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OBJECTIVES: This paper aims to examine the psychometric properties of social capital indicators, comparing Black and White respondents to identify the extent of measurement invariance in social capital by race. STUDY DESIGN: We used data from the longitudinal study Midlife in the United States (MIDUS), waves 1 through 3 (1995-2016). METHODS: Data were from 6513 respondents (5604 White and 909 Black respondents). Social capital indicators were social cohesion, contributions to community, and community involvement. We used Structural Equation Modeling and Item Response Theory methods to test for measurement invariance in social capital by race. RESULTS: We observed violations of longitudinal and multi-group measurement invariance (MI) at configural and metric levels on two scales. Factor structures and indicator loadings were inconsistent over time. In IRT analysis, 'Many people come for advice' exhibited Differential Item Functioning (DIF), indicating a consistent advantage for White respondents on the contributions to community scale. Despite similar social capital levels (P(χ2,2) = 0.00), DIF was found in all contributions to community items and some community involvement items when examining race and education interaction. CONCLUSIONS: Invariance issues in social capital items suggest potential biases in comparing Black and White respondents. Recognizing these biases is essential. Future social capital research should assess existing data assumptions and involve stakeholders from diverse communities in creating new items.
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Negro o Afroamericano , Psicometría , Capital Social , Población Blanca , Humanos , Negro o Afroamericano/psicología , Negro o Afroamericano/estadística & datos numéricos , Población Blanca/estadística & datos numéricos , Población Blanca/psicología , Estudios Longitudinales , Persona de Mediana Edad , Femenino , Masculino , Estados Unidos , Equidad en Salud , Anciano , Disparidades en el Estado de Salud , AdultoRESUMEN
This study evaluated the effects of replacing cereal grains and soybean meal with by-products (BY) on production performance, nutrient digestibility, ruminal fermentation, nutrient recovery, and eating and chewing behavior of moderate-producing dairy cows under heat-stress conditions. Twelve multiparous Holstein cows (116.7 ± 12.01 d in milk; 42.7 ± 5.06 kg/d milk yield; 665 ± 77 kg body weight; mean ± SD) were used in a replicated 3 × 3 Latin square with 28-d periods (21 d for diet adaptation and 7 d for sampling and data collection). Cows were fed a total mixed ration containing a 39.2:60.8 ratio of forage to concentrate throughout the experiment. All diets were formulated to be isoenergetic and isonitrogenous, with different concentrates. Diets were (1) control diet based on cereal grains (CON: ground corn and ground barley, plus soybean meal); (2) sugar-rich BY diet (S-BY-CM: beet pulp, citrus pulp, and liquid molasses, plus canola meal); and (3) cereal grain BY diet (CG-BY: rice bran, corn germ meal, wheat bran, barley sprout, and broken corn). Our results showed that replacing grains with BY increased neutral detergent fiber intake and digestibility but decreased starch intake, human-edible energy, and human-edible protein. Milk yield and dry matter intake (DMI) decreased more in cows fed the CG-BY diet compared with the other 2 treatments. In contrast, no significant differences were observed between the CON and S-BY-CM diets in terms of milk yield and DMI. The S-BY-CM diet increased energy-corrected milk production compared with the CG-BY diet (36.2 vs. 34.3 kg/d), but CG-BY enhanced feed conversion efficiency compared with the other 2 treatments. Although the S-BY-CM diet prolonged the eating and sorting of small particles, neither of the dietary treatments affected chewing activity or ruminal pH 4 h after feeding. Furthermore, both diets containing BY contributed to an increase in milk fat content in comparison to the CON group. Additionally, the CG-BY and S-BY-CM diets demonstrated better performance than the CON diet in terms of human-edible feed conversion efficiency for protein and energy. The results indicated that S-BY-CM can completely replace barley and corn grain in the diet of mid-lactating dairy cows exposed to heat-stress conditions without any negative effect on production and ruminal pH. However, the inclusion of CG-BY did impair DMI, milk yield, and digestibility of nutrients and is not recommended during heat-stress conditions.
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Hordeum , Lactancia , Femenino , Humanos , Bovinos , Animales , Ensilaje/análisis , Hordeum/metabolismo , Grano Comestible , Calor , Dieta/veterinaria , Leche/química , Zea mays/metabolismo , Rumen/metabolismo , DigestiónRESUMEN
BACKGROUND AND PURPOSE: Signal analysis of FLAIR sequences is gaining momentum for studying neurodevelopment and brain maturation, but FLAIR intensity varies across scanners and needs to be normalized. This study aimed to establish normative values for standardized FLAIR intensity in the pediatric brain. MATERIALS AND METHODS: A new automated algorithm for signal normalization was used to standardize FLAIR intensity across scanners and subjects. Mean intensity was extracted from GM, WM, deep GM, and cortical GM regions. Regression curves were fitted across the pediatric age range, and ANOVA was used to investigate intensity differences across age groups. Correlations between intensity and regional volume were also examined. RESULTS: We analyzed 429 pediatric FLAIR sequences in children 2-19 years of age with a median age of 11.2 years, including 199 males and 230 females. WM intensity had a parabolic relationship with age, with significant differences between various age groups (P < .05). GM and cortical GM intensity increased over the pediatric age range, with significant differences between early childhood and adolescence (P < .05). There were no significant relationships between volume and intensity in early childhood, while there were significant positive and negative correlations (P < .05) in WM and GM, respectively, for increasing age groups. Only the oldest age group showed significant differences between males and females (P < .05). CONCLUSIONS: This work presents a FLAIR intensity standardization algorithm to normalize intensity across large data sets, which allows FLAIR intensity to be used to compare regions and individuals as a surrogate measure of the developing pediatric brain.
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Algoritmos , Encéfalo , Femenino , Masculino , Humanos , Adolescente , Niño , Preescolar , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética , Movimiento (Física) , ConvulsionesRESUMEN
The present study investigated the effects of adding wheat straw treated with exogenous fibrolytic enzymes (EFE) and a probiotic supplement to finely ground starters on growth performance, rumen fermentation, behavior, digestibility, and health of dairy calves. A total of 48 Holstein dairy calves (39.8 ± 1.67 kg body weight) were randomly assigned to one of 4 nutritional treatments (n = 12 calves per treatment). The experiment was conducted in a 2 × 2 factorial arrangement of treatments consisting of two diets with or without EFE-treated wheat straw (2 g/day/calf) and diets with or without probiotics (2 g/day/calf). All calves were weaned on day 63 and remained in the study until day 84. The addition of EFE to wheat straw had no effect on starter feed intake, increased neutral detergent fiber (NDF) digestibility and recumbency, but decreased average daily gain (ADG) after weaning (240 g/d). The addition of probiotics to the diet had no effect on starter feed intake, improved feed efficiency, ADG (150 g/d), final weight (11.3 kg), and NDF digestibility, and decreased the ratio of acetate to propionate in the rumen. The addition of probiotics to starter feed for calves could improve their growth.
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Alimentación Animal , Probióticos , Animales , Bovinos , Alimentación Animal/análisis , Peso Corporal , Dieta/veterinaria , Fibras de la Dieta/metabolismo , Fibras de la Dieta/farmacología , Fermentación , Probióticos/farmacología , Rumen/metabolismo , Triticum , DesteteRESUMEN
A novel biomarker panel was proposed to quantify macro and microstructural biomarkers from the normal-appearing brain matter (NABM) in multicentre fluid-attenuation inversion recovery (FLAIR) MRI. The NABM is composed of the white and gray matter regions of the brain, with the lesions and cerebrospinal fluid removed. The primary hypothesis was that NABM biomarkers from FLAIR MRI are related to cognitive outcome as determined by MoCA score. There were three groups of features designed for this task based on 1) texture: microstructural integrity (MII), macrostructural damage (MAD), microstructural damage (MID), 2) intensity: median, skewness, kurtosis and 3) volume: NABM to ICV volume ratio. Biomarkers were extracted from over 1400 imaging volumes from more than 87 centres and unadjusted ANOVA analysis revealed significant differences in means of the MII, MAD, and NABM volume biomarkers across all cognitive groups. In an adjusted ANCOVA model, a significant relationship between MoCA categories was found that was dependent on subject age for MII, MAD, intensity, kurtosis and NABM volume biomarkers. These results demonstrate that structural brain changes in the NABM are related to cognitive outcome (with different relationships depending on the age of the subjects). Therefore these biomarkers have high potential for clinical translation. As a secondary hypothesis, we investigated whether texture features from FLAIR MRI can quantify microstructural changes related to how "structured" or "damaged" the tissue is. Based on correlation analysis with diffusion weighted MRI (dMRI), it was shown that FLAIR MRI texture biomarkers (MII and MAD) had strong correlations to mean diffusivity (MD) which is related to tissue degeneration in the GM and WM regions. As FLAIR MRI is routinely collected for clinical neurological examinations, novel biomarkers from FLAIR MRI could be used to supplement current clinical biomarkers and for monitoring disease progression. Biomarkers could also be used to stratify patients into homogeneous disease subgroups for clinical trials, or to learn more about mechanistic development of dementia disease.
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Imagen por Resonancia Magnética , Sustancia Blanca , Biomarcadores , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Cognición , Sustancia Gris/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patologíaRESUMEN
AIM: To analyse and visualize the knowledge structure of scientific articles in the field of Endodontology with high altmetric attention scores to discover hot topics, active researchers and the journals involved. METHODOLOGY: On 5 June 2019, the altmetric database (Altmetric LLP, London, UK) was searched using the titles of 11 endodontic journals. Bibliometric data from endodontic articles and journals with an altmetric score >5 (top 5%) were retrieved from PubMed and analysed using the VOSviewer. Science mapping of articles with an altmetric score >5 at two levels was created: author keywords co-occurrence and co-authorship network analysis. RESULTS: Of the 2197 articles in the field of Endodontology identified with altmetrics, 192 had altmetric scores >5 (top 5%). Considering the total mentions amongst all altmetric resources, the Journal of Endodontics had the highest rank followed by the International Endodontic Journal and Australian Endodontic Journal. Twitter was the most popular altmetric data resource followed by patents and Facebook. Meta-analysis, systematic review and pulpitis were the hot topics. At the author level, Dummer P.M.H had the greatest influence on the network. There was no significant correlation between altmetric score and citations count (P > 0.05). Mendeley mentions correlated with citations (P < 0.05). CONCLUSIONS: Overall, the altmetric scores of topics within Endodontology were low, possibly due to the specific and specialized nature of the specialty, as well as the difficulty members of the public probably have in understanding endodontic research. Journals and researchers with a focus on Endodontology would have more influence if they were to set-up their own social media profiles and thus enhance their visibility and social impact by immediately sharing research findings and communicating with their network and audience.
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Endodoncia , Medios de Comunicación Sociales , Australia , Bibliometría , Factor de Impacto de la Revista , Metaanálisis como AsuntoRESUMEN
BACKGROUND AND PURPOSE: Accurate follow-up of metastatic brain tumors has important implications for patient prognosis and management. The aim of this study was to develop and evaluate the accuracy of a semiautomated algorithm in detecting growing or shrinking metastatic brain tumors on longitudinal brain MRIs. MATERIALS AND METHODS: We used 50 pairs of successive MR imaging datasets, 30 on 1.5T and 20 on 3T, containing contrast-enhanced 3D T1-weighted sequences. These yielded 150 growing or shrinking metastatic brain tumors. To detect them, we completed 2 major steps: 1) spatial normalization and calculation of the Jacobian operator field to quantify changes between scans, and 2) metastatic brain tumor candidate segmentation and detection of volume-changing metastatic brain tumors with the Jacobian operator field. Receiver operating characteristic analysis was used to assess the detection accuracy of the algorithm, and it was verified with jackknife resampling. The reference standard was based on detections by a neuroradiologist. RESULTS: The areas under the receiver operating characteristic curves were 0.925 for 1.5T and 0.965 for 3T. Furthermore, at its optimal performance, the algorithm achieved a sensitivity of 85.1% and 92.1% and specificity of 86.7% and 91.3% for 1.5T and 3T, respectively. Vessels were responsible for most false-positives. Newly developed or resolved metastatic brain tumors were a major source of false-negatives. CONCLUSIONS: The proposed algorithm could detect volume-changing metastatic brain tumors on longitudinal brain MRIs with statistically high accuracy, demonstrating its potential as a computer-aided change-detection tool for complementing the performance of radiologists, decreasing inter- and intraobserver variability, and improving efficacy.
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Algoritmos , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/secundario , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Anciano de 80 o más Años , Reacciones Falso Negativas , Reacciones Falso Positivas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Curva ROC , Estudios Retrospectivos , Sensibilidad y Especificidad , Adulto JovenRESUMEN
CONTEXT: Two of the problems of the placement of posts in teeth with short roots are to determine the minimum length of the canal obturation material at the apical third of the root canal and removal of all the canal obturation material from the root canal during post space preparation. AIM: The aim of the present study was to compare the coronal microleakage of mineral trioxide aggregate (MTA) plug and gutta-percha in short roots prepared for post placement using the bacterial penetration technique. MATERIALS AND METHODS: In the presentin vitro study, 40 extracted single-rooted anterior teeth measuring 13 mm in root length were selected. Since the roots were short, 3 mm of the root length was allocated to the root canal obturation material and 10 mm of the root length was allocated to post placement. After preparation of the root canals, post spaces were prepared and the samples were randomly divided into two groups of gutta-percha and MTA. Fifteen root canals were obturated with gutta-percha and the post space was immediately prepared, with 3 mm of gutta-percha remaining in the apical end of the root canal. In 15 teeth, MTA plugs were placed, which measured 3 mm in length. The samples were placed in the Enterococcus faecalis bacterial microleakage system for 120 days. The time for the turbidity of each sample was recorded. Data were analyzed with Fisher's exact test. RESULTS: During the study period, turbidity was observed in all the gutta-percha samples and in only four MTA samples, with statistically significant differences between the two groups (P< 0.001). CONCLUSION: Based on the results, MTA exhibited much better sealing ability compared to gutta-percha as a root canal obturation material in teeth with short roots.
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Compuestos de Aluminio/química , Compuestos de Calcio/química , Filtración Dental , Óxidos/química , Técnica de Perno Muñón , Materiales de Obturación del Conducto Radicular/química , Silicatos/química , Combinación de Medicamentos , Enterococcus faecalis , Gutapercha/química , Humanos , Técnicas In Vitro , Ensayo de Materiales , Obturación del Conducto RadicularRESUMEN
AIM: To evaluate the therapeutic effect of Simvastatin on apical periodontitis in rats by assessing the osteoblast production of receptor activator of nuclear factor-Kappa B Ligand (RANKL) and Osteoprotegerin (OPG) cytokines that are essential for bone resorption. METHODOLOGY: Twenty-five healthy 8- to 10-week-old male rats were selected. Periapical lesions were induced by exposure of pulps through the occlusal surfaces of mandibular first molars. The pulps were extirpated and canals contaminated with saliva. The teeth were filled temporarily to make animal feeding feasible. The experimental group (n = 12) was placed on 20 mg(-1) kg(-1) day(-1) of Simvastatin for 10 days (3 days before and 7 days after pulp exposure) and the control group (n = 12) received a placebo. After 1, 2 and 4 weeks, the animals were sacrificed and mRNA expression of OPG/RANKL was evaluated by real-time PCR. One rat was sacrificed without any interventions (negative control) to determine the baseline expression of the mediators involved. Data were analysed by one-way anova. RESULTS: Simvastatin significantly (P < 0.05) enhanced the expression of OPG and reduced the mRNA expression of RANKL in the experimental group compared with the control group. CONCLUSIONS: Oral administration of Simvastatin attenuated RANKL expression and accelerated OPG expression in induced rat periapical lesions.
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Osteoprotegerina/metabolismo , ARN Mensajero/metabolismo , Simvastatina/farmacología , Animales , Cinética , Ligandos , Masculino , Ratas , Ratas Wistar , Reacción en Cadena en Tiempo Real de la Polimerasa , Simvastatina/farmacocinéticaRESUMEN
BACKGROUND: Carpal tunnel syndrome (CTS) is entrapment of median nerve in carpal tunnel of the wrist. The prevalence of CTS related to pregnancy and non-pregnancy is unknown in some countries such as Iran. The main aim of this study was to determine the prevalence of CTS in women of Boyerahmad Township located in South-West part of Iran. METHODS: This cross-sectional descriptive analytic study was done since February 2010 to January 2011 in Obstetrics and Gynecology clinics in 2656 non-pregnant and 1508 pregnant women. The women that had clinical symptoms of CTS performed standard electro diagnostic techniques for rule in or rule out of CTS. RESULTS: The prevalence of CTS in pregnant and non- pregnant women was 3.4 and 2 .3 percent respectively. The prevalence of CTS in all women was 2.7%. Overall, 51 pregnant women had CTS that 59.4% had mild, 18.8 % had moderate and 21.9% had severe CTS. Sixty-one non-pregnant women had CTS that 73.6 %had mild, 20.8 %t had moderate and 5.6 % had severe CTS. CONCLUSION: Although the prevalence of CTS in Iranian pregnancy is higher than non-pregnancy women conservative treatment is safe and more effective.
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Listeria monotogenes bacteria-ascites developed in a 73-year-old man who had cholangiocarcinoma and liver metastasis. Spontaneous bacterial peritonitis (SBP) is a frequent complication in patients with chronic liver disease and ascites. L. peritonitis has been reported in only <30 cases world-wide. Our patient represents a unique case of L. peritonitis without peritoneal fluid analysis consistent with spontaneous bacteria peritonitis. However, the culture of the ascitic fluid provided the final diagnosis in this case.