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Energy that is wasted and lost to the environment is called waste heat. Different heat recovery technologies can be used to recover it. Hot combustion gases from many sources, such as internal combustion engine exhaust, thermal power plants, cement factories, etc., are the primary source of waste heat. A waste heat recovery system is one that uses a heat exchanger to recover energy from high-temperature process outputs and move it to a different area for a useful purpose. This usually results in an increase in the system's thermal efficiency. This lowers the pollution in the environment while simultaneously increasing system efficiency. A thermal energy storage system (TES) is one way to recover energy. TES primarily falls into two categories: sensible heat storage and latent heat storage. The waste heat thermal power fluctuations are the biggest obstacle to energy storage. Energy recovery power systems' functionality and viability from an economic standpoint are severely impacted by these oscillations. Phase change material (PCM) serves as both a heat transfer medium and a fluctuation damping device in this work. The shell and tube heat exchangers were designed using a variety of tube sizes and orientation. The optimal arrangement was simulated to improve melting time and energy storage. To determine the ideal melting time, this study used three aluminum tubes, each with a diameter of 25 mm, at an angle of 60° (internal angle) from one another, and an acrylic shell having internal diameter of 134 mm with wall thickness is of 10 mm. The impact of a thermal energy storage system operating with a variable temperature source was investigated. Both the impact of altering phase angle and amplitude on the PCM melting rate were analyzed. Computational fluid dynamics (CFD) has been used to perform the simulations by varying the amplitude and phase of the user defined function (UDF). It is discovered that the low phase will require a significant amount of time--roughly 56 hours--but that the time required for PCM melting can be slashed to just 108 minutes once the amplitude is raised to 12t (t in seconds). This is good even with temperature variations and having no fins. [ABSTRACT FROM AUTHOR]

Parallel kinematic manipulators have a well advantage over the serial manipulators as a result of their increased stiffness and load carrying capacity. This advantage has increased parallel mechanisms' use in a variety of applications. This article discusses the stiffness analysis of prismatic revolute and spherical (3-PRS) parallel mechanisms in detail. A simple and comprehensive approach is presented to estimate stiffness model of 3-PRS mechanism. 3PRS manipulator has three identical limbs with each limb has prismatic revolute and spherical joint. The proposed 3-PRS mechanism's CAD model is created using Autodesk® inventor professional software. Forward and inverse kinematic model are available. Stiffness models are made analytically as well as the CAD model and analysed using FEA analysis. Analytically and FEA analysis of the CAD model are compared. The results are very close to CAD model, thereby supporting the validity of the presented approach. [ABSTRACT FROM AUTHOR]

Cyber competitions are usually team activities, where team performance not only depends on the members’ abilities but also on team collaboration. This seems intuitive, especially given that team formation is a well-studied discipline in competitive sports and project management, but unfortunately, team performance and team formation strategies are rarely studied in the context of cybersecurity and cyber competitions. Since cyber competitions are becoming more prevalent and organized, this gap becomes an opportunity to formalize the study of team performance in the context of cyber competitions. This work follows a cross-validating two-approach methodology. The first is the computational modeling of cyber competitions using Agent-Based Modeling. Team members are modeled, in NetLogo, as collaborating agents competing over a network in a red team/blue team match. Members’ abilities, team interaction and network properties are parametrized (inputs), and the match score is reported as output. The second approach is grounded in the literature of team performance (not in the context of cyber competitions), where a theoretical framework is built in accordance with the literature. The results of the first approach are used to build a causal inference model using Structural Equation Modeling. Upon comparing the causal inference model to the theoretical model, they showed high resemblance, and this cross-validated both approaches. Two main findings are deduced: first, the body of literature studying teams remains valid and applicable in the context of cyber competitions. Second, coaches and researchers can test new team strategies computationally and achieve precise performance predictions. The targeted gap used methodology and findings which are novel to the study of cyber competitions.

MATERIALS AND METHODS:In this paper, we propose a theoretical model based upon previous studies about personal and social network dynamics of job performance. We provide empirical support for this model using real-world data within the context of the Australian radiology profession. An examination of radiologists' professional network topology through structural-positional and relational dimensions and radiologists' personal characteristics in terms of knowledge, experience and self-esteem is provided. Thirty one breast imaging radiologists completed a purpose designed questionnaire regarding their network characteristics and personal attributes. These radiologists also independently read a test set of 60 mammographic cases: 20 cases with cancer and 40 normal cases. A Jackknife free response operating characteristic (JAFROC) method was used to measure the performance of the radiologists' in detecting breast cancers. RESULTS:Correlational analyses showed that reader performance was positively correlated with the social network variables of degree centrality and effective size, but negatively correlated with constraint and hierarchy. For personal characteristics, the number of mammograms read per year and self-esteem (self-evaluation) positively correlated with reader performance. Hierarchical multiple regression analysis indicated that the combination of number of mammograms read per year and network's effective size, hierarchy and tie strength was the best fitting model, explaining 63.4% of the variance in reader performance. The results from this study indicate the positive relationship between reading high volumes of cases by radiologists and expertise development, but also strongly emphasise the association between effective social/professional interactions and informal knowledge sharing with high performance.

BACKGROUND: The analysis of co-authorship network aims at exploring the impact of network structure on the outcome of scientific collaborations and research publications. However, little is known about what network properties are associated with authors who have increased number of joint publications and are being cited highly. METHODOLOGY/PRINCIPAL FINDINGS: Measures of social network analysis, for example network centrality and tie strength, have been utilized extensively in current co-authorship literature to explore different behavioural patterns of co-authorship networks. Using three SNA measures (i.e., degree centrality, closeness centrality and betweenness centrality), we explore scientific collaboration networks to understand factors influencing performance (i.e., citation count) and formation (tie strength between authors) of such networks. A citation count is the number of times an article is cited by other articles. We use co-authorship dataset of the research field of 'steel structure' for the year 2005 to 2009. To measure the strength of scientific collaboration between two authors, we consider the number of articles co-authored by them. In this study, we examine how citation count of a scientific publication is influenced by different centrality measures of its co-author(s) in a co-authorship network. We further analyze the impact of the network positions of authors on the strength of their scientific collaborations. We use both correlation and regression methods for data analysis leading to statistical validation. We identify that citation count of a research article is positively correlated with the degree centrality and betweenness centrality values of its co-author(s). Also, we reveal that degree centrality and betweenness centrality values of authors in a co-authorship network are positively correlated with the strength of their scientific collaborations. CONCLUSIONS/SIGNIFICANCE: Authors' network positions in co-authorship networks influence the performance (i.e., citation count) and formation (i.e., tie strength) of scientific collaborations.

A number of centrality measures are available to determine the relative importance of a node in a complex network, and betweenness is prominent among them. However, the existing centrality measures are not adequate in network percolation scenarios (such as during infection transmission in a social network of individuals, spreading of computer viruses on computer networks, or transmission of disease over a network of towns) because they do not account for the changing percolation states of individual nodes. We propose a new measure, percolation centrality, that quantifies relative impact of nodes based on their topological connectivity, as well as their percolation states. The measure can be extended to include random walk based definitions, and its computational complexity is shown to be of the same order as that of betweenness centrality. We demonstrate the usage of percolation centrality by applying it to a canonical network as well as simulated and real world scale-free and random networks.

The article discusses Pakistani politics since 1947, focusing on the appointment of Mohammad Ali Jinnah as Governor General of Pakistan in 1974 by Great Britain's King George VI. Other topics discussed include the Indian Independence Act of 1947, oaths of office, and the Government of India Act 1935.

Background: Eosinophilic esophagitis (EoE) is a chronic inflammatory process of the esophagus often associated with structural and motility problems. Previous studies have shown an increased prevalence in males over females, however there is little data exploring the risk of esophageal complications among genders, which may be indicative of differences in disease severity., Methods: This is a retrospective cohort study using National Inpatient Sample data including adults hospitalized between 2016 and 2020 presenting with EoE. The primary outcome measured was inpatient complications related to the patient's history of EoE and secondary outcomes include demographics, comorbidities, month of presentation, and age of patients., Results: Of the 21 755 patients with history of EoE, 112 260 (52%) were male and 10 495 (48%) were female. Males had higher rates of several EoE complications, including esophageal obstruction, food bolus, esophageal rupture, requiring esophageal dilation, requiring esophageal laceration repair with p  < 0.05 for all. Higher rates of females with EoE were seen in the Black population ( p  < 0.05). We also found that males were most likely to have esophageal impaction and esophageal rupture in the month of March ( p  < 0.05). Esophageal impaction was more common in males ages 25-29 ( p  < 0.05), whereas females were more likely from age 75-79 ( p  < 0.05)., Conclusion: Males have an overall high rate of complication from EoE. There was a higher prevalence of females with EoE in the Black population although the rates of complication remained higher in males in this subpopulation. The month of March carries a risk of esophageal impaction and rupture pronounced particularly in men. Age also appears to have an influence on the rate of esophageal impaction., Competing Interests: The authors declare no conflicts of interest., (© 2024 The Author(s). JGH Open published by Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.)

Objective: This study aims to evaluate the viability of a hypothesis for selective targeting of skin cancer cells by exploiting the spectral gap with healthy cells using analytical and numerical simulation., Methods: The spectral gap was first identified using a viscoelastic dynamic model, with the physical and mechanical properties of healthy and cancerous skin cells deduced from previous experimental studies conducted on cell lines. The outcome of the analytical simulation was verified numerically using modal and harmonic analysis. Finally, transient analyses were conducted analytically and numerically to evaluate the difference in vibrational response of healthy and cancerous cells when their resonant frequencies were closely matched. For analysis, we used healthy nucleus diameters of 3 µm, 5 µm and 7 µm, whereas 34 kPa was taken as the stiffness of healthy skin epithelial cells. Based on established trends, the nucleus-to-cytoplasm ratio was utilised to predict physical and mechanical properties as cells undergo neoplastic transformation., Results: Analytical and numerical simulation revealed an approximate frequency difference of 50-100 KHz for the different nucleus diameters. The transient simulation revealed a significant difference in the growth rate of cancer cells' vibration amplitude, which was 10 times greater than that of healthy cells., Conclusions: This study highlights that cancer cells are more prone to resonance with tuned ultrasound frequencies, emphasising the need for detailed dynamic models incorporating the basement membrane's influence and experimental validation., Competing Interests: Conflict of interest The authors declare no competing interests., (Copyright © 2025 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.)

Introduction There is scarce data about the association of metabolic syndrome (MetS) or its components with the development of colonic diverticulosis (CD) in the elderly. We aim to determine the association of MetS and its components with CD in the elderly aged ≥75 years. Methods We conducted a retrospective chart review at St. Luke's University Health Network to identify patients who underwent a colonoscopy between 2011 and 2020. We collected data on patient demographics, comorbidities, and colonoscopy findings. Statistical analyses were conducted to compute means and frequencies of patient characteristics and rates of CD, as well as to test for associations between potential risk factors and the presence of CD.  Results A total of 1239 patients were included with a median age of 80 years, 57.6% females, 89.5% Caucasians, 72.9% with CD, and 66.7% having a left-sided disease. On bivariate analysis, the older age group (p=0.02), Caucasian ethnicity (p=0.01), and hypertension (p=0.04) were found to be significant risk factors for developing CD. Multivariate regression analysis showed older age group and hypertension (OR=1.47, 95% CI: 1.66-2.02, p=0.02) were major risk factors. A significant proportion of patients with left-sided disease had Caucasian ethnicity (p<0.001), while female gender, obesity, and iron deficiency anemia were also seen more frequently, although without statistical significance.  Conclusion In the elderly (>75 years old), our study found hypertension to be associated with an increased risk of CD, while impaired fasting glucose (IFG) was protective. Most patients exhibited isolated left-sided diverticulosis, with pan-diverticulosis associated with higher proportions of adverse health indicators, including American Society of Anesthesiologists (ASA) score ≥3, IFG, hypertriglyceridemia, hypertension, and hypothyroidism. Further research with larger sample sizes in similar age groups is needed to expand upon these findings., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Liaquat et al.)

Focused ultrasound (FUS) is emerging as one of the most promising, non-invasive treatment techniques. The advancement of transducer technology has paved the way for dermatological applications. A comprehensive review is presented for healthcare practitioners and researchers, summarizing the effect of various operational parameters on the injury zone produced by ultrasound beams for various dermatological applications, which include skin tightening, fat reduction, hyperpigmentation and cancer treatment. In this article, we aim to highlight the efficient operational parameters of FUS to enhance pain relief during surgery and its affordability for skin treatment. Finally, a prospective future technique for efficient FUS is discussed., Competing Interests: Conflict of Interest The authors declare no competing interests., (Copyright © 2023 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.)

Pancreatic cancer can be aggressive and commonly metastasizes to various organs. Most commonly, pancreatic cancer metastasizes to the lung, liver, bones, and peritoneum, but very rarely does it spread to the abdominal wall or skeletal muscle. In this case, we discuss a patient who initially presented with weight loss and jaundice from a pancreatic head adenocarcinoma that later metastasized to the rectus abdominis muscle. A 63-year-old female presented with jaundice and weight loss. CT imaging revealed a 2.8 cm pancreatic head mass with pancreatic and biliary ductal dilation. Carbohydrate antigen 19-9 (CA 19-9) level was also found to be elevated to 1810 U/mL. An endoscopic ultrasound-guided biopsy was later performed and confirmed pancreatic adenocarcinoma. The patient underwent a Whipple pancreatoduodenectomy following initial treatment with neoadjuvant FOLFIRINOX chemotherapy. Following the Whipple procedure, she received adjuvant chemotherapy and subsequent imaging revealed no recurrence and decreased CA 19-9 level to 46 U/mL. Eight months afterward, the patient presented once again with lower abdominal pain. Repeat CA 19-9 level was found to have increased to 1503 U/mL. Repeat positron emission tomography scan imaging was performed and showed a 4.7 cm left rectus abdominis muscle mass. The mass was later biopsied, and pathology revealed recurrent, metastatic pancreatic adenocarcinoma. The patient was restarted on chemotherapy with paclitaxel and gemcitabine leading to a reduction in tumor size and CA 19-9 levels of 135 U/mL. However, surgical resection was later pursued due to increased tumor size only four months later. At this time, limited literature is available reporting the occurrence of pancreatic cancer metastasizing to the abdominal wall. Upon literature review, only five cases have been reported to date, and only two of the cases involved the skeletal muscle. Our rare case is the first-time documentation of rectus abdominis metastasis from pancreatic adenocarcinoma arising from the pancreatic head., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Shupp et al.)

Esophageal neuroendocrine carcinoma is very rare and highly aggressive. An 85-year-old man with a history of esophageal squamous cell carcinoma in remission presented 4 years after definitive chemoradiation with new-onset dysphagia. Endoscopy with biopsy revealed high-grade malignancy consistent with neuroendocrine carcinoma. Treatment options were limited to chemotherapy because of his metastatic disease, and he unfortunately died 14 months after diagnosis. The occurrence of esophageal neuroendocrine carcinoma in a site of prior squamous cell carcinoma is very uncommon, and this likely represents a case of radiation-induced malignancy. Therefore, when undergoing radiotherapy, patients and providers should discuss the possibility of this life-threatening complication., (© 2023 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of The American College of Gastroenterology.)

Background OP-29 is a Centers for Medicaid and Medicare Services (CMS) measure to ensure that endoscopists recommend appropriate follow-up intervals after normal colonoscopy in average risk patients. Failure to report OP-29 compliance can adversely affect hospital quality star rating as well as reimbursement for health care. The aim of our quality improvement project was to improve OP-29 compliance to the top decile over three years. Methodology Our sample included patients between 50-75 years of age who received average risk screening colonoscopies with normal findings. We provided intensive education to endoscopists about the importance of OP-29 compliance, developed an Epic Smartlist that directs our endoscopists to list an appropriate reason for colonoscopy intervals other than 10 years, and monitored OP-29 compliance monthly. We became the first health network in the United States to implement the Lumens endoscopy report writing software (Epic Systems Corporation, Verona, USA) and added the OP-29-related Epic Smartlist to the Lumens colonoscopy note template. All statistical analyses were conducted in SPSS version 26 (IBM Corp., Armonk, USA) to compute the means and frequencies of outcomes. Results Our sample included 2,171 patients with a mean age of 60.5 years of whom the majority were female (57.2%) and Caucasians (90%). Our OP-29 score increased from 87.47% to 100% over the course of three years, and this steady improvement was seen broadly across our network. We compared our network score averages to our state and national averages and consistently demonstrated higher compliance rates while reaching the top decile by 2020. Conclusion We believe our improved OP-29 compliance has reduced colonoscopy overutilization, improved health care quality, and reduced health care costs for our patients and health network. To our knowledge, this is the first reported project towards improving OP-29 compliance utilizing the Epic Lumens software. Epic Lumens (Epic Systems Corporation, Verona, USA) added this Smartlist as quick buttons in the standard colonoscopy procedure note templates they built for other organizations to improve health care quality and cost nationally., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Prenatt et al.)

The applications of conventional sensors are limited by the long response time, high cost, large detection limit, low sensitivity, complicated usage and low selectivity. These sensors are nowadays replaced by Nanocomposite-based modalities and nanomaterials which are known for their high selectivity and physical and chemical properties. These nanosensors effectively detect heavy metal contaminants in the environment as the discharge of heavy metals into natural water as a result of human activity has become a global epidemic. Exposure to these toxic metals might induce many health-related complications, including kidney failure, brain injury, immune disorders, muscle paleness, cardiac damage, nervous system impairment and limb paralysis. Therefore, designing and developing novel sensing systems for the detection and recognition of these harmful metals in various environmental matrices, particularly water, is of extremely important. Emerging nanotechnological approaches in the past two decades have played a key role in overcoming environmentally-related problems. Nanomaterial-based fabrication of chemical nanosensors has widely been applied as a powerful analytical tool for sensing heavy metals. Portability, high sensitivity, on-site detection capability, better device performance and selectivity are all advantages of these nanosensors. The detection and selectivity have been improved using molecular recognition probes for selective binding on different nanostructures. This study aims to evaluate the sensing properties of various nanomaterials such as metal-organic frameworks, fluorescent materials, metal-based nanoparticles, carbon-based nanomaterials and quantum dots and graphene-based nanomaterials and quantum dots for heavy metal ions recognition. All these nano-architectures are frequently served as effective fluorescence probes to directly (or by modification with some large or small biomolecules) sense heavy metal ions for improved selectivity. However, efforts are still needed for the simultaneous designing of multiple metal ion-based detection systems, exclusively in colorimetric or optical fluorescence nanosensors for heavy metal cations., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Herein, we describe the successful synthesis of NiWO 4 /Bi 2 S 3 and reduced graphene oxide (rGO-NiWO 4 /Bi 2 S 3 ) nanocomposites through a simple green sol-gel approach. The fabricated composites were subsequently characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy Dispersive X-Ray Analysis (EDX) and ultraviolet-visible spectroscopy (UV-VIS) spectroscopic analyses. Dielectric properties were done by a precision impedance analyzer. Tanδ and dielectric constant for NiWO 4 /Bi 2 S 3 and rGO-NiWO 4 /Bi 2 S 3 were 1.811, 292818, and 0.2970, 344574, respectively, at 20 Hz. The photocatalytic performance of NiWO 4 /Bi 2 S 3 and rGO-NiWO 4 /Bi 2 S 3 was investigated against methylene blue and methyl orange dyes in an aqueous medium. NiWO 4 -Bi 2 S 3 showed degradation of methylene blue 15.52% after 20 min, 21.8% after 30 min and 46.8% after 40 min. Similarly, for methyl orange dye it was 18.1% after 20 min, 54% after 30 min and 59.36% after 40 min. Compared to NiWO 4 /Bi 2 S 3, rGO-NiWO 4 /Bi 2 S 3 exhibited superior degradation efficiency of 7.5% (20 min), 25.24% (30 min) and 57.71% (40 min) for methylene blue, and 35.7% (20 min), 56.98% (30 min) and 72.42% (40 min) for methyl orange under sunlight. This enhancement in photocatalytic and dielectric properties might be attributed to the presence of graphene in rGO-NiWO 4 /Bi 2 S 3 nanococomposite. Different factors such as effect of time, pH, dose of catalyst, concentration of dye were optimized and the reusability of superior catalyst rGO-NiWO 4 /Bi 2 S 3 was also checked for four cycles. In conclusion, promising photocatalytic and dielectric properties of rGO-NiWO 4 /Bi 2 S 3 suggest its potential applications in the photocatalytic degradation of organic pollutants and energy storage materials. This study provides a well-developed route to exploit metal sulphide/oxide nanocomposites in environmental remediation and energy storage devices., (Copyright © 2022 Elsevier Inc. All rights reserved.)

BACKGROUND Synchronous malignancies are primary cancers that are diagnosed in a single individual within a 2-month period. Synchronous malignancies are uncommon, involving only 2.4-8% of all cancer cases, with a very low number of cases of simultaneous gastric and pancreatic cancer. Although cases of synchronous malignancies do exist, synchronous pancreatic adenocarcinoma and signet ring cell (SRC) gastric adenocarcinoma have not been documented. CASE REPORT A 76-year-old woman with a previously diagnosed intraductal papillary mucinous neoplasm (IPMN) presented with left-sided abdominal pain. Initial workup, including computed tomography imaging and endoscopic ultrasound with biopsy, led to the diagnosis of pancreatic adenocarcinoma. Within 1 month of diagnosis, the patient underwent an extended Whipple procedure and was also found to have a primary SRC gastric adenocarcinoma on evaluation of the gastric tissue margins that were removed during the procedure. The patient was initiated on chemoradiation therapy with 5-fluorouracil. However, following a subsequent decline in performance status and multiple hospitalizations, she could not tolerate further cancer treatment and died soon afterwards. CONCLUSIONS Few cases of synchronous malignancies involving the stomach and pancreas have been reported. Because gastric cancer could easily be missed on screening endoscopy; physicians must have a high index of suspicion. In those patients with a prior history of cancer, biopsies should be performed to aid in early diagnosis. To our knowledge, only metachronous cases of SRC gastric and pancreatic adenocarcinoma have been documented. Therefore, this report represents the first case of synchronous SRC gastric adenocarcinoma and IPMN-associated pancreatic adenocarcinoma in the literature.

There is a paucity of studies investigating the impact of chronic corticosteroid use for coexisting conditions in patients with Coronavirus Disease 2019 (COVID-19). Additionally, the information regarding the impact of chronic liver disease (CLD) on COVID-19 outcomes is evolving. Our study aims to investigate hospitalization outcomes of patients with COVID-19 on long term corticosteroids for coexisting conditions while also seeking to compare outcomes between such patients with a history of CLD to analyze the impact on mortality. We conducted a retrospective chart review across our 10-hospital network identifying patients on chronic corticosteroids (Prednisone ≥ 5 mg daily dose or equivalent dose of another steroid, for a duration of 30 days or more) who were hospitalized with COVID-19 from March 1, 2020 to June 30, 2020. Of these patients who met inclusion criteria, patients were then divided into groups based upon their history of CLD. Primary outcomes of the study looked to investigate the hospitalization outcomes of patients with a history of CLD and comorbid conditions requiring chronic corticosteroid use. Secondary outcomes sought to further investigate risk factors for mortality in our study sample. 837 charts were reviewed. 139 patients met inclusion criteria of which 34 patients had a history of CLD. Statistical analysis demonstrated no difference in length of hospital stay but increased ICU admission rate in the CLD group (41.2% vs 23.8%). No statistically significant difference was seen in between the CLD and non-CLD groups in term of complication rates and 28-day mortality. However, chronic corticosteroids patients were found to have higher rates of ICU admission and overall 28-day and ICU mortality in comparison to patients who were not on chronic corticosteroids prior to COVID-19 hospitalization. The larger contributor to COVID-19 severity was likely chronic corticosteroid use rather than CLD and thus chronic corticosteroid use should be limited throughout the COVID-19 pandemic especially in patients with additional speculated risk factors for COVID-19 such as CLD., (© 2021. The Author(s).)

BACKGROUND Plummer-Vinson syndrome is a rare disease that presents with iron-deficiency anemia, dysphagia, and esophageal webs. It usually occurs in middle-aged White women, and it increases the risk for esophageal cancer. The prevalence of Plummer-Vinson syndrome has decreased due to early detection of iron deficiency and repletion of iron stores. Although Plummer-Vinson syndrome has also been commonly described in children and adolescents, it is seldom reported in the elderly population. CASE REPORT An 88-year-old women with a history of mild cognitive impairment, allergic rhinitis, and gastroesophageal reflux disease presented with difficulty in swallowing solid foods. She had a decreased appetite, along with a 4.5-kg weight loss in the last 1 year. She was also found to have severe iron deficiency and mild anemia. Her dysphagia continued to progress even after starting iron supplementation for her iron deficiency. She eventually had a food bolus trapped in her cervical esophagus that required removal via esophagogastroduodenoscopy. A barium swallow revealed a narrowing in the upper esophagus. A repeat esophagogastroduodenoscopy revealed an esophageal web that was dilated, resulting in relief of symptoms. CONCLUSIONS Dysphagia is reported in up to 10% of the elderly population. It commonly causes malnutrition and is associated with increased mortality. The usual etiologies include cognitive dysfunction, neurological disorders, and/or esophageal dysmotility or narrowing. Although the incidence of Plummer-Vinson syndrome has decreased over time, the possibility of its presence should not be overlooked. To our knowledge, the current case is the third case of dysphagia related to Plummer-Vinson syndrome reported in an octogenarian in the literature so far. Iron replacement can help resolve dysphagia in Plummer-Vinson syndrome but dilation of esophageal webs may sometimes be required.

Background Contrast-induced nephropathy (CIN) after primary percutaneous coronary intervention (PCI) is associated with increased mortality and morbidity. The aim of this study is to determine the frequency of CIN after primary PCI and its association with risk factors in patients with ST-segment elevation myocardial infarction (STEMI) at a tertiary care cardiac center in Pakistan. Methodology In this observational study, we included 282 patients who presented with STEMI and underwent primary PCI at the National Institute of Cardiovascular Disease, Karachi, Pakistan, from October 2017 to April 2018. The serum creatinine (mg/dL) levels were obtained at baseline and 48 to 72 hours after the primary PCI procedure, and patients with a 25% increase or ≥ 0.5 mg/dL rise in post-procedure creatinine level (after 48 to 72 hour) were categorized for CIN. Results Out of a total sample of 282 patients, 68.4% (193) were males, and the mean age was 56.4 ± 9.1 years. A majority of the patients, 78.7% (222), were hypertensive and 34% (96) were diabetic. The CIN was observed in 13.1% (37) of the patients, and increased risk of CIN was found to be associated with the presence of diabetes mellitus and increased (>200 mL) use of contrast during the procedure, with odds ratios of 2.3 (1.14-4.63) and 3.12 (1.36-7.17), respectively. Conclusions The CIN after PCI is a common complication associated with the presence of diabetes mellitus and the use of an increased amount of contrast during the procedure., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2020, Kumar et al.)

BACKGROUND There have been few reports of colonic ischemia in patients receiving venovenous extracorporeal membrane oxygenation (VV-ECMO) treatment, and all patients died during the same hospitalization. CASE REPORT A 48-year-old man was admitted with acute respiratory failure secondary to multifocal pneumonia and required VV-ECMO treatment. He developed abdominal distention and colon dilatation and was subsequently found to have ischemic colitis. He was able to recover from critical illness and ischemic colitis with supportive treatment including colonic decompression. CONCLUSIONS Ischemic colitis is associated with mortality in patients receiving ECMO treatment. The understanding of the pathophysiology is still evolving and requires further research to improve patient outcomes.

BACKGROUND Autoimmune pancreatitis (AIP) is a rare, steroid-responsive disease of the pancreas. Concurrent treatment with immunosuppressants, including corticosteroids, increases the risk of developing a severe form of coronavirus disease 2019 (COVID-19) due to infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The World Health Organization (WHO) advises against the use of corticosteroids in patients with SARS-CoV-2 due to their poor outcomes in patients with SARS-CoV and Middle East respiratory syndrome (MERS-CoV), unless these patients require steroid treatment for a coexisting disease. CASE REPORT A 53-year old patient was admitted with symptoms and diagnostic findings consistent with AIP. Thorough etiological workup revealed an elevated IgG4 level of 361 mg/dL and significant clinical response to corticosteroid treatment, leading to a diagnosis of AIP. After finishing steroid treatment at home, the patient was readmitted with another episode of AIP complicated by development of acute necrotic collection and COVID-19 while taking a second course of high dose prednisone. The patient was continued on high dose prednisone, started on azathioprine and intravenous meropenem, and underwent CT guided percutaneous drainage. He also received supportive care for COVID-19. After significant clinical improvement, the patient was discharged to quarantine at home, which he completed uneventfully. CONCLUSIONS Despite the use of corticosteroids due to AIP, this high risk patient recovered from COVID-19 without complications. These findings support the use of corticosteroids when necessary for treatment of coexisting conditions in COVID-19 patients.

Background Patients with mitral stenosis (MS) are more prone to develop left atrial (LA) thrombus. This cross-sectional study was conducted to determine the frequency of LA thrombus on transthoracic echocardiography (TTE) in patients with MS. Methods In this study, we included patients diagnosed with MS undergoing TTE at the echocardiography department of the National Institute of Cardiovascular Disease (NICVD), Karachi, Pakistan. The severity of MS was classified based on the mitral valve area (MVA) as follows: very severe: MVA of ≤1.0 cm 2 ; severe: MVA of ≤1.5 cm 2 ; and mild to moderate: MVA of >1.5 cm 2 . The LA thrombus was observed and noted on TTE. Results A total of 256 MS patients were included in this study, out of which 46.5% (119) were male. The mean age was 33.78 ±11.51 years. MS was classified as mild to moderate in 3.5% of the patients, severe in 54.3%, and very severe in 42.2%. In 98.8% of the patients, the etiology of MS was rheumatic. LA thrombus was observed in 25% (64) of the patients and LA smoke was observed in 12.1% (31). Among other findings, mitral regurgitation (MR) was observed in 17.2% of the patients, aortic regurgitation (AR) in 5.1%, aortic stenosis (AS) in 4.7%, and tricuspid regurgitation (TR) in 48.8%. Five (2%) patients had atrial septal defect (ASD), 17.3% had left ventricular (LV) dysfunction, 15.2% had right ventricular (RV) dysfunction, and vegetation was seen in 11.8% of the patients. Patients with LA thrombus were found to be associated with the following conditions on a higher scale compared to those without: decreased ejection fraction (EF) (52 ±8.5% vs. 54.94 ±6.6%; p: 0.011); RV dysfunction (39.1% vs. 7.3%; p: <0.001); and presence of associated pathologies (82.8% vs. 43.8%; p: <0.001). Conclusion LA thrombus on TTE was detected in a significant number (25%) of patients with MS. It was also found to be strongly associated with the severity of the disease, reduced EF, RV dysfunction, and the presence of associated value pathologies., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2020, Ahmed et al.)

Background and Aim: There is a lack of data on long-term morbidity, particularly dysphagia, following endoscopic variceal band ligation (EVL). The aim of this study are to assess the incidence of dysphagia and variables associated with this complication after EVL., Methods: We identified individuals who completed at least one session of EVL as their sole treatment for varices from August 2012 to December 2017. Included patients achieved "complete eradication" of varices not requiring further therapy. Patients ≥90 days from their last EVL session completed a modified version of the Mayo Clinic Dysphagia Questionnaire. Individuals with dysphagia were invited to undergo a barium esophagram. Patients with pre-EVL dysphagia were excluded., Results: Of the patients, 68 possessed inclusion criteria, nine (13.2%) died and 20 (29.4%) were lost to follow up. For the remaining 39 (57.4%) patients, 23 were males, mean age of 61.7±8.6 years. The most common etiology of liver disease was hepatitis C virus (n=18; 46.2%). The median number of banding sessions was 2.0 (interquartile range [IQR], 1.0-4.0) with a median of 9.0 bands placed (IQR, 3.0-14.0). Twelve patients (30.8%) developed new-onset dysphagia post-EVL. In univariate analysis, pre-EVL MELD score and non-emergent initial banding were associated with long-term dysphagia. In a regression model adjusted for age, sex, number of bands, and use of acid suppression after EVL, no factor was independently associated with dysphagia (all P>0.05). No strictures were identified on subsequent esophageal evaluation., Conclusion: Approximately 30% of patients developed new-onset, chronic dysphagia post-EVL. Incident dysphagia was associated with a non-emergent initial banding session. The mechanism for dysphagia remains unknown.

Background: Inflammatory bowel disease (IBD) can have autoimmunity and/or intestinal barrier dysfunction as part of pathophysiology and may be refractory to all available treatment options. Serum-derived bovine immunoglobulin (SBI) binds microbial components with postulated downstream effects of normalized gut immune and barrier function, which may be useful for managing IBD. The purpose of our study was to evaluate the effectiveness of SBI in the management of refractory IBD, particularly symptoms of chronic diarrhea and loose stools., Methods: We retrospectively analyzed charts for patients diagnosed with IBD (n = 40) who were refractory to standard treatment. Patients received oral SBI 5 g daily for a period of at least 6 weeks. Twelve patients with IBD fulfilled study inclusion criteria. Each patient graded the severity and frequency of gastrointestinal symptoms before starting SBI and at 6 weeks of treatment using a standardized patient assessment form. Means and standard deviations for all symptom scores at baseline and week 6 of treatment were analyzed., Results: Mean symptom scores decreased significantly for nausea (P = 0.02 for severity and P = 0.03 for mean symptom score) and diarrhea (P = 0.0006, P = 0.0001 and P = 0.0001 for severity, frequency and mean symptom score, respectively)., Conclusions: Therapy with SBI alleviated some refractory gastrointestinal symptoms in patients with IBD, including nausea and diarrhea. Increased duration, dosage and/or frequency of SBI might provide additional symptom improvement and could be tested through controlled clinical trials with larger sample sizes and longer follow-up., (Copyright © 2018 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.)

Purpose: Referral access to subspecialty care for patients with gastrointestinal (GI) diseases is not well defined, but has significant importance to patients. We hypothesized that patients experience barriers to care in two common gastroenterology subspecialties, Hepatology and Motility, in a university medical center. Methods: Two hundred thirteen clinic patients (mean age 46.5 years; 66.5% female; 85.6% Caucasians) completed a formatted questionnaire on access to care. Hepatology patients were older (49.7 years, p =0.008); motility patients predominantly female (76.8%, p <0.001). Gender distribution was even for hepatology (51.2% female). Both groups were overweight (mean body mass index 28.4). Results: Patients waited a mean 89.5 days to be seen by a subspecialist. There were differences by subspecialty (107.6 days for motility vs. 64.3 days for hepatology, p =0.022). A larger percentage of motility patients were told nothing was wrong with them (16.8%, p <0.01) and could not be helped (42.1%, p =0.000). Conclusions: Access to care for subspecialty gastroenterology patients in a university center appears to be impacted by a number of variables. While there are similarities, differences exist between these two subspecialties. Motility patients were more likely to have been told they have nothing wrong with them, suffer setbacks financially, and suffer mood problems. Their wait time for appointments was also greater than hepatology patients. Further investigations of referral access for gastroenterology patients may yield additional insights into disease-specific barriers to accessing subspecialty care.

Background & Aims: Series studies have associated increased serum levels of ferritin with liver fibrosis in patients with nonalcoholic fatty liver disease. We aimed to determine the accuracy with which measurements of serum ferritin determine the presence and severity of liver fibrosis, and whether combining noninvasive scoring systems with serum ferritin analysis increases the accuracy of diagnosis of advanced liver fibrosis., Methods: We performed a retrospective analysis of data from 1014 patients with liver biopsy-confirmed nonalcoholic fatty liver disease. Three cut points of serum ferritin level, adjusted for sex, were established based on receiver operating characteristic curve analysis: 1.0-, 1.5-, and 2.0-fold the upper limit of normal. Three multiple logistic regression models were created to determine the association of these cutoff values with liver fibrosis, adjusting for age, sex, race, diabetes, body mass index, and level of alanine aminotransferase., Results: A greater proportion of patients with increased serum levels of ferritin had definitive nonalcoholic steatohepatitis and more-advanced fibrosis than patients without increased levels. In all models, serum level of ferritin was significantly associated with the presence and severity of liver fibrosis. However, for all 3 cutoff values, area under the receiver operating characteristic curve values were low (less than 0.60) for the presence of fibrosis or any stage of liver fibrosis; ferritin level identified patients with fibrosis with 16%-41% sensitivity and 70%-92% specificity. The accuracy with which noninvasive scoring systems identified patients with advanced fibrosis did not change with inclusion of serum ferritin values., Conclusions: Although serum levels of ferritin correlate with more-severe liver fibrosis, based on adjusted multiple logistic regression analysis, serum ferritin levels alone have a low level of diagnostic accuracy for the presence or severity of liver fibrosis in patients with nonalcoholic fatty liver disease., (Copyright © 2014 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Objective: To observe the changes in Doppler waveform of hepatic vein after the administration of terlipressin, and to assess indirectly the efficacy of the drug to reduce the Hepatic Vein Pressure Gradient and portal pressure., Methods: The quasi-experimental study was conducted at the Jinnah Postgraduate Medical Centre, Karachi, from April 1 to November 25, 2011, and comprised 50 patients with cirrhosis with abnormal Doppler waveform of the hepatic vein. Patients with diseases causing abnormal hepatic vein doppler waveform were excluded. Doppler waveforms were studied for 20 minutes before and for 20 minutes after the administration of terlipressin. Tracings with best waveform before and after injection were saved for analysis. Changes in waveform after vasoactive drug were defined as mild, significant, marked and gross changes. SPSS 10 was used for statistical analysis., Results: Of the 50 patients, 36 (72%) were males and 14 (28%) females. Commonest waveform was monophasic 38 (76%). Gross changes i.e. turning triphasic from monophasic waveform was observed in 8 (16%) patients. Significant gross changes were seen in 24 (48%) patients. Total number of patients showing improvement in waveform was 36 (72%). In no case, waveform deteriorated after the administration of terlipressin (p = 0.001)., Conclusion: Non-invasive method of observing the improvement of hepatic vein waveform by duplex ultrasound, after more studies, may be an important tool for assessing and monitoring the effects of portal pressure lowering drugs.

Background: Endoscopic resection of large colorectal lesions is associated with high complication rates., Objective: To evaluate the effect of prophylactic clip closure of polypectomy sites after resection of large (≥2 cm) sessile and flat colorectal lesions., Design: Retrospective study., Setting: Tertiary referral center., Patients and Interventions: Patients with lesions 2 cm or larger who underwent EMR performed by using low-power coagulation current between January 2000 and February 2012. Beginning in June 2006, polypectomy sites were prophylactically closed with clips when possible. Patients had telephone follow-up at 30 days or later to track complications., Main Outcome Measurements: Delayed hemorrhage, postpolypectomy syndrome, and perforation., Results: There were 524 lesions 2 cm or larger in 463 patients, of which 247 (47.1%) were not clipped, 52 (9.9%) were partially clipped, and 225 (42.9%) were fully clipped. There were 31 delayed hemorrhages, 2 perforations, and 6 cases of postpolypectomy syndrome. The delayed hemorrhage rate was 9.7% in the not clipped group versus 1.8% in the fully clipped group. Multivariate analysis showed that not clipping (odds ratio [OR] 6.0; 95% CI, 2.0-18.5), location proximal to the splenic flexure (OR 2.9; 95% CI, 1.05-8.1), and polyp size (OR 1.3; 95% CI, 1.1-1.7 for each 10-mm increase in size) were associated with delayed bleeding., Limitation: Retrospective design., Conclusions: Prophylactic clipping of resection sites after endoscopic removal of large (≥2 cm) colorectal lesions using low-power coagulation current reduced the risk of delayed postpolypectomy hemorrhage. A randomized, prospective trial of clipping large polypectomy sites is warranted., (Copyright © 2013 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.)