Comparing algorithms for diffeomorphic registration: Stationary LDDMM and Diffeomorphic Demons

International audienceThe stationary parameterization of diffeomorphisms is be- ing increasingly used in computational anatomy. In certain applications it provides similar results to the non-stationary parameterization alle- viating the computational charge. With this characterization for diffeo- morphisms, two different registration algorithms have been recently pro- posed: stationary LDDMM and diffeomorphic Demons. To our knowl- edge, their theoretical and practical differences have not been analyzed yet. In this article we provide a comparison between both algorithms in a common framework. To this end, we have studied the differences in the elements of both registration scenarios. We have analyzed the sen- sitivity of the regularization parameters in the smoothness of the final transformations and compared the performance of the registration re- sults. Moreover, we have studied the potential of both algorithms for the computation of essential operations for further statistical analysis. We have found that both methods have comparable performance in terms of image matching although the transformations are qualitatively different in some cases. Diffeomorphic Demons shows a slight advantage in terms of computational time. However, it does not provide as stationary LD- DMM the vector field in the tangent space needed to compute statistics or exact inverse transformations

Functional Feed Assessment on Litopenaeus vannamei Using 100% Fish Meal Replacement by Soybean Meal, High Levels of Complex Carbohydrates and Bacillus Probiotic Strains

Functional feed supplemented with alternative-economic nutrient sources (protein, carbohydrates, lipids) and probiotics are being considered in shrimp/fish aquaculture production systems as an option to increase yield and profits and to reduce water pollution. In this study the probiotic potential to formulate functional feeds have been evaluated using four dietary treatments: Treatment 1 (B + Bs); Bacillus subtilis potential probiotic strain was supplemented to a soybeanmeal (SBM)—carbohydrates (CHO) basal feed. Treatment 2 (B + Bm); Bacillus megaterium potential probiotic strain was supplemented to the same SBM-CHO basal feed. In Treatment 3 (B); SBM-CHO basal feed was not supplemented with probiotic strains. Treatment 4 (C); fishmeal commercial feed (FM) was utilized as positive control. Feeding trials evaluated the survival, growth, and food conversion ratio and stress tolerance of juvenile Litopenaeus vannamei (Boone) Pacific white shrimp. Best overall shrimp performance was observed for animals fed with Treatment 1 (B+Bs); additionally, stress tolerance and hemolymph metabolites also showed the best performance in this treatment. SBM-CHO basal feed not supplemented with probiotic strains (B) presented smaller growth and lower feed conversion ratio (FCR). Shrimps fed with the fishmeal commercial feed (C) presented the lowest stress tolerance to high ammonia and low oxygen levels. Specifically selected B. subtilis strains are recommended to formulate functional and economical feeds containing high levels of vegetable; protein and carbohydrates as main dietary sources in L. vannamei cultures

A different role for hydrogen peroxide and the antioxidative system under short and long salt stress in Brassica oleracea roots

Salinity affects normal growth and development of plants depending on their capacity to overcome the induced stress. The present study was focused on the response and regulation of the antioxidant defence system in Brassica oleracea roots under short and long salt treatments. The function and the implications of hydrogen peroxide as a stressor or as a signalling molecule were also studied. Two different zones were analysed—the elongation and differentiation zone and the fully differentiated root zone—in order to broaden the knowledge of the different effects of salt stress in root. In general, an accumulation of hydrogen peroxide was observed in both zones at the highest (80 mM NaCl) concentration. A higher accumulation of hydrogen peroxide was observed in the stele of salt-treated roots. At the subcellular level, mitochondria accumulated hydrogen peroxide in salt-treated roots. The results confirm a drastic decrease in the antioxidant enzymes catalase, ascorbate peroxidase, and peroxidases under short salt treatments. However, catalase and peroxidase activities were recovered under long salt stress treatments. The two antioxidant molecules analysed, ascorbate and glutathione, showed a different trend during salt treatments. Ascorbate was progressively accumulated and its redox state maintained, but glutathione was highly accumulated at 24 h of salt treatment, but then its concentration and redox state progressively decreased. Concomitantly, the antioxidant enzymes involved in ascorbate and glutathione regeneration were modified under salt stress treatments. In conclusion, the increase in ascorbate levels and the maintenance of the redox state seem to be critical for root growth and development under salt stress

Comorbidity patterns in patients with chronic diseases in general practice

INTRODUCTION: Healthcare management is oriented toward single diseases, yet multimorbidity is nevertheless the rule and there is a tendency for certain diseases to occur in clusters. This study sought to identify comorbidity patterns in patients with chronic diseases, by reference to number of comorbidities, age and sex, in a population receiving medical care from 129 general practitioners in Spain, in 2007. METHODS: A cross-sectional study was conducted in a health-area setting of the Madrid Autonomous Region (Comunidad Autónoma), covering a population of 198,670 individuals aged over 14 years. Multiple correspondences were analyzed to identify the clustering patterns of the conditions targeted. RESULTS: Forty-two percent (95% confidence interval [CI]: 41.8-42.2) of the registered population had at least one chronic condition. In all, 24.5% (95% CI: 24.3-24.6) of the population presented with multimorbidity. In the correspondence analysis, 98.3% of the total information was accounted for by three dimensions. The following four, age- and sex-related comorbidity patterns were identified: pattern B, showing a high comorbidity rate; pattern C, showing a low comorbidity rate; and two patterns, A and D, showing intermediate comorbidity rates. CONCLUSIONS: Four comorbidity patterns could be identified which grouped diseases as follows: one showing diseases with a high comorbidity burden; one showing diseases with a low comorbidity burden; and two showing diseases with an intermediate comorbidity burden.This study was partially supported by the CENIT Program (MICINN-CDTI) [CEN-2007-1010 ‘‘Digital personal environment for health and wellbeing – AmiVital’’ project], a grant from the Ministry of Health & Consumer Affairs [FIS PI08-0435], and the MOBIS Program of the Spanish Vodafone Foundation . The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.S

Transformación de las Mipymes restauranteras de Toluca ante la nueva normalidad; un análisis desde el comportamiento del consumidor

The Covid-19 pandemic left an uncertain scenario for the restaurant industry, thousands of companies closed by not resisting the lockdown period or not adapting to the new normality. Undoubtedly, it was the micro, small and medium-sized enterprises that presented the greatest difficulties since, unlike large companies, they did not have a contingency plan or sufficient financial and human resources, therefore, this research was carried out in the Historic Center of Toluca, State of Mexico, and aimed to analyze how this transformation occurred from evolutionary and revolutionary punctuated changes theory, where there is a momentum, in this case the health crisis and from the knowledge around the consumer. This was a non-experimental quantitative study and descriptive where it is concluded that the MSMEs studied were able to survive and break with inertia due to aspects that are traditionally considered business weaknesses; the absence of formal organizational structure which led to agile decision-making processes where empirical knowledge of the consumer behavior and the adoption of mainly technological innovations were the most relevant factors for survival.La pandemia por Covid-19 dejó un escenario incierto para la industria restaurantera, donde miles de empresas cerraron al no resistir el periodo del confinamiento o no adaptarse a la nueva normalidad. Sin duda, fueron las micro, pequeñas y medianas empresas las que presentaron mayores dificultades ya que a diferencia de grandes empresas éstas no contaban con un plan de contingencia ni con los recursos financieros y humanos suficientes, por lo cual, esta investigación se llevó a cabo en el Centro Histórico de Toluca, Estado de México, y tuvo como objetivo analizar cómo se dio la transformación a partir de la teoría de cambios puntuados evolucionarios y revolucionarios, donde existe un momentum, en este caso, la crisis sanitaria y desde el conocimiento entorno al consumidor. Este fue un estudio cuantitativo no experimental y descriptivo donde se logra concluir que las Mipymes estudiadas pudieron sobrevivir y romper con la inercia debido a aspectos que tradicionalmente se consideran debilidades empresariales; la ausencia de estructura organizacionales formales lo que propició procesos ágiles de toma de decisiones donde el conocimiento empírico del comportamiento del consumidor y la adopción de innovaciones principalmente tecnológicas, fueron los factores más relevantes para la supervivencia

Development of Kraft Lignin Chemically Modified as a Novel Crosslinking Agent for the Synthesis of Active Hydrogels

In this research a chemical modification of kraft lignin was carried out using a basic nucleophilic substitution reaction (NSA) in order to functionalize it as a novel crosslinking agent for the synthesis of active hydrogels. The chemical modification success of the synthesized crosslinker was demonstrated by using several techniques such as volumetry probes, FTIR, 1H-NMR and DSC. Thus, the obtained materials were employed during the synthesis of acrylic acid-based hydrogels, due to its high-water absorption capacity to evaluate their retention potential of heavy metal ions. Characterization of the active hydrogels were performed by FTIR and SEM, showing the specific signals corresponding to the base monomers into the polymer skeleton and the efficiency of modified kraft lignin as a novel crosslinking agent. Additionally, to demonstrate the potential use of these hydrogels in wastewater treatment, metal ions adsorption experiments were conducted, showing adsorption percentages higher than 90% and 80% for Pb2+ and Cu2+, respectively