Power system voltage stability analysis and assessment using artificial neural network

Electrical power systems in any part of the world are expected to deliver continuous, uninterrupted and reliable power to the consumers irrespective of the geographical and weather conditions throughout the year. But they are affected by various factors causing problems such as power loss, voltage fluctuation, blackouts, etc. Many modern power systems are regularly facing problems due to voltage instability which is a threat for a reliable and secure operation. The protection of power systems is hugely dependent on the use of the wide range of distance relays based on electromechanical, solid-state and digital electronics technologies. In my study, an Artificial Neural Network (ANN) model is used along with Continuation Power Flow methods to assess the voltage stability of a power system. The Modal Analysis Method is first implemented to identify the most vulnerable load buses of the power system. Hundreds of loading patterns are generated by varying the real and reactive power. With the help of the input patterns and the target outputs, an appropriate ANN is trained and thereafter it is tested with a new set of loading patterns. The proposed method is applied to the IEEE 14 bus test system and the trained ANN provides results for all the vulnerable load buses of the power system.California State University, Northridge. Department of Electrical and Computer Engineering.Includes bibliographical references (pages 15-15

Relationship between Crude Oil Prices and Stock Market: Evidence from India

This paper estimates the linear interdependencies between international crude oil prices and stock market indices of India using weekly data spanning from Jan 2010 to Jan 2017 in a Vector Autoregressive framework. The time series used for the analysis are crude oil futures prices, Nifty Index, and BSE Energy Index. ADF and PP unit root tests reveal that all the time series are non-stationary at level and stationary at first difference. Cointegration test reveals the absence of cointegrating factor i.e. absence of long run relationship. VAR model captures all the time series as endogenous variables and independent variables are studied at two lags. Result shows that the Energy Index is very well explained by the lagged values of Crude oil futures prices, Nifty Index, and BSE Energy Index. Impulse response function reveals that crude oil prices are affected negatively when one standard deviation shocks are given to stock indices. Keywords: Crude oil, BSE Energy Index, Nifty, Vector Autoregression JEL Classifications: Q42, Q4

Rare case of Hirayama’s disease

Hirayama’s disease is a rare benign neurological disorder also known as monomelic amyotrophy, Sobue disease,Juvenile Muscular Atrophy of Distal Upper Extremity (JMADUE). It mainly affects young males in their second or third decades and is most commonly seen in Asian countries like Japan, Malaysia and India. In majority of the cases the cause of the disease is unknown. An 18 year male came with weakness in his right hand and forearm since 1 year. Examination revealed weakness and wasting of muscles of forearm and hand without lower limb involvement and normal deep tendon reflexes. MRI showed focal short segment hyperintense signal in the ventral and right lateral aspect of the cervical cord at C5-C6 level with the involved segment measuring 4x3mm in size. Based on clinical and radiological features a diagnosis of focal amyotrophy was made. Patient is given a cervical collar to prevent flexion at the neck and physiotherapy in the form of hand and forearm exercises were started. Regular follow up of the patient once every 2 months is being done. Hirayama’s disease is a rare, benign, self-limiting neurological disorder. Early diagnosis and management by preventing cervical flexion with the help of a cervical collar has shown to halt the progression of the disease

Stress Distribution and Displacement of Craniofacial Structures Following Force Application in Treatment of an Operated Bilateral Facial Cleft

Objective:The purpose of this study was to analyze the stress distribution and displacement patterns within the craniofacial structures following application of transverse and anteriorly directed forces by means of rapid maxillary expansion and reverse pull headgear, respectively, using a finite element method in a patient with bilateral cleft.Materials and Method:A finite element model was used to determine stress distribution and displacement of various craniofacial structures following application of transverse and anteriorly directed forces.Results:Maximum forward displacement was 8.07 mm at the node corresponding to the incisal edge of the upper central incisor followed by 7.95 mm at the prosthion. Maximum positive displacement lateral displacement was 3.24 mm at the node representing the premolars. The lateral and medial pterygoid plates showed maximum superior movement of about 0.95 mm and 0.79 mm, respectively. In the dentoalveolar region, the stresses were highest in the apical region of the canine. In the maxilla, point A and ANS demonstrated higher stress values compared with previous studies; both inferior and superior surfaces demonstrated high stresses in the range of 10.11 to 10.20 kg/mm2.Conclusion:Although expansion can be achieved in adolescents, displacements are noted more in the structures located anteriorly and along the midline while the posterior and lateral structures demonstrate minimal displacement but high stresses. Rapid maxillary expansion must be used judiciously in adolescents because of its far-reaching effects involving heavy stresses noted at the sphenoid bone, zygomatic bone, nasal bone, and their adjacent sutures

IMMUNOHISTOCHEMICAL EXPRESSION OF CD44 IN COLORECTAL CARCINOMA IN RELATION TO HISTOMORPHOLOGIC PARAMETERS AND CLINICO-PATHOLOGICAL FACTORS: A CROSS-SECTIONAL STUDY.

Background Cancer stem cells (CSC) have proven to play a vital role in cell invasion, metastasis, and treatment resistance in colorectal carcinoma (CRC), which subsequently led to poor outcomes. Cluster of differentiation 44 (CD44) is usually expressed in stem cells in CRCs and can be detected by immunohistochemistry (IHC). Aims The present study aimed to evaluate the role of immunohistochemical expression of CD44 in CRC cases of this region and its relationship with clinicopathological parameters and patient outcomes. Methods A cross-sectional study included 52 patients with primary CRC who were analyzed for CD44 expression by IHC on paraffin-embedded blocks. Data were collected, tabulated, and statistically analyzed by using SPSS Version 23.0. Results The study had a male predominance (70%) with most participants aged above 45 years (82%). Tumors were predominantly left-sided (69%) and larger than 5 cm (73%). CD44 membranous positivity was found in 78.8% of tumor cells and 59.6% of stromal cells. Signet ring cells showed weak CD44 positivity. CD44 expression correlated with higher tumor stages (T3, T4) and larger tumor sizes (>5 cm), but not with nodal stage, perineural, or lymphovascular invasion. Stromal CD44 positivity was found in 59.6% of cases and showed no significant correlation with tumor stage, size, lymphovascular invasion, perineural invasion, or nodal stage (e.g., T stage: T3 - 14 positive, 16 negative; N stage: N0 - 18 positive, 14 negative; tumor size >5 cm - 21 positive, 17 negative). Conclusions CRC prognosis is independently correlated with CD44 expression, a stem cell marker. They are linked to epithelial-mesenchymal transition (EMT) and tumor budding, with increased expression in high-burden instances. Recommendation Further research should be conducted on the role of CD44 expression in colorectal cancer, particularly focusing on post-neoadjuvant chemotherapy cases, to better understand its prognostic implications and potential as a therapeutic target

Complications as indicators of quality assurance after 401 consecutive colorectal cancer resections: the importance of surgeon volume in developing colorectal cancer units in India

<p>Abstract</p> <p>Background</p> <p>The low incidence of colorectal cancer in India, coupled with absence of specialized units, contribute to lack of relevant data arising from the subcontinent. We evaluated the data of the senior author to better define the requirements that would enable development of specialized units in a country where colorectal cancer burden is increasing.</p> <p>Methods</p> <p>We retrospectively analyzed data of 401 consecutive colorectal resections from a prospective database of the senior author. In addition to patient demographics and types of resections, perioperative data like intraoperative blood loss, duration of surgery, complications, re-operation rates and hospital stay were recorded and analyzed.</p> <p>Results</p> <p>The median age was 52 years (10-86 years). 279 were males and 122 were females. The average duration of surgery was 220.32 minutes (range 50 - 480 min). The overall complication rate was 12.2% (49/401) with a 1.2% (5/401) mortality rate. The patients having complications had an increase in their median hospital stay (from 10.5 days to 23.4 days) and the re-operation rate in them was 51%. The major complications were anastomotic leaks (2.5%) and stoma related complications (2.7%).</p> <p>Conclusions</p> <p>This largest ever series from India compares favorably with global standards. In a nation where colorectal cancer is on the rise, it is imperative that high volume centers develop specialized units to train future specialist colorectal surgeons. This would ensure improved quality assurance and delivery of health care even to outreach, low volume centers.</p

Which one is the best-comparison of three treatment modalities in membranous glomerulonephropathy?

Background: This retrospective study explores the efficacy of Modified Ponticelli, Rituximab and Tacrolimus in treating membranous nephropathy, focusing on remission rates. Methods: This retrospective study analyzed 41 membranous nephropathy cases treated with Modified Ponticelli, Rituximab, or Tacrolimus. Statistical analyses included Kruskal-Wallis and Chi-Square tests to evaluate treatment responses, renal markers and remission outcomes, providing comprehensive insights into treatment efficacy. Results: Modified Ponticelli demonstrated substantial reductions in proteinuria (-88.20%) and favorable increases in albumin (15.80%), outperforming Rituximab and Tacrolimus. Significant differences (p=0.0014) in remission outcomes underscore Modified Ponticelli's efficacy, with the highest complete remission rate (26.7%) and notable partial remission rate (73.3%). Rituximab (Complete 0%, Partial 46.2%) and Tacrolimus (Complete 15.4%, Partial 30.8%) exhibited lower rates. Conclusions: In conclusion, Modified Ponticelli demonstrates superior efficacy in achieving both complete and partial remission in membranous nephropathy patients

Unruptured Arteriovenous Malformations of Brain: An overview

Arteriovenous malformations are congenital lesions that occur most commonly in the&nbsp;supratentorial region. These space-occupying vascular lesions consist of multiple arteries and&nbsp;veins, connecting as a fistula without an intervening normal capillary bed. Typically, AVM’s are&nbsp;single lesions, except when associated with hereditary hemorrhagic telangiectasia. The histology&nbsp;includes clusters of normal or dilated arteries and abnormal veins with calcification and&nbsp;occasionally some prior haemorrhage

MOLECULAR HETEROGENEITY IN ACUTE PROMYELOCYTIC LEUKEMIA - A SINGLE CENTRE EXPERIENCE FROM INDIA

Atypical breakpoints and variant APL cases involving alternative chromosomal aberrations are seen in a small subset of acute promyelocytic leukemia (APL) patients. Over 7 different partner genes for RARA have been described. Although rare, these variants prove to be a diagnostic challenge and require combination of advanced cytogenetic and molecular techniques for accurate characterization. Heterogeneity occurs not only at the molecular level but also at clinico-pathological level influencing treatment response and outcome. In this case series we describe the molecular heterogeneity of APL seen in a single tertiary referral centre with a focus on seven variant APL cases from a single tertiary cancer center in India over a period of two and a half years. We discuss five cases with PLZF-RARA fusion and two novel PML-RARA variants, including a Bcr3 variant involving fusion of PML exon4 and RARA exon3 with an additional 40 nucleotides originating from RARA intron2, another involving exon 6 of PML and exon 3 of RARA with addition of 126 nucleotides, which mapped to the central portion of RARA intron 2  To the best of our knowledge this is the first of kind case series from India</jats:p