assist, central H&CD and control of MHD activity. These are achieved by a combination of two types of launchers, one located in an equatorial port and the second type in four upper ports. The physics applications are partitioned between the two launchers, based on the deposition location and driven current profiles. The equatorial launcher (EL) will access from the plasma axis to mid radius with a relatively broad profile useful for central heating and current drive applications, while the upper launchers (ULs) will access roughly the outer half of the plasma radius with a very narrow peaked profile for the control of the Neoclassical Tearing Modes (NTM) and sawtooth oscillations. The EC power can be switched between launchers on a time scale as needed by the immediate physics requirements. A revision of all injection angles of all launchers is under consideration for increased EC physics capabilities while relaxing the engineering constraints of both the EL and ULs. A series of design reviews are being planned with the five parties (EU, IN, JA, RF, US) procuring the EC system, the EC community and ITER Organization (IO). The review meetings qualify the design and provide an environment for enhancing performances while reducing costs, simplifying interfaces, predicting technology upgrades and commercial availability. In parallel, the test programs for critical components are being supported by IO and performed by the Domestic Agencies (DAs) for minimizing risks. The wide participation of the DAs provides a broad representation from the EC community, with the aim of collecting all expertise in guiding the EC system optimization. Still a strong relationship between IO and the DA is essential for optimizing the design of the EC system and for the installation and commissioning of all ex‐vessel components when several teams from several DAs will be involved together in the tests on the ITER site.

Since the end of EDA, the design of the Electron Cyclotron Heating and Current Drive (ECH&CD) system has been modified to respond to progress in physics understanding and change of interface conditions. Nominal RF power of 20 MW is shared by four upper launchers or one equatorial launcher RF beams are steered by front steering mirrors providing wide sweeping angle for the RF beam. DC high voltage power supply may be composed of IGBT pulse step modulators because of high frequency modulation and design flexibility to three different types of 170 GHz gyrotrons provided by three parties. The RF power from the 170 GHz gyrotron is transmitted to the launcher by 63.5 mmφ corrugated waveguide line and remotely switched by a waveguide switch between the upper launcher and the equatorial launcher. The ECH&CD system has also a start‐up sub‐system for assist of initial discharge composed of three 127.5 GHz gyrotrons and a dedicated DC high voltage power supply. Three of transmission lines are shared between 170 GHz gyrotron and 127.5 GHz gyrotron so as to inject RF beam for the start‐up through the equatorial launcher. R&Ds of components for high power long pulse and mirror steering mechanism have been on‐going in the parties to establish a reliable ITER ECH&CD system.

The ICPD Plus 5 is a conference to be held in March 1999 to review progress achieved during the 5 years since the International Conference on Population and Development (ICPD). UNFPA has taken the lead in organizing a review and appraisal of how the ICPD program of action is being implemented. The review will focus upon progress made in implementing the program with particular focus upon the constraints faced by countries. Those obstacles will then hopefully be addressed over the next 5 years. UNFPA plans to undertake a series of roundtables and expert group meetings addressing priority themes of reproductive health (RH); gender equity, equality, and women's empowerment; adolescent RH; and partnership with civil society. UNFPA hopes that expert groups and roundtables will contribute to the process. Information would also be welcomed from countries on the problems they face.

Lathyrism is a non-progressive motor neuron disease produced by consumption of the excitatory amino acid, 3-N-oxalyl-L-2,3-diaminopropanoic acid (beta-ODAP). To learn more about the mechanisms underlying Lathyrism three structural analogs of beta-ODAP were synthesized. Carboxymethyl-alpha,beta-diaminopropanoic acid (CMDAP) evoked inward currents which were antagonized by APV (30 microM), but not by CNQX (10 microM). N-acetyl-alpha,beta-diaminopropanoic acid (ADAP) evoked no detectable ionic currents but potentiated N-methyl-D-aspartate (NMDA)-activated currents. The potentiation of NMDA currents by ADAP was blocked by 7-chlorokynurenic acid. Carboxymethylcysteine (CMC) did not activate any detectable ionic currents. None of the three beta-ODAP analogs produced visible symptoms of toxicity in day old chicks when administered for 2-3 consecutive days. Ligand binding studies demonstrated that all the three compounds were effective to in displacing [3H]glutamate. The maximum inhibition was 92% for CMDAP, 61% for ADAP, 65% for CMC and 99% for beta-ODAP. These data indicate that analogs of beta-ODAP may interact with glutamate receptors without producing neurotoxicity.

A comparative study of the metabolism of 1,2,3 (14)C-ODAP and 4,5 (14)C-ODAP in mice, rats and chicks has been carried out. Following oral administration of 1,2,3 (14)C-ODAP to either black or white mice, nearly 16% of the radioactivity appeared in the expired CO2 within 8 h, while in the rat only 3% of it appeared and in chicks it was less than 2%. No 14CO2 appeared in the expired air in mice given 4,5 (14)C-ODAP. Electrophoregrams of the spot urine samples from the animals given 1,2,3 (14)C-ODAP showed the presence of one radioactive metabolite (metabolite-1) in addition to ODAP. While the urine from rats and mice given 4,5 (14)C-ODAP indicated the presence of metabolite-1 as well as 14C-oxalate, in chicks, however, no 14C-oxalate was present and only metabolite-1 could be detected. The results indicate that ODAP can to some extent undergo oxidation in vivo in mice (and to a lesser extent in rats) leading to the formation of CO2 and oxalate and a similar pathway might be more prominent in humans leading to a near complete oxidation of ODAP.

Head injury is associated with psychological sequelae which impair the patient's psychosocial functioning. Information processing, attention and memory deficits are seen in head injuries of all severity. We attempted to improve deficits of focused, sustained and divided attention. The principle of overlapping sources of attention resource pools was utilised in devising the remediation programme. Tasks used simple inexpensive materials. Four head injured young adult males with post concussion syndrome underwent the retraining program for one month. The patients had deficits of focused, sustained and divided attention parallel processing, serial processing, visual scanning, verbal learning and memory and working memory. After the retraining programme the deficits of attention improved in the four patients. Serial processing improved in two patients. Parallel processing and neuropsychological deficits did not improve in any patient. The symptom intensity reduced markedly and behavioural functioning improved in three of the four patients. The results supported an association between improving attention and reduction of symptom intensity. Attention remediation shows promise as a cost effective, time efficient and simple technique to improve the psychological and psychosocial functioning of the head injured patient.

Direct evidence for the excitotoxicity of 3-N-oxalyl-L-alpha,beta-diaminopropionic acid (ODAP), the Lathyrus sativus neurotoxin has been studied by examining the binding of chemically synthesized [2,3 3H]ODAP ([3H]ODAP) to synaptic membranes. [3H]ODAP binding to membranes was mostly nonspecific, with only a very low specific binding (15-20% of the total binding) and was also not saturable. The low specific binding of [3H]ODAP remained unaltered under a variety of assay conditions. A low Bmax of 3.2 +/- 0.4 pmol/mg and Kd 0.2 +/- 0.08 microM could be discerned for the high affinity interactions under conditions wherein more than 80-90% of the binding was nonspecific. While ODAP could inhibit the binding of [3H]glutamate to chick synaptic membranes with a Ki of 10 +/- 0.9 microM, even L-DAP, a non neurotoxic amino acid was also equally effective in inhibiting the binding of [3H]glutamate. The very low specific binding of [3H]ODAP to synaptic membranes thus does not warrant considering its interactions at glutamate receptors as a significant event. The results thus suggest that the reported in vitro excitotoxic potential of ODAP may not reflect its true mechanism of neurotoxicity.

Black gram (Vigna mungo) seeds are shown to contain a lectin with certain unusual features. The lectin agglutinates only trypsinized red cells, and its sugar specificity is complex as none of the common sugars, oligosaccharides or complex polysaccharides exhibit any affinity for the lectin. The purified lectin has a molecular weight of 58 kDa and is a monomer. Unlike other plant lectins, antibodies to the P. mungo lectin do not exhibit any immunological cross reactivity. The clot forming ability of the lectin is unusual in that the clot once formed is rapidly disaggregated indicated that it induces, as yet undefined, certain membrane alterations.

From January 1986 to December 1989, seventy patients underwent mitral valve repair. Sixty-four patients had severe mitral stenosis (MS) and mitral regurgitation (MR), while six patients had severe mitral regurgitation (MR) only. The technique used was a combination of posterior semicircular annuloplasty, mitral commissurotomy and chordal shortening. There were two operative deaths. All except three of the surviving patients are asymptomatic. There has been no episode of thromboembolism. One patient has required valve replacement and two others have had a revision of the repair in the follow up period. Predischarge and late (3 months to 3 years) echocardiography suggests that the repair is satisfactory.

The lower hybrid current drive (LHCD) system is an important system in superconducting steady state tokamak (SST-1). It is used to drive and maintain the plasma current for 1000 s with a duty cycle of 17%. The LHCD system is being designed to launch 1 MW of radio frequency (rf) power at 3.7 GHz. The rf source is comprised of two high power klystron amplifiers, each capable of delivering 500 kW rf power. In this article, the results obtained during installation and commissioning of these klystrons are presented. Two klystrons (model TH2103D) have been successfully installed and commissioned on dummy loads, delivering ∼200 kW power for more than 1000 s. The maximum output power that could be obtained is limited due to the available direct current (dc) power supply. The test system is comprised of a TH2103D klystron, a low power rf (3.7 GHz/25 W) source, two high power four port circulators, two high power dual directional couplers, two arc detector systems, and two dummy water loads. To avoid rf breakdown in the rf components of the transmission line, the system has been pressurized with dry air to 3 bar. To energize and operate the klystron, a high voltage dc power supply, a magnet power supply, an ion pump power supply, a −65 kV floating anode modulator power supply, and a filament power supply are used. An arc detector unit has been installed to detect and initiate action within a few microseconds to protect the klystron, waveguides, and other rf passive components during arcing. To protect the klystron in the event of an arc, a fast responding (