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Synchronous reference frame (SRF) control strategy for solar photovoltaic (SPV) sources is widely used to deliver maximum power to the grid. However, poor inertia support just after a disturbance and improper phase angle tracking in presence of the harmonics and system unbalance are noticed when the conventional phase‐locked loop (PLL) based SRF control structure is used. In this study, an inertia enhancement method for inverter interfaced SPV sources is proposed, which adjusts only the PLL parameters with a notch filter (NF) in the SRF controller. NF in PLL is used due to its disturbance rejection potential and accurate phase angle tracking, even during system unbalance. The dynamic equation of pseudo induced voltage (PIV) vector with respect to the point of common coupling is derived. The kinematic equation of the PIV angle vector correlates inertia contribution and inverter terminal voltage. The impact of the change in PLL parameters on inertia enhancement is analyzed by validating the proposed technique on a test system in the real‐time digital simulator. The frequency response by the proposed method has been compared with two state‐of‐art methods to prove the superiority of the proposed approach in enhancing the inertia of the SPV source in a microgrid. [ABSTRACT FROM AUTHOR]

Introduction: Bloodstream infections (BSIs) are associated with a high mortality rate of 20%-50%. Blood culture is paramount to identify causative agents of BSIs to choose an appropriate antimicrobial therapy. Objectives: The present study was undertaken to analyze the various microorganisms causing BSIs and study their antimicrobial resistance patterns in a tertiary care hospital, Eastern India. Materials and Methods: A total of 239 blood specimens from clinically suspected cases of BSIs were studied for 6 months from July 2015 to December 2015. Blood specimens were incubated in BacT/ALERT ® 3D system (bioMerieux, Durham, NC, USA) a fully automated blood culture system for detection of aerobic growth. Identification and antimicrobial susceptibility testing were conducted on VITEK ® 2 (bioMerieux, Durham, NC, USA) as per Clinical Laboratory Standards Institute guidelines. Results: Out of 239 specimens, 41 (17.2%) yielded growth of different microorganisms. From these isolates, 20 (48.8%) were Gram-negative bacilli, 18 (43.9%) were Gram-positive cocci and rest 3 (7.3%) were yeasts. Among Gram-negative bacilli, Klebsiella pneumoniae sub spp. pneumoniae (70%) was most commonly isolated. Coagulase-negative staphylococci (88.9%) were the most common isolate among Gram-positive cocci. All three Candida spp. isolated were nonalbicans Candida (two Candida tropicalis and one Candida krusei). Gram-negative isolates were least resistant to tigecycline and colistin. All Gram-positive cocci were sensitive to linezolid. Conclusion: Monitoring of data regarding the prevalence of microorganisms and its resistance patterns would help in currently prescribing antimicrobial regimens and improving the infection control practices by formulating policies for empirical antimicrobial therapy. [ABSTRACT FROM AUTHOR]

The heat transfer from the low latitudes to high latitudes is responsible for maintaining the earth’s climate dynamics. Thus, deciphering the possible mechanism driving the variability of the Indian summer monsoon (ISM) during the Holocene Epoch has been critical to understand the hydroclimatic changes of the low latitudes. Despite several efforts, the teleconnection of ISM with the global climate dynamics remains under-represented and poorly understood. The present study aims to delineate the ISM variability and its possible forcing mechanism from western India (Gujarat). In this study, a sediment core (~65 cm long) was raised from the Jaffrabad mudflat (MIT) in western Gujarat. The sediment samples were subjected to geochemical analysis to investigate paleomonsoon, paleo-sediment source and paleoweathering changes. The results show that, with the addition of intermediate sources, the sediments were principally derived from the hinterland’s Deccan basalts. Further, the study suggested a warm and wet climate due to strong ISM during 10,650−5500 cal yr BP associated with the solar as well as orbital forcings. The weak monsoon during 5500−2700 cal yr BP has been linked with southward migration of the Intertropical Convergence Zone (ITCZ) along with the increased El Niño-like conditions. Further, the wavelet analysis revealed that a combined influence of solar, orbital and North Atlantic forcings led to monsoon variability along western India, during the Holocene Epoch. By reconciling the geochemical proxies, the present study has implications in the reconstruction of paleomonsoon and establishing the possible teleconnection with the global climate system. [ABSTRACT FROM AUTHOR]