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In this work, the effect of distilled water, a biodiesel viscosity reducer, and a commercial nonionic surfactant on the apparent permeability of clay-sand cores through the analysis of contact angle, linear swelling, and porous media fluid flow for a northern Mexico crude oil was evaluated. The results showed that the clay content influences the contact angle values having a lower wettability effect in the rocky medium. The addition of biodiesel produces a fluid movement similar to the addition of distilled water. Biodiesel-based flow enhancer not only reduces the crude oil viscosity but also improves the flowability through porous media. However, this behavior is only valid if the soil is not saturated with salty water.

Se desarrolla un modelo matemático para predecir el comportamiento del flujo bifásico a través de un medio fracturado que se analiza como un sistema de placas paralelas irregulares mediante la dimensión fractal perpendicular y longitudinal al flujo. Los resultados predicen un patrón de flujo anular simétrico cuando se inyecta un fluido con mayor afinidad por la pared. Para fluidos con igual afinidad, esto se logra si el fluido menos viscoso se inyecta en la pared. El modelo puede describir la inyección de agua en yacimientos fracturados para incrementar la producción de crudo y, en comparación con otros, permite estimar el gradiente de presión, los perfiles de velocidad y el flujo másico de sistemas bifásicos.

To estimate the impact of hydration interventions on postworkday hydration status and incidence of acute kidney injury (AKI).Thirty agricultural workers were first monitored on a workday without any interventions. On the intervention workday, the same workers were randomized to one of two groups: 169 ounces (oz) (5 L) of plain water (n = 16) or 169 oz (5L) of water with electrolytes (n = 14).No participants in the electrolyte group had an estimate glomerular filtration rate (eGFR) at the end of the workday of less than 90 mL/min/1.73 m2 or met the criteria for AKI in comparison to the water group (eGFR90: 15%; AKI: 23%) or the control group (eGFR90: 28%; AKI: 18%).The study showed that drinking water with electrolytes may lower the risk for development of AKI among agricultural workers.

In this work, we propose a model for the description of the surface morphogenesis of a dispersed system of the solid-solid type. To obtain the model, stochastic formalism based on the master equation and the principles of fractal geometry was applied, so that the surface morphology is characterized by the fractal dimension and the roughness exponent, which are expressed as a function of the composition of the dispersed system and the dynamic parameters associated with surface formation. Theoretical results obtained were compared with experimental results, finding that the variable that shows a significant effect on the morphology of the surface of the solid-solid dispersed system is the specific surface area of the particles of the dispersed phase found in the surface, as predict theoretically.

Bamboo has been identified as a structural element capable of satisfactorily absorbing tension and compression stresses, and, to a lesser proportion, parallel shear along its fibers, as well as bending with possibility of usage in buildings and as viable ecological alternative. The ultrastructure of the bamboo, from the Guadua Velutina species, obtained from the Vega Rica ejido in El Higo, Veracruz, Mexico, was characterized It was characterized the ultra structure of the bamboo, of the species Guadua velutina, obtained of the Ejido Vega Rica of the municipality El Higo, Veracruz, Mexico for use in the industry of the construction. Previously, pieces were tested to determine their mechanical properties: compression and shear parallel to the fiber, following the standards indicated in the methodology. Subsequently, the microscopic analysis of longitudinal and transverse sections of this anisotropic material, with variable porosity in its walls, was carried out. It was found that the arrangement and shape of its fibers that give rise to its porosity is correlated with its resistance to the different stresses to which it is subjected and that its porosity also decreases in joints zones, where its fibers have no defined direction. These findings are important because they make it possible to recognize the durability of the material in such a way that they can be considered in the construction of structural elements.

Objective: During the SARS-CoV-2 pandemic, there has been a significant increase in the prevalence of anxiety and depression. This study sought to establish the probability of migraine progression by comparing data from week 0 with week 12 of quarantine. Methods: A retrospective cohort study. Three hundred ten patients were included, 238 with episodic migraine and 33 with chronic migraine; they all completed a self-administered questionnaire with demographic, clinical, and psychiatric symptom information. A multivariate statistical analysis was conducted to identify factors associated with the progression of migraine. Results: This study demonstrated a 22.5% progression probability from episodic migraine to chronic migraine with an RR 2.7 and CI (1.92–3.95, p < 0.001). The increase in depression scores (p < 0.005), anxiety (p < 0.001), and alteration in sleep quality (p < 0.003) were associated with the worsening of migraine. Conclusion: During the SARS-CoV-2 pandemic, depression, anxiety, and the deterioration of sleep quality influenced the probability of progression from episodic migraine to chronic migraine.

Fluid overload is associated with poor outcomes in patients with acute kidney injury as well as end-stage kidney disease. Lung ultrasound (LUS) has been used in many different settings and specialties including the emergency department, intensive care unit, trauma, cardiology, and nephrology. Although LUS has been a valuable tool in assessing pulmonary congestion, LUS findings may not always be pathognomonic for pulmonary congestion. Furthermore, the feasibility of doing an extensive LUS examination as has been done in research studies may be hard to implement within the clinical setting. This review will go over the use of LUS to evaluate for fluid overload, compare LUS with other markers of fluid overload, review limitations of LUS, and suggest potential future directions in the use of LUS in nephrology.

This review discusses the macrocirculatory and microcirculatory aspects of renal perfusion, as well as novel methods by which to measure renal blood flow. Finally, therapeutic options are briefly discussed, including renal-specific microcirculatory effects.The optimal mean arterial pressure (MAP) needed for preservation of renal function has been debated but is most likely a MAP of 60-80 mmHg. In addition, attention should be paid to renal outflow pressure, typically central venous pressure. Heterogeneity in microcirculation can exist and may be mitigated through appropriate use of vasopressors with unique microcirculatory effects. Excessive catecholamines have been shown to be harmful and should be avoided. Both angiotensin II and vasopressin may improve glomerular flow through a number of mechanisms. Macrocirculatory and microcirculatory blood flow can be measured through a number of bedside ultrasound modalities, sublingual microscopy and urinary oxygen measurement, SUMMARY: Acute kidney injury (AKI) is a common manifestation of organ failure in shock, and avoidance of hemodynamic instability can mitigate this risk. Measurement of renal haemodynamics is not routinely performed but may help to guide therapeutic goals. A thorough understanding of pathophysiology, measurement techniques and therapeutic options may allow for a personalized approach to blood pressure management in patients with septic shock and may ultimately mitigate AKI.

BACKGROUND: Incident rates of ESRD are much higher among black and Hispanic patients than white patients. Access to nephrology care before progression to ESRD is associated with better clinical outcomes among patients with CKD. However, it is unknown whether black or Hispanic patients with CKD experience lower pre-ESRD nephrology consultation rates compared with their white counterparts, or whether such a disparity contributes to worse outcomes among minorities. METHODS: We assembled a retrospective cohort of patients with CKD who received care through the Veterans Health Administration from 2003 to 2015, focusing on individuals with incident CKD stage 4 who had an initial eGFR≥60 ml/min per 1.73 m(2) followed by two consecutive eGFRs