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1.
Prev Vet Med ; 233: 106352, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39357131

RESUMO

There is increasing pressure to reduce and refine antimicrobial use (AMU) in farmed livestock, to slow the development of antimicrobial resistance (AMR) and preserve the efficacy of antimicrobials (AMs) in both humans and animals. Developing strategies to help drive the prudent use of AMs requires an understanding of the direct and indirect factors influencing the between-farm variation in AMU typically observed. Given limited evidence of risk factors in sheep, this exploratory study aimed to investigate whether sheep flocks could be classified into farm types based on farm characteristics, health parameters and management practices, and whether important differences existed in AMU between these flock types. This study was conducted on 22 sheep flocks in Wales, United Kingdom as part of a wider longitudinal study on AMU and AMR. Comprehensive surveys were administered to flocks where 147 variables regarding farm characteristics, flock health parameters and management practices were captured. AMU data for each flock were also collated. A Multiple Correspondence Analysis (MCA), followed by a Hierarchical Clustering on Principal Components (HCPC) analysis, were used to classify the flocks. The top 10 dimensions yielded by MCA explained 67.4 % of the total variance. Nine partitions of relatively homogeneous flocks, derived from three typologies produced from the first three cut-points of the HCPC dendrogram, were visualised and described. These nine partitions were characterised by 70 variable categories, principally the implementation or neglect of best-practice lameness management practices. Partitions of flocks that neglected best-practice lameness managements - characterised by delayed treatments of lame sheep, footbathing and bleeding when foot trimming - reported higher lameness prevalence and fewer lame ewes recovering within five days of treatment. These flocks had higher total AMU (mg/PCU) and used a higher mass of injectable AMs than other partitions of flocks. Flock traits, lambing practices, disease challenges and other management factors also described partitions derived in later dendrogram cuts. Findings from this study confirm good AM stewardship in sheep flocks to be a complex picture, given the typologies of flocks described and the range of factors likely to influence AMU. Opportunities for targeted strategies for sustainable reductions in AMU can be directed towards specific flock types identified, specifically within the context of lameness treatment and control. We highlight the importance of understanding flock heterogeneity, through the construction of typologies, as a means to fine-tune appropriate interventions to specific flock types in order to help drive more prudent use of AMs.

2.
Stat Med ; 2024 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-39370732

RESUMO

Mendelian randomization is an instrumental variable method that utilizes genetic information to investigate the causal effect of a modifiable exposure on an outcome. In most cases, the exposure changes over time. Understanding the time-varying causal effect of the exposure can yield detailed insights into mechanistic effects and the potential impact of public health interventions. Recently, a growing number of Mendelian randomization studies have attempted to explore time-varying causal effects. However, the proposed approaches oversimplify temporal information and rely on overly restrictive structural assumptions, limiting their reliability in addressing time-varying causal problems. This article considers a novel approach to estimate time-varying effects through continuous-time modelling by combining functional principal component analysis and weak-instrument-robust techniques. Our method effectively utilizes available data without making strong structural assumptions and can be applied in general settings where the exposure measurements occur at different timepoints for different individuals. We demonstrate through simulations that our proposed method performs well in estimating time-varying effects and provides reliable inference when the time-varying effect form is correctly specified. The method could theoretically be used to estimate arbitrarily complex time-varying effects. However, there is a trade-off between model complexity and instrument strength. Estimating complex time-varying effects requires instruments that are unrealistically strong. We illustrate the application of this method in a case study examining the time-varying effects of systolic blood pressure on urea levels.

3.
Nat Prod Res ; : 1-7, 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39340340

RESUMO

Ginger (Zingiber officinale), a globally distributed plant, is widely used in the industry for its flavourings, seasonings, and beverages. However, maintaining its quality and volatile components during processing has posed a challenge. This study, therefore, aimed to assess the impact of drying time (24, 48, and 72h) in a circulation oven at 40 °C on the chemical composition and yield of fresh and dried ginger. The essential oils were extracted using the hydrodistillation method, and their chemical analysis was conducted using gas chromatography. The drying time in the oven directly influenced the essential oil yield, with a longer time resulting in a higher yield. We identified 27 compounds in the essential oils, varying their predominance depending on the drying time. The PCA analysis revealed that the drying time can lead to the formation of different chemotypes for ginger, indicating that altering the drying time can yield significantly different chemical profiles.

4.
Aten Primaria ; 57(2): 103075, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39288729

RESUMO

OBJECTIVE: To assess the association between dietary patterns and glycemic control among patients with type II diabetes mellitus (T2DM). DESIGN: A cross-sectional study. SITE: The 2015-2018 National Health and Nutrition Examination Survey (NHANES). PARTICIPANTS: A total of 1646 T2DM patients were included, of whom 854 were hyperglycemia. METHODS: Main dietary patterns were identified using the sparse principal components analysis (SPCA). Logistic regression analysis was applied to investigate the association between each dietary pattern and the risk of hyperglycemia with odds ratios (OR) and 95% confidence intervals (CI). SPCA analysis yielded five significant principal components (PC), which represented five main dietary patterns. RESULTS: PC1, characterized by a high intake of sweets, red meat and processed meat, was associated with higher odds of hyperglycemia in patients who underwent hyperglycemic drug or insulin treatments (OR: 1.71, 95% CI: 1.10-2.64). PC5, characterized by high in red meat, while low in coffee, sweets, and high-fat dairy consumption. The relationship between the PC5 and hyperglycemia was marginal significance (OR: 0.63, 95% CI: 0.38-1.02). PC2 was characterized by a high consumption of green vegetables, other vegetables, and whole grains, and low intake of potatoes and processed meat. In patients with the hyperglycemic drug and insulin free, higher PC2 levels were related to lower odds of hyperglycemia (OR: 0.45, 95% CI: 0.21-0.96). CONCLUSIONS: High intake of sweets, red meat, and processed meat might be detrimental to glycemic control in patients with drug-treated T2DM. High in red meat, while low in coffee, sweets, and high-fat dairy consumption may be beneficial to glycemic control. In addition, high consumption of green vegetables, other vegetables, and whole grains, and low intake of potatoes and processed meat may be good for glycemic control in patients without drug-treated T2DM.

5.
Res Sq ; 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39315263

RESUMO

Background: Metabolic syndrome (MetS), a cluster of metabolic dysregulations indicative of increased cardiometabolic risk is on the rise in Sub-Saharan Africa. The study aimed to determine the prevalence of MetS and its components, among corporate employees in Kampala, Uganda. Methods: A cross-sectional survey was undertaken among 408 adults who were employees from seven corporate companies in Kampala, using the WHO STEPwise NCD screening approach. Metabolic syndrome was measured using the National Cholesterol Education Program Adult Treatment Panel (ATPIII) and the International Diabetes Federation (IDF) criteria with the waist circumference (WC) cut-off points adapted for Sub-Saharan African populations. Results: The mean population age (standard deviation [SD]) of the respondents was 34years (± 8.87) years and 52% of them were females. The prevalence of MetS was 22.8% (NCEP ATPIII) and 28.4% (IDF). Of the respondents who did not have MetS, 75% had at least one metabolic dysregulation. Of those respondents with MetS, only 31% perceived that they were at risk of this cluster of metabolic dysregulations. In this analysis, we observed that the systolic blood pressure (BP) and the body mass index (BMI) correlated strongly (r = 0.81 and r = 0.71) with the diastolic BP and waist circumference (WC), respectively. Age on the other hand correlated fairly with the WC and BMI (both r values = 0.46). Principal component analysis showed that the greatest loadings in principle factors one, two and three were from central obesity, with low HDL-C explaining 60.8% variance in the population. Age, BMI, family history of having cardiometabolic disorders, and perceived cardiometabolic disease risk (CMR) were associated with an increased risk of MetS by 5, 8.86, 1.55, and 2.73 (all P values were < 0.05) respectively in this group of respondents. These risks remained for age, BMI and perceived CMR after removing the confounding effects of education status, marital status and family history of cardiometabolic disease. Being single on the other hand, was associated with a reduced risk of MetS (0.23, p < 0.009). Conclusion: While the primary contributors to the high prevalence of MetS among corporate employees in Kampala, Uganda were the high BP, high WC and high fasting blood sugar (FBS); age, BMI and perceived CMR were the key determinants of MetS. Future MetS interventions should aim to control and monitor obesity indicators in this population. Additionally, the findings inform targeted screening parameters for cardiometabolic risk assessment and suggest the need for further research into a weighted algorithm for MetS in this population.

6.
Cureus ; 16(8): e66602, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39258036

RESUMO

Introduction  The Verbal Behavior Milestones Assessment and Placement Program (VB-MAPP) is an extensive tool used to assess children with autism and other developmental disabilities who have language delays. Applied behavior analysis (ABA) professionals frequently use the VB-MAPP to create personalized intervention programs catering to each child's needs. The lack of studies examining the VB-MAPP at the pretest, posttest, and differential scores using principal components analysis (PCA) suggests an opportunity to conduct PCAs on these different VB-MAPP scores. In doing so, researchers could better understand the VB-MAPP's dimensionality and factor structure at these levels. This, in turn, could inform the development of more effective assessment strategies and intervention plans for individuals with language and social communication challenges.  Materials and methods From January 2018 to July 2021, The Oxford Center in Brighton and Troy, Michigan, treated autistic children using ABA therapy. A convenience sample of 13 children was retrospectively analyzed using VB-MAPP, which evaluates various behavioral milestones using a pretest-posttest design. Descriptive data analysis and internal consistency reliability estimates (using Cronbach's alpha) were calculated for pretest, posttest, and difference scores. A Wilcoxen signed-rank test was conducted to determine the statistical significance between the pretest and posttest. Correlation matrices were inspected for relevant relationships between VB-MAPP scales, and a PCA with orthogonal rotation was also performed on this pretest, posttest, and difference scores. Results The mean age for the children was 4.083 years ± 1.083 years, (95%CI 3.64, 4.36). Around 66.6% of the children had an autism severity level of three, 33.3% had a severity level of two, and none were at level one. Cronbach's alpha for internal consistency reliability of the pretest, posttest, and difference scores, indicating excellent reliability with values of 0.948 for the pretest and 0.937 for the posttest, respectively. The difference scores had a lower but acceptable reliability coefficient of 0.752. PCA on the pretest scores identified three factors that explain 85.584% of the total variation, indicating that these components capture most of the data's structure. The posttest PCA also identified three factors, accounting for 84.293% of the variance, suggesting a similar complexity and good model fit as the pretest. PCA revealed four factors explaining 82.317% of the variation for the difference scores. The increase in factors suggests that changes between pretest and posttest scores are complex, likely due to the ABA treatment, and require an additional component to represent the data adequately. There is a good model fit; the underlying structure is more complex than the pretest or posttest alone. Conclusions Robust coefficient alphas combined with the shift to a more detailed factor structure post-ABA treatment highlight ABA therapy's diverse and multi-faceted impact on children. The increase from three to four principal components indicates a richer and more nuanced pattern of improvements across different domains of verbal and social behavior. This detailed factor structure is a testament to the comprehensive and individualized nature of ABA treatment, reflecting the therapy's effectiveness in addressing specific needs and fostering broad developmental gains in children.

7.
J Physiol ; 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39234878

RESUMO

Physiologists often express the change in the value of a measurement made on two occasions as a ratio of the initial value. This is usually motivated by an assumption that the absolute change fails to capture the true extent of the alteration that has occurred in attaining the final value - if there is initial variation among individual cases. While it may appear reasonable to use ratios to standardize the magnitude of change in this way, the perils of doing so have been widely documented. Ratios frequently have intractable statistical properties, both when taken in isolation and when analysed using techniques such as regression. A new method of computing a standardized metric of change, based on principal components analysis (PCA), is described. It exploits the collinearity within sets of initial, absolute change and final values. When these sets define variables subjected to PCA, the standardized measure of change is obtained as the product of the loading of absolute change onto the first principal component (PC1) and the eigenvalue of PC1. It is demonstrated that a sample drawn from a population of these standardized measures: approximates a normal distribution (unlike the corresponding ratios); lies within the same range; and preserves the rank order of the ratios. It is also shown that this method can be used to express the magnitude of a physiological response in an experimental condition relative to that obtained in a control condition. KEY POINTS: The intractable statistical properties of ratios and the perils of using ratios to standardize the magnitude of change are well known. A new method of computing a standardized metric, based on principal components analysis (PCA), is described, which exploits the collinearity within sets of initial, absolute change and final values. A sample drawn from a population of these PCA-derived measures: approximates a normal distribution (unlike the corresponding ratios); lies within the same range as the ratios; and preserves the rank order of the ratios. The method can also be applied to express the magnitude of a physiological response in an experimental condition relative to a control condition.

8.
Talanta ; 279: 126608, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39094530

RESUMO

The presence of fluoroquinolones (FQs) residues in food and the environment has prompted concerns regarding food safety and public health. Consequently, it is of great significance to analyze the types and levels of FQs present. However, the majority of studies have concentrated on the specific detection of individual FQs, with a notable absence of high-throughput and rapid analysis methods for the simultaneous detection of multiple FQs that may coexist in food and the environment. Hereon, a triple-channel sensor array was successfully constructed utilizing fluorescent carbon dots (TA-CDs), with the assistance of Cu2+ and Fe3+, for the qualitative discrimination and quantitative detection of eight types of FQs. The sensor array can distinguish between different concentrations of FQs and various mixtures of FQs, as well as 100 % accuracy in the discrimination of unknown samples. Impressively, the sensor platform can quantitatively detect FQs in animal-derived foods, such as honey, milk, eggs, and pork, as well as in water samples. This research has the potential to be extended to other analytes with similar chemical structures or properties.


Assuntos
Carbono , Corantes Fluorescentes , Fluoroquinolonas , Leite , Pontos Quânticos , Carbono/química , Fluoroquinolonas/análise , Pontos Quânticos/química , Animais , Leite/química , Corantes Fluorescentes/química , Contaminação de Alimentos/análise , Mel/análise , Espectrometria de Fluorescência/métodos , Cobre/química , Cobre/análise , Ovos/análise , Limite de Detecção , Suínos
9.
Entropy (Basel) ; 26(8)2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39202181

RESUMO

A method is proposed for analyzing the tremor of the earth's surface, measured by GPS, in order to highlight prognostic effects. The method is applied to the analysis of daily time series of vertical displacements in Japan. The network of 1047 stations is divided into 15 clusters. The Huang Empirical Mode Decomposition (EMD) is applied to the time series of the principal components from the clusters, with subsequent calculation of instantaneous amplitudes using the Hilbert transform. To ensure the stability of estimates of the waveforms of the EMD decomposition, 1000 independent additive realizations of white noise of limited amplitude were averaged before the Hilbert transform. Using a parametric model of the intensities of point processes, we analyze the connections between the instants of sequences of times of the largest local maxima of instantaneous amplitudes, averaged over the number of clusters and the times of earthquakes in the vicinity of Japan with minimum magnitude thresholds of 5.5 for the time interval 2012-2023. It is shown that the sequence of the largest local maxima of instantaneous amplitudes significantly more often precedes the moments of time of earthquakes (roughly speaking, has an "influence") than the reverse "influence" of earthquakes on the maxima of amplitudes.

10.
One Health ; 19: 100852, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39129789

RESUMO

Highly pathogenic avian influenza (HPAI) is an important zoonotic disease. The study aims to identify farmer behaviour types to inform the design of behaviour change programmes for mitigating the transmission of HPAI. Therefore, the study utilised multivariate statistical analysis for gaining a better understanding of the relationships among farmers' 30 biosecurity behaviours, the risk of HPAI infection, and distinct features of commercial broiler farmers, which is different from using simple and few binary biosecurity measures. Convenience sampling was used to collect data from 303 Taiwan's farmers among which 40 farmers (13.2%) self-reported having had a HPAI outbreak in the study year while 16 farmers (5.3%) self-reported having had a HPAI outbreak in the past two years. Using categorical principal components analysis and a two-stage cluster analysis, four farmer clusters were identified with distinct features: 1)'Reserved' (4.6%) tended to choose 'No idea' for answering specific questions about HPAI; 2)'Secure' (76.3%) had a higher biosecurity status than the other farms; 3) 'Jeopardised' (16.8%) had a lower biosecurity status than the other farms; 4) 'No-response' (2.3%) tended to skip specific questions about HPAI. The biosecurity status of the 'Reserved' and 'No-response' clusters was undetermined, placing these farms at risk of HPAI infection. Compared to the 'Secure' cluster, the 'Jeopardised' cluster exhibited higher odds of self-reported HPAI in the study year (OR: 2.61, 95% CI: 1.22-5.58) and in the past two years (OR: 4.28, 95% CI: 1.39-13.19). Additionally, the 'Jeopardised' cluster showed increased odds of HPAI recurrence (OR: 4.01, 95% CI: 1.41-11.43). Our study demonstrates that inadequate biosecurity practices can elevate the occurrence or recurrence of HPAI outbreaks. The findings underscore the importance of distinguishing between these clusters to accurately assess the risk of HPAI infection across farms. Furthermore, understanding farmers' behaviours can inform the development of strategies aimed at behaviour change among farmers.

11.
Psychon Bull Rev ; 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39174751

RESUMO

Osgood, Suci, and Tannebaum were the first to attempt to identify the principal components of semantics using dimensional reduction of a high-dimensional model of semantics constructed from human judgments of word relatedness. Modern word-embedding models analyze patterns of words to construct higher dimensional models of semantics that can be similarly subjected to dimensional reduction. Hollis and Westbury characterized the first eight principal components (PCs) of a word-embedding model by correlating them with several well-known lexical measures, such as logged word frequency, age of acquisition, valence, arousal, dominance, and concreteness. The results show some clear differentiation of interpretation between the PCs. Here, we extend this work by analyzing a larger word-embedding matrix using semantic measures initially derived from subjective inspection of the PCs. We then use quantitative analysis to confirm the utility of these subjective measures for predicting PC values and cross-validate them on two word-embedding matrices developed on distinct corpora. Several semantic and word class measures are strongly predictive of early PC values, including first-person and second-person verbs, personal relevance of abstract and concrete words, affect terms, and names of places and people. The predictors of the lowest magnitude PCs generalized well to word-embedding matrices constructed from separate corpora, including matrices constructed using different word-embedding methods. The predictive categories we describe are consistent with Wittgenstein's argument that an autonomous level of social interaction grounds linguistic meaning.

12.
Artigo em Inglês | MEDLINE | ID: mdl-39131198

RESUMO

Objective: Although driving simulators are powerful tools capable of measuring a wide-ranging set of tactical and operational level driving behaviors, comparing these behaviors across studies is problematic because there is no core set of driving variables to report when assessing driving behavior in simulated driving scenarios. To facilitate comparisons across studies, researchers need consistency in how driving simulator variables combine to assess driving behavior. With inter-study consistency, driving simulator research could support stronger conclusions about safe driving behaviors and more reliably identify future driver training goals. The purpose of the current study was to derive empirically and theoretically meaningful composite scores from driving behaviors of young people in a driving simulator, utilizing driving data from across a variety of driving environments and from within the individual driving environments. Method: One hundred ninety adolescent participants aged 16 years or 18 years at enrollment provided demographic data and drove in a high-fidelity driving simulator. The simulated scenario included 4 distinct environments: Urban, Freeway, Residential, and a Car Following Task (CFT). A Principal Components Analysis (PCA) was conducted on the variable output from the driving simulator to select optimal factor solutions and loadings both across the multi-environmental drive and within the four individual driving environments. Results: The PCA suggested two components from the multi-environmental simulated drive: vehicle control and speed. The individual driving environments also indicated two components: vehicle control and tactical judgment. Conclusion: These findings are among the first steps for identifying composite driving simulator variables to quantify theoretical conceptualizations of driving behavior. Currently, driving behavior and performance measured by driving simulators lack "gold standards" via driving scores or benchmarks. The composites derived in this analysis may be studied for further use where driving behavior standards are increasingly sought by clinicians and practitioners for a variety of populations, as well as by parents concerned about the readiness of their novice driving teen.

13.
BMC Microbiol ; 24(1): 293, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107684

RESUMO

There is an enormous diversity of life forms present in the extremely intricate marine environment. The growth and development of seaweeds in this particular environment are controlled by the bacteria that settle on their surfaces and generate a diverse range of inorganic and organic chemicals. The purpose of this work was to identify epiphytic and endophytic bacterial populations associated with ten common marine macroalgae from various areas along the Mediterranean Sea coast in Alexandria. This was done to target their distribution and possible functional aspects. Examine the effects of the algal habitat on the counting and phenotypic characterization of bacteria, which involves grouping bacteria based on characteristics such as shape, colour, mucoid nature, type of Gram stain, and their ability to generate spores. Furthermore, studying the physiological traits of the isolates under exploration provides insight into the optimum environmental circumstances for bacteria associated with the formation of algae. The majority of the bacterial isolates exhibited a wide range of enzyme activities, with cellulase, alginase, and caseinase being the most prevalent, according to the data. Nevertheless, 26% of the isolates displayed amylolytic activity, while certain isolates from Miami, Eastern Harbor, and Montaza lacked catalase activity. Geographical variations with the addition of algal extract may impact on the enumeration of the bacterial population, and this might have a relationship with host phylogeny. The most significant observation was that endophytic bacteria associated with green algae increased in all sites, while those associated with red algae increased in Abu Qir and Miami sites and decreased in Eastern Harbor. At the species level, the addition of algal extract led to a ninefold increase in the estimated number of epiphytic bacteria for Cladophora pellucida in Montaza. Notably, after adding algal extract, the number of presented endophytic bacteria associated with Codium sp. increased in Abu Qir while decreasing with the same species in Montaza. In addition to having the most different varieties of algae, Abu Qir has the most different bacterial isolates.


Assuntos
Bactérias , Endófitos , Filogenia , RNA Ribossômico 16S , Alga Marinha , Bactérias/classificação , Bactérias/isolamento & purificação , Bactérias/genética , Egito , Alga Marinha/microbiologia , Endófitos/classificação , Endófitos/isolamento & purificação , Endófitos/genética , Endófitos/fisiologia , Mar Mediterrâneo , RNA Ribossômico 16S/genética , Biodiversidade , Água do Mar/microbiologia , DNA Bacteriano/genética , Ecossistema
14.
Drug Alcohol Depend ; 263: 112421, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39208693

RESUMO

BACKGROUND: Detecting and responding to errors is central to goal-directed behavior and cognitive control and is thought to be supported by a network of structures that includes the anterior cingulate cortex and anterior insula. Sex differences in the maturational timing of cognitive control systems create differential periods of vulnerability for psychiatric conditions, such as substance use disorders. METHODS: We examined sex differences in error-related activation across an array of distributed brain regions during a Go/No-Go task in young adults with problem alcohol use (N=69; 34 females; M=19.4 years). Regions of interest previously linked to error-related activation, including anterior cingulate cortex, insula, and frontoparietal structures, were selected in a term-based meta-analysis. Individual differences in their responses to false alarm (FA) inhibitory errors relative to "go" trials (FA>GO) and correct rejections (FA>CR) were indexed using multivariate summary measures derived from principal components analysis. RESULTS: FA>GO and FA>CR activation both revealed a first component that explained the majority of the variance across error-associated regions and displayed the strongest loadings on salience network structures. Compared to females, males exhibited significantly higher levels of the FA>GO component but not the FA>CR component. CONCLUSIONS: Males exhibit greater salience network activation in response to inhibitory errors, which could be attributed to sex differences in error-monitoring processes or to other functions (e.g., novelty detection). The findings are relevant for the further characterization of sex differences in cognitive control and may have implications for understanding individual differences in those at risk for substance use or other cognitive control disorders.


Assuntos
Imageamento por Ressonância Magnética , Caracteres Sexuais , Humanos , Masculino , Feminino , Adulto Jovem , Alcoolismo/fisiopatologia , Adolescente , Encéfalo/fisiologia , Adulto , Inibição Psicológica , Giro do Cíngulo/fisiologia , Mapeamento Encefálico
15.
J Texture Stud ; 55(4): e12857, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39107967

RESUMO

The tribological properties of 19 commercial food products, grouped into six categories (yogurt, dressings, spreads, porridges, emulsified sauces, and syrups) were investigated in relation to their rheological (dynamic oscillatory shear test) and nutritional properties (fat, carbohydrate, and protein). A tribological system (a glass ball and three polydimethylsiloxane pins) generated the extended Stribeck curve, monitoring friction factors (f) over an extended range of sliding speed (v) (10-8 to 100 m/s). Tribological parameters (f, v) at four inflection points dividing the frictional regimes (X1, breakaway point between the static and kinetic regimes; X1-X2, boundary; X2-X3, mixed; X3-X4, hydrodynamic regimes) and the slope between X3 and X4 (s) were subjected to principal component analysis and hierarchical clustering on principal components, using rheological and nutritional parameters as quantitative supplementary variables. Tribological patterns were predominantly influenced by viscosity, viscoelasticity, yield stress, fat content, and the presence of particles (e.g., sugar, proteins, and fibers) and pasting materials (e.g., starches and modified starches). The 19 tribological patterns were classified into 3 clusters: low f and s for fat- and/or viscoelastic-dominant foods (Cluster 1), low f and high s for food emulsions and/or those with low extent of shear-thinning (Cluster 2), and high f at the boundary regime either for the most viscous foods or for those in the presence of particulates (Cluster 3). These results suggest that the compositional and rheological properties have a more profound impact on the classification of complex tribological patterns than the categories of food products.


Assuntos
Valor Nutritivo , Reologia , Viscosidade , Elasticidade , Alimentos , Fricção , Análise de Alimentos , Análise de Componente Principal
16.
J Chromatogr A ; 1731: 465127, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39053256

RESUMO

Reversed-phase (RP) liquid chromatography is an important tool for the characterization of materials and products in the pharmaceutical industry. Method development is still challenging in this application space, particularly when dealing with closely-related compounds. Models of chromatographic selectivity are useful for predicting which columns out of the hundreds that are available are likely to have very similar, or different, selectivity for the application at hand. The hydrophobic subtraction model (HSM1) has been widely employed for this purpose; the column database for this model currently stands at 750 columns. In previous work we explored a refinement of the original HSM1 (HSM2) and found that increasing the size of the dataset used to train the model dramatically reduced the number of gross errors in predictions of selectivity made using the model. In this paper we describe further work in this direction (HSM3), this time based on a much larger solute set (1014 solute/stationary phase combinations) containing selectivities for compounds covering a broader range of physicochemical properties compared to HSM1. The molecular weight range was doubled, and the range of the logarithm of the octanol/water partition coefficients was increased slightly. The number of active pharmaceutical ingredients and related synthetic intermediates and impurities was increased from four to 28, and ten pairs of closely related structures (e.g., geometric and cis-/trans- isomers) were included. The HSM3 model is based on retention measurements for 75 compounds using 13 RP stationary phases and a mobile phase of 40/60 acetonitrile/25 mM ammonium formate buffer at pH 3.2. This data-driven model produced predictions of ln α (chromatographic selectivity using ethylbenzene as the reference compound) with average absolute errors of approximately 0.033, which corresponds to errors in α of about 3 %. In some cases, the prediction of the trans-/cis- selectivities for positional and geometric isomers was relatively accurate, and the driving forces for the observed selectivity could be inferred by examination of the relative magnitudes of the terms in the HSM3 model. For some geometric isomer pairs the interactions mainly responsible for the observed selectivities could not be rationalized due to large uncertainties for particular terms in the model. This suggests that more work is needed in the future to explore other HSM-type models and continue expanding the training dataset in order to continue improving the predictive accuracy of these models. Additionally, we release with this paper a much larger data set (43,329 total retention measurements) at multiple mobile phase compositions, to enable other researchers to pursue their own lines of inquiry related to RP selectivity.


Assuntos
Cromatografia de Fase Reversa , Interações Hidrofóbicas e Hidrofílicas , Cromatografia de Fase Reversa/métodos , Isomerismo , Preparações Farmacêuticas/química , Preparações Farmacêuticas/análise , Modelos Químicos , Peso Molecular , Água/química
17.
Vet J ; 306: 106194, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38986926

RESUMO

In order to determine an effective procedure for explaining ram sperm cryoresistance and develop a new model for breeders classification, a retrospective study was conducted using sperm analysis data obtained over two consecutive years from a total of 82 sessions of ram semen cryopreservation. In each session, fresh ejaculates from eight males were collected via artificial vagina, pooled and frozen in liquid nitrogen vapors. After thawing, a total of 19,084 sperm tracks and 11,319 morphometric measurements were analysed. Clustering analyses were applied to establish motile and morphometric sperm subpopulations. Additionally, plasma and acrosome membrane integrity, as well mitochondrial activity using flow cytometry immediately after sperm thawing and following hypoosmotic shock test (HOST) was assessed. To develop a Ram Sperm Cryoresistance Index, Principal Component Analyses (PCA) using 22 variables were conducted. In the first PCA, the parameters that best explain cryoresistance include total motility (TM), motile subpopulation 2 (motSP2, which groups slow, very linear spermatozoa with low lateral head displacement), morphometric subpopulation 1 (morphSP1, grouping spermatozoa with the smallest head size and lowest shape values), sperm plasma membrane integrity immediately after thawing and following hypoosmotic shock test. These parameters collectively account for 77.34 % of the accumulated variance. To emphasize their importance, a second PCA was performed, revealing significant higher weighting coefficients for the quantity (TM) and quality (motSP2) of sperm movement after thawing, compared to the head size and shape of the thawed sperm (morphSP1). Furthermore, HOST Viability played a more decisive role than what was observed under isotonic conditions.


Assuntos
Criopreservação , Análise do Sêmen , Preservação do Sêmen , Espermatozoides , Masculino , Animais , Criopreservação/veterinária , Espermatozoides/fisiologia , Ovinos/fisiologia , Preservação do Sêmen/veterinária , Análise do Sêmen/veterinária , Estudos Retrospectivos , Motilidade dos Espermatozoides , Sêmen/fisiologia
18.
BMC Emerg Med ; 24(1): 131, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39075340

RESUMO

BACKGROUND: The process of transferring patients from small rural primary care facilities to referral facilities impacts the quality of care and effectiveness of the referral healthcare system. The study aimed to develop and evaluate the psychometric properties of a scale measuring requirements for effective rural emergency transfer. METHODS: An exploratory sequential design was utilized to develop a scale designed to measure requirements for effective emergency transport. Phase one included a qualitative, interview study with 26 nursing transport providers. These transcripts were coded, and items developed for the proposed scale. Phase two included a content validity review by these 16 transport providers of the domains and items developed. Phase three included development and evaluation of psychometric properties of a scale designed to measure requirements for effective emergency transport. This scale was then tested initially with 84 items and later reduced to a final set of 58 items after completion by 302 transport nurses. The final scale demonstrated three factors (technology & tools; knowledge & skills; and organization). Each factor and the total score reported excellent scale reliability. RESULTS: The initial item pool consisted of 84 items, generated, and synthesized from an extensive literature review and the qualitative descriptive study exploring nurses' experiences in rural emergency patient transportation. A two-round modified Delphi method with experts generated a scale consisting of 58 items. A cross-sectional study design was used with 302 nurses in rural clinics and health in four rural health districts. A categorical principal components analysis identified three components explaining 63.35% of the total variance. The three factors, technology, tools, personal knowledge and skills, and organization, accounted for 27.32%, 18.15 and 17.88% of the total variance, respectively. The reliability of the three factors, as determined by the Categorical Principal Component Analysis (CATPCA)'s default calculation of the Cronbach Alpha, was 0.960, 0.946, and 0.956, respectively. The RET Cronbach alpha was 0.980. CONCLUSIONS: The study offers a three-factor scale to measure the effectiveness of emergency patient transport in rural facilities to better understand and improve care during emergency patient transport.


Assuntos
Transferência de Pacientes , Psicometria , Serviços de Saúde Rural , Humanos , Transferência de Pacientes/normas , Serviços de Saúde Rural/organização & administração , Serviços de Saúde Rural/normas , Reprodutibilidade dos Testes , Feminino , Masculino , Transporte de Pacientes , Adulto , Inquéritos e Questionários/normas , Pesquisa Qualitativa , Pessoa de Meia-Idade
19.
J Appl Stat ; 51(10): 2025-2038, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39071246

RESUMO

Recently, two-way or longitudinal functional data analysis has attracted much attention in many fields. However, little is known on how to appropriately characterize the association between two-way functional predictor and scalar response. Motivated by a mortality study, in this paper, we propose a novel two-way functional linear model, where the response is a scalar and functional predictor is two-way trajectory. The model is intuitive, interpretable and naturally captures relationship between each way of two-way functional predictor and scalar-type response. Further, we develop a new estimation method to estimate the regression functions in the framework of weak separability. The main technical tools for the construction of the regression functions are product functional principal component analysis and iterative least square procedure. The solid performance of our method is demonstrated in extensive simulation studies. We also analyze the mortality dataset to illustrate the usefulness of the proposed procedure.

20.
J Oral Rehabil ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987903

RESUMO

BACKGROUND: Poor oral conditions in the elderly may have numerous effects on general health, including physical fitness and performance. OBJECTIVES: This study aimed to determine the relationship between oral health and physical function in elderly people. METHODS: Physical function and oral health parameters were compared using parametric comparison tests and Pearson correlation analyses. In addition, principal components analysis, hierarchical clustering and multidimensional scaling analysis clustered the patients' physical and oral health scores. The relationship between the groups was also determined using decision tree analysis. RESULTS: A total of 112 elderly patients participated in the study. Grip strength (GS) was higher in patients with high chewing ability, and Timed Up and Go (TUG) scores were lower in the high oral health group (p < .05). GS was correlated with Decay, Missing, and Filled Teeth Index (DMFT) and the number of remaining and functional teeth (p < .05). According to principal component analysis, it was seen that there were three components (oral, functional and quality of life (QoL) parameters), and the features that were related to each other were gathered together. TUG and GS showed the highest relative importance among physical function criteria in the classification based on chewing ability. They were GS and physical activity for oral health-related QoL. CONCLUSION: In the elderly, higher physical function parameters, especially GS may be an indicator of a better oral health and oral health-related QoL. Preventive physical rehabilitation practices, in addition to oral treatments, may be effective in improving oral health in the elderly.

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