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The phasor measurement unit (PMU) is an essential instrument for surveillance, control, and protection of power grids because it has the ability to provide critical time-synchronized real-time voltage, current, frequency, and phase data. PMUs are being deployed for real-time behaviour monitoring of power grids. The exactness and reliability of data obtained from PMUs can be ensured if the PMUs are calibrated from a traceable PMU calibrator. The facility of Phasor Measurement Unit Calibration System (PMU-CAL) has been established at the CSIR-National Physical Laboratory, New Delhi, in 2018 and is traceable to the national standards. By testing and calibrating PMUs according to the latest IEEE standard, PMU-CAL provides the best solution for PMU users, manufacturers, and energy suppliers. This paper presents the results of reference standard PMU calibrated for the measurement class carried out in the last five years from 2018 to 2022. The results show that the reference standard is highly stable and complies with the IEEE standard. With traceable measurements, once calibration is complete, all PMUs deployed in a country's grid will provide precise and reliable data that will help to increase efficiency, improve reliability, and enhance the quality of the power grid. [ABSTRACT FROM AUTHOR]

There is growing interest in infections occurring after transcatheter aortic valve implantation (TAVI). The incidence, and clinical and anatomical features suggest many similarities with prosthetic valve endocarditis. The survival of patients with an infected TAVI prosthesis is generally poor; however, only a minority of them (10%) have undergone treatment with surgical explantation of the infected prosthesis. A literature search was performed using online databases. Papers reporting surgical treatment of TAVI prosthesis infections were retrieved, focusing on pre- and intraoperative characteristics and early outcome. Thirty-seven papers ultimately provided information on 107 patients. Their mean ± standard deviation (SD) age was 76 ± 8 years and 72% were male. The mean ± SD time interval between the TAVI procedure and reoperation was 10 ± 10 months. Annular abscess formation was described in 34% of cases and mitral valve involvement in 31%. All patients underwent TAVI prosthesis explantation and surgical aortic valve replacement; concomitant mitral valve replacement was necessary in 22% of cases. Postoperative in-hospital mortality was 28%. Surgical explantation of infected TAVI prostheses was associated with a high postoperative mortality, although these initial experiences included elderly and high-risk patients. Considering the expansion of TAVI procedures towards younger and lower-risk patients, surgical treatment of TAVI endocarditis may represent the best option for a life-saving procedure. [ABSTRACT FROM AUTHOR]

Interspecific somatic hybrids between the dihaploid Solanum tuberosum and the wild species S. pinnatisectum Dun. were produced via protoplast fusion. Protoplast isolation, electrofusion, culture of post-fusion products and regeneration of calli/shoots were undertaken following optimized protocols. Regenerants were characterized for hybridity, ploidy and resistance to Phytophthora infestans (Mont.) de Bery, causal fungal pathogen of late blight disease. From a total of 126 regenerated macrocalli, 12 somatic hybrids were confirmed by possessing species-specific diagnostic bands of their corresponding parents as revealed by RAPD, SSRs and cytoplasmic-DNA analyses. Tetraploid status of the 12 hybrids was determined using flow cytometry analysis. Intermediate phenotypes for leaf, flower, and tuber characteristics and high male fertility were observed in field-grown hybrid plants. Hybrids were highly resistant to foliage late blight based on field assessment for two seasons. In contrast, moderate level of resistance to foliage blight was observed in hybrids based on the detached leaf assay under laboratory conditions. Overall, somatic hybrids with moderate levels of resistance to foliage blight were identified, and these will be useful for in situ hybridization in potato breeding efforts. [ABSTRACT FROM AUTHOR]

Development of hypoxia-targeted therapies has stimulated the search for clinically applicable noninvasive markers of tumour hypoxia. Here, we describe the validation of [(18)F]fluoroetanidazole ([(18)F]FETA) as a tumour hypoxia marker by positron emission tomography (PET). Cellular transport and retention of [(18)F]FETA were determined in vitro under air vs nitrogen. Biodistribution and metabolism of the radiotracer were determined in mice bearing MCF-7, RIF-1, EMT6, HT1080/26.6, and HT1080/1-3C xenografts. Dynamic PET imaging was performed on a dedicated small animal scanner. [(18)F]FETA, with an octanol-water partition coefficient of 0.16+/-0.01, was selectively retained by RIF-1 cells under hypoxia compared to air (3.4- to 4.3-fold at 60-120 min). The radiotracer was stable in the plasma and distributed well to all the tissues studied. The 60-min tumour/muscle ratios positively correlated with the percentage of pO(2) values <5 mmHg (r=0.805, P=0.027) and carbogen breathing decreased [(18)F]FETA-derived radioactivity levels (P=0.028). In contrast, nitroreductase activity did not influence accumulation. Tumours were sufficiently visualised by PET imaging within 30-60 min. Higher fractional retention of [(18)F]FETA in HT1080/1-3C vs HT1080/26.6 tumours determined by dynamic PET imaging (P=0.05) reflected higher percentage of pO(2) values <1 mmHg (P=0.023), lower vessel density (P=0.026), and higher radiobiological hypoxic fraction (P=0.008) of the HT1080/1-3C tumours. In conclusion, [(18)F]FETA shows hypoxia-dependent tumour retention and is, thus, a promising PET marker that warrants clinical evaluation. [ABSTRACT FROM AUTHOR]

Eight normal subjects (3 females and 5 males) were studied using intravenous L-C] deprenyl and positron emission tomography. In a single blind study one subject received tracer alone, one subject received an oral pre-dose of 20 mg of L-deprenyl and 6 subjects received oral pre-doses of 10 to 50 mg of a novel reversible MAO-B inhibitor (Ro 19-6327). Dynamic PET scans beginning 12 h after the oral dose were collected over 90 min and arterial blood was continuously sampled. Data analysis was modelled for two tissue compartments and using an iterative curve fitting technique the value of the rate constant for irreversible binding of L-[C] deprenyl to MAO-B (k3) in whole brain was obtained for each subject. The dose response curves obtained indicated that a dose of at least 0.48 mg·kg of Ro 19-6327 was necessary for >90% decrease in whole brain k3. Inhibition of MAO-B in platelets isolated from blood samples taken at the time of scanning correlated strongly with decrease in whole brain k3 ( r=0.949). The results indicate that PET can be used to determine the dose of Ro 19-6327 necessary to inhibit >90% of brain MAO-B. This technique is an attractive alternative to traditional large scale patient-based dose-finding studies. Moreover it is shown that inhibition of platelet MAO-B can be used as a marker for central MAO-B inhibition with Ro 19-6327. [ABSTRACT FROM AUTHOR]

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