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Assets deteriorate over time, as well as being covered, corroded, or becoming old in less obvious ways. Maintenance can extend the remaining useful life (RUL) of an asset system, but sooner or later it must surely be replaced. In this study, we propose a new RUL estimation methodology to assist in decision making for the maintenance and replacement of assets from prioritizing equipment in a renovation plan. Our methodology uses advanced data analysis techniques that consider multiple competing criteria with the goal of maximizing values of the asset throughout its life cycle, while considering the rules of remuneration and service quality of the current regulation, as well as the values at risk according to the decisions and actions taken. Experimental results with real datasets show the efficiency of the proposed approach. Finally, this work also presents the development of an analytical tool to optimize asset renewal decisions applying the RUL estimation methodology proposed and its application to the Brazilian electric sector.

An anterior cruciate ligament (ACL) tear is a severe sports injury that often occurs in young athletes. Besides the strong cumulative evidence on noncontact ACL tears, the injury mechanism (especially the contribution of external rotation) is still not well understood. The present work aims to evaluate which knee kinetics result in higher ACL stress and strain. A finite element model of the ACL was developed with a detailed geometry; the two distinct bundles (anteromedial and posterolateral) and the surrounding connective tissue were modelled based on medical anatomic measures and images. The model was validated using computational and cadaveric external data. Sixteen simulations were performed using different combinations of moments and axial loads applied to the knee model as boundary conditions. The results demonstrated that the peak stress (11.00 MPa) and strain (0.048) occurred at the midportion of the anteromedial bundle with the higher values being obtained under a combined knee valgus, flexion, tibial external rotation and high axial load. Anterior load showed low sensitivity in ACL stress and strain peaks. The tibial external rotation showed a higher contribution to the peak ACL stress and strain as compared to internal rotation. These results reinforce the role of axial load and highlight the importance of external rotation on ACL stress and strain, which may be suggestive of the ACL tear mechanism. The role of external rotation is often neglected and should be further explored in future cadaveric and experimental studies. The findings of this study provide data-driven insights to optimize the indications for prevention, diagnosis and treatment of ACL injuries in clinical practice and contribute to raising awareness of the injury mechanism among all relevant stakeholders.

Introduction: Healthcare associated infections due to carbapenem-resistant Klebsiella pneumoniae (CRKP) are a major concern in Portuguese hospitals. Whole genome sequencing (WGS) can improve infection control, but this practice is not routinely used by hospital clinical laboratories in Portugal. We simulated the investigation of a CRKP outbreak based on WGS, with the aim of determining, in the minimum possible time, genetic relatedness between CRKP clinical and environmental isolates. Material and Methods: Ten CRKP clinical isolates routinely obtained in the hospital laboratory were used. Forty environmental samples - from sinks and sink drains of ward rooms - were collected. Environmental samples were plated on selective media and presumptive CRKP colonies were isolated. Total DNA was extracted from all putative CRKP isolates and sequenced. Clonal relatedness was determined by multi-locus sequence typing and core genome single nucleotide polymorphism analysis; the presence of carbapenemase genes was evaluated. Results: Clinical isolates were characterized in 48 hours: eight strains were confirmed as CRKP, of which six were of ST13 and carried blaKPC-3. Environmental samples results were obtained in six days: eight CRKP were isolated from which five were of ST13 and carried blaKPC-3. Clinical and environmental ST13 isolates were highly related: ten (of 11) isolates differed from each other in < 0.001% of 2 172 367 core nucleotides. Discussion: WGS can be used as a high-resolution effective tool to investigate healthcare associated infections and track routes of dissemination in real-time. Conclusion: In Portugal, routine use of WGS to improve infection control could thrive through collaborative initiatives between hospitals and research institutes.

O aumento da competitividade entre as empresas, a globalização dos mercados, a constante necessidade de estar se adaptando a novas tecnologias, o maior nível de exigência dos clientes e a menor disponibilidade de recursos financeiros estão fazendo com que o setor da construção civil venha sofrendo várias alterações nos últimos anos, de tal forma que as empresas passaram a sentir necessidade de implantar e aprimorar os sistemas de planejamento e gerenciamento dos processos existentes. O presente trabalho tem o propósito de apresentar como a Teoria da Corrente Crítica pode ser utilizada no planejamento e gestão de obras de construção civil. Diante disso, foi realizado um estudo de caso em uma obra localizada na cidade de Fortaleza – CE, sendo abordado o processo de planejamento e monitoramento da respectiva obra, com foco no planejamento de médio prazo realizado e na utilização da Teoria da Corrente Crítica. As principais contribuições deste trabalho estão relacionadas às melhorias que podem ser proporcionadas ao gerenciamento de processos do setor da construção civil a partir da aplicação dos conceitos da Teoria da Corrente Crítica e do planejamento de médio prazo, resultando em um aumento da produtividade, uma redução do retrabalho e da multitarefa, uma maior integração e comprometimento por parte das equipes envolvidas no projeto, dentre outros benefícios.

Plutonium-238 is currently still the best fuel to power satellites to be sent to deep space in regions where the solar panels can no longer efficiently receive the sunlight. For 50 years, the National Aeronautics and Space Administration (NASA) has used this radioisotope as a fuel in radioisotope thermoelectric generators (RTGs) installed on satellites such as Pioneer 10 and 11, Voyager 1 and 2, Cassini-Huygens and New Horizons, as well as the various rovers sent to the Moon and to Mars, among others. Plutonium-238 is not a naturally occurring isotope on the planet, it was produced in greater quantity during the Cold War period as a by-product of the production of Plutonium-239 used for nuclear bombs. However, after the shutting down of the Savannah River reactors in 1988 and the ending of the Soviet Union in 1991, the United States stock of Plutonium-238 has been increasingly reduced, which threatens NASA's future space projects. This paper presents a brief bibliographic review about the subject, as well as commentaries on the options available to the United States, from restarting the production of this fuel, to possible alternatives for a new type of fuel or equipment that may supply the spacecrafts.

One of the great advances in the current evolution of nuclear power reactors is occurring in India, with the Advanced Heavy Water Reactor (AHWR). It is a reactor that uses thorium as part of its fuel, which in its two fueling cycle options, in conjunction with plutonium or low enriched uranium, produces energy at the commercial level, generating less actinides of long half-life and inert thorium oxide, which leads to an optimization in the proportion of energy produced versus the production of burnt fuels of the order of up to 50%. The objective of this work is to present the most recent research and projects in progress in India, and how the expected results should be in compliance with the current sustainability models and programs, especially the "Green Chemistry", a program developed since the 1990s in the United States and England, which defines sustainable choices in its twelve principles and that can also be mostly related to the nuclear field. Nevertheless, in Brazil, for more than 40 years there has been the discontinuation of research for a thorium-fueled reactor, and so far there has been no prospect of future projects. The AHWR is an important example as an alternative way of producing energy in Brazil, as the country has the second largest reserve of thorium on the planet.

In the second half of the twentieth century in Brazil, several nuclear facilities were built for the most varied objectives. The largest number of such facilities is at the Nuclear and Energy Research Institute in São Paulo (IPEN-CNEN/SP). For different reasons, some of these facilities had their projects finalized and were deactivated. Some of the equipment was then dismantled, but the respective nuclear and radioactive material remained isolated in the original sites awaiting the proper decommissioning procedures. The Celeste Project is an example of a facility where the nuclear material has been kept, and is subject to Argentine-Brazilian Agency for Accounting and Control of Nuclear Materials (ABACC) periodic inspections. Because of a number of interests, including financial and/or budgeting situations at the institutions, decades have passed without any further action, and the people who withold information and knowledge about these facilities have already moved away from the area or are in the process of. Therefore, because of the absence of knowledge management techniques in force at the time of establishing and operating these installations, this work proposes an analysis about the possible consequences in case of loss of perhaps the only one remaining knowledge, the one from the people who designed those departments and worked there.

Abstract Background Chronic obstructive pulmonary disease (COPD) is associated with several extra-pulmonary effects of which skeletal muscle wasting is one of the most common and contributes to reduced quality of life, increased morbidity and mortality. The molecular mechanisms leading to muscle wasting are not fully understood. Proteomic analysis of human skeletal muscle is a useful approach for gaining insight into the molecular basis for normal and pathophysiological conditions. Methods To identify proteins involved in the process of muscle wasting in COPD, we searched differentially expressed proteins in the vastus lateralis of COPD patients with low fat free mass index (FFMI), as a surrogate of muscle mass (COPDL, n = 10) (FEV1 33 ± 4.3% predicted, FFMI 15 ± 0.2 Kg.m−2), in comparison to patients with COPD and normal FFMI (COPDN, n = 8) and a group of age, smoking history, and sex matched healthy controls (C, n = 9) using two-dimensional fluorescence difference in gel electrophoresis (2D-DIGE) technology, combined with mass spectrometry (MS). The effect of silencing DOT1L protein expression on markers of cell arrest was analyzed in skeletal muscle satellite cells (HSkMSCs) in vitro and assessed by qPCR and Western blotting. Results A subset of 7 proteins was differentially expressed in COPDL compared to both COPDN and C. We found an increased expression of proteins associated with muscle homeostasis and protection against oxidative stress, and a decreased expression of structural muscle proteins and proteins involved in myofibrillogenesis, cell proliferation, cell cycle arrest and energy production. Among these was a decreased expression of the histone methyltransferase DOT1L. In addition, silencing of the DOT1L gene in human skeletal muscle satellite cells in vitro was significantly related to up regulation of p21 WAF1/Cip1/CDKN1A, a marker of cell arrest and ageing. Conclusions 2D-DIGE coupled with MS identified differences in the expression of several proteins in the wasted vastus lateralis that are relevant to the disease process. Down regulation of DOT1L in the vastus lateralis of COPDL patients may mediate the muscle wasting process through up regulation of markers of cell arrest and senescence.

In any wavelength sensitive application, extensive care should be taken in addressing the wavelength drift issues. In the case in which laser tuning is conducted by using thermoelectric cooler, an accurate expression is needed to describe transient characteristics of the Peltier device to achieve maximum controllability. In addition, thermal tuning issues are of particular relevance to the field of photonic integration. In this paper, the exact solution of the governing equation is presented, considering Joule heating, heat conduction, heat flux of the laser diode, and the thermoelectric effect in one dimension. In addition, the variable separation method and the Sturm-Liouville theorem, along with the completeness features of eigenfunctions, are used to obtain time-dependent electrical potential and temperature distribution of the Peltier device. Additionally, steady-state sensitivity analysis is performed in order to demonstrate the impacts of physical parameters on its thermoelectric characteristics. Transient temperature is also considered that, for a specific case, revealed fast transition to steady-state condition with time constant lower than 400 ms. Lower heat capacity, as well as laser diode heat flux, might lead to faster Peltier response times, such that the effect of heat flux on response time becomes negligible in low heat capacity Peltier.

Patellar dislocation is a major orthopaedic concern in pediatric and adult populations, with both conservative and surgical options available. Several surgical techniques of the combined or isolated reconstruction of the medial patellofemoral ligament are described in the literature using different grafts, locations, and types of fixations, providing different advantages and disadvantages. New recent developments in cadaveric dissection studies have unveiled the importance of structures that were neglected until recently, such as the medial quadriceps tendon–femoral ligament, which provides a connection between the medial femur and the quadriceps tendon component of the knee extensor mechanism. Hence, we present a surgical technique with combined reconstruction of the medial patellofemoral ligament and medial quadriceps tendon–femoral ligament without the use of hardware and with no need for patellar or femoral drilling (no physis compromise or risk of patellar fracture), which can be used concomitantly with other bony procedures.

Knee osteoarthritis (OA) is a common condition in the older population and is characterized by several articular dysfunctions with consequent anatomic abnormalities including osteochondral degenerative changes and meniscal extrusion. Meniscal damage with extrusion is one of the strongest identified risk factors for the development and progression of knee OA and represents an important factor in the long-term health of the joint. Meniscal extrusion can alter normal knee biomechanics and dramatically inhibit meniscal function. We present a surgical technique for the treatment of early knee OA in association with an extruded meniscus to restore the meniscal anatomic position and preserve its native physiological function related to cartilage preservation. Meniscal retensioning, or a “meniscal autotransplant,” can increase meniscal coverage in the compromised compartment, prevent cartilage degeneration, decrease subchondral bone exposure, and restore the compartmental space and, consequently, can relieve patients' symptoms related to early OA.

Patellar tendon ruptures can lead to significant functional deficiency of the extensor mechanism of the knee. These injuries, because of their inherent nature and associated complications, may require a complex treatment and remains a challenge for orthopaedic surgeons. Current surgical techniques present significant complications, including patellar fracture, damage to patellar articular cartilage, and abnormal patella height. This note describes a surgical technique to provide an additional reinforcement to the patellar tendon repair with a semitendinous autograft, without the necessity to perform any transosseous tunnels at the patella bone. First, the patellar tendon is repaired with an end-to-end technique and the semitendinous tendon is harvested. A transosseous tunnel at the tibial tubercle is drilled and 2 rents are made, both medial and lateral to the retinaculum at the level of the intermedial segment of the patella close to the patellar margin. The graft is passed through the tunnel and rents in a U-shaped form. The graft is sutured along the length of the patellar tendon on both margins in tension at 30° of knee flexion. Fluoroscopy imaging is performed to assess the patella height. This technique provides a significant augmentation of patellar tendon, avoiding the potential patella bone tunnel complications.

Patellofemoral dysfunction, due to either a patellofemoral malalignment or patellar instability, is a complex and debilitating condition that significantly decreases the knee function. Conservative management may yield significant clinical outcomes; however, when morphologic anomalies are identified, the surgical approach should be employed. Hence, several surgical procedures have been described in the scientific literature aiming the correction of underlying extensor mechanism malalignments. Still, the rate of complications is higher than desirable. The described technique is based on the principles of transferring the tibial tubercle medially as described in the Elmslie-Trillat technique. However, a curvilinear horizontal cut is made prior to the vertical cut, which raises a thick osseous fragment and allows the formation of a gutter when the osseous fragment is moved medially. Whereas the horizontal gutter provides stability to the bone fragment, the thicker dimension of the osseous fragment and retention of the distal attachment significantly enhances the osteotomy union. Hence, adequate pain relief and stability with very low postoperative morbidity could be achieved. The purpose of this surgical note is to describe a modification to the Elmslie-Trillat technique to treat patellofemoral dysfunctions, achieving a higher osseous stability and decreased postoperative morbidity.

There are promising results in the use of platelet-rich plasma (PRP) for musculoskeletal tissue repair. However, the variability in the methodology for its obtaining may cause different and opposing findings in the literature. Particularly, the choice of the anticoagulant is the first definition to be made. In this work, blood was collected with sodium citrate (SC), ethylenediaminetetraacetic acid (EDTA), or anticoagulant citrate dextrose (ACD) solution A, as anticoagulants, prior to PRP obtaining. Hematological analysis and growth factors release quantification were performed, and the effects on mesenchymal stromal cell (MSC) culture, such as cytotoxicity and cell proliferation (evaluated by MTT method) and gene expression, were evaluated. The use of EDTA resulted in higher platelet yield in whole blood; however, it induced an increase in the mean platelet volume (MPV) following the blood centrifugation steps for PRP obtaining. The use of SC and ACD resulted in higher induction of MSC proliferation. On the other hand, PRP obtained in SC presented the higher platelet recovery after the blood first centrifugation step and a minimal change in MSC gene expression. Therefore, we suggest the use of SC as the anticoagulant for PRP obtaining.

The editorial in Frontiers in Toxicology focuses on toxicology research in Central and South America, covering topics such as new psychoactive substances, ethanol, corticosterone, atrazine, and hexavalent chromium. The research explores the effects of these substances on various experimental models, from invertebrates to vertebrates. The articles highlight the urgent need for regulation of new psychoactive substances and the importance of scientific research in addressing emerging threats to public health. Additionally, the research emphasizes the environmental and health risks associated with herbicides and the significance of using invertebrates as experimental models in toxicology studies. [Extracted from the article]