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This work presents a study on the absorption capacity of crude contained in aqueous medium, using corncob as absorbent. An experimental design of the generalized factorial type is proposed, taking into account the following factors: particle size, API density of the oil, temperature and salinity of the water; these values emulate a real oil spill. 36 experimental runs are carried out, the percentage of oil absorbed in a sample of corn cob is measured, from a statistical analysis of variance it is possible to determine the factors that have greater and lesser effect on the water absorption process, salinity is a factor that has a greater effect on the absorption process, while the oil quality, measured in API (according to the American Petroleum Institute) has a lesser effect. In addition, the result of an analysis of optimization of conditions and quality of the oils that present the highest percentage of absorption is presented. [ABSTRACT FROM AUTHOR]

Introduction: Multiple adverse effects have been described for the biological therapy in autoimmune diseases including many secondary to immunosuppression producing bacterial, fungal, or viral infections. Clinical case: We present the case of a 64-year-old female patient with proven disseminated cryptococcosis secondary to the use of tofacitinib. Other possible causes of immunosuppression such as the human immunodeficiency virus (HIV) were ruled out. The patient had been in treatment for rheumatoid arthritis diagnosed three years before. This drug is a biological agent that inhibits JAK enzymes. Very few cases of pulmonary and meningeal cryptococcosis in this type of patient have been described in the literature. Conclusion: This case report should be useful for other clinicians to bear in mind the possibility of this type of invasive fungal infection associated with biological therapy and to take a risk-management approach. [ABSTRACT FROM AUTHOR]

An overreactive inflammatory response and coagulopathy are observed in patients with severe form of COVID-19. Since increased levels of D-dimer (DD) are associated with coagulopathy in COVID-19, we explored whether DD contributes to the aberrant cytokine responses. Here we show that treatment of healthy human monocytes with DD induced a dose dependent increase in production of pyrogenic mediator, Prostaglandin E2 (PGE2) and inflammatory cytokines, IL-6 and IL-8. The DD-induced PGE2 and inflammatory cytokines were enhanced significantly by co-treatment with immune complexes (IC) of SARS CoV2 recombinant S protein or of pseudovirus containing SARS CoV-2 S protein (PVCoV2) coated with spike-specific chimeric monoclonal antibody (MAb) containing mouse variable and human Fc regions. The production of PGE2 and cytokines in monocytes activated with DD and ICs was sensitive to the inhibitors of β2 integrin and FcγRIIa, and to the inhibitors of calcium signaling, Mitogen-Activated Protein Kinase (MAPK) pathway, and tyrosine-protein kinase. Importantly, strong increase in PGE2 and in IL-6/IL-8/IL-1β cytokines was observed in monocytes activated with DD in the presence of IC of PVCoV2 coated with plasma from hospitalized COVID-19 patients but not from healthy donors. The IC of PVCoV2 with convalescent plasma induced much lower levels of PGE2 and cytokines compared with plasma from hospitalized COVID-19 patients. PGE2 and IL-6/IL-8 cytokines produced in monocytes activated with plasma-containing IC, correlated well with the levels of spike binding antibodies and not with neutralizing antibody titers. Our study suggests that a combination of high levels of DD and high titers of spike-binding antibodies that can form IC with SARS CoV2 viral particles might accelerate the inflammatory status of lung infiltrating monocytes leading to increased lung pathology in patients with severe form of COVID-19. Author summary: The pathology of severe COVID-19 is associated with massive inflammation and activation of coagulation systems leading to thrombosis and disseminated intravascular coagulation. D-dimer, a degradation product of fibrinogen, accumulates in the blood when thrombus is dissolved. D-dimer is increased following coagulation activation and high levels of D-dimer correlate with poor prognosis in patients with severe disease. Advanced stages of COVID-19 are also associated with high viral loads and presence of Immune Complexes, i. e. viral particles coated with anti-spike protein antibodies. Here we investigated a link between elevated levels of D-dimer, immune complexes, and inflammation in COVID-19 using human monocytes. Our data showed that D-dimer alone induced prostaglandin E2 (PGE2), a final trigger of fever, and inflammatory cytokines, IL-6/IL-8/IL-1β in healthy monocytes. Importantly, PGE2 and cytokines produced by monocytes were significantly increased when monocytes were incubated with D-dimer and immune complexes of SARS CoV-2 viral particles coated with antibodies from COVID-19 patients. These data showed that D-dimer and immune complexes co-amplify the inflammatory responses of monocytes. Understanding the relationship between coagulation cascade and inflammatory response in severe COVID-19 is critical for designing therapies and treatments to improve outcomes of the disease. [ABSTRACT FROM AUTHOR]

"Never, ever be afraid to make some noise and get in good trouble, necessary trouble." - Representative John Lewis It is time now for organized medicine to make "good trouble" and call for racial justice in medical education and health care. It is also time to have an honest confrontation with reality in order to bring about racial healing and become anti-racist organizations. Using a racial justice framework, 4 elements described here can chart our course. Organized medicine must come together in solidarity to make "good trouble" and fight collectively for racial justice so that every community we serve can achieve their full health potential and achieve racial equity-that is, giving people what they need to enjoy full, healthy lives regardless of race. [ABSTRACT FROM AUTHOR]

• Solar field feedback control ensures flux on receiver of central tower solar plant. • 196 PI-controllers and swarm-behavior of groups of heliostats determine aim points. • Controllers tested on a static environment and compared to optimization approach. • Flux on central receiver brought under allowable flux density after 60 iterations. The receiver is one of the critical elements in central tower concentrating solar power plants, which use molten salt as heat transfer fluid. Gradients in the incident flux, a consequence of the natural variability of the solar resource on the earth's surface, and temperature limits must be considered in the operation of the system, due to corrosive phenomena caused by the interaction between the metal alloys used on the receiveŕs tubes and the molten salt. Furthermore, considering thermal stresses in the receiver as operational constraints leads to the prevention of fractures and has the potential to improve the lifespan of the subsystem. In this work, a novel control strategy is tested in a simulated power plant with a nominal thermal power of 450 MW and a solar field with 6482 heliostats. A flux-feedback closed-loop control law is proposed, which manipulates the swarm behavior of groups of aiming points for heliostats in the solar field and also reduces each iteration the information from the incident flux on the receiver's surface into one variable per group. This work established that the proposed controller can reach a steady-state with a configuration of aiming points, which is close to the optimal solution obtained by a hybrid optimization approach, but much faster and with less computational resources. For the simulation and the optimization, a static coupled optical-thermal model is used. [ABSTRACT FROM AUTHOR]

• Increase in D-dimer (DD) is associated with coagulopathy in severe COVID-19. • Immune Complexes (IC) of SARS CoV-2 with human plasma anti-spike IgG were formed. • Monocyte-derived M1 and M2 macrophages activated with DD + IC produce PGE2 and IL-6. • DD + IC activated M2 but not M1 macrophages produce TNFα, IL-1β, and IL-10 cytokines. • DD + IC contribute to inflammatory response in lung macrophages in severe COVID-19. Lung macrophages are the first line of defense against invading respiratory pathogens including SARS-CoV-2, yet activation of macrophage in the lungs can lead to hyperinflammatory immune response seen in severe COVID-19. Here we used human M1 and M2 polarized macrophages as a surrogate model of inflammatory and regulatory macrophages and explored whether immune complexes (IC) containing spike-specific IgG can trigger aberrant cytokine responses in macrophages in the lungs and associated lymph nodes. We show that IC of SARS-CoV-2 recombinant S protein coated with spike-specific monoclonal antibody induced production of Prostaglandin E2 (PGE2) in non-polarized (M0) and in M1 and M2-type polarized human macrophages only in the presence of D-dimer (DD), a fibrinogen degradation product, associated with coagulopathy in COVID-19. Importantly, an increase in PGE2 was also observed in macrophages activated with DD and IC of SARS-CoV-2 pseudovirions coated with plasma from hospitalized COVID-19 patients but not from healthy subjects. Overall, the levels of PGE2 in macrophages activated with DD and IC were as follows: M1≫M2>M0 and correlated with the levels of spike binding antibodies and not with neutralizing antibody titers. All three macrophage subsets produced similar levels of IL-6 following activation with DD+IC, however TNFα, IL-1β, and IL-10 cytokines were produced by M2 macrophages only. Our study suggests that high titers of spike or virion containing IC in the presence of coagulation byproducts (DD) can promote inflammatory response in macrophages in the lungs and associated lymph nodes and contribute to severe COVID-19. [ABSTRACT FROM AUTHOR]

Background: Primary malignant tracheal tumors are rare, accounting for approximately 0.2 % of respiratory tract tumors yearly, with squamous cell carcinomas and adenoid cystic carcinomas accounting for two-thirds of these cases. Sarcomatoid carcinomas are a group of poorly differentiated non-small cell lung carcinomas containing a component of sarcoma or sarcoma-like (spindle and/or giant cell) differentiation, categorized into five morphologic subgroups. Spindle cell sarcomatoid carcinoma is a rare variant of sarcomatoid carcinomas, consisting of only spindle-shaped tumor cells. Only one other case has been reported as a primary tracheal tumor. Case Presentation: We present a 75-year-old male, having progressive dyspnea and cough, with a spindle cell sarcomatoid carcinoma tumor visualized on chest computed tomography scan and confirmed with biopsy. Conclusions: Due to its low incidence, knowledge of treatment methods, prognostic factors, and etiology is limited thus approaches to eradication have widely varied. We are reporting the second published case of spindle cell sarcomatoid carcinoma of the trachea and the first reported successful outcome of definitive treatment with tracheal resection. [ABSTRACT FROM AUTHOR]

Chagas drug discovery has been hampered by a lack of validated assays to establish treatment efficacy in pre-clinical animal models and in patients infected with T. cruzi. Reduced levels of parasite secreted antigens in the blood of infected hosts could be used to demonstrate treatment efficacy. A published proteomic study of parasite secreted antigens identified the hypothetical protein Tc_5171 as a secreted antigen. In this report, we developed Tc_5171 specific antibodies and showed that the native protein was expressed by the three life cycle stages of the parasite. Anti-peptide antibodies were able to detect the parasite antigen in blood of infected mice during the acute and the chronic phase of infection. Benznidazole treatment of infected mice significantly reduced their blood antigen levels. Of clinical significance, patients diagnosed with Chagas disease, either asymptomatic or with cardiac clinical symptoms had significantly higher Tc_5171 antigen levels compared to endemic controls. Pair-wise analysis, before and after Benznidazole treatment, of patients with asymptomatic Chagas disease showed a significant reduction in antigen levels post treatment. Taken together, our results indicate that Tc_5171 could be used as a novel biomarker of Chagas disease for diagnosis and to assess treatment efficacy. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 26-year-old woman with severe right upper quadrant (RUQ) abdominal pain associated with light-colored stool, deep jaundice, dark-colored urine and repeated emesis. She was afebrile but in distress with visible scleral and cutaneous jaundice during physical examination. The article discusses the clinicopathological findings and pathogenesis.

The general objective of this study was to explore responsible leadership as a strength of democratic companies. Through an exploratory analysis to achieve the objective, a sequential design was proposed in 3 structural aspects: a) theories of responsible leadership with old and current literature, b) responsible leadership against social business perspectives, c) main roles of the past and current responsible leadership. The interest in responsible leadership has noticed and gained significant traction in academia, and has become the central theme of modern suspicions in leadership management. In the future, responsible leadership will be fostered in an environment that is key to organizational survival and governance success. The responsible leader must place special emphasis on the highest standards of sustainability and the most advanced technology to minimize the negative impact on the environment and the health and well-being of people. [ABSTRACT FROM AUTHOR]

Solar central receivers have inherently large time constants and time delays caused by their thermal inertia are due to the transport of the heat transfer fluid alongside the panels. This problem is even accentuated if these systems are continuously exposed to direct normal irradiance (DNI) fluctuations. Ensuring an adequate operation of this kind of process implies the adaptation of control strategies. This paper proposes a strategy that couples the temperature control of the outlet fluid while considering the heliostats' aiming points location to maintain the receiver operating below its design limit and simulates its performance under several scenarios. These tests are carried out on a non-steady-state solar plant model that considers its optical and thermal characteristics. The structure of the proposed control system is based on using intermediate flow valves along the heating flow path to reduce time delay. Hence, it renders the control system more responsive to either a DNI variation affecting the solar field or moving its operation from one state to another. The control strategy structure contains feedback and feedforward loops to determine the near-future process response to DNI measurements. It allows adding more information to the loop used to maintain the system's desired steady-state operation. The overall strategy can take the process to a steady-state operation regardless of the hour or day of operation. It produces a low variation of the outlet temperature, with a standard deviation of 3 °C, while the receiver is under a transient DNI and maintains the heliostats aimed toward the receiver without exceeding its heat flux limits. Results indicate that the proposed strategy achieves over 80% improvement based on the integral absolute error (IAE) performance index compared to conventional single-loop temperature control. Besides the simulated numerical results, this research also presents the advantages of considering intermediate mass-flow valves for control purposes of the receiver. This work should be considered a step towards improving multivariable control algorithms for the safe operation of solar central receivers. [ABSTRACT FROM AUTHOR]

The performance of solar central receivers is inherently linked to the aiming distribution/cluster of heliostats over the surface of solar receivers. A reliable methodology is necessary to maintain the lifespan of these costly devices. This research presents a method for manipulating the heliostats' aiming within a solar field by using a group behavior that relies on a single manipulated variable. This methodology addresses the problem by accounting for the heliostat position over the field, and a reduced number of the required groups. The work relies on the adaptation of an ordinary differential equation, commonly used to model conventional control valves, to establish the mean movement of the heliostats' aiming within the group. Afterward, these values are coupled to predefined paths that set the direction of motion for each point. It is shown that the proposed approach can promote changes in the heat flux profiles on the receiver, thereby allowing for the reduction of the peak heat fluxes about 30% of the initial value, while maintaining spillage below 15% for a spread aiming point distribution. Image 1 • Large groups of heliostats can work harmonized using a single primary signal. • The behavior of the group adopts the working principle of a control valve. • It enables the implementation of a vast amount of closed-loop control strategies. • New strategies allow better distribution of solar radiation over central receivers. • Reduction of heat flux peaks to 30% of the initial value with spillages below 15%. [ABSTRACT FROM AUTHOR]

Borrelia burgdorferi (Bb) sensu lato, the etiologic agent of Lyme borreliosis, adapts to distinct environments in the mammalian host and the tick vector by differential gene expression. As a result, infected mice are not exposed to and rarely make antibodies to the set of antigens that are preferentially expressed in the tick, including outer surface protein A (OspA), Borrelia iron and copper-binding protein A (BicA), and OspD. Surprisingly, however, antibodies to OspA and BicA have been noted in American patients with Lyme arthritis. Here, we examined serum samples from 210 American patients and 66 European patients with a range of early or late manifestations of Lyme borreliosis and found that only American patients with Lyme arthritis commonly had antibody responses to OspA, BicA, and OspD. This suggests that infection with American but not European Borrelia strains often leads to concerted upregulation or derepression of tick-specific spirochetal antigens in these patients. [ABSTRACT FROM PUBLISHER]

Background: Magnetic resonance imaging (MRI) studies have shown decreased caudate volumes in individuals with attention deficit hyperactivity disorder (ADHD). However, most of these studies have been carried out in male children. Very little research has been done in adults, and the results obtained in children are difficult to extrapolate to adults. We sought to compare the volume of the caudate of adults with ADHD with that of healthy controls; we also compared these volumes between men and women. Methods: We performed an MRI scan on 20 adults with ADHD (10 men and 10 women) aged 25-35 years and 20 healthy controls matched by age and sex. We used voxel-based morphometry with the DARTEL algorithm for image analyses. We used the specifically designed Friederichsen, Almeida, Serrano, Cortes Test (FASCT) to measure the severity of ADHD; both the self-reported (FASCT-SR) and the observer (FASCT-O) versions were used. Results: The statistical parametric map showed a smaller region with low grey matter volume and a smaller concentration of grey matter in this region of the right caudate in ADHD patients than in health controls, both in the entire sample and within each sex. There was a significant correlation between the volume of this region of the caudate with the number of DSM IV-TR criteria, as well as with the total scores and most of the factors of the FASCT-SR and FASCT-O scales. A separate correlation analysis by sex gave similar results. Limitations: The study design was cross-sectional. Conclusion: The region of the right caudate with low grey matter volume was smaller in adults with ADHD in both sexes and was correlated with ADHD severity. [ABSTRACT FROM AUTHOR]