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PREMISE: Bracken (Pteridium, Dennstaedtiaceae) is a cosmopolitan genus of aggressive disturbance colonizers that are toxic to agricultural livestock. The taxonomy of Pteridium has been treated in multiple schemes, ranging from one to six species worldwide, with numerous subspecies and varieties. Recent work has focused on the worldwide distribution and systematics of the bracken fern, but South America has been poorly represented. We present the first continent-wide sampling and analysis of Pteridium esculentum, a Southern Hemisphere diploid species. METHODS: Within South America, P. esculentum has several morphotypes, distinguished into subspecies by variation in indument and lamina architecture. We used double digest restriction site-associated DNA sequencing (ddRADSeq) to assess the phylogenetic relationships of P. esculentum subspecies. RESULTS: We found a striking genetic homogeneity in the species, being able to support only two morphotypes from molecular data: P. e. arachnoideum and P. e. campestre. We had high confidence for shallow and deep phylogenetic relationships, but less support for relationships among crown groups. CONCLUSIONS: We describe an east-west geographic pattern that would explain the relationships between populations; and, in contrast to previous studies, we detected differences with P. esculentum from Australia. These results will lay the foundations for studying variations in this species' behavior as a weed, as well as its impact on the production of agricultural livestock in South America.

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A continuous time multivariate stochastic model is proposed for assessing the damage of a multi-type epidemic cause to a population as it unfolds. The instants when cases occur and the magnitude of their injure are random. Thus, we define a cumulative damage based on counting processes and a multivariate mark process. For a large population we approximate the behavior of this damage process by its asymptotic distribution. Also, we analyze the distribution of the stopping times when the numbers of cases caused by the epidemic attain levels beyond certain thresholds. We focus on introducing some tools for statistical inference on the parameters related with the epidemic. In this regard, we present a general hypothesis test for homogeneity in epidemics and apply it to data of Covid-19 in Chile.

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The objective of this study was to select and characterize agronomically the advanced bread wheat line H - 1246 which gave origin to the INIA wheat variety 440 - K'ANCHAREQ. The research included yield trials in farmers' fields during 4 production seasons (2012-2016), adaptation and agronomic efficiency trials in two production seasons (2016-2018). In addition, the reaction to Yellow Rust and distinctness, uniformity and stability characteristics of the new wheat variety and commercial controls were evaluated. The plots for each of the trials were conducted under a Completely Randomized Block design with three replications. At the end of the trials, desirable characteristics in the baking industry such as hectoliter weight, protein, ash, gluten and flour moisture were evaluated. The results showed that the new INIA 440 - K'ANCHAREQ variety has ten clear differences in qualitative characteristics, which distinguish it from other varieties and remained constant during the trials. The yield trials between locations showed the adaptation of the INIA 440 - K'ANCHAREQ variety to the different locations due to its high yield and hectoliter weight values. At the locality level, Andenes obtained the highest values in most of the production seasons. Adaptation trials during the second season showed the superiority of the new INIA 440 - K'ANCHAREQ variety for variables such as yield, plant height, ear size and thousand grain weight. The new variety showed no signs of stripe rust during the trials. Industrial quality trials indicated that it has good characteristics for the baking industry.

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Social homogeneity, understood as the similarity of perceptions and attitudes that individuals display toward the environment around them, is explained by the relational context in which they are immersed. However, there is no consensus about which relational mechanism best explains social homogeneity. The purpose of this research is to find out which of the three classical relational processes most studied in network analysis (structural cohesion, role equivalence, or homophily) is more determinant in explaining social homogeneity. To achieve the research objective, 110 professionals (psychologists, social workers, and community facilitators) implementing a psychosocial care program in three regions of Northwest Colombia were interviewed. Different types of relationships among professionals were analyzed using network analysis techniques. To examine the structural cohesion hypothesis, interveners were categorized according to the level of structural cohesion by performing core-periphery analysis in the networks evaluated; to test the role equivalence hypothesis, participants were categorized according to their level of degree centrality in the networks examined; to test the homophily hypothesis, participants were grouped according to the level of homophily in terms of professional profile. The non-parametric tests showed that role equivalence was the most powerful mechanism for explaining social homogeneity in the sample of psychosocial interveners evaluated.

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In this paper, we examine whether social class and class divides in social networks contribute to individuals' attachment to society. We argue that network segregation restricts individuals' social worlds, thereby diminishing societal attachment. Our research site is Chile, a country with relatively low social cohesion and one of the world's highest levels of economic inequality. We use large-scale representative survey data collected in 2016 for the Chilean urban population aged 18-75 years (n = 2983) and interrelate indicators of well-established dimensions and sub-dimensions of societal attachment. Results of our regression analyses show that members of the upper middle class are more attached to society than their fellow citizens from other social strata. In addition, having more social contacts within one's own social class reduces attachment to society. In particular, network homogeneity lessens societal attachment for lower- and upper-class individuals, but not so strongly in the middle class. We conclude that social cohesion in Chilean society would be enhanced not only by more equal opportunities but also by changes to the social settings in which social class segregation is (re)produced.

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Objetivo: Evaluar radiográficamente tratamientos en- dodónticos del sector posterior de la cavidad bucal y com- parar la frecuencia de aceptabilidad en cada pieza dentaria involucrada. Materiales y métodos: Se evaluaron 5000 radiogra- fías de archivo de tratamientos endodónticos realizados apro- ximadamente entre 2005 y 2019 en premolares y molares mandibulares y maxilares en Argentina. Se consideraron tratamientos correctos e incorrectos de acuerdo con: 1) con- formación de la preparación quirúrgica; 2) límite apical de la obturación; 3) homogeneidad de la obturación. Se obtuvo la fre- cuencia absoluta y relativa de correctos e incorrectos. El aná- lisis entre frecuencias y pieza dentaria se realizó con la prueba de chi cuadrado y el cálculo del coeficiente V de Cramer. Para la comparación entre grupos de piezas dentarias se utilizó la partición del valor de chi cuadrado obtenido en los corres- pondientes grados de libertad. Nivel de significación P <0.05. Resultados: La partición del valor de chi cuadrado no mostró diferencias significativas entre primeros y segundos premolares mandibulares. Las otras comparaciones exhibie- ron diferencias significativas. Conclusiones: Un alto porcentaje de los tratamientos endodónticos de la población estudiada tiene por lo menos una condición que permite categorizarlos como incorrectos según el criterio establecido en este trabajo. Este porcentaje es más preponderante en anatomías complejas (AU)

Aim: To evaluate radiographically endodontic treat- ments performed in the posterior area of the oral cavity and compare the frequency of acceptability in each tooth involved. Materials and methods: 5,000 archival radiographs of endodontic treatments performed between 2005 and 2019 on mandibular and maxillary premolars and molars in Argentina were evaluated. The percentages of correct and incorrect treatments were considered according to 1) shaping of the preparation; 2) apical limit of the obturation; 3) homogeneity of the obturation. The absolute and relative frequencies of correct and incorrect treatments were calcu- lated. The association between these frequencies and tooth type was analyzed using the chi-square test and Cramer's V coefficient. For the comparison between groups of teeth, the partition of the chi-square value obtained in the corre- sponding degrees of freedom was used. Level of significance was P <0.05. Results: The partition of the chi-square value did not show a significant difference between the first and second lower premolars. The differences were significant in the other comparisons. Conclusions: A high percentage of the endodontic treat- ments in the study population have at least one condition war- ranting their classification as incorrect according to the crite- ria established in this study. This percentage is more prevalent in complex anatomies (AU)

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Coastal aquatic ecosystems such as estuaries and coastal lagoons are important atmospheric methane sources that must be better constrained. This work presents a detailed characterization of the methane cycle in a tropical coastal lagoon (La Mancha, Veracruz, Mexico) and its tributary river over three distinct seasons, along a transect from the river to the sea connection. In addition to several physicochemical parameters, the dissolved methane, carbon dioxide, and oxygen concentrations were measured with high resolution in the sediments and the water column, combined with production/uptake rates. Methane and carbon dioxide cycles were further constrained by determining atmospheric flux over the entire river and lagoon sections. The results indicate that La Mancha is a highly contrasted ecosystem. The river section is characterized by a strong pycnocline, relatively high methane concentration, and active methanogenesis and methanotrophy, discharging into a relatively homogeneous lagoon section where the methane and carbon cycles are less active. Overall, both the river and the lagoon were a net source of methane and carbon dioxide, with an annual emission of 2.9 metric tons of methane and 2757 metric tons of carbon dioxide. The spatial structure of the main components of the methane, carbon dioxide, and oxygen cycles was established, and it was observed that depthwise heterogeneities predominated in the river section. In contrast, lengthwise heterogeneities dominated in the lagoon section.

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This study proposes a preliminary assessment of the homogeneity and stability through digital image acquisition of a candidate for mechanically processed pumpkin seed meal reference material, exploring the concepts of homogeneity curve and the analysis of texture characteristics by Continuous-Level Moving Block through Robust Principal Component Analysis. This innovative methodology allowed us to examine the percentage of homogeneity in a set of samples, revealing an average of 41% with only one outlier in relation to the entire sample, indicating low homogeneity. In the stability study carried out after storing samples for 12 months at different temperatures, 83% of the samples were considered regular and 17% were outlier, which means that most of them were considered stable. Therefore, this methodology is useful for screening samples for homogeneity, by textural analysis, and detected non-homogeneity can be corrected in advance for quantification by standard protocols.

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The aim of this study was to evaluate the reasons of quality deviation of a concentrate from a predefined standard. Five treatments were established: T1 - Control, standard concentrate formulation (SCF); T2 - PXMore5, SCF with more 5% vitamin-mineral premix (VMP); T3 - PXLess5, SCF with less 5% VMP. All three treatments used a 400kg batches in an INTECNIAL mixer; T4 - FeedMixer, SCF using a 4,000kg batch in an IMOTO mixer; T5 - PremixMixer, SCF using a 1,200kg batch in an MUYANG mixer. For each treatment, bags of 20 kg were stored in three storage places for four months. Water activity of concentrate was affected by temperature and air relative humidity in different storage places. Regarding the kind of mixer, the greatest variation in concentration of crude protein, mineral residue, copper, zinc, and selenium was observed in the PremixMixer. Adjustments are imperative in the handling and use procedures of this kind of mixer to meet the quality requirements required in the concentrate production. Analyzing the effect of the mineral-vitamin premix level, no difference could be defined with the evaluated parameters.(AU)

O objetivo deste estudo foi avaliar as razões do desvio de qualidade de um concentrado de um padrão predefinido. Foram estabelecidos cinco tratamentos: T1 - controle, concentrado com formulação padrão (CFP); T2 - PXMais5, CFP com 5% a mais de vitaminas e minerais da pré-mistura (PVM); T3 - PXMenos5, CFP com 5% a menos de PVM. Todos esses três tratamentos utilizaram lotes de 400kg em um misturador INTECNIAL; T4 - FeedMixer, CFP usando um lote de 4.000kg em um misturador IMOTO; T5 - PremixMixer, CFP usando um lote de 1.200kg em um misturador MUYANG. Para cada tratamento, sacos de 20kg foram armazenados em três ambientes distintos por quatro meses. A atividade de água do concentrado foi afetada pela temperatura e umidade relativa do ar em diferentes locais de armazenamento. Em relação ao tipo de misturador, a maior variação na concentração de proteína bruta, resíduo mineral, cobre, zinco e selênio foi devido ao PremixMixer. Ajustes são imperativos nos procedimentos de manuseio e uso desse tipo de misturador para atender aos requisitos de qualidade exigidos na produção de concentrado. Ao se analisar o efeito do nível da pré-mistura de vitaminas e minerais, nenhuma diferença pôde ser definida com os parâmetros avaliados.(AU)

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A previously developed surface probe method, which allows for instantaneous methane (CH4) flux measurement, was used to establish CH4 emission maps of a municipal landfill with a final clay cover and equipped with a gas recollection system. In addition to spatial variations, the method was applied at 7 different times over a total timeframe of 65 h and under similar weather conditions to determine the intrinsic temporal variations of CH4 emissions; i.e., the temporal variation related to the dynamic of the landfill rather than the one driven by external factors. Furthermore, continuous CH4 fluxes, with a data acquisition frequency of 1 Hz, were measured during 12 h at a single position, and for one hour at 22 locations of the landfill, spanning a large range of CH4 emission magnitudes. A simple model for the numerical characterization of spatiotemporal variability of the landfill emission was used and allowed us to separately quantify the temporal and spatial variability. This model showed that, in the landfill tested, the temporal distribution of CH4 emissions resulted more homogeneous than the spatial distribution. Other attributes of the temporal and spatial distributions of CH4 emissions were also established including the anisotropic nature of the spatial distribution and, contrastingly, the stochastic temporal variability of such emissions.

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AIM: Our goal was to compare conformal 3D (C3D) radiotherapy (RT), modulated intensity RT (IMRT), and volumetric modulated arc therapy (VMAT) planning techniques in treating pituitary adenomas. BACKGROUND: RT is important for managing pituitary adenomas. Treatment planning advances allow for higher radiation dosing with less risk of affecting organs at risk (OAR). MATERIALS AND METHODS: We conducted a 5-year retrospective review of patients with pituitary adenoma treated with external beam radiation therapy (C3D with flattening filter, flattening filter-free [FFF], IMRT, and VMAT). We compared dose-volume histogram data. For OARs, we recorded D2%, maximum, and mean doses. For planning target volume (PTV), we registered V95%, V107%, D95%, D98%, D50%, D2%, minimum dose, conformity index (CI), and homogeneity index (HI). RESULTS: Fifty-eight patients with pituitary adenoma were included. Target-volume coverage was acceptable for all techniques. The HI values were 0.06, IMRT; 0.07, VMAT; 0.08, C3D; and 0.09, C3D FFF (p < 0.0001). VMAT and IMRT provided the best target volume conformity (CI, 0.64 and 0.74, respectively; p < 0.0001). VMAT yielded the lowest doses to the optic pathway, lens, and cochlea. The position of the neck in extreme flexion showed that it helps in planning mainly with VMAT by allowing only one arc to be used and achieving the desired conformity, decreasing the treatment time, while allowing greater protection to the organs of risk using C3D, C3DFFF. CONCLUSIONS: Our results confirmed that EBRT in pituitary adenomas using IMRT, VMAT, C3D, C3FFF provide adequate coverage to the target. VMAT with a single arc or incomplete arc had a better compliance with desired dosimetric goals, such as target coverage and normal structures dose constraints, as well as shorter treatment time. Neck extreme flexion may have benefits in treatment planning for better preservation of organs at risk. C3D with extreme neck flexion is an appropriate treatment option when other treatment techniques are not available.

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Objetivo: Evaluar radiográficamente, en dientes extraídos, el grado de homogeneidad y adaptación de las obturaciones endodónticas realizadas por alumnos de grado, comparando las técnicas de condensación lateral e híbrida. Materiales y métodos: Entre 2003 y 2017, los alumnos de tercer año de la Escuela de Odontología de la Universidad del Salvador / Asociación Odontológica Argentina realizaron 5.384 tratamientos endodónticos ex vivo empleando, para la obturación, las técnicas de condensación lateral e híbrida. En las radiografías posoperatorias, un docente especialista en endodoncia evaluó la homogeneidad y la adaptación de cada obturación para categorizarla como correcta o incorrecta. Para la comparación entre técnicas, dentro de cada año lectivo, se utilizó la prueba exacta de Fisher, y para el análisis porcentual de las observaciones, la prueba de Chi cuadrado. El nivel de significancia fue establecido en P<0,05. Resultados: Del total de 5.384 tratamientos, 4.970 (92,3%) mostraron obturaciones correctas. Con la técnica de condensación lateral, de los 1.741 tratamientos, 1.560 (89,6%) mostraron obturaciones correctas con la técnica híbrida, de los 3.643 tratamientos, 3.410 (93,6%) tuvieron obturaciones correctas. En función del tamaño total de las muestras, sumando todos los años, puede estimarse con 95% de confianza que la diferencia de obturaciones incorrectas entre ambas técnicas está entre el 2,3% y el 5,7%. Con la prueba del Chi cuadrado, se observa una diferencia significativa de obturaciones correctas a favor de la técnica híbrida (P<0,01) Conclusiones: La evaluación radiográfica de los tratamientos endodónticos realizados ex vivo por alumnos de pregrado mostró un alto porcentaje de obturaciones correctas. Así mismo, el empleo de la técnica híbrida dio, en general, mejores resultados de compactación de la masa del material obturador que la técnica de condensación lateral (AU)

Aim: To evaluate radiographically the degree of homogeneity and adaptation of endodontic obturations completed by undergraduate students in extracted teeth using lateral and hybrid condensation techniques. Materials and methods: Between 2003 and 2017, third year students of a the School of Dentistry of the Universidad del Salvador / Asociación Odontológica Argentina performed 5384 ex vivo endodontic treatments using lateral condensation and hybrid technique. In the postoperative radiographs, a specialist in endodontics assessed the homogeneity and adaptation of each obturation and categorize it as correct or incorrect. The data were submitted to statistical analysis to compare results obtained with the two techniques. Fisher and Chi-square tests were used and significance level was set at P<0.05. Results: Out of 5384 treatments, 4970 (92.3%) showed correct obturation. Within the 1741 treatments completed with the lateral condensation technique, 1560 (89.6%) were correct while within the 3634 where a hybrid technique was used, 3410 (93.6%) were correct. When the whole sample was considered (sum of treatment carried out during each of the academic years) a statistically significant difference (P<0.01) favoring the hybrid technique was found. The difference in incorrect cases can be estimated to be between 2.3% and 5.7% with 95% confidence. Conclusions: The radiographic evaluation completed by undergraduate students in extracted teeth showed a high percentage of correct fillings. The use of the hybrid technique showed, in general, better compaction of the obturation material than the lateral condensation technique (AU)

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Resting-state functional magnetic resonance imaging has been playing an important role in the study of amyotrophic lateral sclerosis (ALS). Although functional connectivity is widely studied, the patterns of spontaneous neural activity of the resting brain are important mechanisms that have been used recently to study a variety of conditions but remain less explored in ALS. Here we have used fractional amplitude of low-frequency fluctuation (fALFF) and regional homogeneity (ReHo) to study the regional dynamics of the resting brain of nondemented ALS patients compared with healthy controls. As expected, we found the sensorimotor network with changes in fALFF and ReHo, and also found the default mode network (DMN), frontoparietal network (FPN), and salience network (SN) altered and the cerebellum, although no structural changes between ALS patients and controls were reported in the regions with fALFF and ReHo changes. We show an altered pattern in the spontaneous low-frequency oscillations that is not confined to the motor areas and reveal a more widespread involvement of nonmotor regions, including those responsible for cognition.

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Sudden cardiac death (SCD) is one of the main causes of death among people. A new methodology is presented for predicting the SCD based on ECG signals employing the wavelet packet transform (WPT), a signal processing technique, homogeneity index (HI), a nonlinear measurement for time series signals, and the Enhanced Probabilistic Neural Network classification algorithm. The effectiveness and usefulness of the proposed method is evaluated using a database of measured ECG data acquired from 20 SCD and 18 normal patients. The proposed methodology presents the following significant advantages: (1) compared with previous works, the proposed methodology achieves a higher accuracy using a single nonlinear feature, HI, thus requiring low computational resource for predicting an SCD onset in real-time, unlike other methodologies proposed in the literature where a large number of nonlinear features are used to predict an SCD event; (2) it is capable of predicting the risk of developing an SCD event up to 20 min prior to the onset with a high accuracy of 95.8%, superseding the prior 12 min prediction time reported recently, and (3) it uses the ECG signal directly without the need for transforming the signal to a heart rate variability signal, thus saving time in the processing.

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The effects of excipients on the accuracy of tablet subdivision are severely underinvestigated. In this study, placebo tablets were prepared using a combined mixture design of fillers and binders to evaluate the effect of these excipients on subdivision accuracy. The responses assessed were mass loss, mass variation, tablet fragmentation, and increased friability. Dicalcium phosphate dihydrate (DCP) gave rise to more uniform and denser tablets than microcrystalline cellulose (MCC), thus resulting in greater subdivision accuracy. The binder type, hydroxypropylcellulose (HPC) or polyvinylpyrrolidone (PVP), did not affect the subdivision of DCP tablets. On the contrary, the structural similarity between HPC and MCC led to improved subdivision accuracy for MCC tablets. A less accurate subdivision was observed in tablets prepared with a DCP-MCC combination; this finding could be attributed to irregular binder distribution in this matrix. An optimized response was built using desirability analysis. This study helps to illuminate the relationship between fillers and binders to guide formulation scientists in the development of tablets with better subdivision performance.

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En el marco de las políticas públicas en Colombia sobre calidad de la educación superior se encuentran los lineamientos para que el Estado reconozca los programas de pregrado como de alta calidad, entre tales lineamientos se consideran los sistemas de evaluación de los estudiantes basados en políticas institucionales claras y transparentes que propicien una identificación integral de las condiciones académicas y actitudinales de los estudiantes por lo que es imprescindible tecnificar y modernizar los procesos de evaluación para fortalecer la emisión de inferencias confiables sobre el logro académico. En este artículo se describe una aplicación de la Teoría de Grafos usando algunas de sus definiciones y teoremas básicos con la intención de potenciar su uso para el estudio del supuesto de unidimensionalidad de la Teoría de Respuesta al Ítem como alternativa para robustecer la evaluación. La unidimensional fue entendida en el sentido de la homogeneidad escalar y de criterio para las relaciones de orden definidas por la dominación tanto para ítems como para evaluados: para los ítems conforme al número de evaluados que los contestaron correctamente y a la dificultad; para los evaluados respecto al número de respuestas correctas y a la habilidad. Se aplicó la combinación de las dos teorías a un caso de estudio que contempla el instrumento de la prueba diagnóstica del Examen de Clasificación de Matemáticas Básicas en la Universidad Jorge Tadeo Lozano, con esto se ofrece un valor agregado porque se evidencian los resultados de forma algorítmica y visual con ayuda de herramientas informáticas especializadas.

In Colombia, public policies about quality of higher education involve student assessment systems as a relevant characteristic. These systems should have clear and transparent institutional policies requiring comprehensive identification of attitudinal and academic conditions about examinee performance. Consequently, on the way of continuous improvement of academic services offered by institutions of higher education, an assessment process adequately technified allowing valid inferences about academic achievement is required. In this sense, the Rasch measurement model of Item Response Theory is a modern alternative to strengthen educational measurement estimating the ability of the student and the difficulty of the item on a comparable scale. Unidimensionality, local independence and internal consistency are assumptions made in Rasch measurement model. Unidimensionality assumption has several definitions, one of them is the occurrence of a dominant factor influencing test performance. Another definition is considered in the present study. Here, unidimensionality was interpreted as scalar and criterial homogeneity for the order relations defined by domination for items and assessed applicants. Graph Theory is an ideal mathematical modelling approach to this assumption inasmuch as represent intangible interactions as required. In order to achieve this, Graph Theory and Item Response Theory were combined to examine the qualifying test for the Basic Mathematics subject at Jorge Tadeo Lozano University as a case study. This test was composed by 45 items divided in three blocks. With several combinations of these blocks, three virtual booklets were obtained each one comprising 30 of them. From the application of June 2011, a test sample of 509 responses chains was obtained. Three data bases were processed one for each booklet, the first spanned 175 responses chains, the second 170 and the third one 164. To begin with the exmination on the Rasch measurement model, the parameters reliability, separation, Cronbach Alpha and item residual correlation were estimated to gauge and determine performance test for getting acceptable values in each booklet applied. Tatsuoka was followed to undertake the path to unidimensionality from Graph Theory gathering a real case experience processed with suitable software. Additionally, the sensitivity of the order relation was verified through: 1) ordering by number of correct responses per item (1I order) and items difficulty (2I order); 2) ordering by number of correct responses per applicant (1E order) and estimated ability (2E order). Furthermore, the linear models were obtained collating these orders. In like manner, three Guttman scales and their adjacency matrices were schematized one for each booklet. Subsequently, the respective graphs were processed and represented using Gephi just as a specialized tool that enables running some algorithms like Force Atlas. Afterwards, the second power of each adjacency matrix was found using Matlab 2014b and domination matrices were calculated for both items and applicants in the aforementioned orders for a total of 12 matrices. Consistency index developed by Cliff was computed for the domination matrices. As a result, moderate consistency was observed. Significant domination for the entries of these matrices was analyzed through McNemar test in order to have an asymmetric dominance relation. Moreover, a reachable matrix was calculated for each one of these significant domination matrices as a limit ofa sequence of boolean powers. Finally, dominance hierarchies were illustrated with vertex degrees and compared with student maps by the means of Winsteps 3.73. The combination of Graph Theory and Item Response Theory allowed a deeper comprehension of unidimensionality assumption. Thereupon, universities can optimize their resources offering to applicant differential academic options per individual position in the ability scale. The results can be used to outline advantages for the applicants who can evidence their position in the ability scale and identify the different areas to improve.

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The physical and chemical characteristics of gelatin have been used to justify its inclusion in extenders to preserve the sperm quality and improve results of cervical artificial insemination with cooled semen. The objective of this study was to evaluate the effects of gelatin supplementation in cooling extender on the quality and fertility of ram semen stored at 5°C. Semen samples (n = 24) of Santa Inês rams (n = 6) were diluted in Glycine-Yolk-Milk extender without (control) or with 1.5% of gelatin. The samples were loaded into 0.25 mL straws, cooled to 5°C and stored vertically for 48 and 72 hours. Sample quality was evaluated using straw homogeneity tests based on pH, osmolality and the proportion of spermatozoa (PS) in both upper and lower segments of straws (US and LS), analyses of sperm motility, plasma and acrosomal membrane integrity, and by fertility after artificial insemination. Differences between the US and LS of straws were found for pH and PS (%). They were significant only in the control group at both times: pH 5.96 vs. 5.71 at 48 h and 6.13 vs. 5.89 at 72 h; PS 21.66 vs. 78.34 at 48 h and 20.87 vs. 79.13 at 72 h. Storage in gelatin had very little, to no effect on the sperm kinetics or on the sperm membrane integrity evaluations. The addition of gelatin to the extender did not affect the pregnancy rate which ranged from 4.4 to 26.1%. We conclude that gelatin is effective in maintaining the physical and chemical homogeneity of the semen samples. Further research is needed in order to optimize the use of gelatin supplementation and elucidate any potential benefits.(AU)

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The physical and chemical characteristics of gelatin have been used to justify its inclusion in extenders to preserve the sperm quality and improve results of cervical artificial insemination with cooled semen. The objective of this study was to evaluate the effects of gelatin supplementation in cooling extender on the quality and fertility of ram semen stored at 5°C. Semen samples (n = 24) of Santa Inês rams (n = 6) were diluted in Glycine-Yolk-Milk extender without (control) or with 1.5% of gelatin. The samples were loaded into 0.25 mL straws, cooled to 5°C and stored vertically for 48 and 72 hours. Sample quality was evaluated using straw homogeneity tests based on pH, osmolality and the proportion of spermatozoa (PS) in both upper and lower segments of straws (US and LS), analyses of sperm motility, plasma and acrosomal membrane integrity, and by fertility after artificial insemination. Differences between the US and LS of straws were found for pH and PS (%). They were significant only in the control group at both times: pH – 5.96 vs. 5.71 at 48 h and 6.13 vs. 5.89 at 72 h; PS – 21.66 vs. 78.34 at 48 h and 20.87 vs. 79.13 at 72 h. Storage in gelatin had very little, to no effect on the sperm kinetics or on the sperm membrane integrity evaluations. The addition of gelatin to the extender did not affect the pregnancy rate which ranged from 4.4 to 26.1%. We conclude that gelatin is effective in maintaining the physical and chemical homogeneity of the semen samples. Further research is needed in order to optimize the use of gelatin supplementation and elucidate any potential benefits.

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The physical and chemical characteristics of gelatin have been used to justify its inclusion in extenders to preserve the sperm quality and improve results of cervical artificial insemination with cooled semen. The objective of this study was to evaluate the effects of gelatin supplementation in cooling extender on the quality and fertility of ram semen stored at 5°C. Semen samples (n = 24) of Santa Inês rams (n = 6) were diluted in Glycine-Yolk-Milk extender without (control) or with 1.5% of gelatin. The samples were loaded into 0.25 mL straws, cooled to 5°C and stored vertically for 48 and 72 hours. Sample quality was evaluated using straw homogeneity tests based on pH, osmolality and the proportion of spermatozoa (PS) in both upper and lower segments of straws (US and LS), analyses of sperm motility, plasma and acrosomal membrane integrity, and by fertility after artificial insemination. Differences between the US and LS of straws were found for pH and PS (%). They were significant only in the control group at both times: pH - 5.96 vs. 5.71 at 48 h and 6.13 vs. 5.89 at 72 h; PS - 21.66 vs. 78.34 at 48 h and 20.87 vs. 79.13 at 72 h. Storage in gelatin had very little, to no effect on the sperm kinetics or on the sperm membrane integrity evaluations. The addition of gelatin to the extender did not affect the pregnancy rate which ranged from 4.4 to 26.1%. We conclude that gelatin is effective in maintaining the physical and chemical homogeneity of the semen samples. Further research is needed in order to optimize the use of gelatin supplementation and elucidate any potential benefits.

RESUMO

Resumen La mayoría de la literatura sobre la psicopatía gira en torno a su medida. Cuatro son los instrumentos y familias de referencia en la evaluación de la psicopatía: la Psychopathy Checklist (PCL), la Levenson's Primary and Secondary Psychopathy Scales (LPSP), la Self-Report Psychopathy Scale (SRP), y el Psychopathic Personality Inventory (PPI). Ante este estado de la cuestión, nos planteamos llevar a cabo un metaanálisis psicométrico correlacional con el cual someter a prueba la validez convergente de estos instrumentos a nivel unidimensional y en los dos factores comunes a todos ellos: el factor afectivo y el factor antisocial. Los resultados mostraron una validez convergente positiva, significativa y generalizable entre los instrumentos, tanto en la dimensión psicopatía como en los factores afectivo y antisocial. Asimismo, los resultados pusieron de manifiesto que la PCL es el instrumento más idóneo para la evaluación de la psicopatía en poblaciones clínicas y el PPI en población subclínica.

Abstract Most of the literature on psychopathy is focused on its measurement. There are four reference tools used to assess psychopathy: the Psychopathy Checklist (PCL), the Levenson's Primary and Secondary Psychopathy Scales (LPSP), the Self-Report Psychopathy Scale (SRP), and the Psychopathic Personality Inventory (PPI). In order to do this, a psychometric correlational meta-analysis was designed to test the convergent validity between these tools on the psychopathy dimension and the two common factors among them: the affective and antisocial deviation factors. The results showed a positive, significant and generalisable convergent validity between tools, in the psychopathy dimension, as well as in the affective and antisocial factors. Moreover, the results also showed that the PCL was the most appropriate tool to measure psychopathy in clinical samples, and the PPI was so in sub-clinical cases.

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