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Ruminal tympany (bloat) has long been an issue for large and small livestock operations. Though improvements in feedlot management practices have reduced its occurrence, it is still highly prevalent and is known to detrimentally affect animal performance, welfare, and in many instances, lead to animal death. Current decision support systems and diet formulation software omit the inclusion of bloat prediction based on animal performance. Here, we aim to predict bloat incidence in implanted and non-implanted feedlot steers from performance data comparing linear (LDB) and non-linear decision boundaries. Eighteen crossbred Angus × Hereford steers: BW (491.13 ± 25.78 kg) and age (12 ± 1 mo) were randomly distributed into implanted and non-implanted treatments. All animals were randomly assigned to one of two pens fit with automated monitoring systems for BW, freshwater intake, and water intake behavior: water intake event visit, no water intake event visit (NWIE), and time spent drinking. DM intake (DMI) was individually recorded from all animals through the Calan Gate system for 135 d (30 d adaptation, 105 d experimental diet). Incidences of bloat were recorded as bloat instances regardless of severity to ensure that early onset detection of bloat was recorded and properly identified in predictive models. Logistic regression with a binomial distribution and a logit link function was utilized to predict the incidences of bloat through LDB. Feature selection and penalization of coefficients were explored through L1 (sum of absolute values) and L2 (sum of squares) penalization to avoid overfitting of models. Additional NLDB and a non-parametric LDB are examined for prediction. Accuracy, specificity, and sensitivity were high for the models reported. No significant differences were observed between LDB and NLDB, with the highest specificity (predicting bloat) value of 0.820 for stepwise feature selection algorithms, and a value of 0.832 for the artificial neural network. Highest accuracy was 0.829 for ridge regression, and 0.847 for the random forest with hyperparameter tuning. DM intake, BW, and NWIE were the three most important variables for the prediction of feedlot bloat showing clear drops in DMI and BW and increases in NWIE when animals bloated. The lack of difference in predictive performance between LDB and NLDB highlights the often-overlooked concept that machine learning algorithms are not always the only/best modeling technique. Additionally, the models reported herein carry acceptable predictive performance for inclusion into management decisions that reduce bloat incidences in feedlot cattle.
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Ração Animal , Dieta , Bovinos , Animais , Ração Animal/análise , Dieta/veterinária , Coleta de DadosRESUMO
The influence of manganese modification on the spectroscopic features of manganese-doped CeO2 systems synthesized by the microwave-assisted hydrothermal route and their correlation with the presence of O defective structures were verified, focusing on their interaction with poisonous atmospheres. Raman and electron paramagnetic resonance studies confirmed the presence of defective clusters formed by dipoles and/or quadrupoles. The number of paramagnetic species was found to be inversely proportional to the doping concentration, resulting in an increase in the Mn2+ signal, likely due to the reduction of Mn3+ species after the interaction with CO. X-ray photoelectron spectroscopy data showed the pure system with 33% of its cerium species in the Ce3+ configuration, with an abrupt decrease to 19%, after the first modification with Mn, suggesting that 14% of the Ce3+ species are donating one electron to the Mn2+ ions, thus becoming nonparamagnetic Ce4+ species. On the contrary, 58% of the manganese species remain in the Mn2+ configuration with five unpaired electrons, corroborating the paramagnetic feature of the samples seen in the electron paramagnetic resonance study.
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We present the case of a 41-year-old man with Rapp-Hodgkin syndrome who underwent nasal septum deviation surgery under general anaesthesia. This syndrome is rare, with approximately 70 cases reported worldwide. It is one of a group of ectodermal dysplasia syndromes and results from the aberrant development of ectoderm during fetal development. Some of the clinical features may affect anaesthetic management. The most important considerations are potentially difficult airway management, the need for meticulous temperature control, and the importance of skin protection. This case was uneventful, but as there are few case reports on the management of patients with ectodermal dysplasia syndromes undergoing anaesthesia this report contributes useful knowledge. The pathogenesis and clinical features of Rapp-Hodgkin syndrome and the anaesthetic management for this patient are described.
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BACKGROUND: Neoadjuvant chemotherapy may improve overall survival (OS) in 'borderline' resectable pancreatic cancer (RPC). Whether the results are the same in upfront RPC is unknown. MATERIALS AND METHODS: To evaluate the association of neoadjuvant treatment and survival outcomes in RPC, a systematic literature review was carried out including prospective randomized trials of neoadjuvant treatment versus upfront surgery. Articles indexed in PubMed, Embase and Scopus were evaluated. Data regarding systemic treatment regimens, R0 resection rates, disease-free survival (DFS) and OS were extracted. The outcomes were compared using a random-effects model. The index I2 and the graphs of funnel plot were used for the interpretation of the data. RESULTS: Of 3229 abstracts, 6 randomized controlled trials were considered eligible with a combined sample size of 805 RPC patients. Among the trials, PACT-15, PREP-02/JSAP-05 and updated long-term results from PREOPANC and NEONAX trials were included. Combining the studies with meta-analysis, we could see that neoadjuvant treatment in RPC does not improve DFS [hazard ratio (HR) 0.71 (0.46-1.09)] or OS [HR 0.76 (0.52-1.11)], without significant heterogeneity. Interestingly, R0 rates improved â¼20% with the neoadjuvant approach [HR 1.2 (1.04-1.37)]. It is important to note that most studies evaluated gemcitabine-based regimens in the neoadjuvant setting. CONCLUSIONS: Neoadjuvant chemotherapy or chemoradiation does not improve DFS or OS in RPC compared to upfront surgery followed by adjuvant treatment. Neoadjuvant treatment improves R0 rates by â¼20%. Randomized ongoing trials are eagerly awaited with more active combined regimens including modified FOLFIRINOX.
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Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Terapia Neoadjuvante/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Neoplasias PancreáticasRESUMO
BACKGROUND: The Brazilian federal government issued Ministerial Ordinance No. 718 in 2010 to expand the funding of orthodontic treatment provided by Brazilian municipalities via the Unified Health System (SUS in Portuguese). AIM: To identify social and structural factors associated with Brazilian municipalities that provide fixed orthodontic appliance therapy and interceptive orthodontic therapy. METHODS: Official Brazilian government databases were used for data collection. Poisson regression with robust variance was used for statistical analysis. RESULTS: Municipalities hosting Dental Specialty Centers (DSCs) with greater installed capacity (type III DSC with 7 dental chairs or over), which employed dentists specializing in pediatric dentistry and orthodontics, were more likely to offer orthodontic services via SUS. CONCLUSIONS: Federal, state, and municipal managers need to review the funding of orthodontic services via SUS, which can be used for creating DSCs and hiring professionals with expertise in orthodontics.
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Ortodontia , Criança , Humanos , Brasil , Ortodontia Interceptora , Assistência Odontológica , OdontopediatriaRESUMO
Surface guidance systems enable patient positioning and motion monitoring without using ionising radiation. Surface Guided Radiation Therapy (SGRT) has therefore been widely adopted in radiation therapy in recent years, but guidelines on workflows and specific quality assurance (QA) are lacking. This ESTRO-ACROP guideline aims to give recommendations concerning SGRT roles and responsibilities and highlights common challenges and potential errors. Comprehensive guidelines for procurement, acceptance, commissioning, and QA of SGRT systems installed on computed tomography (CT) simulators, C-arm linacs, closed-bore linacs, and particle therapy treatment systems are presented that will help move to a consensus among SGRT users and facilitate a safe and efficient implementation and clinical application of SGRT.
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Radioterapia Guiada por Imagem , Humanos , Aceleradores de Partículas , Posicionamento do Paciente , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Tomografia Computadorizada por Raios X/métodosRESUMO
Introduction: Surface Guided Radiation Therapy (SGRT) is being increasingly implemented into clinical practice across a number of techniques and irradiation-sites. This technology, which is provided by different vendors, can be used with most simulation- and delivery-systems. However, limited guidelines and the complexity of clinical settings have led to diverse patterns of operation. With the aim to understand current clinical practice a survey was designed focusing on specifics of the clinical implementation and usage. Materials and methods: A 32-question survey covered: type and number of systems, quality assurance (QA), clinical workflows, and identification of strengths/limitations. Respondents from different professional groups and countries were invited to participate. The survey was distributed internationally via ESTRO-membership, social media and vendors. Results: Of the 278 institutions responding, 172 had at least one SGRT-system and 136 use SGRT clinically. Implementation and QA were primarily based on the vendors' recommendations and phantoms. SGRT was mainly implemented in breast RT (116/136), with strong but diverse representation of other sites. Many (58/135) reported at least partial elimination of skin-marks and a third (43/126) used open-masks. The most common imaging protocol reported included the combination of radiographic imaging with SGRT. Patient positioning (115/136), motion management (104/136) and DIBH (99/136) were the main applications.Main barriers to broader application were cost, system integration issues and lack of demonstrated clinical value. A lack of guidelines in terms of QA of the system was highlighted. Conclusions: This overview of the SGRT status has the potential to support users, vendors and organisations in the development of practices, products and guidelines.
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Exploring alternative supplementation sources capable of maximizing feed and water efficiency in nursing Holstein calves is often ignored. The goals herein involve investigating the effects of two isoenergetic supplements on a nonmedicated milk replacer diet on total water intake, milk water intake, fresh water intake, feed intake parameters, and performance of Holstein nursing bull calves. Twenty-three animals (body weight [BW] = 94.67 ± 12.07 kg, age = 67 days old) were randomly assigned to one of three treatments for 68 days: control (CON; ad libitum milk replacer, n = 7), carbohydrate supplement (CHO; corn starch on top of ad libitum milk replacer-based diet, n = 8), or lipid supplement (FAT; menhaden fish oil on top of ad libitum milk replacer-based diet, n = 8). The isoenergetic supplementation consisted of 3% menhaden fish oil addition on DM basis for FAT. This was matched energetically with corn starch for the CHO group resulting in a 7% composition in DM basis. All animals were provided free access to mineral mix and 120 g daily dried microbrewer's spent grains (BG). Data were analyzed with the GLMMIX procedure of SAS in a completely randomized design with the diets as a fixed effect. Dry matter intake (DMI) adjusted by average daily gain (ADG; DMI/ADG) resulted in significantly lower values for supplemented groups with CON = 2.48, CHO = 2.38, and FAT = 2.27 kg/kg (ADG) (P = 0.033). Energy intake values were lower for CON when analyzing metabolizable energy intake (P < 0.0001), net energy intake for maintenance (P < 0.0001), and net energy intake for gain (P < 0.0001), followed by CHO, and then FAT. Total water intake (P < 0.0001), milk water intake (P < 0.0001), and fresh water intake (P < 0.0001) all resulted in CHO consuming 0.5 L or less water than the other two treatments. Energy requirements as digestible energy (P < 0.0001), metabolizable energy (P < 0.0001), net energy for maintenance (P < 0.0001), and net energy for gain (P < 0.0001) were lower for CHO, followed by CON, and then FAT having the highest requirements. Similar results were observed for residual feed (RFI; P = 0.006) and residual water intakes (RTWI; P = 0.902). Ultimately, no performance differences were detected with regards to BW (CON = 146.71, CHO = 146.25, and FAT = 150.48 kg; P > 0.1). These results indicate that lipid-based and starch-based supplementation can potentially increase feed efficiency and decrease voluntary water intake without adversely affecting performance.
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We study the spreading of SARS-CoV-2 in Brazil based on official data available since March 22, 2020. Calculations are done via an adaptive susceptible-infected-removed (SIR) model featuring dynamical recuperation and propagation rates. We are able reproduce the number of confirmed cases over time with less than 5% error and also provide with short- and long-term predictions. The model can also be used to account for the epidemic dynamics in other countries with great accuracy.
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In professional soccer, increasing amounts of data are collected that harness great potential when it comes to analysing tactical behaviour. Unlocking this potential is difficult as big data challenges the data management and analytics methods commonly employed in sports. By joining forces with computer science, solutions to these challenges could be achieved, helping sports science to find new insights, as is happening in other scientific domains. We aim to bring multiple domains together in the context of analysing tactical behaviour in soccer using position tracking data. A systematic literature search for studies employing position tracking data to study tactical behaviour in soccer was conducted in seven electronic databases, resulting in 2338 identified studies and finally the inclusion of 73 papers. Each domain clearly contributes to the analysis of tactical behaviour, albeit in - sometimes radically - different ways. Accordingly, we present a multidisciplinary framework where each domain's contributions to feature construction, modelling and interpretation can be situated. We discuss a set of key challenges concerning the data analytics process, specifically feature construction, spatial and temporal aggregation. Moreover, we discuss how these challenges could be resolved through multidisciplinary collaboration, which is pivotal in unlocking the potential of position tracking data in sports analytics.
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Desempenho Atlético/estatística & dados numéricos , Big Data , Análise de Dados , Futebol/estatística & dados numéricos , Gerenciamento de Dados , Humanos , InformáticaRESUMO
PURPOSE: This study aimed to evaluate parents' perceptions of the oral health status of children enrolled in public preschools and associated factors. METHODS: This was a cross-sectional study with data collected via self-administered questionnaire. A total of 474 questionnaires were distributed in public preschools in the city of Canoas, Rio Grande do Sul, the southernmost state of Brazil. Poisson regression models were used in the multivariate analysis (p < 0.05). RESULTS: The study included 171 (36%) valid questionnaires. The prevalence of parents who perceived the oral health status of their children as negative was 29.8% (n = 51). Mother being unemployed (vs employed) increased by 16% the likelihood of parents perceiving the oral health status of their children as negative (prevalence ratio [PR] 1.16; 95% confidence interval [CI] 1.02-1.31. Parents having (vs having not) observed difficulties in the child's ability to eat increased by 27% the likelihood of perceiving the child's oral health status as negative (PR 1.27; 95% CI 1.08-1.48), while child's tooth brushing 1-2 (vs 3 or more) times a day and family income up to 2 (vs 3 or more) minimum wages increased it by 14% (PR 1.14; 95% CI 1.03-1.27 for both). Current or past use (vs no use) of pacifiers increased by 12% the likelihood of parents' negative perceptions (PR 1.12; 95% CI 1.00-1.25). CONCLUSION: We can conclude that unemployed mothers, low-income families, parents having observed child's feeding difficulties, child's tooth brushing 1-2 times a day, and current or past use of pacifiers contributed significantly to parents' negative perception of the child's oral health status. These factors are essential for the planning, implementation, monitoring, and evaluation of actions aimed at controlling the oral health of children enrolled in public preschools.
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Saúde Bucal , Pais , Brasil/epidemiologia , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Percepção , Inquéritos e QuestionáriosRESUMO
Besides technical and tactical aspects, basketball matches involve high aerobic and anaerobic capacities, conferring the final performance of a team. Thus, the evaluation of physical and technical responses is an effective way to predict the performance of athletes. Field and laboratory tests have been used in sports. The first involving high ecological validity and low cost, and the second, greater control and accuracy but not easy application, considering the different preparation phases in a season. This study aimed, through complex networks analysis, to verify whether centrality parameters analysed from significant correlations behave similarly in distinct scenarios (laboratory and on-court), emphasizing aerobic and anaerobic physical parameters and technical performances. The results showed that, in a compelling analysis involving basketball athletes, the studied centralities (degree, betweenness, eigenvector and pagerank) revealed similar responses in both scenarios, which is widely attractive considering the greater financial economy and lower time when applying tests in the field.
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Taxifolin possesses gastroprotective property but is characterized by low water solubility, is instabile in alkaline medium, and is degraded by the intestinal bacteria flora. The purpose of the work was therefore to produce a gastroadhesive formulation to prolong taxifolin residence time and release in the stomach. We first demonstrated that taxifolin is stable in simulated gastric fluid with or without pepsin and mucus, and is able to cross pig gastric mucus layer and stomach mucosa. Next, gastromucoadhesive microparticles composed of Syloid® AL-1 mesoporous silica, chitosan and HPMC were produced using spray-drying. Microparticles were characterized by a spherical shape and a mean volume-equivalent diameter around 12 µm. The optimized microparticles were able to release taxifolin and to adhere to pig stomach mucosa for 5 h.
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Quitosana/química , Portadores de Fármacos/química , Fármacos Gastrointestinais/química , Quercetina/análogos & derivados , Adesividade , Animais , Liberação Controlada de Fármacos , Excipientes/química , Mucosa Gástrica/metabolismo , Microtecnologia , Mimusops/química , Tamanho da Partícula , Permeabilidade , Quercetina/química , Sementes/química , Dióxido de Silício/química , SuínosRESUMO
Objetivou-se avaliar o efeito de complexos enzimáticos sobre a energia metabolizável e o coeficiente de digestibilidade de nutrientes do milheto para frangos de corte. Quinhentos e setenta e seis frangos machos foram distribuídos em 36 gaiolas, com três tratamentos: T1 - composição de milheto sem complexo enzimático; T2 - composição de milheto com complexo enzimático (CES) e T3 - composição de milheto com complexo enzimático (CEV). Os tratamentos foram definidos com base em seis dietas (três dietas referências e três dietas testes). As dietas testes foram obtidas pela substituição de 40% da dieta referência por milheto inteiro, e a adição de enzimas consistiu de dois complexos enzimáticos: CES, constituído pelas enzimas fitase, protease, xilanase, ß-glucanase, celulase, amilase e pectinase; e CEV. constituído pelas enzimas protease, celulase e amilase. Na fase de 11 a 20 dias, a suplementação com o CEV reduziu os valores de EMA, EMAn e CDPB. A suplementação com CES melhorou o CDPB, e não houve efeito significativo para CDMS e CDEB. Na fase de 21 a 30 dias, houve menor aproveitamento da energia e dos nutrientes com as suplementações CES e CEV. Na fase de 31 a 40 dias, as suplementações reduziram os valores de EMA, EMAn, e o complexo CEV foi efetivo em aumentar o valor de CDPB. A inclusão dos complexos enzimáticos CES (fitase, protease, xilanase, ß-glucanase, celulase, amilase e pectinase) e CEV (protease, celulase e amilase) não favoreceu a utilização da energia do milheto, no entanto melhorou o coeficiente de digestibilidade da proteína do milheto nos períodos de 11 a 20 e de 31 a 40 dias de idade.(AU)
The objective of this study was to evaluate the effect of enzymatic complexes on metabolizable energy and nutrient digestibility coefficient of millet for broilers chickens. 576 male chickens, were distributed in 36 cages with three treatments: T1 - millet composition without enzymatic complex; T2 - millet composition with enzymatic complex (ECS); and T3 - millet composition with enzymatic complex (ECV). The treatments were defined from six diets (3 reference diets and 3 test diets). The test diets were obtained from the substitution of 40% for reference diet by whole millet, and the enzyme addition consisted of two enzymatic complex, ECS constituted by phytase, protease, xylanase, ß-glucanase, cellulase, amylase and pectinase enzymes, and ECV constituted by protease, cellulase and amylase enzymes. In the 11 to 20 days phase, a supplementation with the ECV reduced the AME, AMEn and CDPB values, a ECS supplementation improved the CDPB, and there was no significant effect for CDMS and CDEB. In the 21 to 30 days phase, there were less profit of the energy and nutrients with ECS and ECV supplements. In the 31 to 40 days phase as supplements reduced the values of AME, AMEn, and the ECV complex was effective in increasing the value of CDPB. The inclusion of ECS enzymatic complexes, (phytase, protease, xylanase, ß-glucanase, cellulase, amylase and pectinase) and ECV (protease, cellulase and amylase), did not favor millet's energy utilization, however, favored the millet's protein digestibility coefficient on 11 to 20 and 31 to 40 periods.(AU)
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Animais , Masculino , Galinhas , Enzimas , Milhetes , Ração Animal/análise , DigestãoRESUMO
Cerebral vasospasm (CVS) is a life-threatening condition that occurs in a large proportion of those affected by subarachnoid haemorrhage and stroke. CVS manifests itself as the progressive narrowing of intracranial arteries. It is usually diagnosed using Doppler ultrasound, which quantifies blood velocity changes in the affected vessels, but has low sensitivity when CVS affects the peripheral vasculature. The aim of this study was to identify alternative biomarkers that could be used to diagnose CVS. We used a 1D modelling approach to describe the properties of pulse waves that propagate through the cardiovascular system, which allowed the effects of different types of vasospasm on waveforms to be characterised at several locations within a simulated cerebral network. A sensitivity analysis empowered by the use of a Gaussian process statistical emulator was used to identify waveform features that may have strong correlations with vasospasm. We showed that the minimum rate of velocity change can be much more effective than blood velocity for stratifying typical manifestations of vasospasm and its progression. The results and methodology of this study have the potential not only to improve the diagnosis and monitoring of vasospasm, but also to be used in the diagnosis of many other cardiovascular diseases where cardiovascular waves can be decoded to provide disease characterisation.
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Circulação Cerebrovascular , Modelos Biológicos , Vasoespasmo Intracraniano/fisiopatologia , Benchmarking , Velocidade do Fluxo Sanguíneo , Humanos , Ultrassonografia Doppler Transcraniana , Vasoespasmo Intracraniano/diagnóstico por imagemRESUMO
We study the effects of spatially long-range correlated phase disorder on the Hadamard quantum walk on a line. The shift operator is built to exhibit an intrinsic disorder distribution featuring long-range correlations. To impose such, we resort to fractional Brownian motion with power-law spectrum 1/k^{2α} with α≥0 being the exponent that controls the degree of correlations. We discuss the scaling behavior of the walker's wave packet and report a localization-delocalization transition controlled by α. We unveil two intermediate dynamical regimes between exponential localization and full delocalization.
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AIMS: To determine whether oral antioxidant therapies, of various types and doses, are able to prevent or treat women with preeclampsia. DATA SYNTHESIS: The following databases were searched: MEDLINE, CENTRAL, LILACS, and Web of Science. Inclusion criteria were: a) randomized clinical trials; b) oral antioxidant supplementation; c) study in pregnant women; d) control group, treated or not with placebo. Papers were excluded if they evaluated antioxidant nutrient supplementation associated with other non-antioxidant therapies. Data were extracted and the risk of bias of each study was assessed. Heterogeneity was analyzed using the Cochran Q test, and I2 statistics and pre-specified sensitivity analyses were performed. Meta-analyses were conducted on prevention and treatment studies, separately. The primary outcome was the incidence of preeclampsia in prevention trials, and of perinatal death in treatment trials. Twenty-nine studies were included in the analysis, 19 for prevention and 10 for treatment. The antioxidants used in these studies were vitamins C and E, selenium, l-arginine, allicin, lycopene and coenzyme Q10, none of which showed beneficial effects on the prevention of preeclampsia (RR: 0.89, CI 95%: [0.79-1.02], P = 0.09; I2 = 39%, P = 0.04) and other outcomes. The antioxidants used in the treatment studies were vitamins C and E, N-acetylcysteine, l-arginine, and resveratrol. A beneficial effect was found in intrauterine growth restriction. CONCLUSIONS: Antioxidant therapy had no effects in the prevention of preeclampsia but did show beneficial effects in intrauterine growth restriction, when used in the treatment of this condition.
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Anti-Hipertensivos/administração & dosagem , Antioxidantes/administração & dosagem , Pressão Sanguínea/efeitos dos fármacos , Pré-Eclâmpsia/tratamento farmacológico , Pré-Eclâmpsia/prevenção & controle , Administração Oral , Adolescente , Adulto , Anti-Hipertensivos/efeitos adversos , Antioxidantes/efeitos adversos , Medicina Baseada em Evidências , Feminino , Retardo do Crescimento Fetal/prevenção & controle , Humanos , Incidência , Pré-Eclâmpsia/mortalidade , Pré-Eclâmpsia/fisiopatologia , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Resultado do Tratamento , Adulto JovemRESUMO
Molecularly imprinted polymers are advanced recognition materials selectively rebinding a target molecule present during the synthesis of the polymer matrix. It is commonly understood that the templating process is based on embedding the complex formed between a template and functional monomers into a co-polymer matrix. This happens by a polymerization of the complex with a cross-linker while maintaining their spatial arrangement forming a molecular imprint. Template removal then leads to synthetic recognition sites ready to selectively rebind their targets, which are complementary in functionality, size and shape to the target. In this study, an innovative theoretical concept using fully atomistic molecular dynamics simulations for modeling molecular templating processes is introduced yielding virtually imprinted polymers (VIPs). VIPs created for the template 17-ß-estradiol and applied in modeled chromatography experiments demonstrated selectivity for their template. This evidenced the creation of virtual imprints as a result of a templated synthesis protocol, which represents a theoretical confirmation of the governing imprinting theory.
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Synthetic molecular recognition materials, such as molecularly imprinted polymers (MIPs), are of increasing importance in biotechnology and analytical chemistry, as they are able to selectively bind their respective template. However, due to their specificity, each MIP has to be individually designed for the desired target leading to a molecularly tailored synthesis strategy. While trial-and-error remains the common approach for selecting suitable functional monomers (FMs), the study herein introduces a radically new approach towards rationally designing MIPs by rapidly screening suitable functional monomers based on local density of states (LDOS) calculations in a technique known as Electronic Indices Methodology (EIM). An EIM-based method of classification of FMs according to their suitability for imprinting was developed. Starting from a training set of nine different functional monomers, the prediction of suitability of four functional monomers was possible. These predictions were subsequently experimentally confirmed.
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This study investigated individual and combined effects of organic acids, bacteriophages, and ultraviolet light interventions on Salmonella populations in ground beef. Beef trim was inoculated with four Salmonella strains to result in a contamination level of 3.5 log CFU/g after grinding. Lactic (LA) and peroxyacetic (PAA) acids, bacteriophages (S16 and FO1a) (BA), and ultraviolet light (UV) were applied on fresh trim prior to grinding. Applications of individual or combined organic acids did not significantly decrease Salmonella populations in ground beef. Individual applications of BA and UV light decreased approximately 1 log CFU/g (P<0.05). Combined applications of BA and UV provided an optimal decrease of 2 log CFU/g (P<0.05). Organic acid applications do not reduce Salmonella populations in ground beef when applied on trim prior to grinding. Combined applications of UV and BA may be used in industry settings to improve Salmonella control in ground beef.