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Abstract The Intertropical Convergence Zone (ITCZ) is a narrow tropical belt of deep convective clouds, intense precipitation, and monsoon circulations encircling the Earth. Complex interactions between the ITCZ and local geophysical dynamics result in high climate variability, making weather forecasting and prediction of extreme rainfall or drought events challenging. We unravel the complex spatio-temporal dynamics of the ITCZ and the resulting teleconnection patterns via a novel tropical climate classification achieved using complex network analysis and community detection. We reduce the high-dimensional complex ITCZ dynamics into a simple yet insightful community structure that classifies the tropics into seven regions representing distinct ITCZ dynamics. The two largest communities, encompassing landmasses over the Northern and Southern hemispheres, are associated with coherent seasonal ITCZ dynamics and have significant long-range connections. Temporal analysis of the community structure highlights that the tropical Pacific and Atlantic Oceans communities exhibit substantial variation on multidecadal scales. Further, these communities exhibit incoherent dynamics due to atmosphere-ocean interactions driven by equatorial and coastal oceanic upwelling.

Abstract Multiple sclerosis (MS) is a complex autoimmune disease in which both the roles of genetic susceptibility and environmental/microbial factors have been investigated. More than 200 genetic susceptibility variants have been identified along with the dysbiosis of gut microbiota, both independently have been shown to be associated with MS. We hypothesize that MS patients harboring genetic susceptibility variants along with gut microbiome dysbiosis are at a greater risk of exhibiting the disease. We investigated the genetic risk score for MS in conjunction with gut microbiota in the same cohort of 117 relapsing remitting MS (RRMS) and 26 healthy controls. DNA samples were genotyped using Illumina’s Infinium Immuno array-24 v2 chip followed by calculating genetic risk score and the microbiota was determined by sequencing the V4 hypervariable region of the 16S rRNA gene. We identified two clusters of MS patients, Cluster A and B, both having a higher genetic risk score than the control group. However, the MS cases in cluster B not only had a higher genetic risk score but also showed a distinct gut microbiome than that of cluster A. Interestingly, cluster A which included both healthy control and MS cases had similar gut microbiome composition. This could be due to (i) the non-active state of the disease in that group of MS patients at the time of fecal sample collection and/or (ii) the restoration of the gut microbiome post disease modifying therapy to treat the MS. Our study showed that there seems to be an association between genetic risk score and gut microbiome dysbiosis in triggering the disease in a small cohort of MS patients. The MS Cluster A who have a higher genetic risk score but microbiome profile similar to that of healthy controls could be due to the remitting phase of the disease or due to the effect of disease modifying therapies.

Abstract Background and Aims Initial reports on US COVID-19 showed different outcomes in different races. In this study we use a diverse large cohort of hospitalized COVID-19 patients to determine predictors of mortality. Methods We analyzed data from hospitalized COVID-19 patients (n = 5852) between March 2020- August 2020 from 8 hospitals across the US. Demographics, comorbidities, symptoms and laboratory data were collected. Results The cohort contained 3,662 (61.7%) African Americans (AA), 286 (5%) American Latinx (LAT), 1,407 (23.9%), European Americans (EA), and 93 (1.5%) American Asians (AS). Survivors and non-survivors mean ages in years were 58 and 68 for AA, 58 and 77 for EA, 44 and 61 for LAT, and 51 and 63 for AS. Mortality rates for AA, LAT, EA and AS were 14.8, 7.3, 16.3 and 2.2%. Mortality increased among patients with the following characteristics: age, male gender, New York region, cardiac disease, COPD, diabetes mellitus, hypertension, history of cancer, immunosuppression, elevated lymphocytes, CRP, ferritin, D-Dimer, creatinine, troponin, and procalcitonin. Use of mechanical ventilation (p = 0.001), shortness of breath (SOB) (p

The etiological complexity of multiple sclerosis, an immune-mediated, neurodegenerative disease with multifactorial etiology is still elusive because of an incomplete understanding of the complex synergy between contributing factors such as genetic susceptibility and aberrant immune response. Recently, the disease phenotypes have also been shown to be associated with dysbiosis of the gut microbiome, a dynamic reservoir of billions of microbes, their proteins and metabolites capable of mimicring the autoantigens. Microbial factors could potentially trigger the neuroinflammation and symptoms of MS. In this perspective article, we discussed how microbial molecules resulting from a leaky gut might mimic a host’s autoantigen, potentially contributing to the disease disequilibrium. It further highlights the importance of targeting the gut microbiome for alternate therapeutic options for the treatment of MS.

Abstract. Transgender surgeries are increasingly performed across the globe and in the United States. Although comprehensive centers exist, which are well equipped to cater and tailor to the needs of this population subset, quite often their resultant complications are handled at a different institution owing to the acuity of the condition. However, interestingly the psychosocial needs, medical pathophysiology, available surgical procedures, and their resultant complications are still not a part of the regular medical curriculum. This translates into inadequate care when physicians from vast majority of institutions that do not routinely perform transgender surgery encounter these patients with complications from gender-affirming surgeries. We present a case of a patient who underwent complex multiple gender-affirming surgeries, presenting to our emergency department with an acute abdomen; this resulted in a diagnostic and management dilemma and review of brief pertinent literature. We recommend that transgender medicine and its basics needs should be exposed to currently practicing physicians by continuing medical education, trainees and medical students alike via incorporation into their curriculum, to decrease health disparities among the lesbian, gay, bisexual, transgender, and queer community.

The main aim of the project is to develop a system to charge the electric vehicle battery continuously and to control the three phase grid system. The perturb and observe method is used to get the maximum power from the solar PV array. The electric vehicle battery is connected at bi directional converter at the DC link and the Dc link is also connected at to the voltage source converter, this electric vehicle battery gets charged at low load demand and discharged at high load demand. This converter usually maintains the maximum power at the DC link by this the electric vehicle battery can be charged by taking a low rated battery to store energy of extra power. An adaptive recursive digital filter is used in better way to the maximum results with grid-connected solar PV-Electric vehicle battery system. The system with recursive filter control is controllable when the solar insolation is changing and load demand change. VSC works efficiently without any disturbance under no solar power generation and transfers the reactive power to the grid. The project is done with the help of simulation in MATLAB and test results on a hardware prototype is done through both in steady state conditions and dynamic conditions.

Omental infarction is an uncommon cause of acute abdomen but one that clinically mimics more serious and common causes of acute abdomen like appendicitis and cholecystitis. Historically, it was diagnosed only intraoperatively during surgery for presumed appendicitis or other causes of acute abdomen. But with the increase in the use of imaging, especially abdominal computed tomography (CT) scan in the work-up for acute abdomen, more cases of omental infarction are being diagnosed preoperatively. This has also led to the observation that omental infarction is a self-limiting condition which can be managed conservatively. Currently, conservative management and surgery are the only treatment options for omental infarction with no consensus as to the best treatment modality. Having a patient with both acute appendicitis and omental infarction simultaneously is extremely rare with only two reported cases in the literature thus far. Here, we present a 10-year-old obese female who presented to our hospital with acute abdomen and was found to have acute appendicitis and omental infarction. The patient underwent laparoscopic appendectomy and resection of the infarcted omentum and had uneventful recovery and was discharged on the second postoperative day. In this report, we present a review of current literature on omental infarction and highlight the importance of imaging especially abdominal CT scan in the nonoperative diagnosis and treatment of omental infarction.

Background In Nicaragua, cervical cancer is the leading cause of cancer-related death for women ages 15–44, yet access to the HPV vaccine is limited to those with financial resources to pay for it. Cervical cytology is provided free of charge in public clinics; however, only 10% of women receive Pap smears at the nationally recommended frequency. Previous studies have not investigated how beliefs regarding cervical cancer screening may differ for urban and rural populations in Nicaragua. Furthermore, no investigation has assessed Nicaraguan women’s beliefs about a potential HPV immunization campaign. Given beliefs’ influence on health behavior, we investigated the structural, sociocultural, and knowledge-based factors influencing women’s beliefs regarding cervical cancer screening among urban and rural women in León, Nicaragua, and assessed acceptance of a potential HPV immunization program. Methods Our sequential explanatory mixed-methods study consisted of two phases: (1) a close-ended questionnaire, followed by (2) a qualitative, in-depth interview. Our quantitative sample contained 117 urban and 112 rural participants aged 18–49. We assessed beliefs regarding cervical cancer screening using a 22-item scale, with higher scores indicating screening-promoting beliefs in simple linear and multiple linear regressions. Twenty qualitative interviews, exploring the sociocultural dimensions of knowledge and attitudes indicated by our quantitative findings, were conducted with a sample of 13 urban and 7 rural women aged 19–46. Results The multiple linear regression indicates that greater knowledge of Pap smears, HPV, and cervical cancer is significantly associated with screening-promoting beliefs after adjusting for other relevant factors. There was no significant difference in screening knowledge and beliefs for urban and rural women. Four recurrent themes representing determinants of knowledge, beliefs, and attitudes regarding cervical cancer screening arose from interviews and built on quantitative findings: (1) women’s embarrassment due to the intimate nature of the Pap smear and male gender of exam provider discourages screening; (2) women believe Pap smears and cervical cancer are associated with sexual promiscuity, and this association stigmatizes women with the disease; (3) knowledge of cervical cancer prevention is limited to those who regularly attend health centers; and (4) women find screening inconvenient, believing understaffed clinics increase patient wait time, limit time patients spend with clinicians, and delay Pap results. A fifth theme indicates (5) participants’ acceptance of a potential HPV immunization program. Discussion Future interventions should focus on increasing access to information about cervical cancer prevention for women who do not regularly attend health centers. Furthermore, our results suggest that if funding were allocated to make the HPV vaccine accessible in Nicaragua, it would be well received.

Obesity is becoming a global health burden along with its comorbidities. It imposes tremendous financial burden and health costs worldwide. Surgery has emerged as the definitive treatment option for morbidly obese patients with comorbidities. Laparoscopic sleeve gastrectomy is performed now more than ever making it imperative for physicians and surgeons to recognize both the common and the uncommon risks and complications associated with it. In this report we describe a rare early life-threatening postoperative complication following laparoscopic sleeve gastrectomy. From our extensive review of literature, there is no existing report of acute pancreatitis with splenic infarction postsleeve gastrectomy to this date.

This case describes an intraoperative incidental finding and surgical removal of ectopic liver tissue attached to the gallbladder during a standard laparoscopic cholecystectomy for acute cholecystitis. These anomalies are rare, with interesting associations and possible clinically relevant complications. The details of the case, along with a brief literature review of embryology, common ectopic sites, and associations/complications, are presented in this paper. Since laparoscopic cholecystectomy is a very common procedure, it is important to increase vigilance of ectopic liver tissues during surgeries to minimize complications and provide optimal management.

Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) is a rare clinical condition with only about 100 cases reported in the literature. It is characterized by primary hyperplasia of pulmonary neuroendocrine cells (PNECs) which are specialized epithelial cells located throughout the entire respiratory tract, from the trachea to the terminal airways. DIPNECH appears in various forms that include diffuse proliferation of scattered neuroendocrine cells, small nodules, or a linear proliferation. It is usually seen in middle-aged, nonsmoking women with symptoms of cough, dyspnea, and wheezing. We present a 45-year-old, nonsmoking woman who presented with symptoms of DIPNECH associated with bilateral pulmonary nodules and left hilar adenopathy. Of interest, DIPNECH in our patient was associated with metastatic pulmonary carcinoids, papillary carcinoma of the left breast, oncocytoma and angiomyolipoma of her left kidney, and cortical nodules suggestive of tuberous sclerosis. She had video assisted thoracoscopic surgery (VATS), modified radical mastectomy with reconstruction, and radical nephrectomy. She is currently symptom-free most of the time with over two years of follow-up.

It has been suggested that a cellularly unstable laminar flame, which is freely propagating in unbounded space, can accelerate and evolve into a turbulent flame with the neighbouring flow exhibiting the basic characteristics of turbulence. Famously known as self-turbulization, this conceptual transition in the flow regime, which arises from local interactions between the propagating wrinkled flamefront and the flow, is critical in extreme events such as the deflagration-to-detonation transition (DDT) leading to supernova explosions. Recognizing that such a transition in the flow regime has not been conclusively demonstrated through experiments, in this work, we present experimental measurements of flow characteristics of flame-generated 'turbulence' for expanding cellular laminar flames. The energy spectra of such 'turbulence' at different stages of cellular instability are analysed. A subsequent scaling analysis points out that the observed energy spectra are driven by the fractal topology of the cellularly unstable flamefront.

In this paper, we develop a first principles model that connects respiratory droplet physics with the evolution of a pandemic such as the ongoing Covid-19. The model has two parts. First, we model the growth rate of the infected population based on a reaction mechanism. The advantage of modeling the pandemic using the reaction mechanism is that the rate constants have sound physical interpretation. The infection rate constant is derived using collision rate theory and shown to be a function of the respiratory droplet lifetime. In the second part, we have emulated the respiratory droplets responsible for disease transmission as salt solution droplets and computed their evaporation time, accounting for droplet cooling, heat and mass transfer, and finally, crystallization of the dissolved salt. The model output favourably compares with the experimentally obtained evaporation characteristics of levitated droplets of pure water and salt solution, respectively, ensuring fidelity of the model. The droplet evaporation/desiccation time is, indeed, dependent on ambient temperature and is also a strong function of relative humidity. The multi-scale model thus developed and the firm theoretical underpinning that connects the two scales-macro-scale pandemic dynamics and micro-scale droplet physics-thus could emerge as a powerful tool in elucidating the role of environmental factors on infection spread through respiratory droplets.