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The aim of this study was to investigate the presence of alien phytoplankton species transported through ballast water of ships that docked on the Amazon coast. Phytoplankton samples were collected from 25 ships between 2012 and 2014, revealing 215 identified species, mostly comprising oceanic planktonic marine species. However, several coastal and freshwater species not yet documented on the Maranhão coast were also observed. The identification of several coastal and freshwater species not yet recorded for Amazonian environments in the ballast water of the Ponta da Madeira Maritime Terminal (TMPM), as well as toxic microalgae genera such as the dinoflagellates Alexandrium and Gymnodinium and of some diatom species from the genus Pseudo-nitzchia, raises concerns regarding the possibility of introducing species. This indicates that ballast water can be responsible for the introduction of alien species in Amazonian aquatic environments, thereby highlighting the TMPM as a critical hotspot in the Amazonian region.

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BACKGROUND: Periventricular pediatric low-grade gliomas (pLGG) present a surgical challenge due to their deep-seated location, accessibility, and relationship with the subcortical network connections. Minimally invasive parafascicular approaches with tubular brain retractors (port brain surgery) have emerged, in recent years, as an alternative to conventional microsurgical and endoscopic approaches for removal of periventricular tumors. OBJECTIVES: To describe the minimally invasive approach with tubular brain retractors for periventricular pLGG, its technique, applications, safety, and efficacy. METHODS: In this article, we describe the port brain surgery techniques for periventricular pLGG as performed in different centers, with different commercialized tubular retractor systems. Illustrative cases followed by a literature review are analyzed, with a detailed description of different approaches or techniques, comparing their advantages and disadvantages with contemporary microsurgical and endoscopic approaches. CONCLUSIONS: The port brain surgery with micro-exoscopic vision and endoscopic assistance, for the treatment of deep-seated lesions such as periventricular pLGG, is an alternative for achieving a functionally safe-gross total or subtotal-tumor resection, obtaining adequate tissue for pathological examination. This technique could offer a new dimension for a less-invasive, safe, and effective access to deep-seated tumors, offering the possibility to lower morbidity in experienced hands.

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We present the case of a minimally invasive surgical correction for failed percutaneous atrial septal defect (ASD) closure in a 57-year-old female patient with residual ASD, tricuspid regurgitation, atrial fibrillation, and embolization of one of two occluders to the superior mesenteric artery. Our surgical approach consisted of anterolateral minithoracotomy, aortic and femoral vein cannulation, cryoablation, cardiac device removal, closure of ASD with autologous pericardium, and tricuspid repair. The procedure was uneventful and patient was discharged home on postoperative day 4.

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The significant growth of the cruise ship industry has resulted in economic benefits, but there are also waste management-related challenges. The aim of this case study was to contribute to the research of cruise ship waste management at the Port of Rio de Janeiro. A3 methodology, applied for the first time in this context, was used to create questionnaires to assess the stakeholders involved, revealing that institutional bureaucracy has a negative effect on waste management. In addition, secondary data on unloaded waste, obtained from the transport manifests, showed that 56 % contained reliable information. The main wastes were plastics (57 %), glass (17 %), metal (9 %), and others. With respect to destinations, 41 % were sent to landfills, 55 % recycled and 4 % thermally treated. Only 5 % of cruise ship moorings removed waste at the Port of Rio de Janeiro, attributed to factors such as high costs.

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Objective To describe a tubular retractor technique for brain lesions through a series of cases and to conduct a literature review on intracranial tubular retractors with emphasis on the syringe port system. Materials and Methods We described four cases of lesions with an intraventricular component and different pathological patterns. The surgeries were performed between April, 2021 and July, 2022. The images were acquired through computed tomography (CT) and magnetic resonance imaging (MRI) scans and transferred to the Horos software, version 1.1.7. To make the tubular retractor, a 20-mL syringe and a 14-Fr/Ch, 30-mL/cc Foley probe were used. The syringe was sectioned according to the planned depth based on preoperative imaging. The syringe was the retractor itself, while the probe served as a means of dilating the path to the lesion. Results Gross total resection was achieved in all cases, and the samples collected were satisfactory regarding the results of the anatomopathological study. All patients evolved without any additional deficits and with adequate postoperative image control. Conclusion The syringe as a tubular retractor associated with the Foley probe as a surgical port dilator was useful, and it enabled the radical resection of intracranial tumors related to the lateral ventricle, not limiting the use of auxiliary instruments, neither of microsurgical instruments; therefore, it is an affordable, secure, and inexpensive method.

Objetivo Descrever uma técnica de retração tubular para lesões cerebrais por meio de uma série de casos e realizar uma revisão bibliográfica sobre retratores tubulares intracranianos com ênfase no sistema dilatador-seringa. Materiais e Métodos Foram descritos quatro casos de lesões com componente intraventricular, com diferentes padrões patológicos. As cirurgias foram realizadas entre abril de 2021 e julho de 2022. As imagens foram adquiridas por tomografia computorizada (TC) e ressonância magnética (RM), e transferidas para o programa Horos, versão 1.1.7. Para fabricar o retrator tubular, foram utilizadas uma seringa de 20 mL e uma sonda Foley de 14Fr/Ch, 30mL/cc. A seringa foi seccionada de acordo com a profundidade planejada e com base na imagem pré-operatória. A seringa era o retrator em si, ao passo que a sonda servia como meio de dilatar o caminho para a lesão. Resultados A ressecção total bruta foi alcançada em todos os casos, e as amostras recolhidas foram satisfatórias com relação aos resultados do estudo anatomopatológico. Todos os pacientes evoluíram sem quaisquer déficits adicionais e com controle de imagem pós-operatório adequado. Conclusão A seringa como retrator tubular associado à sonda de Foley como dilatador cirúrgico foi útil e permitiu a ressecção radical de tumores intracranianos relacionados com o ventrículo lateral, e não limitou a utilização de instrumentos auxiliares, nem dos instrumentos microcirúrgicos, sendo assim um método acessível, seguro e pouco dispendioso.

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Objetivo: Determinar la efectividad de la colecistectomía laparoscópica de puerto único asistida por imanes bajo anestesia espinal en el tratamiento quirúrgico de la colecistopatía litiásica crónica. Material y Métodos: Estudio prospectivo de cohorte en 51 pacientes entre octubre de 2019 y febrero de 2021. 17 pacientes fueron sometidos a colecistectomía laparoscópica de puerto único asistida por imanes y 34 a colecistectomía laparoscópica convencional por un mismo equipo quirúrgico. Se aplicó la técnica quirúrgica descrita por Dominguez et al y SAGES, bajo anestesia espinal. Se realizó estadística descriptiva e inferencial, analizando el dolor postoperatorio a las 3, 6, 12, 24 y 72 h y la satisfacción de los pacientes. Resultados: Se encontró diferencia significativa en el dolor postoperatorio en el grupo de estudio a las 6 h (p = 0,022), 12 h (p = 0,039), 24 h (p = 0,025) y 72 h (p < 0,001). En la satisfacción se encuentra un RR de 3 (p = 0,001), sin diferencia significativa en el tiempo operatorio y horas de hospitalización postquirúrgicas. Conclusiones: La colecistectomía laparoscópica de puerto único asistida por imanes, bajo anestesia espinal, ha demostrado efectividad en la reducción importante del dolor postoperatorio a partir de las 6 h, y en la superación de las expectativas en los intervenidos, sin aumento significativo de tiempo operatorio ni estancia hospitalaria.

Aim: To determine the effectiveness of magnet-assisted single-port laparoscopic cholecystectomy under spinal anesthesia in surgical treatment of chronic lithiasic cholecystopathy. Materials and Method: Prospective cohort study in 51 patients between October 2019 and February 2021. 17 patients underwent magnet-assisted single-port laparoscopic cholecystectomy and 34 underwent conventional laparoscopic cholecystectomy by the same surgical team. The surgical technique described by Dominguez and SAGES was used, under spinal anesthesia. Descriptive and inferential statistics were performed, analyzing postoperative pain at 3, 6, 12, 24 and 72 hours and patient satisfaction. Results: A significant difference in postoperative pain was found in the study group at 6 h (p = 0.022), 12 h (p = 0.039), 24 h (p = 0.025) and 72 h (p < 0.001). In satisfaction, there is an RR of 3 (p = 0.001), with no significant difference in operative time and postoperative hospitalization hours. Conclusions: Magnet-assisted single-port laparoscopic cholecystectomy under spinal anesthesia has shown effectiveness in significantly reducing postoperative pain after 6h, associated with significantly exceeding expectations in those operated on, without a significant increase in operative time or hospital stay.

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BACKGROUND: Sleeve gastrectomy is one of the most popular bariatric surgeries. With the advent of new technologies, a reduced-port approach assisted by magnets for sleeve gastrectomy (RPSG-MA) has been developed. The aim of our study is to compare the short-term results of RPSG-MA vs conventional laparoscopic SG (CLSG). METHODS: A comparative study was performed. We compared two groups who underwent RPSG-MA (n=150) and CLSG (n=135) between January 2020 and January 2022. RESULTS: Both groups were similar in body mass index, age, sex, and type of comorbidities. The operative time was similar in both groups (RPSG-MA, 52.5 min vs CLSG, 52.9 min; p = 0.829). Length of hospital (1.07 days) stay was significantly shorter in the RPSG-MA group (p = 0.00) than in the CLSG group (1.51 days). There were no conversions to open surgery in any patient or any fatal event. Complications encountered were similar in both groups postoperative. There were minor adverse events directly related to the magnetic device in 3 cases, these being mild hepatic lacerations, resolved with hemostatic measures. CONCLUSION: The magnet-assisted reduced-port gastric sleeve compared to the conventional technique has proven to be safe, technically feasible and with multiple benefits.

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Port-related activities have a detrimental impact on the air quality both at the point of source and for considerable distances beyond. These activities include, but are not limited to, heavy cargo traffic, onboard, and at-berth emissions. Due to differences in construction, operation, location, and policies at ports, the site-specific air pollution cocktail could result in different human health risks. Thus, monitoring and evaluating such emissions are essential to predict the risk to the community. Environmental agencies often monitor key pollutants (PM2.5, PM10, NO2, SO2), but the volatile organic carbons (VOCs) most often are not, due to its analytical challenging. This study intends to fill that gap and evaluate the VOC emissions caused by activities related to the port of Paranaguá - one of the largest bulk ports in Latin America - by characterizing BTEX concentrations at the port and its surroundings. At seven different sites, passive samplers were used to measure the dispersion of BTEX concentrations throughout the port and around the city at weekly intervals from November 2018 to January 2019. The average and uncertainty of BTEX concentrations (µg m-3) were 0.60 ± 0.43, 5.58 ± 3.80, 3.30 ± 2.41, 4.66 ± 3.67, and 2.82 ± 1.95 for benzene, toluene, ethylbenzene, m- and p-xylene, and o-xylene, respectively. Relationships between toluene and benzene and health risk analysis were used to establish the potential effects of BTEX emissions on the population of the city of Paranaguá. Ratio analysis (T/B, B/T, m,p X/Et, and m,p X/B) indicate that the BTEX levels are mainly from fresh emission sources and that photochemical ageing was at minimum. The cancer risk varied across the sampling trajectory, whereas ethylbenzene represented a moderate cancer risk development for the exposed population in some of the locations. This study provided the necessary baseline data to support policymakers on how to change the circumstances of those currently at risk, putting in place a sustainable operation.

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The aim of the present study was to investigate the effect of dredging activities on the structure of the macrobenthic community of a port complex in São Luís do Maranhão (2°S, Brazil). Sampling was performed on four occasions: pre-dredging, dredging 1 (25% of the material dredged), dredging 2 (75% of the material dredged) and post-dredging. Total mean density was 430.8 ± 55.0 ind/m², with 147.76 ± 280.82 ind/m² at pre-dredging, 161.90 ± 285.67 ind/m² at dredging 1, 53.83 ± 72.15 ind/m² at dredging 2 and 67.29 ± 72.58 ind/m² after dredging, revealing a reduction during dredging 2. The most representative groups were Polychaeta, Oligochaeta, Crustacea and Mollusca. Lumbrineris sp. (Polychaeta) was present in all sampling periods and was the dominant species. Richness and Shannon diversity of the species were higher in the pre-dredging and post-dredging periods, with reductions during the dredging activities (dredging 1 and 2). Principal component analysis revealed a correlation with granulometry and heavy metals in the sediment. The dredging activities led to a reduction in the macrobenthic community. Moreover, post-dredging recovery was insufficient for the recovery of the community.(AU)

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Introducción: En la búsqueda de nuevas y mejores alternativas quirúrgicas que permitan disminuir el trauma a la pared abdominal, ha surgido la cirugía por puerto único (PU), un procedimiento que consiste en la realización de la cirugía laparoscópica a través de una incisión única, generalmente en la cicatriz umbilical. Los resultados han sido alentadores y nuevas investigaciones al respecto son necesarias. Objetivo: Comparar la técnica quirúrgica de la apendicectomía laparoscópica por puerto único (PU) versus técnica estándar de 03 puertos (AL3P) en el tratamiento de pacientes con apendicitis aguda. Metodología: Estudio prospectivo, aleatorizado, incluyó 158 pacientes distribuidos en 2 grupos (71 PU, 89 AL3P), desde junio de 2013 a junio de 2016, comparándose variables demográficas, tiempo quirúrgico, complicaciones trans y postoperatorias, conversión, dolor postoperatorio, beneficios estéticos y satisfacción. Resultados: La edad, sexo, IMC, evolución, medicación previa, recuento leucocitario y fase de la enfermedad fue similar en ambos grupos. El tiempo operatorio promedio en PU fue de 48 min, menor que en AL3P (p˂0,001), y se evidenció disminución del mismo posterior a la curva de aprendizaje de 30 casos. No hubo conversión en PU a cirugía abierta. La tasa de complicaciones intra Y postoperatorias fue similar en ambos grupos (p=0,486 y p=0,887). La estancia hospitalaria fue menor en los pacientes de PU (p˂0,001) con mejor resultado estético (p=0,036) y mayor grado de satisfacción (p=0,047). Conclusión: La apendicectomía por PU demostró ser una técnica factible, segura y reproducible en nuestro medio(AU)

Introduction: In the search for new and better surgical alternatives to reduce the trauma to the abdominal wall, it has emerged single port surgery (SP), a procedure that involves performing laparoscopic surgery through a single incision, usually in the umbilicus. The results have been encouraging and further investigations are needed in this regard. Objective: To compare laparoscopic single port appendectomy (SP) versus standard 03 ports laparoscopic technique (AL3P) in the treatment of patients with acute appendicitis. Materials and Methods: Prospective, randomized study, included 158 patients divided into 2 groups (71 SP, 89 AL3P), from June 2013 to June 2016, comparing demographic variables, surgical time, trans and postoperative complications, conversion, postoperative pain, aesthetic benefits and satisfaction. Results: Age, sex, BMI, evolution, premedication, white blood cell count and stage of the disease was similar in both groups. Mean operative time was 48 min on the SP, lower than in AL3P (p˂0,001), and decreased following the learning curve of 30 cases. There was no conversion of SP to open surgery. The rate of intraoperative and postoperative complications was similar in both groups (p = 0.486 and p = 0.887). The hospital stay was lower in patients SP (p˂0,001), with better cosmetic outcome (p = 0.036) and greater satisfaction (p=0.047). Conclusion: SP appendectomy proved to be a feasible, safe and reproducible technique in our environment(AU)

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The maritime transport of containers between ports accounts for the bulk of global trade by weight and value. Transport impedance among ports through transit times and port infrastructures can, however, impact accessibility, trade performance, and the attractiveness of ports. Assessments of the transit routes between ports based on performance and attractiveness criteria can provide a topological liner shipping network that quantifies the performance profile of ports. Here, we constructed a directed global liner shipping network (GLSN) of the top six liner shipping companies between the ports of Africa, Asia, North/South America, Europe, and Oceania. Network linkages and community groupings were quantified through a container port accessibility evaluation model, which quantified the performance of the port using betweenness centrality, the transport impedance among ports with the transit time, and the performance of ports using the Port Liner Shipping Connectivity Index. The in-degree and out-degree of the GLSN conformed to the power-law distribution, respectively, and their R-square fitting accuracy was greater than 0.96. The community partition illustrated an obvious consistence with the actual trading flow. The accessibility evaluation result showed that the ports in Asia and Europe had a higher accessibility than those of other regions. Most of the top 30 ports with the highest accessibility are Asian (17) and European (10) ports. Singapore, Port Klang, and Rotterdam have the highest accessibility. Our research may be helpful for further studies such as species invasion and the planning of ports.

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PM2.5 samples at Haitian and Songyu container terminals in Xiamen Port were collected in summer and autumn/winter in 2020 and analyzed for 20 elements to investigate their temporal-spatial distribution features, sources, and health risk. The results showed that the levels of PM2.5 were relatively low and did not show significant spatial and diurnal differences. Ca and Si were the main crustal elements, and Zn and Mn were the main heavy metals in PM2.5. Compared with GB 3095-2012 guidelines, Cr(Ⅵ) was in the range of 27.4-28.6 times above the standard. Under the influence of monsoon and port throughput, the concentrations of some elements in summer were higher than those in autumn/winter. Significant diurnal variations were observed for Cu, Zn, SO2, and NO2 but not for V and Ni. Industrial sources were identified as the primary contributor (55.2%-59.4%), followed by traffic (28.7%-31.3%), ship emissions (7.1%-7.7%), and sea salt plus construction dust (4.8%-5.8%). The results of health risk assessment showed that heavy metals in PM2.5in Xiamen Port had potential carcinogenic risk (ECR>1(10-5) to people living near the port, and Cr(Ⅵ), V, and As together accounted for 97.3%-97.5% of the total risks; however, the non-carcinogenic risk was negligible (HI<1), and the major contributors were V, Mn, Ni, and As (89.6%-91.2%). The relative contributions of each contributor to ECR was in the order of traffic (47.2%-49.4%)>industrial (23.8%-24.2%)>ship emissions (16.9%-20.8%)>sea salt plus construction dust (5.7%-12.1%), and the relative contribution to HI was in the order of traffic (38.7%-42.3%)>industrial (24.5%-28.2%)>ship emissions (24.1%-27.2%)>sea salt plus construction dust (5.4%-9.6%).

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Air pollution is a worldwide health problem, and exposure to the pollution can cause damage to the human body, especially to the respiratory and cardiovascular systems. Asthma is the third most common chronic disease in Brazil, presenting high prevalence in some areas. The aim of this study was to evaluate the self-report the prevalence of asthma symptoms in Santos city, Brazil, and its associated factors in the adult population (between 18 and 59 years old). A cross-sectional study was applied in two different areas of the city. The participants of this study were selected by zip code estimated on a random sample. The ECHRS and a demographic questionnaire were used to collect data. Associations between categorical variables were tested using Pearson's chi-square test or Fisher's exact test. Single and multiple logistic regression models were applied to evaluate the risk factors for asthma. Georeferencing was implemented to distribute the cases. The highest prevalence of asthma was found in Ponta da Praia neighborhood (16.4%; p=0.019), as well as waking up with a coughing crisis in the last 12 months (26.4%; p <0.001). The risk factors for asthma were the following: living next Santos Port area (OR: 2.90; 95%CI 1.13-7.44); and the presence of O3 (OR = 2.63; 95%CI 0.86-7.96). This pioneering study demonstrated that living near the port area increases the chances of adults having self-reported asthma symptoms.

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Morphea and facial capillary malformations (port-wine stains) are distinct conditions that can affect the pediatric population. Early localized morphea mimicking a capillary malformation is an uncommon clinical presentation. We present two new cases of girls, aged 2 and 3 years, who presented with erythematous patches, initially diagnosed as capillary malformations, which were later diagnosed as morphea. We also performed a literature review, yielding 12 additional cases that underscore that the unusual presentation of morphea may delay correct diagnosis. Although early management of morphea reduces long-term sequelae, it is important to delay laser treatment for selected acquired vascular malformations, until the diagnosis of morphea is excluded.

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ABSTRACT BACKGROUND: Congenital vascular anomalies and hemangiomas (CVAH) such as infantile hemangiomas, port-wine stains and brain arteriovenous malformations (AVMs) impair patients' lives and may require treatment if complications occur. However, a great variety of treatments for those conditions exist and the best interventions remain under discussion. OBJECTIVE: To summarize Cochrane systematic review (SR) evidence on treatments for CVAH. DESIGN AND SETTING: Review of SRs conducted in the Division of Vascular and Endovascular Surgery of Universidade Federal de São Paulo, Brazil. METHODS: A broad search was conducted on March 9, 2021, in the Cochrane Database of Systematic Reviews to retrieve any Cochrane SRs that assessed treatments for CVAH. The key characteristics and results of all SRs included were summarized and discussed. RESULTS: A total of three SRs fulfilled the inclusion criteria and were presented as a qualitative synthesis. One SR reported a significant clinical reduction of skin redness by at least 20%, with more pain, among 103 participants with port-wine stains. One SR reported that propranolol improved the likelihood of clearance 13 to 16-fold among 312 children with hemangiomas. One SR reported that the relative risk of death or dependence was 2.53 times greater in the intervention arm than with conservative management, among 218 participants with brain AVMs. CONCLUSION: Cochrane reviews suggest that treatment of port-wine stains with pulsed-dye laser improves redness; propranolol remains the best option for infantile hemangiomas; and conservative management seems to be superior to surgical intervention for treating brain AVMs.

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A comprehensive overview of the irreversible port-Hamiltonian system's formulation for finite and infinite dimensional systems defined on 1D spatial domains is provided in a unified manner. The irreversible port-Hamiltonian system formulation shows the extension of classical port-Hamiltonian system formulations to cope with irreversible thermodynamic systems for finite and infinite dimensional systems. This is achieved by including, in an explicit manner, the coupling between irreversible mechanical and thermal phenomena with the thermal domain as an energy-preserving and entropy-increasing operator. Similarly to Hamiltonian systems, this operator is skew-symmetric, guaranteeing energy conservation. To distinguish from Hamiltonian systems, the operator depends on co-state variables and is, hence, a nonlinear-function in the gradient of the total energy. This is what allows encoding the second law as a structural property of irreversible port-Hamiltonian systems. The formalism encompasses coupled thermo-mechanical systems and purely reversible or conservative systems as a particular case. This appears clearly when splitting the state space such that the entropy coordinate is separated from other state variables. Several examples have been used to illustrate the formalism, both for finite and infinite dimensional systems, and a discussion on ongoing and future studies is provided.

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Diabetic retinopathy (DR) is one of the leading causes of blindness worldwide. Multiple treatment options have been used over time to attempt to modify the natural progression of the disease in both proliferative diabetic retinopathy (PDR) and diabetic macular edema (DME). These two retinal complications are the result of microvascular occlusions and vascular hyperpermeability and are considered one of the leading causes of irreversible blindness in patients of working age. It is now well demonstrated that PDR and DME are associated with increased levels of inflammatory and pro-angiogenic factors in the ocular compartment. To date, laser photocoagulation, vascular endothelial growth factor (VEGF) inhibitors, and corticosteroids have demonstrated efficacy in their treatment in large randomized controlled trials and in real-life observational studies. This manuscript aims to provide a comprehensive review of current treatments, including the main drugs used in diabetic pathologic manifestations, as well as new therapeutic alternatives, such as extended-release intraocular devices.

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El tratamiento estándar de la patología vesicular es la colecistectomía laparoscópica, sin embargo, con el pasar del tiempo se ha venido modificando el método convencional haciéndolo cada vez menos invasivo. Objetivo: Demostrar la factibilidad y seguridad de la colecistectomía laparoscópica de dos incisiones (TILC) comparándola con la técnica clásica (CLC) en cuanto a variables tales como tiempo quirúrgico, dolor postoperatorio, estancia hospitalaria, complicaciones y resultado cosmético. Métodos: Se tomó una muestra prospectiva de pacientes y se dividió equitativamente en dos grupos, los que se intervenían por TILC y otros por CLC. Ambos grupos se cuantificaron las variables anteriormente mencionadas y se hizo un análisis estadístico de las mismas tomando como significativo un valor de p < 0.05. Resultados: Existe significancia estadística únicamente cuando se comparaba el dolor postoperatorio medido a las 24 horas del procedimiento y el desenlace estético percibido de manera objetiva por el propio paciente. El resto de las variables no mostraron diferencias importantes entre ambas técnicas. Conclusiones: La colecistectomía laparoscópica por dos incisiones es un procedimiento seguro y factible, comparable en tiempo operatorio, complicaciones y estancia hospitalaria, pero con mejoría del dolor y resultado cosmético del paciente(AU)

The standard treatment for gallbladder pathology is laparoscopic cholecystectomy, however, over time the conventional method has been modified, making it less and less invasive.Objective : The objective of this study is to demonstrate the feasibility and safety of two-incision laparoscopic cholecystectomy (TILC) compared to the classic technique (CLC) in terms of variables such as surgical time, postoperative pain, hospital stay, complications and cosmetic outcome.Methods : A prospective sample of patients was taken and divided equally into two groups, those who underwent TILC and others by CLC. Both groups quantified the variables mentioned above and a statistical analysis was made of them, taking a p value < 0.05 as significant.Results : The result showed that there was statistical significance only when comparing postoperative pain measured 24 hours after the procedure and the aesthetic outcome objectively perceived by the patient himself. The rest of the variables did not show important differences between both techniques.Conclusion : laparoscopic cholecystectomy through two incisions is a safe and feasible procedure, comparable in operative time, complications and hospital stay, but with improvement in pain and cosmetic result of the patient(AU)

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The problem of voltage regulation in unknown constant resistive loads is addressed in this paper from the nonlinear control point of view for second-order DC-DC converters. The converters' topologies analyzed are: (i) buck converter, (ii) boost converter, (iii) buck-boost converter, and (iv) non-inverting buck-boost converter. The averaging modeling method is used to model these converters, representing all these converter topologies with a generalized port-Controlled Hamiltonian (PCH) representation. The PCH representation shows that the second-order DC-DC converters exhibit a general bilinear structure which permits to design of a passivity-based controller with PI actions that ensures the asymptotic stability in the sense of Lyapunov. A linear estimator based on an integral estimator that allows reducing the number of current sensors required in the control implementation stage is used to determine the value of the unknown resistive load. The main advantage of this load estimator is that it ensures exponential convergence to the estimated variable. Numerical simulations and experimental validations show that the PI passivity-based control allows voltage regulation with first-order behavior, while the classical PI controller produces oscillations in the controlled variable, significantly when the load varies.

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The maintenance of port infrastructures presents difficulties due to their location: an aggressive environment or the variability of the waves can cause progressive deterioration. Maritime conditions make inspections difficult and, added to the lack of use of efficient tools for the management of assets, planning maintenance, important to ensure operability throughout the life cycle of port infrastructures, is generally not a priority. In view of these challenges, this research proposes a methodology for the creation of a port infrastructure asset management tool, generated based on the Design Science Research Method (DSRM), in line with Building Information Modeling (BIM) and digitization trends in the infrastructure sector. The proposal provides workflows and recommendations for the survey of port infrastructures from UAVs, the reconstruction of digital models by photogrammetry (due to scarce technical documentation), and the reconstruction of BIM models. Along with this, the bidirectional linking of traditional asset management spreadsheets with BIM models is proposed, by visual programming, allowing easy visualization of the status and maintenance requirements. This methodology was applied to a port infrastructure, where the methodology demonstrated the correct functionality of the asset management tool, which allows a constant up-dating of information regarding the structural state of the elements and the necessary maintenance activities.

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