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The performance of power networks is enhanced by the penetration of solar energy, which helps to equate continuously the generation and demand power imbalance. However, the time margin that grids must adapt to unforeseen frequency fluctuations and restore generation-demand equivalency is reduced by these linkages. Consequently, it exerts the stability and performance of the power grid at risk. Thus, it becomes vital to assess real-time system data and to recognize and implement suitable remedies to maintain a healthy system performance. In order to improve grid stability in power networks that have solar energy penetration, this manuscript suggests a data driven integrated framework. The proposed approach is a two-step framework wherein the first stage assesses impending transient instability in the system through novel Instability Evaluation (IE). Step two involves creating and deploying a Decision Boundary based Control (DBC) to stabilize an unstable system following an emergency control strategy. An IE module employing short-synchronized movement data is presented for evaluating post-disturbance transient stability (TS). In the initial cycles following the fault initiation, the IE projects the impending transient instability. Next, an innovative DBC creates an emergency remedial system for unstable processes that determines the nature, magnitude and location of the remedial action. The DBC assesses pertinent action sets that it implements to sustain system stability using a proposed Decision Assisted Inference (DAI) technique. The simulation investigations validate the aptness of suggested analysis on the performance of power system with and without PV and topological variations.

Unpredictable variations in load demand and unanticipated component failures are progressively impacting the operation of modern power systems, making system evaluation more stochastic in nature. Although deterministic approaches were formerly the norm for determining system status, probabilistic approaches have greatly improved the capacity to capture the stochastic behavior characteristic of power system operations. The presented work in the paper recommends the use of probabilistic modelling approaches with deterministic approaches, highlighting their crucial function in augmenting the reliability and security of contemporary power systems to unanticipated failures. In this paper, N − 1 security criteria based reliability of the composite power system (CPS) is proposed using an integrated deterministic and probabilistic framework (D-P) considering outage of the transmission line. For the deterministic approach (DA), line overloading on available lines is determined using the static security index (SSI). For the probabilistic approach (PA), reliability indices such as expected loss of power (ELOP), expected frequency of contingency (EFOC), expected loss of load (ELOL), probability of load curtailment (PLC), and expected duration of load curtailments (EDLC) are calculated. Further, for each contingency, a performance index is determined using both approaches to assess the severity of the contingency that occurred on the power system. Based on the N − 1 security criteria based reliability analysis using an integrated D-P framework, a credible critical set of transmission lines is obtained, which can serve as important information to system operators. The proposed techniques have been tested on IEEE 24 bus reliability test system (RTS).

Solar energy penetration in power grids helps to maintain power balance between generation and demand, thus enhances power grid performance. However, these integrations reduce grids’ time margin to respond against sudden frequency changes and re-establishing generation-demand equivalency. Thereby, it poses challenges to the performance and stability of the power system. It therefore becomes increasingly important to comprehend the real-time system data, identify and initiate necessary remedies to sustain the healthy system’s operation. This article presents a data-driven unified methodology for enhancing grid stability in solar energy-penetrated power network. The proposed method is a two-stage unified framework that incorporates Prompt Instability Evaluation (PIE) to evaluate impending system transient instability in first stage. In the second stage for a system unstable operation a Decision Assisted Adaptive Control (DAAC) is developed and implemented for corrective emergency control. A novel PIE is presented to perform a post-disturbance transient stability assessment using short-synchronized moving data. The PIE assesses the upcoming transient instability within the first few cycles following fault inception. Next, a novel DAAC is proposed to design an emergency remedial scheme for identifying location (where), magnitude, and type in real-time for unstable operations. The DAAC utilizes a novel Decision Rule Based Inference (DRBI) to evaluate suitable action sets that may be deployed by the DAAC to sustain system stability. The simulation results demonstrate the suitability of the proposed study on the system’s performance in the absence/presence of solar energy with topological variations.

Introduction: It is estimated that hypertension (HTN) increases the risk at least twofold for cardiovascular diseases including coronary artery diseases, congestive heart failure/stroke (ischemic and hemorrhagic), renal failure, and peripheral arterial disease. In wide consensus, HTN is considered Vyanabala Vaishamya by recent Ayurvedic scholars. The aim of the study was to evaluate the effect of an Ayurvedic formulation and Nidana Parivarjana in the management of Vyanabala Vaishamya with special reference to Stage 1 primary HTN as per 8th JNC criteria. Methods: The present study was a randomized, interventional, two-arm, open-level, 30-day clinical trial on Vyanabala Vaishamya (primary HTN). Twenty-five patients in Group A were administered Ayurvedic formulation and 25 patients in Group B were administered Ayurvedic formulation along with Nidana Parivarjana (avoidance of causative factors) decided as per Ayurveda principles. Results: Ayurvedic formulation alone lowered systolic blood pressure (BP) mean from 150.087 (standard deviation [SD] ± 6.331) to 142.478 (SD ± 6.842) and diastolic BP mean from 93.609 (SD ± 3.539) to 89.522 (SD ± 3.566), while Ayurvedic formulation with Nidana Parivarjana lowered systolic BP mean from 151.000 (SD ± 5.800) to 136.174 (SD ± 5.449) and diastolic BP mean from 93.652 (SD ± 3.406) to 85.435 (SD ± 3.678). Although the reductions in BPs of both the groups were statistically highly significantly (P < 0.001), Ayurvedic formulation with Nidana Parivarjana was more effective in lowering the BPs than Ayurvedic formulation alone as found on intergroup comparison (P < 0.001). Conclusion: Ayurvedic formulation with Nidana Parivarjana was more effective in primary HTN than Ayurvedic formulation alone. It also proved that Nidana Parivarjana has a significant role in the management of Vyanabala Vaishamya, i.e., primary HTN.

Background and study aims Although endoscopic ultrasound (EUS)-guided fine-needle aspiration (EUS-FNA) is an established modality for pathological sampling of pancreatic and biliary lesions, limited data are available on the diagnostic value of EUS-FNA for evaluation of gallbladder mass lesions, a common cause of obstructive jaundice. We aimed to evaluate the usefulness of EUS-FNA for diagnosis of gallbladder mass lesions presenting with biliary obstruction. Patients and methods This study was a retrospective analysis of data from patients who had undergone EUS-FNA for gallbladder mass lesions. FNA was performed on either a gallbladder mass, metastatic node or liver lesions. Outcome measures were diagnostic yield of EUS FNA and adverse events. Results From April 2011 to August 2018, 101 patients with gallbladder mass lesions with biliary obstruction underwent EUS-FNA. The final diagnosis was malignancy in 98, benign disease in one, and two patients were lost to follow-up. EUS-FNA confirmed the diagnosis in 89 of 98 patients with malignancy (sensitivity 90.81 %); was false negative in nine of 98 cases with malignancy; and was truly negative in the solitary patient with benign disease (specificity 100 %). Positive predictive value, negative predictive value (NPV), and accuracy were 100 %, 10 %, and 90.90 %, respectively. Two patients had self-limiting pain. Conclusion EUS-FNA is a sensitive tool for evaluation of gallbladder mass lesions presenting with obstructive jaundice. However, because of low NPV, lesions in which FNA is negative should be further evaluated.

One of the smartest evolution in the electrical power system is the integration of various renewable sources. It is an effective way to cater consumers growing power demands. The intermittency issues in renewable sources may lead to generation and demand imbalance. This imbalance creates various issues like frequency fluctuations, voltage variation, power quality problem and so on. This study proposes a method to reduce the frequency deviation. More the electric vehicles (EVs) in this system, then more the mobile storage devices for vehicle to grid (V2G). The charging/discharging rates of EVs are controlled as per the regulation signal coming from the system operator. The proposed scheme has been simulated using the frequency regulation data acquired from PJM. The proposed algorithm controls the total charging/discharging power based on the regulation signal and this is used to modify the charging/discharging rates of EVs. The result shows a better performance during grid to vehicle (G2V), at time 20:00 the regulation signal is −650 kW and it fully met by EVs. However, during V2G the performance is quite good, at time 08:00 the regulation signal is 800 kW and EVs meet only 180 kW due to less number of EVs for discharging.

The increasing wind integration in present grids to generate clean energy escalates the problem of low-frequency oscillations (LFOs) in the system. Here, a wide area-based coordinated control strategy of power system stabilisers (PSSs) and doubly fed induction generator's (DFIGs) power oscillation dampers (PODs) is presented to improve the system damping. An improved eigenvalue-based objective function is employed to optimally tune the variables of the controller using whale optimisation algorithm (WOA). The impact of DFIG location and thus the suitable wind farm locations are also found out using eigenvalue analysis and dynamic sensitivity analysis. The results are investigated on IEEE 68 bus test system highlighting the effectiveness of proposed strategy for a wide range of operating scenarios.

This study addresses a demand response programme (DRP) model considering the price elasticity of demand to determine the peak scheduling for different categories of consumers with the possibility of load shifting. The main objective is to minimise daily energy loss and improvement in the node voltage profile of distribution system along with the economic benefits of different stakeholders. The proposed work helps in appropriate selection of DRP for different feeders/consumers. The investigations are performed on a benchmark 33-bus test distribution system and comprehensive analysis is illustrated through simulation results.

This study presents the synergy between the electric vehicle (EV) fast charging station (FCS) and wind generation. A queuing analysis based 24-h FCS charging demand is presented in the study. The uncertainty in wind speed variation is represented with a Weibull distribution function. The impact on the distribution system is analysed for EV penetration up to 50% and wind generation penetration up to 30%. The excess wind energy, reverse power flow, reduction in network losses and voltage deviation are investigated for the IEEE 123 bus radial distribution system to quantify the interaction between FCS and wind generation. The results show that 30% of wind generation is sufficient to supply 50% EV penetration and reduction in active and reactive energy loss is observed by 10.08% and 10.94%, respectively.

Context: The diagnosis of mediastinal lymphadenopathy is always a challenge. There always a need of a technique that is highly accurate as well as safe for diagnosis the same. Aims: The aim of the study is to assess the clinical usefulness and safety profile of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in diagnosing the patients with mediastinal lymphadenopathy. Settings and Design: This was an observational prospective study. Subjects and Methods: One hundred adult patients with mediastinal lymphadenopathy who underwent EBUS-TBNA with aspirate obtained from the most hypoechoic lymph node (with a 22 gauge needle) and its cytopathological analysis were included in the study. Patients were observed for postprocedure complications. Results: Out of 100, 92 cases were reported as adequate (diagnostic yield = 92%). Among these 92, there were 71 granulomatous lymphadenitis (tuberculosis [TB] = 41 [44.5%], sarcoid-like granuloma = 30 [32.2%]). Malignancy was reported in 16 (17.3%) patients, and 5 (5.43%) were reported to have reactive lymphadenopathy. There was one case each of Mycobacterium avium complex and Mycobacterium abscessus. Out of 16 cases of malignancy, six cases were adenocarcinoma, four cases of squamous cell carcinoma, and two cases of small cell carcinoma. There were three cases of Hodgkin's lymphoma and one case of non-Hodgkin's lymphoma. No major complications were noted, except fever (26), nausea (20), mild bleeding (4), bronchospasm (3), and transient intraprocedural hypoxia (2). Conclusions: EBUS-TBNA is highly accurate (diagnostic yield 92%) and safe procedure for diagnosing mediastinal lymphadenopathy. In our experience, granulomatous lymphadenitis was most common with TB as the main etiology.

Background: Liquid-based cytology (LBC) has been developed as an alternative for conventional cytology (CC) in cervical smears. It is now increasingly being used all over the world for cervical cancer screening. However, its role and diagnostic accuracy in bronchial wash (BW)/bronchoalveolar lavage (BAL) specimens remains undetermined. Aims: To assess and compare the diagnostic performance and accuracy of LBC with CC for detecting malignancy in bronchial specimens. Settings and Design: This was a retrospective analytical hospital-based study. Materials and Methods: Bronchial specimens (BW/BAL) received over a period of 4.5 years were reviewed. The samples were processed by CC from June 2010 to September 2012 (2.25 years) and by LBC from October 2012 to December 2014 (2.25 years). Data were retrieved from the records of cytology laboratory and compared among both the groups. Detection rate for histologically or cytologically verified samples was calculated. Results: A total of 559 cases verified by histological and cytological follow-up were evaluated. These included 247 CC cases and 312 LBC cases. The positive diagnostic rate for malignancy in CC was 28.6% whereas that for LBC was 32.9%. The negative diagnostic rates were 66.5% and 66.3% for CC and LBC, respectively. However, unsatisfactory rates had shown a good reduction from 4.4% in CC to 0.6% after LBC introduction. The smears showed more homogeneous distribution of cells with elimination of obscuring factors such as blood, inflammation, and mucus. Conclusions: The diagnostic accuracy of LBC was slightly better than CC. The unsatisfactory rates showed reduction in LBC preparation. Thus, LBC is a viable alternative to CC and has the advantages of standardization of preparation with decrease in unsatisfactory rates.

Introduction: Neurologists in their clinical practice are faced with inquiries about the suitability of stem cell approaches by patients with a variety of acute and chronic (namely neurodegenerative) disorders. The challenge is to provide these patients with accurate information about the scope of stem cell use as well as at the same time, empowering patients with the capacity to make an autonomous decision regarding the use of stem cells. Methods: The Indian Academy of Neurology commissioned an Expert Group Meeting to formulate an advisory to practicing neurologists to counsel patients seeking information and advice about stem cell approaches. Results and Conclusions: In the course of such counselling, it should be emphasized that the information provided by many lay websites might be unsubstantiated. Besides, standard recommendations for the stem cell research, in particular, the application of several layers of oversight should be strictly adhered in order to ensure safety and ethical use of stem cells in neurological disorders.

Background: Metastatic urothelial carcinoma (UC) is rarely described in cytology literature. Appropriate cytological diagnosis is important in certain clinical scenarios to exclude a second primary. Aims: To delineate cytological features that are helpful in diagnosing metastatic UC. Materials and Methods: The study included seven male patients with age range of 48 - 72 years. These patients were diagnosed cases of UC and had now presented with lesions in liver, lungs, bones or lymph nodes. Computed tomographic (CT)/ultrasonographic (USG) guided fine needle aspiration cytology (FNAC) was available from one of these sites. Results: Cercariform cells (CCs) could be identified in five out of seven cases. In four cases, multilayered papillary fragments (MPFs) were identified which were reminiscent of histopathologic appearance of UC. One of these two morphologic features was present in all the cases. However, both CC cells and MPFs were present only in two cases. Conclusion: Previous clinical history is indispensible while diagnosing metastatic UC. MPFs and CC cells are strong morphologic clues to urothelial origin. In poorly differentiated tumors, differentiation from other epithelial tumors may not be possible on the basis of morphology alone.

Tissue diagnosis of small round cell tumors relies heavily on immunohistochemical staining. Two of the small round cell tumors, namely neuroblastoma and primitive neuroectodermal tumor, have considerable morphologic overlap. Many studies suggest that CD99 positivity virtually excludes the diagnosis of neuroblastoma. We report a case of poorly differentiated neuroblastoma in which aberrant CD99 positivity led to diagnostic dilemma.

Ovarian hyperstimulation syndrome (OHSS) is a potentially life-threatening complication, usually iatrogenic after ovulation induction. OHSS is a very rare event in spontaneously conceived pregnancies. Only few cases have been reported in literature to the best of our knowledge. We report a very rare case of spontaneous critical OHSS (according to classification of severity of OHSS as mentioned in Greentop guidelines no. 5, 2006) associated with triplet pregnancy in a 26-year-old woman suffering from severe abdominal pain, distension, and dyspnea. Our case highlights the importance of a strong suspicion for OHSS when a clinical presentation could not be explained by common medical conditions.