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The gas flaring network is an inseparable constituent commonly present in most of the oil and gas refineries and petrochemical facilities conferring reliable operational parameters. The improper disposal of burn-off gases improperly results in environmental problems and loss of economic resources. In this regard, waste to energy transforming nexus, in accord with the "carbon neutrality" term, has potentially emerged as a reasonable pathway to preserve our planet. In a transdisciplinary manner, the present review article deeply outlines the different up-to-date strategies developed to recover the emitted gases (flaring minimization) into different value-added products. To analyze the recovery potential of flare gases, different technologies, and decision-making factors have been critically reviewed to find the best recovery methods. We recommend more straightforward recovery methods despite lower profits. In this regard, electricity generation seems to be an appropriate option for application in small amounts of flaring. However, several flare gas utilization processes such as syngas manufacturing, reinjection of gas into petroleum reservoirs, and production of natural gas liquid (NGL) are also recommended as options because of their economic significance, technological viability (both onshore and offshore), and environmental benefits. Moreover, the adopted computational multi-scale data assimilation for predictive modeling of flare gas recovery scenarios has been systematically reviewed, summarized, and inspected.
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Gases , Gás Natural , Indústria de Petróleo e Gás , Petróleo , Modelos TeóricosRESUMO
PURPOSE: The aim of our study is to compare anterior and posterior corrections of thoracic (Lenke I) and lumbar (Lenke V) curves when modern posterior pedicle screw systems with vertebral derotation techniques are used. Curves that could not be corrected with both systems were excluded. METHODS: A thoracic group (N = 56) of Lenke I AIS patients (18 anterior and 38 posterior) and a lumbar group (N = 42) of Lenke V patients (14 anterior and 28 posterior) with similar curves < 65° were identified. RESULTS: Thoracic group The mean postoperative correction (POC) was 68 ± 13.4% in the anterior and 72 ± 10.5% in the posterior group. The postoperative change in thoracic kyphosis was +4° and +5° respectively. The median length of fusion was eight segments in the posterior and seven segments in the anterior groups. In 89% the LIV was EV or shorter in the anterior, and in 71% of the posterior corrections. Lumbar group The mean POC was 75 ± 18.3% (anterior) and 72 ± 8.5% (posterior). The postoperative gain in lumbar lordosis was 0.8° (anterior) and 4° (posterior). The median length of fusion was five segments in both groups and there was no difference in relation of the LIV to the EV. CONCLUSION: With modern implants and derotation techniques, the posterior approach can achieve similar coronal correction, apical derotation and thoracic kyphosis with similar length of fusion and better lumbar lordosis restoration.
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Cifose , Vértebras Lombares , Parafusos Pediculares , Escoliose , Fusão Vertebral , Vértebras Torácicas , Humanos , Fusão Vertebral/métodos , Fusão Vertebral/instrumentação , Cifose/cirurgia , Cifose/diagnóstico por imagem , Vértebras Lombares/cirurgia , Vértebras Torácicas/cirurgia , Vértebras Torácicas/diagnóstico por imagem , Feminino , Masculino , Adolescente , Escoliose/cirurgia , Escoliose/diagnóstico por imagem , Resultado do Tratamento , Estudos Retrospectivos , Lordose/cirurgia , Lordose/diagnóstico por imagemRESUMO
Recent studies have indicated that many challenges exist in implementing open user innovation in SMEs. As a more advanced paradigm of traditional innovation, open user innovations are developed by users and other stakeholders who share tasks and costs of innovation development and then freely unwrap results. The work presented in this article examines the main factors driving open user innovation in SMEs, operating in industries with low investment in R&D. The work accounts for differences in the economics categorisation of the countries in which the organisations operate in (developing vs developed), and how that impacts various factors related to open user innovation adoption. The findings of this study indicate that differences between Australian and Kuwaiti SMEs exist, in terms of perceptions of success, benefits, challenges, and ease of implementation related to open user innovation. In addition, some differences are observed in the drivers for sensing open user innovation opportunities between the two countries examined.
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BACKGROUND: ALPPS popularity is increasing among surgeons worldwide and its indications are expanding to cure patients with primarily unresectable liver tumors. Few reports recommended limitations or even contraindications of ALPPS in perihilar cholangiocarcinoma (phCC). Here, we discuss the results of ALPPS in patients with phCC in a systematic review as well as a pooled data analysis. METHODS: MEDLINE and Web of Science databases were systematically searched for relevant literature up to December 2023. All studies reporting ALPPS in the management of phCC were included. A single-arm meta-analysis of proportions was carried out to estimate the overall rate of outcomes. RESULTS: After obtaining 207 articles from the primary search, data of 18 studies containing 112 phCC patients were included in our systematic review. Rates of major morbidity and mortality were calculated to be 43% and 22%, respectively. The meta-analysis revealed a PHLF rate of 23%. One-year disease-free survival was 65% and one-year overall survival was 69%. CONCLUSIONS: ALPPS provides a good chance of cure for patients with phCC in comparison to alternative treatment options, but at the expense of debatable morbidity and mortality. With refinement of the surgical technique and better perioperative patient management, the results of ALPPS in patients with phCC were improved.
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Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) is a two-stage procedure that can potentially cure patients with large cholangiocarcinoma. The current study evaluates the impact of modifications on the outcomes of ALPPS in patients with cholangiocarcinoma. In this single-center study, a series of 30 consecutive patients with cholangiocarcinoma (22 extrahepatic and 8 intrahepatic) who underwent ALPPS between 2011 and 2021 was evaluated. The ALPPS procedure in our center was modified in 2016 by minimizing the first stage of the surgical procedure through biliary externalization after the first stage, antibiotic administration during the interstage phase, and performing biliary reconstructions during the second stage. The rate of postoperative major morbidity and 90-day mortality, as well as the one- and three-year disease-free and overall survival rates were calculated and compared between patients operated before and after 2016. The ALPPS risk score before the second stage of the procedure was lower in patients who were operated on after 2016 (before 2016: median 6.4; after 2016: median 4.4; p = 0.010). Major morbidity decreased from 42.9% before 2016 to 31.3% after 2016, and the 90-day mortality rate decreased from 35.7% before 2016 to 12.5% after 2016. The three-year survival rate increased from 40.8% before 2016 to 73.4% after 2016. Our modified ALPPS procedure improved perioperative and postoperative outcomes in patients with extrahepatic and intrahepatic cholangiocarcinoma. Minimizing the first step of the ALPPS procedure was key to these improvements.
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Perioperative medication management in patients who are nil by mouth for surgery or endoscopy is often suboptimal. Inappropriate medication management can prolong postoperative recovery and increase morbidity and mortality. This quality improvement study, carried out in general surgical patients at an 800-bed general hospital, aimed to improve perioperative medication management in accordance with the recommendations of the UK Clinical Pharmacy Association Handbook of Perioperative Medicine. Increasing awareness and educating general surgical team members, including doctors and non-medical prescribers, about perioperative medication management led to a non-significant improvement in medication management. However, a statistically significant improvement was achieved when nursing staff were also included. This study highlights the importance of involving different members of the multidisciplinary team in perioperative medication management.
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INTRODUCTION: The decision to instrument to L5 or ilium, in NMS, is usually based on radiologic factors, including pelvic obliquity (PO) > 15°, apex of curvature < L3, and Cobb angle > 60°. Since scoliosis in these patients is caused by a neurologic disease, we based our decision to stop at L5 on the presence of spasticity or flaccidity. PATIENTS & METHODS: The senior author did 109 primary fusions in NMS. Of those with DMD or SMA only 16% were instrumented to the ilium. The main factor for our decision was the correction potential of the truncal shift and PO in the supine traction radiographs and the absence of severe spasticity. RESULTS: The 57 patients with DMD/SMA had a mean preoperative curvature of 68°, PO of 17°, and truncal shift of 20°. 74% should have been instrumented to the pelvis, but only 16% were. Those instrumented shorter as the rule, were corrected from 74° to 26° and had a postoperative PO of 8°. There was no significant difference in postoperative correction and PO compared to those instrumented to L5 on standard protocol. Subsequent extension to the pelvis was needed in 1 CP patient. There were no significant changes after 2 years. Of the 20 patients instrumented to the pelvis 11 had cerebral palsy and a preop curvature of 89°, a PO of 21° and a truncal shift of 25°. DISCUSSION: The decision on instrumentation length should take flexibility and disease into consideration. If the trunk is centred over the pelvis, deterioration will not occur in absence of spasticity.
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Doenças Neuromusculares , Escoliose , Fusão Vertebral , Humanos , Escoliose/diagnóstico por imagem , Escoliose/cirurgia , Escoliose/etiologia , Vértebras Lombares/cirurgia , Resultado do Tratamento , Estudos Retrospectivos , Doenças Neuromusculares/complicações , Doenças Neuromusculares/diagnóstico por imagem , Doenças Neuromusculares/cirurgia , Pelve/diagnóstico por imagem , Pelve/cirurgia , Fusão Vertebral/métodosRESUMO
OBJECTIVES: To propose a novel framework for COVID-19 vaccine allocation based on three components of Vulnerability, Vaccination, and Values (3Vs). METHODS: A combination of geospatial data analysis and artificial intelligence methods for evaluating vulnerability factors at the local level and allocate vaccines according to a dynamic mechanism for updating vulnerability and vaccine uptake. RESULTS: A novel approach is introduced including (I) Vulnerability data collection (including country-specific data on demographic, socioeconomic, epidemiological, healthcare, and environmental factors), (II) Vaccination prioritization through estimation of a unique Vulnerability Index composed of a range of factors selected and weighed through an Artificial Intelligence (AI-enabled) expert elicitation survey and scientific literature screening, and (III) Values consideration by identification of the most effective GIS-assisted allocation of vaccines at the local level, considering context-specific constraints and objectives. CONCLUSIONS: We showcase the performance of the 3Vs strategy by comparing it to the actual vaccination rollout in Kenya. We show that under the current strategy, socially vulnerable individuals comprise only 45% of all vaccinated people in Kenya while if the 3Vs strategy was implemented, this group would be the first to receive vaccines.
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Vacinas contra COVID-19 , COVID-19 , Humanos , Inteligência Artificial , COVID-19/epidemiologia , COVID-19/prevenção & controle , Transporte Biológico , Análise de Dados , VacinaçãoRESUMO
The pulverized manifestation of Pedalium murex seeds, excerpted by Soxhlets apparatus after treating with n-hexane. Oil sample was well scrutinized by EI-GC-MS, utilizing the full scan technique within mass ranges lies from 40-700 m/z. 73compounds were recognized among them, 63 compounds were identified and 10 were marked as unidentified (8, 22, 27, 43, 47, 61, 62, 64, 68 and 69). The method was executed by the conventional system of Mass spectroscopy and the data interpreted by considerable match factor ≥95 inspected by NIST library. Antidiabetic activity was carried out by Accu-Chek glucometer. Healthy albino mice were selected to perform antidiabetic activity of seed oil at 100mg/Kg and 200mg/Kg with a standard drug glibenclamide at 5mg/Kg. Antidiabetic activity was observed on 1st, 7th,14th, 21th,27th and 30th days. Statistical calculations and significant outcomes were obtained by One-way and Two-way analysis of variance, followed by Tuckey's test. The phytochemical n-hexadecanoic acid (19.53%) might be responsible for antidiabetic activity of the seed oil.
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Hipoglicemiantes , Sementes , Camundongos , Animais , Cromatografia Gasosa-Espectrometria de Massas , Hipoglicemiantes/farmacologia , Espectrometria de Massas , Óleos de Plantas/farmacologiaRESUMO
The nuclear factor erythroid 2-like 2 (NFE2L2; NRF2) signaling pathway is frequently deregulated in human cancers. The critical functions of NRF2, other than its transcriptional activation, in cancers remain largely unknown. Here, we uncovered a previously unrecognized role of NRF2 in the regulation of RNA splicing. Global splicing analysis revealed that NRF2 knockdown in non-small cell lung cancer (NSCLC) A549 cells altered 839 alternative splicing (AS) events in 485 genes. Mechanistic studies demonstrated that NRF2 transcriptionally regulated SMN mRNA expression by binding to two antioxidant response elements in the SMN1 promoter. Post-transcriptionally, NRF2 was physically associated with the SMN protein. The Neh2 domain of NRF2, as well as the YG box and the region encoded by exon 7 of SMN, were required for their interaction. NRF2 formed a complex with SMN and Gemin2 in nuclear gems and Cajal bodies. Furthermore, the NRF2-SMN interaction regulated RNA splicing by expressing SMN in NRF2-knockout HeLa cells, reverting some of the altered RNA splicing. Moreover, SMN overexpression was significantly associated with alterations in the NRF2 pathway in patients with lung squamous cell carcinoma from The Cancer Genome Atlas. Taken together, our findings suggest a novel therapeutic strategy for cancers involving an aberrant NRF2 pathway.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Atrofia Muscular Espinal , Humanos , Células HeLa , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas do Complexo SMN/genética , Proteínas do Complexo SMN/metabolismo , Proteínas de Ligação a RNA/genética , Atrofia Muscular Espinal/genética , Atrofia Muscular Espinal/metabolismo , Atrofia Muscular Espinal/terapia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neurônios Motores/metabolismo , Splicing de RNA/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismoRESUMO
Traditional methods for designing concrete mixtures provide good results; however, they do not guarantee the optimum composition. Consequently, applying operational research techniques is motivated by an increasing need for designers to proportion the concrete's raw materials that satisfy the concrete performance requirements such as mechanical properties, chemical properties, workability, sustainability, and cost. For this reason, many authors have been looking for mathematical programming and machine learning solutions to predict concrete mix properties and optimise concrete mixtures. Therefore, a comprehensive review of operational research techniques concerning the design and proportioning of concrete mixtures and a classification framework are presented herein.
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Pannexin 1 (PANX1) is expressed in many tissue types including tissues of neural origin. Neuroblastoma (NB) is a neural crest-derived malignancy mainly occurring in children. The majority of NB patients present with high-risk disease for which current therapies are ineffective. Here, we show that while PANX1 is expressed in NB of all stages, high PANX1 expression in high-risk NB is associated with a reduced survival probability. PANX1 channel inhibition using probenecid (PBN) or carbenoxolone (CBX) reduced the proliferation of our panel of high-risk NB cell lines. We show that expression of the Y10F PANX1 mutant, which cannot be phosphorylated on tyrosine 10 and acts in a dominant-negative manner, curtailed NB cell proliferation. Furthermore, PBN and CBX treatment halted the growth of NB spheroids and in some cases triggered the regression of established NB spheroids. Finally, both drugs reduced the progression of high-risk NB in vivo. Together our data indicate that PANX1 channels regulate human NB malignant properties and that the use of PBN or CBX may provide a new therapeutic approach for high-risk NB.
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BACKGROUND: Patients with diabetic kidney disease (DKD) are at increased risk to develop post-contrast acute kidney injury (AKI). Diabetic patients under dipeptidyl peptidase 4 inhibitors (DPP4Is) experience a lower propensity to develop AKI. We speculated that linagliptin as a single agent or in combination with allopurinol may reduce the incidence of post-contrast AKI in stage 3-5 chronic kidney disease (CKD) patients with underlying DKD. METHODS: Out of 951 DKD patients eligible for this study, 800 accepted to sign informed consent. They were randomly allocated to 4 equal groups that received their prophylaxis for 2 days before and after radiocontrast. The first control group received N-acetyl cysteine and saline, the 2nd received allopurinol, the 3rd group received linagliptin, and the 4th received both allopurinol and linagliptin. Post-procedure follow-up for kidney functions was conducted for 2 weeks in all patients. RESULTS: 20, 19, 14, and 8 patients developed post-contrast AKI in groups 1 through 4, respectively. Neither linagliptin nor allopurinol was superior to N-acetyl cysteine and saline alone. However, the combination of the two agents provided statistically significant renal protection: post-contrast AKI in group 4 was significantly lower than in groups 1 and 2 (p < 0.02 and <0.03, respectively). None of the post-contrast AKI cases required dialysis. CONCLUSION: Linagliptin and allopurinol in combination may offer protection against post-contrast AKI in DKD exposed to radiocontrast. Further studies are needed to support this view. TRIAL REGISTRATION CLINICALTRIALS.GOV: NCT03470454.
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Injúria Renal Aguda , Alopurinol , Meios de Contraste , Nefropatias Diabéticas , Linagliptina , Substâncias Protetoras , Humanos , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/prevenção & controle , Alopurinol/administração & dosagem , Alopurinol/uso terapêutico , Nefropatias Diabéticas/classificação , Nefropatias Diabéticas/complicações , Nefropatias Diabéticas/diagnóstico , Falência Renal Crônica/complicações , Falência Renal Crônica/diagnóstico , Linagliptina/administração & dosagem , Linagliptina/uso terapêutico , Estudos Prospectivos , Insuficiência Renal Crônica/classificação , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/diagnóstico , Meios de Contraste/efeitos adversos , Quimioprevenção/métodos , Quimioterapia Combinada , Acetilcisteína/administração & dosagem , Acetilcisteína/uso terapêutico , Substâncias Protetoras/administração & dosagem , Substâncias Protetoras/efeitos adversos , Substâncias Protetoras/uso terapêutico , Solução Salina/administração & dosagem , Solução Salina/uso terapêuticoRESUMO
Escherichia coli ST1485 strains belong to the clinically important phylogroup F and have disseminated worldwide in humans, animals, and the environment. Here, we elucidated the pathogenome of a global collection of E. coli ST1485 isolates from diverse sources retrieved from public databases and a high-quality sequenced complete genome of colistin-resistant E. coli strain CFSAN061771 isolated from raw milk cheese which designated as a reference strain. CFSAN061771 belongs to O83:H42-ST1485 pathotype and carries a conjugative ColV plasmid, pCFSAN061771_01, combining extraintestinal virulence genes (ompt, sitA, iroN, etsC, traT, cvaC, hylF, iss, tsh, mchf, iucC, iutA) with a multidrug resistance island (blaTEM-1, aph(6)-Id, aph(3â³)-Ib, sul2, dfrA14). Comparative genomic analysis revealed a high frequency of pCFSAN061771_01-like plasmids in E. coli ST1485. A notable evolutionary genetic event in E. coli ST1485 strains is the acquisition of a pCFSAN061771_02-like plasmid, which confers resistance to several antimicrobials, tellurium, and quaternary ammonium compounds. The identical virulence and antibiotic resistance profiles identified in some human and animal strains are worrisome. This is the first study to emphasize the significance of E. coli ST1485 as a global high-risk virulent and multidrug-resistant clone with zoonotic potential.
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Infecções por Escherichia coli , Proteínas de Escherichia coli , Animais , Humanos , Escherichia coli , Filogenia , Infecções por Escherichia coli/genética , Plasmídeos/genética , Colistina , Proteínas de Escherichia coli/genética , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genéticaRESUMO
Purpose: Although surgery is associated with an acceptable cure rate, tumor recurrence is still a challenging issue in hepatocellular carcinoma (HCC) patients. Red blood cell distribution width (RDW) is considered an inflammatory marker for predicting overall mortality in a wide spectrum of malignancies. In the current study, the prognostic role of pre- and postoperative RDW in HCC recurrence after liver resection (LRx) is investigated. Patients and Methods: In 395 patients, RDW levels were evaluated preoperatively as well as six and twelve months after curative LRx. The RDW cutoff values were determined using receiver operating characteristic curves (ROCs) according to the recurrence-free survival (RFS). Survival analyses were performed using the Kaplan-Meier, and differences were compared using the Log rank test. Results: The RFS was significantly higher among patients with low RDW at the 6th month and 12th month, postoperatively (P < 0.001 and P = 0.028). RDW levels of higher than 16.15% at the 6th (HR: 2.047, P <0.001) and higher than 15.85% at 12th (HR: 3.105, P < 0.002) months after liver resection were independent predictors of RFS. Conclusion: Postoperative RDW values seem to be predictive of tumor recurrence in HCC patients. RDW levels at the 6th and 12th months postoperatively were independent predictors of recurrence after LRx.
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Sensor nodes are the building blocks of wireless sensor networks (WSNs), which may gather, analyze, and transmit various types of information to a certain destination. Data collection and transmission to the destination are the main responsibilities of sensor nodes at specified time intervals. However, one of the biggest issues with WSNs is the creation of energy-efficient wireless network algorithms. In this paper, a multi-hop multi-antenna power beacon path selection (MMPS) protocol is proposed. The proposed approach consists of a source, a destination, relays, power beacons generating radio frequency (RF) signals for energy harvesting, and eavesdroppers. We used physical layer security associated with energy harvesting to protect data from eavesdroppers without requiring higher layer data encryption and enhance the energy consumption of wireless networks. The signal's broadcast strength must be high enough to allow for energy harvesting while being low enough to prevent eavesdropping. The process continues until the data reaches the destination. Comparing the performance of MMPS with those of conventional methods, MMPS enhanced the wireless network outage probability (OP) up to 99.7%, life time, energy consumption, protection from eavesdroppers, and more resistant to hardware impairments which increased the immunity up to 95%.
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Redes de Comunicação de Computadores , Tecnologia sem Fio , Algoritmos , Segurança Computacional , Ondas de RádioRESUMO
PURPOSE: We compared two techniques for thoracic apical derotation; one using conventional reduction screws (Single-Innie-SI) and one requiring special derotation screws that can be converted to monoaxial screws to enhance dorotation (Dual-Innie-DI) for coronal and sagittal correction and. METHODS: A total of 200 patients with thoracic AIS have been included. In the SI-Group (n = 127) the convex rod was applied first. Vertebral derotation was done by translation to the concave rod with the convex rod being in place and center of rotation (COR). In the DI-Group (n = 73) correction started with translation on the concave side as well but now followed by derotation around the concave rod using the DI-mechanism. RESULTS: The mean rotation according to Raimondi and coronal correction was not sig. affected (72 (± 12) % in the SI-Group versus 68 (± 15) % in the DI-Group), even when flexibility was respected (Cincinnati Correction Index CCI was 2.9 (± 4.9) versus 3.5 (± 4.4). (p < 0.01). The gain of kyphosis was sig greater (2.7°) in the SI-group, but not clinical relevant. CONCLUSION: The use of DI screws for apical derotation did not provide an advantage for coronal correction or derotation in thoracic curves. Presumably after translation is performed in the DI-group, there was too much tension and friction in the construct impeding further derotation. Simultaneous translation and derotation in the SI-group, with the convex rod being the COR, yielded similar correction with better kyphosis and was faster and more economic.
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Cifose , Escoliose , Fusão Vertebral , Humanos , Escoliose/cirurgia , Fusão Vertebral/métodos , Parafusos Ósseos , Cifose/cirurgia , Rotação , Vértebras Torácicas/cirurgia , Resultado do Tratamento , Estudos RetrospectivosRESUMO
The mechanical properties of concrete are the important parameters in a design code. The amount of laboratory trial batches and experiments required to produce useful design data can be decreased by using robust prediction models for the mechanical properties of concrete, which can save time and money. Portland cement is frequently substituted with metakaolin (MK) because of its technical and environmental advantages. In this study, three mechanical properties of concrete with MK, i.e., compressive strength (f'c), splitting tensile strength (fst), and flexural strength (FS) were modelled by using four machine learning (ML) techniques: gene expression programming (GEP), artificial neural network (ANN), M5P model tree algorithm, and random forest (RF). For this purpose, a comprehensive database containing detail of concrete mixture proportions and values of f'c, fst, and FS at different ages was gathered from peer-reviewed published documents. Various statistical metrics were used to compare the predictive and generalization capability of the ML techniques. The comparative study of ML techniques revealed that RF has better predictive and generalization capability as compared with GEP, ANN, and M5P model tree algorithm. Moreover, the sensitivity and parametric analysis (PA) was carried out. The PA showed that the most suitable proportions of MK as partial cement replacement were 10% for FS and 15% for both f'c and fst.
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Compressive strength (CS) and splitting tensile strength (STS) are paramount parameters in the design of reinforced concrete structures and are required by pertinent standard provisions. Robust prediction models for these properties can save time and cost by reducing the number of laboratory trial batches and experiments needed to generate suitable design data. Silica fume (SF) is often used in concrete owing to its substantial enhancements of the engineering properties of concrete and its environmental benefits. In the present study, the M5P model tree algorithm was used to develop models for the prediction of the CS and STS of concrete incorporating SF. Accordingly, large databases comprising 796 data points for CS and 156 data records for STS were compiled from peer-reviewed published literature. The predictions of the M5P models were compared with linear regression analysis and gene expression programming. Different statistical metrics, including the coefficient of determination, correlation coefficient, root mean squared error, mean absolute error, relative squared error, and discrepancy ratio, were deployed to appraise the performance of the developed models. Moreover, parametric analysis was carried out to investigate the influence of different input parameters, such as the SF content, water-to-binder ratio, and age of the specimen, on the CS and STS. The trained models offer a rapid and accurate tool that can assist the designer in the effective proportioning of silica fume concrete.
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The treatment options for neuropathic pain caused by lumbar disc herniation have been debated controversially in the literature. Whether surgical or conservative therapy makes more sense in individual cases can hardly be answered. We have investigated whether a machine learning-based prediction of outcome, regarding neuropathic pain development, after lumbar disc herniation treatment is possible. The extensive datasets of 123 consecutive patients were used to predict the development of neuropathic pain, measured by a visual analogue scale (VAS) for leg pain and the Oswestry Disability Index (ODI), at 6 weeks, 6 months and 1 year after treatment of lumbar disc herniation in a machine learning approach. Using a decision tree regressor algorithm, a prediction quality within the limits of the minimum clinically important difference for the VAS and ODI value could be achieved. An analysis of the influencing factors of the algorithm reveals the important role of psychological factors as well as body weight and age with pre-existing conditions for an accurate prediction of neuropathic pain. The machine learning algorithm developed here can enable an assessment of the course of treatment after lumbar disc herniation. The early, comparative individual prediction of a therapy outcome is important to avoid unnecessary surgical therapies as well as insufficient conservative therapies and prevent the chronification of neuropathic pain.