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1.
Arch Orthop Trauma Surg ; 144(8): 3337-3342, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39105840

RESUMEN

BACKGROUND: Developmental Dysplasia of the Hip (DDH) is a condition affecting hip joint development in children, presenting multiple manifestations. Immobilization methods to ensure hip concentricity, such as the human position and modified Lange position, vary in effectiveness and risks, especially avascular necrosis. The purpose of this study was to identify whether closed reduction (CR), with two different immobilization techniques, is effective in avoiding complications such as residual hip dysplasia (RHD), re-dislocation, and Avascular Necrosis (AVN). METHODS: A total of 66 patients with DDH (84 hips) were treated with two different techniques of immobilization (groups A and B); the mean age at the time of reduction was 8 (6-13) months. The rates of RHD, Re-dislocation, and AVN were determined with a minimum follow-up of 48 months in both techniques. RESULTS: The Chi-square analysis conducted across the study groups unveiled that patients in Group B demonstrated a protective effect against AVN compared to those in Group A (OR: 0.248, 95% CI: 0.072-0.847, p = 0.026). However, no statistically significant differences were found between the groups concerning RHD (p = 0.563) and re-dislocation (p = 0.909). CONCLUSIONS: After the initial Human Position immobilization, the second cast with the modified Lange "second position" demonstrated a protective effect compared with maintaining the Human Position immobilization throughout the immobilization period, reducing the likelihood of AVN development in patients undergoing closed reduction for developmental dysplasia of the hip.


Asunto(s)
Displasia del Desarrollo de la Cadera , Necrosis de la Cabeza Femoral , Humanos , Masculino , Femenino , Necrosis de la Cabeza Femoral/prevención & control , Necrosis de la Cabeza Femoral/etiología , Displasia del Desarrollo de la Cadera/cirugía , Lactante , Posicionamiento del Paciente/métodos , Complicaciones Posoperatorias/prevención & control , Estudios Retrospectivos , Luxación Congénita de la Cadera/terapia
2.
Artículo en Inglés | MEDLINE | ID: mdl-39109775

RESUMEN

The urinary volume and residual urine volume are pieces of information that can provide relevant clinical data for dogs and cats, especially those hospitalized. Thus, the present study aimed to evaluate mathematical formulas described in human and veterinary literature to estimate urinary volume in dogs and experimental models. For this purpose, nine male dog cadavers and twelve experimental models were used to evaluate residual volume, small, medium, and large, using three different formulas. Data were obtained by three different examiners: two ultrasonographers and one nonultrasonographer. Each examiner recorded three longitudinal and transverse images, obtaining measurements of width, length, and height at each proposed volume. The measurements were then averaged, and the result was added to the formulas, thus estimating urinary volume. All three formulas achieved higher accuracy in estimating smaller volumes, with a gradual decrease as urinary volume increased. The error of all formulas was less than 10%, even when compared with evaluations in experimental models and dogs. There was variation in estimation between ultrasonographers and nonultrasonographer examiners; however, this variation was low, allowing for the assertion that both can apply the technique. Thus, it is concluded that estimating urinary bladder volume using mathematical formulas and 2D ultrasound is accurate and, therefore, an alternative and viable option for evaluating the urinary tract.

3.
Int J Infect Dis ; 147: 107165, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38977240

RESUMEN

OBJECTIVE: The effects of sanitation and hygiene interventions on the gut microbiome and enteric pathogen burden are not well understood. We measured the association between free chlorine residue (FCR) levels in drinking water, microbiome composition, and stool enteric pathogens in infants and young children in Haiti. METHODS: FCR levels were measured in household drinking water and enteric pathogen burden was evaluated using multiplex RT-PCR of stool among 131 children from one month to five years of age living in Mirebalais, Haiti. Microbiome profiling was performed using metagenomic sequencing. RESULTS: Most individuals lived in households with undetectable FCR measured in the drinking water (112/131, 86%). Detection of enteric pathogen DNA in stool was common and did not correlate with household water FCR. The infant microbiome in households with detectable FCR demonstrated reduced richness (fewer total number of species, P = 0.04 Kruskall-Wallis test) and less diversity by Inverse Simpson measures (P = 0.05) than households with undetectable FCR. Infants in households with a detectable FCR were more likely to have abundant Bifidobacterium. Using in vitro susceptibility testing, we found that some Bifidobacterium species were resistant to chlorine. CONCLUSIONS: FCR in household drinking water did not correlate with enteric pathogen burden in our study.


Asunto(s)
Cloro , Agua Potable , Heces , Microbioma Gastrointestinal , Humanos , Haití/epidemiología , Cloro/farmacología , Agua Potable/microbiología , Lactante , Preescolar , Microbioma Gastrointestinal/efectos de los fármacos , Heces/microbiología , Masculino , Femenino , Purificación del Agua
4.
Clin Ophthalmol ; 18: 1909-1914, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39055380

RESUMEN

Purpose: To validate a new methodology to evaluate the impact of astigmatism in pseudophakia using an astigmatic defocus curve. Setting: Hospital Oftalmológico de Brasilia, Brazil. Design: Non-randomized cohort study. Methods: For every point of the defocus curve, from -2.00 to +3.00 with 0.50D intervals, visual acuity was assessed with optically induced astigmatism (0.50D, 1.00D and 1.50D at 90 and 180 degrees) in pseudophakic patients implanted with a refractive-enhanced intraocular lens. Results: Twelve patients were analyzed. A statistically significant difference was found between the 90° (ATR) and 180°(WTR) axis with 1.50D astigmatism, providing better visual acuity in ATR astigmatism (p < 0.05). Conclusion: This new methodology is reproducible, useful and may predict residual astigmatism tolerance in pseudophakic patients, which may help with surgery planning and IOL decision-making.

5.
J Environ Sci Health B ; 59(8): 497-506, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38958072

RESUMEN

The objective was to evaluate the efficacy of pre-emergence herbicides mixture applied to the soil with and without dead cover crops (Sorghum bicolor) for the control of Amaranthus hybridus L. (smooth pigweed) and its selectivity in soybeans. This study was structured in split plot (2 × 6 + 2), where factor A plots (with and without dead cover) and factor B six herbicides mixture: flumioxazin + S-metolachlor (50.4 + 1,008 g a.i. ha-1), flumioxazin + imazethapyr (60 + 127.2 g a.i. ha-1), pyroxasulfone + sulfentrazone (137.6 + 160 g a.i. ha-1), diuron + sulfentrazone (400 + 200 g a.i. ha-1), metribuzin + S-metolachlor (326.4 + 1,344 g a.i. ha-1) and sulfentrazone + imazethapyr (200 + 100 g a.i. ha-1) and two untreated control plots. As for the results, the herbicides flumioxazin + S-metolachlor, flumioxazin + imazethapyr and pyroxasulfone + sulfentrazone showed excellent control (97-99%) and were not influenced by the plot with and without dead cover. They also showed higher yield soybeans (<2,244 kg ha-1). All herbicides were selective to the soybeans. Overall, pre-emergence herbicides and cover crops were efficient methods for the control of A. hybridus, which farmers should use to avoid losses in yield soybeans due to weed competition.


Asunto(s)
Amaranthus , Glycine max , Herbicidas , Suelo , Herbicidas/farmacología , Amaranthus/efectos de los fármacos , Amaranthus/crecimiento & desarrollo , Glycine max/efectos de los fármacos , Glycine max/crecimiento & desarrollo , Suelo/química , Control de Malezas/métodos , Productos Agrícolas/crecimiento & desarrollo , Productos Agrícolas/efectos de los fármacos
6.
Int J Cardiol Cardiovasc Risk Prev ; 22: 200298, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38983606

RESUMEN

Background: The objective of this research is to evaluate the efficacy and safety of drugs in the residual risk in any of its three components: lipid, inflammatory and thrombotic risk. Methods: A systematic review was conducted of randomized clinical trials that included as a primary outcome, at least one of the conditions related to atherosclerotic cardiovascular disease. The databases used were PUBMED/MEDLINE, Scopus and ClinicalTrials.gov. The risk of bias of the studies was assessed using the Risk of Bias 2 tool. Results: and discussion: 18 studies were included in the analysis. Half of the studies had low risk of bias or some concerns. Several drugs were effective in reducing the primary outcome: ethyl eicosapentaenoeic acid (17.2 % E-EPA versus 22 % placebo HR: 0.75; 95 % CI 0.68-0.83; p < 0.001), colchicine in stable coronary artery disease (6.8 % vs placebo 9.6 %, HR 0.59, 95 % CI 0.57-0.83; p < 0.001), Canakinumab (150 mg vs placebo ARR 15 %, HR 0.85, 95 % CI 0.74-0.98; p = 0.021) and Rivaroxaban with Aspirin in stable atherosclerotic disease (4.1 % versus aspirin 5.4 %, HR 0.76, 95 % CI 0.66-0.86, P < 0.001). Serious adverse events did not differ between study groups, except for a higher rate of bleeding with the use of combination antithrombotic therapy. Conclusion: The residual risk can be reduced through the use of different drugs that act by modifying atherogenic lipid levels, modulating inflammatory pathways and the risk of thrombosis, with an acceptable safety profile in most studies.

7.
J Appl Stat ; 51(9): 1642-1663, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38933143

RESUMEN

The article proposes a new regression based on the generalized odd log-logistic family for interval-censored data. The survival times are not observed for this type of data, and the event of interest occurs at some random interval. This family can be used in interval modeling since it generalizes some popular lifetime distributions in addition to its ability to present various forms of the risk function. The estimation of the parameters is addressed by the classical and Bayesian methods. We examine the behavior of the estimates for some sample sizes and censorship percentages. Selection criteria, likelihood ratio tests, residual analysis, and graphical techniques assess the goodness of fit of the fitted models. The usefulness of the proposed models is red shown by means of two real data sets.

8.
Biotechnol Prog ; : e3491, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38934212

RESUMEN

The yeast cell wall is a complex structure whose main function is to protect the cell from physical and chemical damage, providing it with rigidity. It is composed of a matrix of covalently linked polysaccharides and proteins, including ß-glucans, mannoproteins, and chitin, whose proportion can vary according to the yeast species and environmental conditions. The main components of the yeast cell wall have relevant properties that expand the possibilities of use in different industrial sectors, such as pharmaceutical, food, medical, veterinary, and cosmetic. Some applications include bioremediation, enzyme immobilization, animal feed, wine production, and hydrogel production. In the literature it is the description of the cell wall composition of model species like Saccharomyces cerevisiae and Candida albicans, however, it is important to know that this composition can vary according to the species or the culture medium conditions. Thus, understanding the structural composition of different species holds promise as an alternative to expanding the utilization of residual yeast from different bioprocesses. In the context of a circular economy, the conversion of residual yeast into valuable products is an attractive prospect for researchers aiming to develop sustainable technologies. This review provides an overview of yeast cell wall composition and its significance in biotechnological applications, considering prospects to increase the diversification of these compounds in industry.

9.
Atherosclerosis ; 395: 117508, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-38570208

RESUMEN

BACKGROUND AND AIMS: Remnant cholesterol (RC) and insulin resistance (IR) have been independently associated with cardiovascular risk. Here, we evaluated the role of IR and RC on cardiovascular disease (CVD) mortality. METHODS: We conducted an analysis of 16,113 individuals ≥20 years without diabetes from the National Health and Nutrition Examination Survey (NHANES-III/IV). RC levels were calculated using total cholesterol, non-HDL-c, and LDL-c; IR was defined as HOMA2-IR≥2.5 and CVD mortality as a composite of cardiovascular and cerebrovascular mortality. Multiple linear regression was used to assess the relationship between HOMA2-IR and RC and Cox regression models to assess their joint role in CVD mortality. Causally ordered mediation models were used to explore the mediating role of IR in RC-associated CVD mortality. RESULTS: We identified an association between higher HOMA2-IR and higher RC levels. The effect of IR on CVD mortality was predominant (HR 1.32, 95%CI 1.18-1.48) and decreased at older ages (HR 0.934, 95%CI 0.918-0.959) compared to RC (HR 0.983, 95%CI 0.952-1.014). Higher risk of CVD mortality was observed in individuals with IR but normal RC (HR 1.37, 95%CI 1.25-1.50) and subjects with IR and high RC (HR 1.24, 95%CI 1.13-1.37), but not in subjects without IR but high RC. In mediation models, HOMA2-IR accounted for 78.2% (95%CI 28.11-98.89) of the effect of RC levels on CVD mortality. CONCLUSIONS: Our findings suggest that RC potentiates the risk of CVD mortality through its effect on whole-body insulin sensitivity, particularly among younger individuals.


Asunto(s)
Enfermedades Cardiovasculares , Colesterol , Resistencia a la Insulina , Encuestas Nutricionales , Humanos , Masculino , Enfermedades Cardiovasculares/mortalidad , Enfermedades Cardiovasculares/sangre , Femenino , Persona de Mediana Edad , Adulto , Colesterol/sangre , Estados Unidos/epidemiología , Medición de Riesgo , Biomarcadores/sangre , Anciano , Factores de Riesgo de Enfermedad Cardiaca , Factores de Riesgo
10.
Front Oncol ; 14: 1304690, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38634051

RESUMEN

The main objective of the National Project for Research and Incidence of Childhood Leukemias is to reduce early mortality rates for these neoplasms in the vulnerable regions of Mexico. This project was conducted in the states of Oaxaca, Puebla, and Tlaxcala. A key strategy of the project is the implementation of an effective roadmap to ensure that leukemia patients are the target of maximum benefit of interdisciplinary collaboration between researchers, clinicians, surveyors, and laboratories. This strategy guarantees the comprehensive management of diagnosis and follow-up samples of pediatric patients with leukemia, centralizing, managing, and analyzing the information collected. Additionally, it allows for a precise diagnosis and monitoring of the disease through immunophenotype and measurable residual disease (MRD) studies, enhancing research and supporting informed clinical decisions for the first time in these regions through a population-based study. This initiative has significantly improved the diagnostic capacity of leukemia in girls, boys, and adolescents in the regions of Oaxaca, Puebla, and Tlaxcala, providing comprehensive, high-quality care with full coverage in the region. Likewise, it has strengthened collaboration between health institutions, researchers, and professionals in the sector, which contributes to reducing the impact of the disease on the community.

11.
Transl Anim Sci ; 8: txae005, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38525300

RESUMEN

Residual feed intake (RFI) has become a widely spread index of feed efficiency. Although most of beef cattle systems in the world are pasture based, RFI evaluation and research is usually performed in confinement conditions. In this context, residual heat production (RHP) estimated as the difference between actual and expected heat production (HP), could allow to identify efficient animals. Thus, the aim of this work was to evaluate the relationship between paternal estimated breeding values (EBV) for RFI and beef heifer efficiency, measured as RHP, as well as its association with heifers' productive and reproductive performance on grazing conditions. Seventy-one 25 ±â€…0.8-mo-old and seventy-four 24 ±â€…0.7-mo-old Hereford heifers were managed as contemporary groups in spring 2019 and 2020, respectively. Heifers were sired by 10 RFI-evaluated bulls and classified into three groups according to the paternal EBV for RFI: five bulls of low RFI (high efficiency, pHE), two bulls of medium RFI (medium efficiency), and three bulls of high RFI (low efficiency, pLE). The experimental period lasted 70 d prior to their first insemination where HP was determined by the heart rate-O2 pulse technique. In addition, reproductive performances during the first and second breeding and calving seasons were recorded. Heifers' RHPs expressed as MJ/d and kJ/kg of body weight (BW)0.75/d were positively correlated with paternal RFI EBVs (P < 0.05; r > 0.60). Moreover, BW and average daily gain (ADG) were greater (P < 0.01) for pHE than pLE heifers while expressed as units of BW0.75/d, neither total HP nor metabolizable energy (ME) intake differed between groups, but pHE heifers had greater retained energy (RE; P < 0.01) and lower RHP (P < 0.05) than pLE ones. Gross energy efficiency (RE/ME intake) was greater (P < 0.001) for pHE than pLE heifers while the HP/ADG and RHP/ADG were reduced (P < 0.05) and feed-to-gain ratio (ADG/DM intake) tended to be greater (P = 0.07) for pHE than pLE heifers. In addition, during the first breeding and calving seasons, small but significant (P < 0.01) differences in reproductive responses between groups suggested an earlier pregnancy in pHE heifers than the pLE group, differences that disappeared during the second breeding and calving seasons. Thus, heifers sired by high-efficiency bulls measured as RFI were more efficient measured as RHP in grazing conditions, without significant differences in reproductive performance.

12.
Heliyon ; 10(5): e26951, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38495194

RESUMEN

Steel cross-sections with thin walls are vulnerable to fire-induced buckling instability, which reduces their load-bearing capacity. Eurocode 3 design provisions have been found inadequate, leading to alternative methods such as effective design strategies and advanced structural models built mostly with shell FE, which can be complex. For Class 4 steel beam-columns subjected to fire conditions, beam-type modelling to predict the Flexural-Torsional Buckling (FTB) strength has been proposed as an alternative approach, but it has not yielded satisfactory results for large compressive load eccentricities. This paper presents two new low computational cost modelling strategies based on Timoshenko's beam FE to address this issue: the Single beam-column Model (SbcM) and the Cruciform beam-column Model (CbcM). The first consists of a single line of beam FE, while the second uses a grid of beam FE for more flexibility. Both strategies effectively simulate the FTB behaviour in Class 4 steel beam-column during a fire, offering quicker computations compared to shell models. Still, the single-line model is favoured for its simplicity, making it more efficient in analysing complex fire engineering problems.

13.
Clin Transl Oncol ; 26(9): 2198-2204, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38488982

RESUMEN

BACKGROUND: Managing residual and recurrent craniopharyngioma effectively is crucial for improving patient outcomes. This study evaluates the combined use of gamma knife and phosphorus-32 brachytherapy, offering insights into alternative, less invasive treatment strategies. METHODS: We conducted a retrospective analysis of 97 patients treated from 2010 to 2016 for residual and recurrent craniopharyngioma using gamma knife and phosphorus-32 brachytherapy. We classified these patients into three groups: superficial solid (Group A), simple cystic (Group B), and mixed cystic-solid (Group C). We assessed the treatment's effectiveness by the tumor control rates and evaluated safety by monitoring vision, endocrine function improvements, and complication rates. RESULTS: The treatment achieved complete and adequate control rates of 49.5% and 87.6%, respectively. We observed improvements in vision or visual fields in 55.1% of the patients. The morbidity rate was 15.5%. The study found no significant differences in tumor control rates among the various lesion types. CONCLUSION: The combination of gamma knife and phosphorus-32 brachytherapy presents a viable, minimally invasive alternative for treating residual and recurrent craniopharyngioma. It offers high tumor control and functional improvement rates, suggesting its potential as a preferred strategy in some instances.


Asunto(s)
Braquiterapia , Craneofaringioma , Recurrencia Local de Neoplasia , Neoplasia Residual , Neoplasias Hipofisarias , Radiocirugia , Humanos , Craneofaringioma/radioterapia , Braquiterapia/métodos , Estudios Retrospectivos , Femenino , Masculino , Neoplasias Hipofisarias/radioterapia , Recurrencia Local de Neoplasia/radioterapia , Adulto , Persona de Mediana Edad , Adolescente , Radiocirugia/métodos , Niño , Adulto Joven , Neoplasia Residual/radioterapia , Radioisótopos de Fósforo/uso terapéutico , Preescolar , Anciano , Terapia Combinada , Resultado del Tratamiento
14.
Neurophysiol Clin ; 54(1): 102939, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38382136

RESUMEN

BACKGROUND: Phantom pain limb (PLP) has gained more attention due to the large number of people with amputations around the world and growing knowledge of the pain process, although its mechanisms are not completely understood. OBJECTIVES: The aim of this study was to understand, in patients with amputations, the association between PLP and residual limb pain (RLP), and the brain metabolic response in cortical motor circuits, using functional near-infrared spectroscopy (fNIRS). METHODS: Sixty participants were recruited from the rehabilitation program in São Paulo, Brazil. Included patients were aged over 18 years, with traumatic unilateral lower-limb amputation, with PLP for at least 3 months after full recovery from amputation surgery. PLP and RLP levels were measured using visual analogue scales. fNIRS was performed during motor execution and motor mirror tasks for 20 s. In order to highlight possible variables related to variation in pain measures, univariate linear regression analyses were performed for both experimental conditions, resulting in four fNIRS variables (two hemispheres x two experimental conditions). Later, in order to test the topographic specificity of the models, eight multivariate regression analyses were performed (two pain scales x two experimental conditions x two hemispheres), including the primary motor cortex (PMC) related channel as an independent variable as well as five other channels related to the premotor area, supplementary area, and somatosensory cortex. All models were controlled for age, sex, ethnicity, and education. RESULTS: We found that: i) there is an asymmetric metabolic activation during motor execution and mirror task between hemispheres (with a predominance that is ipsilateral to the amputated limb), ii) increased metabolic response in the PMC ipsilateral to the amputation is associated with increased PLP (during both experimental tasks), while increased metabolic response in the contralateral PMC is associated with increased RLP (during the mirror motor task only); ii) increased metabolic activity of the ipsilateral premotor region is associated with increased PLP during the motor mirror task; iii) RLP was only associated with higher metabolic activity in the contralateral PMC and lower metabolic activity in the ipsilateral inferior frontal region during motor mirror task, but PLP was associated with higher metabolic activity during both tasks. CONCLUSION: These results suggest there is both task and region specificity for the association between the brain metabolic response and the two different types of post-amputation pain. The metabolic predominance that is ipsilateral to the amputated limb during both tasks was associated with higher levels of PLP, suggesting a cortical motor network activity imbalance due to potential interhemispheric compensatory mechanisms. The present work contributes to the understanding of the underlying topographical patterns in the motor-related circuits associated with pain after amputations.


Asunto(s)
Corteza Motora , Miembro Fantasma , Humanos , Adulto , Persona de Mediana Edad , Espectroscopía Infrarroja Corta , Brasil , Amputación Quirúrgica , Miembro Fantasma/rehabilitación , Extremidad Inferior
15.
Toxics ; 12(2)2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38393233

RESUMEN

In this research, the decomposition of toxic organics from pulp and paper mill effluent by the sequential application of ozonation and biodegradation was studied. Ozonation, as a pre-treatment, was executed to transform the initial pollutants into less toxic compounds (such as organic acids of low molecular weights). Biodegradation was executed during three days with acclimated microorganisms that were able to complete the decomposition of the initial organic mixture (raw wastewater) and to achieve a higher degree of mineralization (85-90%). Experiments were performed under three different conditions: (a) only ozonation of the initial contaminants, (b) only biodegradation of residual water without previous treatment by ozone and (c) ozonation followed by biodegradation performed by acclimated microorganisms. In the case of 72 h of biodegradation, the mineralization efficiency reached 85% and 89% after 30 and 60 min of ozonation, respectively. The no significant difference in this parameter coincided with the calculated generalized microorganisms' consortia specific growing rate µmax that was reduced from 2.08 × 10-3 h-1 to 6.05 × 10-4 h-1 when the ozonation time was longer. The identification of the organics composition by gas chromatography with mass detector (GC-MS) before and after treatments confirmed that the proposed combined process served as a more efficient alternative to secondary and tertiary treatments (mineralization degree between 60 and 80% in average) of the paper industry wastewater.

16.
Heliyon ; 10(3): e25348, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38327426

RESUMEN

It is mathematically shown that ductile fracture after finite plastic strain is a necessary consequence of the polycrystalline nature of the materials. A closed-form equation for the plastic strain to fracture of a fine-grained polycrystal with no voids is derived. The mathematical model for the plastic deformation is grounded on the physical hypothesis that adjacent grains slide with a relative velocity proportional to the local shear stress resolved in the plane of the shared grain boundary, when exceeds a finite threshold. Hence plastic flow is governed predominantly by the in-plane shear forces making grain boundaries to slide, and the induced local forces responsible for the continuous grain reshaping are much weaker. The process is shown to produce a monotonic hydrostatic pressure variation with strain that precludes a stationary flow. The hydrostatic pressure dependence on strain has two solutions. One of them leads to superplasticity, the other one is shown to diverge logarithmically at a finite fracture strain and then represents ductile behaviour. Emphasis is done in the mathematical aspects of the deformation of the polycrystal up to the initiation of fracture. Although theoretical predictions agree well with mechanical tests of commercial alloys, technical issues like the effects of the presence and evolution of porosity and other imperfections, or how fracture evolves after initiation are left for a more specific communication.

17.
Cancers (Basel) ; 16(2)2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38275885

RESUMEN

BACKGROUND: Soft tissue sarcomas are a group of rare neoplasms which can be mistaken for benign masses and be excised in a non-oncologic fashion (unplanned excision). Whether unplanned excision (UE) is associated with worse outcomes is highly debated due to conflicting evidence. METHODS: We performed a systematic review and meta-analysis following PRISMA guidelines. Main outcomes analyzed were five-year overall survival (OS), five-year local recurrence-free survival (LRFS), amputation rate and plastic reconstruction surgery rate. Risk ratios were used to compare outcomes between patients treated with planned and unplanned excision. RESULTS: We included 16,946 patients with STS, 6017 (35.5%) with UE. UE was associated with worse five-year LRFS (RR 1.35, p = 0.019). Residual tumor on the tumor bed was associated with lower five-year LRFS (RR = 2.59, p < 0.001). Local recurrence was associated with worse five-year OS (RR = 1.82, p < 0.001). UE was not associated with a worse five-year OS (RR = 0.90, p = 0.16), higher amputation rate (RR = 0.77, p = 0.134), or a worse plastic reconstruction surgery rate (RR = 1.25, p = 0.244). CONCLUSIONS: Unplanned excision of Soft Tissue Sarcomas and the presence of disease in tumor bed after one were associated with worse five-year LRFS. Tumor bed excision should remain the standard approach, with special consideration to the presence of residual disease.

18.
Meat Sci ; 209: 109397, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38043329

RESUMEN

This study evaluated the use of the S-nitrosothiols, S-nitroso-N-acetylcysteine (NAC-SNO) and S-nitroso-N-acetylcysteine ethyl ester (NACET-SNO), at different concentrations (25-300 mg nitrite equivalent - NEq/kg) as sodium nitrite substitutes in restructured cooked hams. The pH value and instrumental cured color were not affected by the type or amount of curing agent used. Products with 25 and 50 mg/kg ingoing nitrite had lower thiobarbituric acid-reactive substance values than those with equimolar amounts of S-nitrosothiols. Products with >150 mg NEq/kg of S-nitrosothiols had residual nitrite similar to 50 mg/kg nitrite, and this resulted in the same volatile compound profile as nitrite added in equimolar amounts. A 300 mg NEq/kg of S-nitrosothiols was required to obtain a similar and minimally stable cured pink color perception as sliced samples with 50-150 mg/kg added nitrite. The results obtained reinforce the great potential of both alternative curing agents in the complete replacement of nitrite by equimolar amounts in restructured cooked products; however, differences in cured color stability should be considered.


Asunto(s)
Acetilcisteína/análogos & derivados , Productos de la Carne , S-Nitrosotioles , Productos de la Carne/análisis , Nitrito de Sodio , S-Nitrosotioles/química , Lípidos
19.
Environ Sci Pollut Res Int ; 31(1): 1419-1441, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38040884

RESUMEN

A great complexity limits its use as the degree of aging of the asphalt binder of the RAP is a determinant for the interaction with the new binder and recycling agents to design asphalt mixtures with reclaimed asphalt pavement (RAP). One of the ways to analyze the level of interaction between the aged binder and the recycling agent is through the analysis of the performance of the mixtures after the accelerated aging of the samples in the laboratory. Thus, this paper evaluated the mechanical performance of asphalt mixtures with high contents of RAP (50%, 75%, and 100%) and organic type recycling agents (residual engine oil) and surfactant (ADCAP WM), submitted to aging protocols short and long term. The data obtained verified the feasibility of adding up to 75% of RAP in the recycled mixtures. However, detailed monitoring of its execution and performance throughout its useful life is necessary. Fatigue and flexural fracture data were highly altered by aging conditioning, evidencing the reduction in the performance of the compositions of the recycled mixtures. The statistical test showed significance for the parameters RAP content and type/content of the recycling agent used. In addition, there was an increase in the deformation capacity and better resistance to aging and cracking with the incorporation of the surfactant recycling agent.


Asunto(s)
Hidrocarburos , Laboratorios , Reciclaje , Tensoactivos
20.
Vet Res Commun ; 48(2): 685-694, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37851315

RESUMEN

This study aimed to evaluate the anesthetic activity of Ocimum basilicum essential oil and the distribution and depletion of its major compounds in different tissues of the pacu, Piaractus mesopotamicus. Juveniles (319.08 ± 9.14 g) were individually anesthetized with six concentrations of essential oil from O. basilicum (150, 180, 210, 240, 270, and 300 mg L-1), while in a second experiment, fish (492.39 ± 51.51 g) were subjected to a 10 min immersion bath with essential oil from O. basilicum (300 mg L-1). After anesthetic recovery, blood and tissue samples of the brain, gills, liver, spleen, and white muscle were collected at 0, 0.5, 1.0, 3.0, 6.0, 12.0, and 24 h. A 300 mg L-1 concentration induced anesthesia in the shortest time (193.11 ± 9.31), while at 270 and 300 mg L-1 concentrations, the anesthetic recovery period was the longest (244.33 ± 12.44) Methyl chavicol and linalool were quantified in all tissue samples. The plasma concentrations of methyl chavicol differed (p < 0.05) at all evaluated times. Linalool decreased (p < 0.05) from 0 to 1 h and decreased again only after 12 h. Reduction percentages in 24 h were 92.9% for methyl chavicol, and 97.2% for linalool. Elimination of the compounds methyl chavicol and linalool is slower in the gills, where lower elimination constants (0.03 and 0.15 per h) and longer half-lives (25.84 and 4.53 h), respectively, are noted. In general, essential oil from O. basilicum compounds was readily eliminated, showing promising potential for use as an anesthetic in aquaculture.


Asunto(s)
Monoterpenos Acíclicos , Derivados de Alilbenceno , Anestésicos , Anisoles , Ocimum basilicum , Aceites Volátiles , Animales , Cromatografía de Gases y Espectrometría de Masas/veterinaria , Aceites de Plantas/farmacología , Aceites Volátiles/farmacología , Anestésicos/farmacología
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