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This study assesses the economic and environmental implications of Sustainable Aviation Fuel (SAF) production using Alcohol-to-Jet (ATJ) and Gasification Fischer-Tropsch (GFT) technologies, focusing on Colombian lignocellulosic feedstocks and evaluating key performance indicators such as yield, minimum fuel selling price, and life cycle assessment. GFT demonstrates promising results, yielding and Minimum Fuel Selling Price (MFSP) of about 1.3 USD/L and a Life Cycle Assessment (LCA) of 3.2 to 7.7 gCO2 eq/MJ. However, its scalability is constrained by the volumes it manages. On the other hand, ATJ has an MFSP between 1.9 and 2.4 USD/L. Aligned with aviation industry goals for carbon-neutral growth, this analysis provides valuable insights for policymakers and industry stakeholders, supporting informed decisions toward sustainable aviation fuel adoption in the Colombian context.

Abstract Background Surgical reconstruction of the posterior cruciate ligament (PCL) can be technically challenging given the proximity of the popliteal artery to the PCL tibial insertion. This "no-safe zone" makes some knee surgeons less confident and willing to perform this surgical procedure. Surgical technique We present a PCL tibial inlay reconstruction technique using a set of instruments involving three tools (a slot cut, a bone plug positioner, and an impactor). Conclusion This set of instruments allows a more reproducible posteromedial approach and to produce a PCL tibial slot in a posterior cruciate ligament inlay reconstruction with the patient supine in bicruciate ligament injury reconstruction.

ABSTRACT Objective: The aim of this study was to compare the stress distribution in internal tapered connection implants with different adaptation geometries submitted to oblique load simulation using the Finite Element Analysis (FEA) method. Methods: Three different internal tapered implant-abutment assemblies were modeled by varying only the diameter of the abutment body in the cone region. The dimensions of the implants were 4.0 mm in diameter and 13 mm in length. Oblique loads of 210 N angled 30 degrees to the long axis of the implant were applied to a hemispherical body positioned over the abutments simulating a dental crown. The stress generated by the implant-abutment assembly was analyzed by the FEA method using the von Mises criterion. Results: A higher concentration of stress in the coronal region (collar) and implant body on the opposite side of the load application was shown, as well as in the body region of the abutments and in the screw threads. The cervical region of the implants showed the highest von Mises stress values, the highest values being observed in G3 (1034 MPa), followed by G2 (841 MPa) and G1 (702 MPa). Conclusion: According to the results presented, it can be concluded that the stress distribution was more homogeneous and less concentrated in the G1 implant-abutment assembly. Therefore, the use of abutments with dimensions standardized by the implant manufacturer is recommended.

ABSTRACT Objective: By analyzing our cases of posterior cruciate ligament (PCL) tibial avulsion fracture, we noted that a U-shaped image was present in the anteroposterior plain radiographs view of the affected knee, even in cases where the profile view of the knee had been inconclusive as to tibial PCL avulsion fracture, a “hidden” fracture. Therefore, we aimed to investigate whether there was an anatomical correlation between this radiological U sign and the tibial insertion of the PCL and to ascertain the intra- and inter-rater reliability of this sign in clinical practice. Methods: The data of the widths and heights area of the PCL tibial insertion area, and the U sign area were measured and compared to the largest width of the tibia. Two moreover, the reliability and reproducibility of this imaging were analyzed. Results: The areas height of the U-sign area and the anatomical insertion area of the posterior cruciate ligament showed no difference, and both were topographically located in the two central quarters of the proximal end of the tibia. The radiographic assessment showed excellent Kappa agreement rates between interobserver and intraobserver, with high reliability and reproducibility. Conclusion: The U sign is a radiographic feature of PCL tibial avulsion fracture seen on the radiograph AP view, there is a high association between the ratios of the U-sign area height in the X-ray and the anatomical height of the PCL tibial insertion site MRI with the largest width of the proximal tibia. The radiographic U sign showed excellent rates of interobserver and intraobserver agreement with Kappa values higher than 0.8. Level of Evidence IV; Dignostic Studies - Investigating a Diagnostic Test.

Abstract Narrow‐diameter implants (≤3.5 mm) have been proposed to address the challenge of implant placement in cases of insufficient bone quantity, thin alveolar crest, and small cervical diameter teeth replacement The aim of this study is to report one‐year outcomes of extra‐narrow implant rehabilitation of maxillary lateral incisors, due to agenesis, in a young adult that presented sites with reduced mesiodistal and buccolingual dimensions. A 26‐year‐old male patient in need of fixed‐implant supported prostheses due to the absence of permanent maxillary lateral incisors and with limited space, was submitted to surgery to receive two 2.9 mm hybrid Morse taper connection implants with hydrophilic surfaces. Immediate loading was applied by means of insertion of provisional prostheses, which were replaced for all‐ceramic prostheses 12 months after surgery. The 1 year follow‐up showed clinical and radiographic success of extra‐narrow implant rehabilitation. Also, both regions presented good evolution of peri‐implant esthetics, as assesses using the pink esthetic score, with improvements at 4 months follow‐up and reaching high scores 12 months after surgery. Although the prosthetic rehabilitation of maxillary lateral incisors is challenging due to limited space for the insertion of implants, the clinical case suggests that the use of extra‐narrow Morse Taper implants with hybrid design and hydrophilic surface is a reliable alternative, presenting good outcomes regarding hard and soft tissue and it is a versatile solution or immediate loading procedure. Further studies are needed to confirm extra‐narrow implant predictability.

Abstract This case report describes the treatment of two patients who presented with single edentulous sites in the region of upper premolars and were rehabilitated through the placement of injection‐molded 2‐piece zirconia implants and immediate single crowns. Three months after surgery, definitive prostheses were confectioned through digital workflow. Both patients were followed for 12 months during which clinical and radiographic implant success were observed, concerning implant stability, absence of peri‐implantitis signs, complete implant osseointegration, good marginal bone‐level maintenance, and excellent soft tissue esthetics. No biological or mechanical complications were observed within this period.

Abstract Background The horn fly Haematobia irritans is a blood-sucking ectoparasite responsible for substantial economic loss of livestock. Like other hematophagous arthropods species, the successful blood-feeding of H. irritans is highly dependent on the modulation of the host’s hemostasis and immune system. Here, we evaluated the biological activity of hematobin (HTB), a protein recently identified in the H. irritans saliva, on macrophage biology. The goal was to understand the putative interactions between the components of H. irritans saliva and the early host immune responses. Results Thioglycolate-elicited peritoneal macrophages from BALB/c mice were stimulated by lipopolysaccharide (LPS) plus interferon-γ (IFN-γ) in the presence or absence of recombinant HTB. The presence of the salivary protein in the cultures inhibited nitric oxide production and decreased the inducible nitric oxide synthase (iNOS) expression induced by LPS plus IFN-γ. The tumor necrosis factor-α (TNF-α) and interleukin-12p40 (IL-12p40) levels were also reduced in the macrophages pre-incubated with HTB; these findings correlated to the decreased NF-κB expression. The biological activities described here were not associated with changes in annexin V binding to macrophages suggesting that HTB does not induce cell death. In addition, the activity of HTB seems to be specific to macrophages because no changes were observed in lymphocyte proliferation or cytokine production. Conclusions We describe here the first bioactive salivary protein of H. irritans. We characterized its ability to modulate macrophage inflammatory response, and the results can help explain how horn flies modulate the host immune system to feed on blood.

This study presents a rigorous approach for the extraction of the modulus of soil and unbound aggregate base materials for quality management using intelligent compaction (IC) technology. The proposed approach makes use of machine-learning methods in tandem with IC technology and modulus-based spot testing as a local calibration process to estimate the mechanical properties of compacted geomaterials. A calibrated three-dimensional finite element (FE) model that simulates the proof-mapping process of compacted geomaterials was used to develop a comprehensive database of responses of a wide range of single and two-layered geosystems. The database was then used to develop different inverse solvers using artificial neural networks for the estimation of the modulus from the characteristics of the roller and information about the geomaterials. Several instrumented test sites were used for the evaluation and validation of the inverse solvers. The proposed approach was found promising for the extraction of the modulus of compacted geomaterials using IC. The accuracy of the inverse solvers is enhanced if a local calibration process is incorporated as part of a quality management program that includes the use of in situ measurements using modulus-based test devices and laboratory resilient modulus testing. Moreover, compaction uniformity plays a key role in the retrieval of the modulus of geomaterials with certainty. The proposed approach fuses artificial intelligence with mechanistic solutions to position IC as a technology that is well suited for the quality management of compacted materials.

Abstract Introduction The long-term implant-supported prosthetic rehabilitation monitoring is extremely important in evaluating parameters that could interfere in the success of the treatment. Objective To evaluate the influence of macrodesign (shape of the body and apex), length and diameter, insertion torque, site of installation as well as the loading protocol, on long-term survival rates. Material and method The data obtained was from the medical records of rehabilitated patients who had had at least one Morse taper implant surgery done at ILAPEO School between 2006 -2012. Incomplete medical records, from which it would have been impossible to extract all data essential to complete the study, were excluded. Result A total of 1,142 patient’s medical records comprised the sample; documenting the progress of 5,601 implants, done in both jaws and mandibles. The final survival rate was 98.31%, over an average time of 37.54 months. The type of implant most used was cylindrical (70.33%). The mean installation torque most evidenced in the study was between 41 and 50 Ncm. A logistical regression analysis showed that none of the following variables, site of installation, body and apex shape designs and length, had any significant statistical influence on implant loss. Torque increase and diameter influenced implant loss while immediate loading favored implant maintenance. Conclusion It can be concluded that Morse taper implants present a long-term survival rate that can be lowered by excessive torque, as well as by the diameter of the implant.

This paper examines the impact of information on psychology of music on Stress and Anxiety Levels of Brazilian students of music performance, both undergraduate and graduate, and cross information on their levels of stress and anxiety. It includes an investigation on curricular programs of Brazilian public universities based on previous investigation by the authors (RAY; et al, 2011). The main goals: 1) to investigate how much information Brazilian music performance students has access to access during their courses; and 2) to identify potential indicators of the impact this information may have on the levels of stress and anxiety in the performances of these students; Methodology: Students from six Brazilian public universities were requested to fill out three forms: the Kenny Music Performance Anxiety Inventory (K-MPAI); the Inventory of Stress Symptoms LIPP and an additional form that investigated the participants routine for preparation to performance. Results: information on music performance psychology is only presented privately at teacher’s discretion. As compulsory classes have not been included in the curriculum, it was not possible to infer results on this subject. More than half of the participants (51,72%) don’t present stress condition. Almost half of them (48,27%) have some level of stress. All participants fit within some level of anxiety.

Este trabalho teve por finalidade analisar o comportamento de tendões calcâneo bovino submetidos a ensaios mecânicos cíclicos. Para cada corpo de prova foram aplicados três ensaios de dez ciclos de tração e três níveis de deformação: 2,5%, 3% e 4%. Ao término de cada ensaio o tendão era mantido em repouso por 300 s. A velocidade de carregamento adotada foi de 10% do comprimento do corpo de prova, por segundo. Os resultados obtidos foram submetidos à análise de variância com delineamento de parcelas subdivididas no tempo e blocos casualizados nas subparcelas. Conclui-se que o pré-tensionamento de tendões realizado através da deformação relativa permanece como parâmetro mais seguro, por atuar dentro dos limites fisiológicos do tendão, evitando os efeitos nocivos do sobretensionamento.This research work reports an experimental study on the mechanical behavior of bovine calcaneous tendons. A total number of 03 cyclic relaxation tests with 10 cycles respectively at 2,5%, 3%, and 4% of deformation were performed for each specimen. The specimens were kept at rest for 300 s between tests. Deformation rates were maintained at 10% of initial length per second. Cyclic relaxation tests carried on all tendons showed that the average force correspondent to the first cycle was statistically significatively greater than the average force correspondent to the tenth cycle. This also emphasizes the occurrence of a force relaxation phenomena. It can be concluded that tendons pre-tensionning by means of specific deformations stands for a safer parameter because it acts within the tendon biological limits avoyding the overtensioning negative effects.

A lesão do ligamento cruzado anterior do joelho (LCA) é um problema que afeta tanto os animais como os seres humanos, e pode evoluir com instabilidade articular, muitas vezes, sintomática e incapacitante para o paciente. Os enxertos de tendões autólogos são a principal opção como substitutos ligamentares. Durante a reconstrução cirúrgica do LCA, o enxerto é submetido a tensionamento com o objetivo de restabelecer a lassidão normal do joelho LCA-deficiente. Embora o tensionamento do enxerto exerça papel fundamental na evolução clínica pós-operatória, a literatura ainda não estabeleceu os níveis ideais de tensionamento a serem aplicados. Assim, o estiramento ou elongamento do enxerto que pode ocorrer com o passar do tempo permanece como uma das principais causas da falha da reconstrução ligamentar.Neste trabalho, dez tendões de calcâneo bovino foram submetidos a dois ensaios sucessivos de tensionamento fisiológico a deformação relativa máxima de 2.5% do comprimento inicial do tendão ensaiado, mantida durante 600s, sendo registrados os valores de força (N) no tempo zero (inicial), 300s e 600s. Ao término do primeiro ensaio, o tendão retornava ao seu comprimento inicial, sendo mantido em repouso durante 300s, seguido de novo ensaio de tensionamento repetindo-se os mesmos procedimentos anteriores. A análise estatística permitiu concluir que o elongamento do tendão é mais pronunciado nos 300s iniciais, refletindo uma queda mais acentuada nos valores da tensão do enxerto. Portanto, 300s após o tensionamento e fixação do enxerto, o cirurgião pode avaliar mais adequadamente se o nível de tensionamento foi suficiente.

A anatomia é considerada matéria essencial à educação médica. Aulas práticas com uso de componentes anatômicos manipuláveis são fundamentais ao ensino e à aprendizagem. O objetivo deste estudo foi avaliar o Modelo Sintético de Pelve (Masp) como ferramenta didática, comparada à pelve cadavérica (PC) tradicionalmente utilizada, bem como a satisfação dos estudantes em relação a ambos os métodos. Sessenta e sete estudantes receberam aula teórica após teste teórico preliminar (TTP). Foram randomizados em três grupos: G1 teve aula prática tradicional (APT); G2, aula prática com Masp (APM); e G3 não teve aula prática. Um teste final (TTF) foi aplicado a todos os grupos. G1 e G2 submeteram-se à avaliação do método (AM). A análise estatística foi realizada utilizando-se Anova (Análise de Variância) e teste não paramétrico Mann-Whitney. No TTF, G3 apresentou escores mais baixos do que G1 (p = 0,041) e G2 (p = 0,000). Não foi encontrada diferença estatisticamente significante entre G1 e G2 (p >0,05). G2 apresentou maior satisfação com o método (p = 0,001). Concluiu-se que PC e Masp provaram ser ferramentas didáticas efetivas e que G2 mostrou maior satisfação.

Abstract Background Experimental studies have shown that repetitive trans-spinal magnetic stimulation (TsMS) decreases demyelination and enables recovery after spinal cord injury (SCI). However, the usefulness of TsMS in humans with SCI remains unclear. Therefore, the main objective of this study is to evaluate the effects of TsMS combined with kinesiotherapy on SCI symptoms. We describe a protocol treatment with TsMS and kinesiotherapy in a patient with SCI due to neuromyelitis optica (NMO)-associated transverse myelitis. Case presentation A 23-year-old white male with NMO spectrum disorders started symptoms in 2014 and included lumbar pain evolving into a mild loss of strength and sensitivity in both lower limbs. Five months later, the symptoms improved spontaneously, and there were no sensorimotor deficits. Two years later, in 2016, the symptoms recurred with a total loss of strength and sensitivity in both lower limbs. Initially, physiotherapy was provided in 15 sessions with goals of motor-sensory recovery and improving balance and functional mobility. Subsequently, TsMS (10 Hz, 600 pulses, 20-seconds inter-trains interval, at 90% of resting motor threshold of the paravertebral muscle) was applied at the 10th thoracic vertebral spinous process before physiotherapy in 12 sessions. Outcomes were assessed at three time points: prior to physiotherapy alone (T-1), before the first session of TsMS combined with kinesiotherapy (T0), and after 12 sessions of TsMS combined with kinesiotherapy (T1). The patient showed a 25% improvement in walking independence, a 125% improvement in balance, and an 18.8% improvement in functional mobility. The Patient Global Impression of Change Scale assessed the patient’s global impression of change as ‘much improved’. Conclusion TsMS combined with kinesiotherapy may safely and effectively improve balance, walking independence, and functional mobility of patients with SCI due to NMO-associated transverse myelitis.

Abstract A combined injury of the patellar tendon and both the anterior and posterior cruciate ligaments is disabling. It directly affects knee kinematics and biomechanics, presenting a considerable surgical challenge. In this complex and uncommon injury, decision-making should take into account the surgeon’s experience and consider one- or two-stage surgery, tendon graft, graft fixation, and rehabilitation protocol. This manuscript discusses the surgical approach based on a comprehensive understanding of the patellar tendon and bicruciate biomechanics to guide which structures should be reconstructed first, especially when a two-stage procedure is chosen.

Abstract Different surgical techniques have been proposed to reconstruct combined anterior cruciate (ACL) and lateral collateral ligaments (LCL). Although these surgical techniques are reliable and reproducible, the number of autologous grafts needed for the reconstruction could be a limiting factor, especially when patients present with multi-ligament knee injuries and the posterior cruciate ligament is also torn. In addition, some of these techniques are not easy to master and have a steep learning curve. We present a surgical procedure that has been used over the last 18 years to reconstruct combined ACL and LCL injuries and has become a reproducible, feasible and time-efficient procedure to approach combined ACL and LCL injuries using an ipsilateral hamstring autograft.

ABSTRACT Objective: To analyze the functional outcomes after arthroscopic treatment of femoroacetabular impingement (FAI). Methods: 194 patients (131 males and 63 females), with a mean age of 39 (15-68) years old for men and 43 (16-58) years old for women. The average follow-up was 17 months (2 to 71). 103 patients presented Cam-type FAI, 102 mixed and 25 Pincer. “Unilateral” arthroscopy was performed in 161 cases, “Bilateral” (only once each side) in 46 cases and, “Multiple” (more than one procedure on the same hip) in 23. The female sex was prevalent in the Pincer type FAI (76%), while males were prevalent in Mixed and Cam type, 74.5% and 72.8%, respectively. Results: The mean HHSpre score was 63.7 and 87.1 for HHSpost, i.e. 73.11%. Differences appeared between “mixed” and “unilateral” groups. The complications percentage in this series was 18.7% and 7% progressed to total hip arthroplasty. Conclusion: The arthroscopic FAI treatment improved the postoperative clinical scores of these patients, especially in cases of mixed-type FAI, which presented a higher improvement rate. Insufficient femoral osteoplasty was the main cause for surgical re-intervention, particularly in the initial cases of this series. Level of Evidence II, Retrospective study.

ABSTRACT Objective: To correlate clinical and intraoperative findings with the postoperative evaluation of two-stage bicruciate knee ligament reconstruction. Methods: The study was conducted with 25 patients (20 men and 05 women) with mean age of 32.3 years, mean body mass index (BMI) of 26.2, and mean lesion duration of 18.3 months. The treatment consisted of an Inlay reconstruction of the posterior cruciate ligament (PCL) followed by the anterior cruciate ligament (ACL) reconstruction, at least 3 months after the first surgical procedure. Four patients required additional procedures: patellar tendon (02), medial collateral ligament (MCL) (02). Results: With an average follow-up of 24.8 months, 60% of the patients scored zero or + at the posterior drawer test, while 40% scored ++; 60% of patients were evaluated as good/excellent according to the Lysholm scale. Only one patient reached the pre-injury Tegner activity level. Injury duration had a negative influence on functional limitation, vitality, and mental health (SF-36). Conclusion: Although two-stage bicruciate knee ligament reconstruction improved knee stability and self-assessment, 96% of patients did not recover their pre-injury state. In the 36-item short form survey (SF-36), injury duration was inversely correlated with self-assessment of functional capacity, physical limitation, vitality, and mental health. Level of Evidence II, retrospective study.