Aplicación del método de Montecarlo para la validación del presupuesto de un buque tipo Suezmax

As the name suggests, the budget for the construction of a ship, in this case a Suezmax, means to specifically pre-suppose in economic terms, the activities and movements to carry out during the construction of said ship. The importance of this essential phase of the construction process lie one hand in budgeting a competitive price in the market, but without causing economic losses for the shipyard, in order to make a profit for the company.  This study proposes the use of the Monte Carlo method to obtain a greater reliability in the valuation of the Suezmax vessel; in this case, the triangular method will be used, which starting point is based on results obtained from previous research and from which the most likely, most pessimistic and most optimistic ship budget is obtained in order to later perform a simulation. For the realization of said simulation the ship is divided into different items, that will be assigned an optimistic and pessimist percentage based on a likely budget, according to the degree of trust of the shipyard in said concept.The final scope will be the calculation of the management reserve used to rectify any unforeseen item(s) in the construction of the ship.Tal y como dice su nombre, el presupuesto de un buque, en este caso un Suezmax, es justamente pre-suponer en materia económica, las actividades y movimientos a realizar durante la construcción de dicho buque. La importancia de esta fase esencial del proceso de construcción radica por un lado en presupuestar un precio competitivo en el mercado, pero sin que llegue a causar pérdidas económicas para el astillero, de manera que se busque un beneficio para la empresa. En este estudio se utilizará el método de Montecarlo para conseguir mayor fiabilidad en la tasación del buque Suezmax; en este caso, se empleará el método triangular cuyo punto de partida se basa en resultados obtenidos en investigaciones anteriores y del que se obtiene el presupuesto del buque más probable, el más pesimista y el más optimista para posteriormente realizar una simulación. Para la realización de dicha simulación se divide el buque en diferentes ítems, a los que se les asignará un porcentaje optimista y pesimista determinado en base a un presupuesto probable, según el grado de confianza del astillero en dicho concepto. El alcance final será el cálculo de la reserva de gestión que se emplea para subsanar cualquier imprevisto en la construcción del buque

The Quasi-Verbal Dispute Between Kripke and 'Frege-Russell'

Traditional descriptivism and Kripkean causalism are standardly interpreted as rival theories on a single topic. I argue that there is no such shared topic, i.e. that there is no question that they can be interpreted as giving rival answers to. The only way to make sense of the commitment to epistemic transparency that characterizes traditional descriptivism is to interpret Russell and Frege as proposing rival accounts of how to characterize a subject’s beliefs about what names refer to. My argument relies on a development of the distinction between speaker’s reference and semantic reference

Goodbye Hartmann trial: a prospective, international, multicenter, observational study on the current use of a surgical procedure developed a century ago

Background: Literature suggests colonic resection and primary anastomosis (RPA) instead of Hartmann's procedure (HP) for the treatment of left-sided colonic emergencies. We aim to evaluate the surgical options globally used to treat patients with acute left-sided colonic emergencies and the factors that leading to the choice of treatment, comparing HP and RPA. Methods: This is a prospective, international, multicenter, observational study registered on ClinicalTrials.gov. A total 1215 patients with left-sided colonic emergencies who required surgery were included from 204 centers during the period of March 1, 2020, to May 31, 2020. with a 1-year follow-up. Results: 564 patients (43.1%) were females. The mean age was 65.9 ± 15.6 years. HP was performed in 697 (57.3%) patients and RPA in 384 (31.6%) cases. Complicated acute diverticulitis was the most common cause of left-sided colonic emergencies (40.2%), followed by colorectal malignancy (36.6%). Severe complications (Clavien-Dindo ≥ 3b) were higher in the HP group (P < 0.001). 30-day mortality was higher in HP patients (13.7%), especially in case of bowel perforation and diffused peritonitis. 1-year follow-up showed no differences on ostomy reversal rate between HP and RPA. (P = 0.127). A backward likelihood logistic regression model showed that RPA was preferred in younger patients, having low ASA score (≤ 3), in case of large bowel obstruction, absence of colonic ischemia, longer time from admission to surgery, operating early at the day working hours, by a surgeon who performed more than 50 colorectal resections. Conclusions: After 100 years since the first Hartmann's procedure, HP remains the most common treatment for left-sided colorectal emergencies. Treatment's choice depends on patient characteristics, the time of surgery and the experience of the surgeon. RPA should be considered as the gold standard for surgery, with HP being an exception

Infected pancreatic necrosis: outcomes and clinical predictors of mortality. A post hoc analysis of the MANCTRA-1 international study

: The identification of high-risk patients in the early stages of infected pancreatic necrosis (IPN) is critical, because it could help the clinicians to adopt more effective management strategies. We conducted a post hoc analysis of the MANCTRA-1 international study to assess the association between clinical risk factors and mortality among adult patients with IPN. Univariable and multivariable logistic regression models were used to identify prognostic factors of mortality. We identified 247 consecutive patients with IPN hospitalised between January 2019 and December 2020. History of uncontrolled arterial hypertension (p = 0.032; 95% CI 1.135-15.882; aOR 4.245), qSOFA (p = 0.005; 95% CI 1.359-5.879; aOR 2.828), renal failure (p = 0.022; 95% CI 1.138-5.442; aOR 2.489), and haemodynamic failure (p = 0.018; 95% CI 1.184-5.978; aOR 2.661), were identified as independent predictors of mortality in IPN patients. Cholangitis (p = 0.003; 95% CI 1.598-9.930; aOR 3.983), abdominal compartment syndrome (p = 0.032; 95% CI 1.090-6.967; aOR 2.735), and gastrointestinal/intra-abdominal bleeding (p = 0.009; 95% CI 1.286-5.712; aOR 2.710) were independently associated with the risk of mortality. Upfront open surgical necrosectomy was strongly associated with the risk of mortality (p < 0.001; 95% CI 1.912-7.442; aOR 3.772), whereas endoscopic drainage of pancreatic necrosis (p = 0.018; 95% CI 0.138-0.834; aOR 0.339) and enteral nutrition (p = 0.003; 95% CI 0.143-0.716; aOR 0.320) were found as protective factors. Organ failure, acute cholangitis, and upfront open surgical necrosectomy were the most significant predictors of mortality. Our study confirmed that, even in a subgroup of particularly ill patients such as those with IPN, upfront open surgery should be avoided as much as possible. Study protocol registered in ClinicalTrials.Gov (I.D. Number NCT04747990)

Exclusive self-assembly of a polar dimeric capsule between tetraurea calix[4]pyrrole and tetraurea calix[4]arene

The exclusive self-sorting observed in the self-assembly process between tetraurea benzyl calix[4]pyrroles and tetraurea tolyl calix[4]arene to afford unprecedented hybrid dimeric capsules with polar interiors is described. The coencapsulation of a solvent molecule with an organic guest yields four particle aggregates in which the guests are confined and restricted into single hemispheres due to the polar requirements of the internal cavity

An Optimization Model To Incorporate CO₂ Emissions in the Scheduling of Crude Oil Operations

In previous works CO₂ emissions in oil refineries have been studied for production unit planning. In this manuscript the associated CO₂ mitigation costs are added to the scheduling of crude oil unloading and blending. Numerical simulations executed on literature cases show that the optimal scheduling may be affected, and thus CO₂ emissions may be greater than those predicted from production unit planning. Furthermore, the biobjective problem of maximizing profits and minimizing CO₂ emissions is studied; pareto-optimal solutions and the lowest carbon pricing that induces the refinery to minimize CO₂ emissions are presented for each case

Thermodynamic Characterization of Halide−π Interactions in Solution Using “Two-Wall” Aryl Extended Calix[4]pyrroles as Model System

Herein, we report our latest experimental investigations of halide−π interactions in solution. We base this research on the thermodynamic characterization of a series of 1:1 complexes formed between halides (Cl^–, Br^–, and I^–) and several α,α-isomers of “two-wall” calix[4]­pyrrole receptors bearing two six-membered aromatic rings in opposed <i>meso</i> positions. The installed aromatic systems feature a broad range of electron density as indicated by the calculated values for their electrostatic surface potentials at the center of the rings. We show that a correlation exists between the electronic nature of the aromatic walls and the thermodynamic stability of the X^–⊂receptor complexes. We give evidence for the existence of both repulsive and attractive interactions between π systems and halide anions in solution (between 1 and −1 kcal/mol). We dissect the measured free energies of binding for chloride and bromide with the receptor series into their enthalpic and entropic thermodynamic quantities. In acetonitrile solution, the binding enthalpy values remain almost constant throughout the receptor series, and the differences in free energies are provoked exclusively by changes in the entropic term of the binding processes. Most likely, this unexpected behavior is owed to strong solvation effects that make up important components of the measured magnitudes for the enthalpies and entropies of binding. The use of chloroform, a much less polar solvent, limits the impact of solvation effects revealing the expected existence of a parallel trend between free energies and enthalpies of binding. This result indicates that halide−π interactions in organic solvents are mainly driven by enthalpy. However, the typical paradigm of enthalpy–entropy compensation is still not observed in this less polar solvent

Interplay of Surface Energy and Bulk Thermodynamic Forces in Ordered Block Copolymer Droplets

The wetting state of a simple liquid on a solid substrate, as summarized by Young’s equation, is dictated by the interfacial energies of the different phases that coexist in the system. For simple fluids, rotational symmetry gives rise to symmetric droplets around the axis perpendicular to the substrate. This is not the case for nanostructured fluids, such as block copolymers, where the inherent thermodynamic ordering forces compete with surface tension. This competition is particularly important in nanoscale droplets, where the size of the droplets is a small multiple of the natural periodicity of the block copolymer in the bulk. In the nanoscale regime, droplet shape and internal structure arise from a subtle interplay between interfacial and bulk contributions to the free energy. In this work, we examine the consequences of surface–polymer interaction energies on droplet morphology through a concerted simulation and experimental effort. When the block copolymer is deposited on a neutral substrate, we find noncircular arrangements with perpendicular domains. However, when a preferential substrate is used, the resulting morphology depends on droplet size. In large droplets, we observe bottle-cap-shaped structures with a ring of perpendicular domains along the perimeter, while small droplets exhibit stripes of perpendicular domains

Selective Plasmon Enhancement of the 1.08 μm Nd³⁺ Laser Stark Transition by Tailoring Ag Nanoparticles Chains on a PPLN <i>Y</i>‑cut

Selective photoluminescence enhancement of the specific Nd³⁺ Stark transition for which laser gain has been obtained in Nd³⁺/LiNbO₃ is demonstrated by means of plasmonic resonances with the appropriate symmetry configuration. By using the nonpolar <i>Y</i>-cut of a periodically poled LiNbO₃ crystal as platform for photoreduction of metallic nanostructures, periodically distributed chains of Ag nanoparticles oriented parallel to the ferroelectric <i>c</i>-axis are obtained. This alternative metallic nanostructure configuration supports the resonance between the localized surface plasmon and exclusively the π-polarized Stark laser line of Nd³⁺ ions at 1.08 μm, while maintaining the remaining crystal field transitions unchanged. The work provides the experimental proof on how plasmonic-based optical antennas can be used to influence selectively rare earth optical Stark transitions to improve the performance of solid state laser gain media