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Objective. Laparoscopic cholecystectomy is typically carried out using four ports. The objective of this study was to describe the percutaneous gallbladder traction technique, which allows the number of ports to be reduced, thus optimizing the procedure, with a similar exposure of the surgical site. Materials and methods. 12 pediatric patients with symptomatic cholelithiasis underwent laparoscopic surgery from January 2021 to January 2024. Cholecystectomy was performed using an umbilical port (5 mm, 30-degree scope) and two accessory ports. A laparoscopic loop with a running knot was used to conduct percutaneous gallbladder traction at the right intercostal level. Results. All surgeries were successfully completed. Mean operating time was 90 minutes. Hospital stay was 1-2 days. Postoperative progression was favorable in all patients. Conclusions. These results confirm that cholecystectomy with percutaneous gallbladder traction is safe, cost-effective, and easily reproducible, which means it can be an alternative to the classic technique. [ABSTRACT FROM AUTHOR]

Copyright of Cirugía Pediátrica (English Edition) is the property of Sociedad Espanola de Cirurgia Pediatrica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present work was carried out in the Industrial Center "2 de Diciembre", located in Camagüey, Cuba with the objective of obtaining mathematical models that characterize the thermal loads of the freezing tunnel, depending on the inlet temperature and the quantity of meat. It was observed that there is a direct relationship between the amount of meat to be cooled and the power demanded, that as the input temperature of the meat increases, the power demanded increases, being this value higher for the greater quantity of meat to be stored, as well as that the heat demanded decreases when the inlet temperature of the frozen meat increases. The mathematical models obtained are of great importance for the company since through them it is possible to predict energy consumption for the concept of cooling and freezing the meat, thus predicting the influence of the factors of quantity and temperature of the meat inlet on the energy needs of the company. The NEVERA software was used to obtain the numerical results, while the statistical package Statgraphics® Plus version 5.1 was used for the statistical processing of the data obtained. [ABSTRACT FROM AUTHOR]

Introduction. In pediatrics, there are few standard criteria to classify and consolidate postoperative complications, particularly in appendectomy, where according to the literature, complications range from 5% to 30%. Methods. A cross-sectional, observational, retrospective study of patients undergoing surgery as a result of suspected acute appendicitis (AA) from December 2018 to January 2020 was carried out. Complications were grouped and consolidated according to the Clavien-Dindo (CD) classification. Postoperative complications and factors involved were analyzed by conducting a bivariate and multivariate statistical study using SPSS statistical software, version 25. Results. A total of 124 patients were studied. Mean age was 9 years (3-14 years). 62% were boys, and 38% were girls. All patients underwent appendectomy -- 80.6% through laparotomy, and 19.4% through laparoscopy. 20% of patients had postoperative complications, which were grouped according to the CD classification (p = 0.002). Most complications were included in the CD I group (64%). Collections treated with antibiotic therapy were included in the CD II group (28%). Intra-abdominal collections requiring re-intervention for drainage purposes were included in the CD IIIb group (8%). The main factors driving complications were complicated AA (81% gangrenous and perforated) (p < 0.001) and progression time (80% >24 h of progression) (p = 0.036), which increased mean hospital stay by 7 ± 4 days (p = 0.016). 137 ± 37 CRP levels were associated with plastron identification (p < 0.001), whereas 109 ± 19 CRP levels were associated with peritonitis (p < 0.001). Conclusions. The Clavien-Dindo classification allows post-appendectomy complications in pediatric surgery to be classified using a common language, by associating complication grade with treatment complexity. [ABSTRACT FROM AUTHOR]

Hydrodynamic cavitation is a technology recently implemented for industry applications, such as water treatment, biofuel generation or upgrading of heavy crudes. Heavy crudes are characterised by their low API gravity and high viscosity, which results in higher extraction, transport, and refining costs, and a lower selling price due to their lower content of light fractions such as naphtha. Thus, hydrodynamic cavitation reactors are used to cavitate the crude oil and improve viscosity, and the efficiency is highly dependent on the operating parameters, such as inlet pressure, temperature, and percentage of a hydrogen donor. In this work, the effect of temperature on the fluid dynamics of the crude oil inside the Vortex HCR-Nano reactor is analysed, taking as a response variable the volume fraction of vapour. The CFD study was done using Ansys Fluent, with five different temperatures between 92°F and 350°F, 3D steady-state flow modelling for liquid-vapour multiphase fluid, with realisable k-e turbulence model, and Schnerr-Sauer cavitation. Results show that the volume of vapour increases with temperature, up to a volume of 1.507 cm3, where its main contribution is due to the Vortex effect. Further research includes the behaviour of hydrodynamic cavitation with different crude oils and operating parameters. [ABSTRACT FROM AUTHOR]

Copyright of Ciencia en Desarrollo is the property of Universidad Pedagogica y Tecnologica de Colombia, Centro de Investigaciones y Extension and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Scientia et Technica is the property of Scientia et Technica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Scientia et Technica is the property of Scientia et Technica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Agro Productividad is the property of Colegio de Postgraduados and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The finite element method is one of the most used numerical tools for engineering design. In recent years, novel numerical approximations have been proposed to extend the finite element method to meshes using arbitrary polygons. Such approximations are aimed to improve accuracy and increase the flexibility during the meshing process. However, as any approximation, they exhibit an error that requires to be quantified in order to validate the numerical results. In this paper, we present a technique to estimate the discretization error in energy norm for arbitrary polygonal finite element meshes. This recovery-based technique uses a moving least squares approach that considers constraints to represent the equilibrium equations. We use two benchmark problems to evaluate the effectivity of the error estimator, with good results both locally and globally. [ABSTRACT FROM AUTHOR]

In this work, we performed a finite element analysis (FEA) to characterize the mechanical behavior of the composite pipe Fiberspar in order to investigate the structural integrity of composite pipes for crude oil transport in Colombia. Tests according to ASTM D2290 standard were performed in the laboratory to determine the tensile ultimate strength and compare the results with the numerical model. Failure criteria Tsai-Wu and Tsai-Hill were considered for the pipes working at different pressures, including operational pressure and, thus, the failure values and critical layers were identified. [ABSTRACT FROM AUTHOR]

Copyright of Cirugía Plástica Ibero-Latinoamericana is the property of Cirugia Plastica Ibero-Latinoamericana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In intact microsomes, quercetin 3-O-alpha-(2''-galloyl)rhamnoside (QGR) inhibits glucose-6-phosphatase (G-6-Pase) in a concentration-dependent manner. QGR increased the G-6-Pase K(m) for glucose-6-phosphate without change in the V(max). The flavonol did not change the kinetic parameters of disrupted microsomal G-6-Pase or intact or disrupted microsomal G-6-Pase pyrophosphatase (PPase) activity. This result allowed the conclusion that QGR competitively inhibits the glucose-6-phosphate (G-6-P) transporter (T1) without affecting the catalytic subunit or the phosphate/pyrophosphate transporter (T2) of the G-6-Pase system.QGR strongly inhibits the neoglucogenic capacity of rat liver slices incubated in a Krebs-Ringer bicarbonate buffer, supplemented with lactate and oleate saturated albumin.The QGR G-6-Pase inhibition might explain the decrease in the liver slice neoglucogenic capacity and, in turn, could reduce glucose levels in diabetic patients. [ABSTRACT FROM AUTHOR]

1. At neutral pH, the temperature-dependent release of glutamate-oxaloacetate aminotransferase, glutamate dehydrogenase, malate dehydrogenase and β-hydroxybutyrate dehydrogenase from mitochondria in an in vitro system, is prevented as a function of the concentration of ATP, oxidizable substrates and ADP. On the other hand, orthophosphate causes the release of mitochondrial enzymes (optimum at pH 6.5). Tiffs effect of Pi is completely inhibited by ADP but not by ATP. UTP and UDP partially replace ADP for this activity. The inhibitory effect of ADP is insensitive to either substrate or rutamycin. 2. In absence of added phosphate and at acid pH values (optimum at pH 6.0), ATP or oxidizable substrates cause marked release of latent mitochondrial enzymes. ATP shows magnesium requirement for this activity. Inhibitors of electron transport and phosphoryl transfer reactions completely prevent these effects of ATP and substrates. Inhibitors of mitochondrial alkali metal cation uptake are inactive. Rutamycin and dinitrophenol prevent effects of ATP in freshly prepared but not in aged mitochondria. 3. Chromatographically pure phosphatidylinositol, phosphatidylcholine and phosphatidylethanolamine, but not saturated phospholipids, prevent phosphate from stimulating leakage of latent enzymes from mitochondria. 4. Release of mitochondrial enzymes effected by oxidizable substrates, ATP, ADP and orthophosphate, but not phospholipids, seems to be associated with energy-dependent mitochondrial swelling. 5. It is concluded that the temperature-dependent release of latent enzymes from mitochondria may depend on structural transformations of the mitochondrial membrane controlled in part by the oxidative phosphorylation mechanism. [ABSTRACT FROM AUTHOR]

The study was carried out to determine the in situ DM degradation kinetics of the diet selected by range cattle. Four esophageal cannulated steers (350 ± 5.0 kg BW) were used to obtain extrusa samples during Spring (Apr-Jun), Summer (Jul-Sep), Autumn (Oct- Dec) and Winter (Jan-Mar). To estimate the in situ degradation kinetics, 10g of sample were incubated in the rumen of two fistulated heifers (375 ± 4kg BW) fed alfalfa hay ad lib. The bags were withdrawn from the rumen at 0, 3, 6, 9, 15, 24, 36, 48, 72 and 96h. Data were fitted to the model: Y = a + b (1-e -c*t ), were a is the intercept; b is the slowly degradable fraction; c is the rate constant of disappearance of b; t is the time of incubation and k is the estimated rate of out flow. The potential degradability (PD) was estimated as a + b and the effective degradability (ED) was calculated by: ED= a + (b * c)/(c + k). The parameters a, b, c, PD and ED were analyzed using PROC GLM according to a completely randomized block design. The mean value for fraction (a) was 2O.6% and no differences were registered between seasons (P>0.05). Regarding the fraction (b), no differences were recorded in most parts of the year (Spring, Autumn and Winter) (P>0.05) although higher values (P<0.05) were observed during the rainy months (Summer; 68.0%). Similarly, the constant rate of degradation (c) was 3.5 times higher in Summer (5.7%/h) than in the winter (1.6%/h). Values related to PD were similar between Autumn and Winter (P>0.05), but lower (P<0.05) than those obtained in Spring and Summer. The ED was also different among periods of sampling (P<0.05). Regarding the in situ DM degradability, higher values (P<0.05) were also obtained during the rainy months (24h; 76.1%, and 48h; 83.5%) compared with those obtained when forage in the field is dormant (Winter; 39.1%) and in the dry season (Spring; 62.8%). Results from this study indicate that the constant rate of degradation (c) and the in situ DM degradation at 24 and 48h, may be adequate estimations to identify variations in nutrient availability among diets consumed by range cattle throughout the year. [ABSTRACT FROM AUTHOR]

We investigate the use of Abbe-type refractometers with homogeneous absorbing fluids. We derive a simple model based on electromagnetic optics to describe quantitatively the angular distribution of light around the critical angle and report some experimental tests. First, we verify experimentally that the diffusing film near the base of the prism does in fact deliver light that refracts up to the critical angle. Then we compare experimental profiles of refracted light around the critical angle with theoretical profiles, and find very good agreement. Finally, we use the model to analyze some requirements and limitations on using Abbe-type refractometers on absorbing fluids. [ABSTRACT FROM AUTHOR]

The use of stainless steel in structures has gained momentum in recent years due to its good cost-benefit over time, protection to corrosion, fire resistance and creep resistance greater than that provided by structural steel commonly used in industry. Despite this increase in use there is still some degree of uncertainty and lack of knowledge regarding their application, as steel design codes focus mainly on structural steel. Therefore, the present work reports the results of the numerical study of thin stainless steel beams used in bridges, subjected to concentrated loads, in order to increase the state-of-the art of this particular application. A finite element model is constructed herein taking into account the non-linear behavior of the material and the initial geometric imperfections. This model is validated using experimental data found in the literature. Then, a parametric study on the influence of the thickness ratio (tf/tw) and load area - length of beam ratio (Ss/a) on the ultimate strength is performed. Finally, it is obtained that the use of the stainless steel presents advantages in its post-critical behavior with respect to geometrically similar panels of structural steel, allowing the structural optimization of girders for bridges. [ABSTRACT FROM AUTHOR]

The study was performed to determine the voluntary intake, nutritional value and in vitro gas production of the diet of grazing cattle during two periods of the year: wet (Jul-Dec), and dry (Jan-Jun). Four esophageal cannulated steers (320 ± 5.0 kg BW) were utilized to obtain extrusa samples. The collection was carried out at 700 during 45 min for a period of 4 days during Jul, Sept, Oct, Dec, Jan, Mar, Apr and Jun. The OM voluntary feed intake was determined from total fecal collection and the indigestible fraction of the forage after 48h incubation in the rumen. Chromium sesquoxide (8g/anim/14d) was dosed to the four steers to estimate total fecal production. The sampling was performed morning (700) and evening (1600) for 4 days during the months mentioned above. Estimations of CP, NDF, ADF and lignin were performed. In vitro gas production determinations were carried out by incubating 500 mg DM samples in calibrated 100 ml glass syringes using rumen fluid from two steers fed alfalfa hay ad lib. Gas production was recorded at 0, 3, 6, 15, 24, 36, 48, 72 and 96h. Data were fitted to the exponential equation: Y = a + b (1 - e -c*t). The variables were then analyzed using PROC GLM according to a completely randomized design. Nutritional level was increased (P < 0.05) during the wet season compared with that observed during the dry season. Dry matter intake was increased 82%, CP by 128%, and the gas production rate constant c by 35% during the wet vs. dry season. Potential degradability (a + b) was not affected (P > 0.05). Based on these data a supplementation schedule is warranted during the dry season to improve the body condition score of cattle. Means between rows with different superscritps differ (P<0.05). [ABSTRACT FROM AUTHOR]