Search

The prototyping protocol to evaluate and make the potential adjustments prior to finalization of the monolithic restorations was described by two clinical situations. In the first case report, following the digital impressions using an intraoral scanner (3Shape Trios, 3Shape) for an implant-supported four-unit fixed dental prosthesis, a digital design (3Shape Dental System, 3Shape) was performed and a prototype using subtractive CAM (milling) (PMMA, Telio CAD, Ivoclar Vivadent) was fabricated. The second case highlights the 3D-printed prototyping (additive CAM) (Sheraprint Model Plus UV, Shera) following digital impressions using an intraoral scanner and digital design in a patient requiring two opposing open-end three-unit fixed dental prostheses. By means of prototyping, the esthetic, fitting, and functional properties could be tested and the adjustments were completed on the prototypes. It is suggested that prototyping is an efficient tool that minimizes the clinical adjustment need for the final restoration while improving the communication between the dental practitioner and the technician. [ABSTRACT FROM AUTHOR]

This paper proposes a rolling horizon (RH) approach to deal with management problems under dynamic demand in planning horizons with variable lead times using system dynamics (SD) simulation. Thus, the nature of dynamic RH solutions entails no inconveniences to contemplate planning horizons with unpredictable demands. This is mainly because information is periodically updated and replanning is done in time. Therefore, inventory and logistic costs may be lower. For the first time, an RH is applied for demand management with variable lead times along with SD simulation models, which allowed the use of lot-sizing techniques to be evaluated (Wagner-Whitin and Silver-Meal). The basic scenario is based on a real-world example from an automotive single-level SC composed of a first-tier supplier and a car assembler that contemplates uncertain demands while planning the RH and 216 subscenarios by modifying constant and variable lead times, holding costs and order costs, combined with lot-sizing techniques. Twenty-eight more replications comprising 504 new subscenarios with variable lead times are generated to represent a relative variation coefficient of the initial demand. We conclude that our RH simulation approach, along with lot-sizing techniques, can generate more sustainable planning results in total costs, fill rates and bullwhip effect terms. [ABSTRACT FROM AUTHOR]

Calcium (Ca) plays a vital role as a macronutrient in the growth and development of plants. In order of decreasing solubility, Ca can be found in vegetal tissues as soluble Ca (Fraction I), bound Ca (mainly pectates, Fraction II), inorganic insoluble Ca (mainly phosphates and carbonates, Fraction III) and organic insoluble Ca or oxalate (Fraction IV). To explore the impact of Ca fertilizer application on plant growth and its allocation among different fractions, young citrus trees were fed over a complete vegetative cycle with a 44Ca labeled fertilizer (T1-Ca), while control plants (T2) received no Ca fertilizer. The results showed that plants receiving Ca exhibited significantly greater biomass. 44Ca derived from the fertilizer was localized mainly in sink organs (new flush leaves–twigs and fibrous roots). The primary fraction responsible for total Ca partitioning was Fraction II, followed by Fraction III or IV. Citrus plants, commonly found in calcareous soils, demonstrated improved growth with calcium treatments, indicating a positive link between calcium supplementation and enhanced development. The calcium supplied through the fertilizer (44Ca) was predominantly concentrated in sink organs (mainly in Ca-pectate fraction), including new flush leaves and twigs above ground, as well as fibrous roots below ground. [ABSTRACT FROM AUTHOR]

Glutathione S‐transferase theta 1 (GSTT1) is an enzyme involved in phase II biotransformation processes and a member of a multigene family of detoxifying and clearing reactive oxygen species. GSTT1 is polymorphic like other biotransforming enzymes, allowing variability in hepatic conjugation processes. Immunological recognition of the GSTT1 alloantigen, as evidenced by donor‐specific antibodies formation, has previously been observed in recipients lacking GSTT1 protein (called GSTT1−, GSTT*0, null phenotype or homozygous for the GSTT1 deletion) who receive liver or kidney transplants from GSTT1+ donors and is a risk factor for the development of de novo hepatitis following liver transplants from a GSTT1 expressing donor. Antibodies against GSTT1 are demonstrated in patients who are GSTT1 null and received a transplant from a GSTT1+ donor. Understanding the local population frequency of the GSTT1 deletion is of value in understanding the potential clinical risk of developing post‐transplant complications, which can be attributed to the nonexpression of GSTT1. A population of 173 healthy donors of the Murcia Region in Southeast Spain was evaluated for a null allele of GSTT1 (n = 173). DNA was extracted, and GSTT‐1 null allele detection was performed by real‐time polymerase chain reaction. The frequency of the null GSTT1 genotype (nonexpression or deletion of the homozygous polymorphism of the GSTT1 protein) was 17.9% (n = 31 null allele GSTT1/173 total individuals). Our data suggest that the frequency of null GSTT1 mutations in our population in Southeast Spain is 17.9%, lower than in other Caucasoid populations. This would convert our recipient population into more susceptible to nonlocal potential organ donors and less susceptible to local donors. All recipients bearing this GSTT1 deletion homozygous would be without the protein and triggering an alloantigen in the case of transplantation with a donor without deletion. [ABSTRACT FROM AUTHOR]

Me propongo una incursión a ciertas territorialidades en las ficciones de Borges. Deseo indagar además los cambios que se producen en las últimas etapas de su producción. Al mismo tiempo dejo abiertas las posibilidades para profundizar y extender la búsqueda y el análisis.

Aun con sus dificultades y limitaciones, el aprendizaje por indagación está considerado uno de los enfoques didácticos más idóneos para aprender ciencia haciendo ciencia. A fin de ponerlo en práctica en educación infantil, se diseñó una propuesta didáctica basada en secuencias de pregunta-predicción-comprobación. La propuesta se implementó con 83 niños de 2 a 4 años. El propósito era utilizar el aprendizaje por indagación para la iniciación a la ciencia en esta etapa educativa. El tópico elegido fue el de los cambios de estado del agua, del chocolate y de un polo flash. Se apreció una evolución de las ideas y capacidades de los niños para formular predicciones y comprobarlas experimentalmente. Se concluye que es posible aprender sobre la relación entre «calentar» o «enfriar» y las transformaciones entre el sólido y el líquido. Muchos llegan a caracterizar cada producto según su estado. Como implicaciones, se estiman pertinentes las actividades manipulativas acompañadas de preguntas y requerimiento de predicciones desde el inicio de educación infantil.

Interoception, the monitoring of visceral signals, is often presumed to engage attentional mechanisms specifically devoted to inner bodily sensing. In fact, most standardized interoceptive tasks require directing attention to internal signals. However, most studies in the field have failed to compare attentional modulations between internally- and externally-driven processes, thus probing blind to the specificity of the former. Here we address this issue through a multidimensional approach combining behavioral measures, analyses of event-related potentials and functional connectivity via high-density electroencephalography, and intracranial recordings. In Study 1, 50 healthy volunteers performed a heartbeat detection task as we recorded modulations of the heartbeat-evoked potential (HEP) in three conditions: exteroception, basal interoception (also termed interoceptive accuracy), and post-feedback interoception (sometimes called interoceptive learning). In Study 2, to evaluate whether key interoceptive areas (posterior insula, inferior frontal gyrus, amygdala, and somatosensory cortex) were differentially modulated by externally- and internally-driven processes, we analyzed human intracranial recordings with depth electrodes in these regions. This unique technique provides a very fine grained spatio-temporal resolution compared to other techniques, such as EEG or fMRI. We found that both interoceptive conditions in Study 1 yielded greater HEP amplitudes than the exteroceptive one. In addition, connectivity analysis showed that post-feedback interoception, relative to basal interoception, involved enhanced long-distance connections linking frontal and posterior regions. Moreover, results from Study 2 showed a differentiation between oscillations during basal interoception (broadband: 35–110 Hz) and exteroception (1–35 Hz) in the insula, the amygdala, the somatosensory cortex, and the inferior frontal gyrus. In sum, this work provides convergent evidence for the specificity and dynamics of attentional mechanisms involved in interoception.

Recent works evince the critical role of visual short-term memory (STM) binding deficits as a clinical and preclinical marker of Alzheimer’s disease (AD). These studies suggest a potential role of posterior brain regions in both the neurocognitive deficits of Alzheimer’s patients and STM binding in general. Thereupon, we surmised that stimulation of the posterior parietal cortex (PPC) might be a successful approach to tackle working memory deficits in this condition, especially at early stages. To date, no causal evidence exists of the role of the parietal cortex in STM binding. A unique approach to assess this issue is afforded by single-subject direct intracranial electrical stimulation of specific brain regions during a relevant cognitive task. Electrical stimulation has been used both for clinical purposes and to causally probe brain mechanisms. Previous evidence of electrical currents spreading through white matter along well defined functional circuits indicates that visual working memory mechanisms are subserved by a specific widely distributed network. Here, we stimulated the parietal cortex of a subject with intracranial electrodes as he performed the visual STM task. We compared the ensuing results to those from a non-stimulated condition and to the performance of a matched control group. In brief, direct stimulation of the parietal cortex induced a selective improvement in STM. These results, together with previous studies, provide very preliminary but promising ground to examine behavioral changes upon parietal stimulation in AD. We discuss our results regarding: (a) the usefulness of the task to target prodromal stages of AD; (b) the role of a posterior network in STM binding and in AD; and (c) the potential opportunity to improve STM binding through brain stimulation.

In the present manuscript the short term effect (3–24 h) of a saline shock (NaCl 100 mM) on fresh weight, water content, respiration rate, ethylene production and Na+, Cl-, ACC and polyamine concentration was studied in four plant species with different salt sensitivity, pepper, lettuce, spinach, and beetroot. Higher reduction in fresh weight and water content as a consequence of saline shock was found in pepper and lettuce plants than in spinach and beetroot, the latter behaving as more salinity tolerant. In general, salinity led to rapid increases in respiration rate, ethylene production and ACC and polyamine (putrescine, spermidine, and spermine) concentrations in shoot and root. These increases were related to plant salinity sensitivity, since they were higher in the most sensitive species and vice versa. However, ethylene and respiration rates in salt stressed plants recovered similar values to controls after 24 h of treatment in salt tolerant plants, while still remaining high in the most sensitive. On the other hand, sudden increases in putrescine, spermidine, and spermine concentration were higher and occurred earlier in pepper and lettuce, the most sensitive species, than in spinach and beetroot, the less sensitive ones. These increases tended to disappear after 24 h, except in lettuce. These changes would support the conclusion that ethylene and polyamine increases could be considered as a plant response to saline shock and related to the plant species sensitivity to this stress. In addition, no competition between polyamines and ethylene biosynthesis for their common precursor was observed.

Background: This study investigated verb argument structure effects in children with specific language impairment (SLI). Aims: A picture-naming paradigm was used to compare the response times and naming accuracy for nouns and verbs with differing argument structure between Spanish-speaking children with and without language impairment. Methods & Procedures: Twenty-four children with SLI (ages 5;3-8;2 [years;months]), 24 age-matched controls (ages 5;3-8;2), 24 MLU-w controls (ages 3;3-7;1 years), and 31 adults participated in a picture-naming study. Outcomes & Results: The results show all groups produced more correct responses and were faster for nouns than all verbs together. As regards verb type accuracy, there were no differences between groups in naming one-argument verbs. However, for both two- and three-argument verbs, children with SLI were less accurate than adults and age-matched controls, but similar to the MLU-matched controls. For verb type latency, children with SLI were slower than both the age-matched controls and adults for one- and two-argument verbs, while no differences were found in three-argument verbs. No differences were found between children with SLI and MLU-matched controls for any verb type. Conclusions & Implications: It has been shown that the naming of verbs is delayed in Spanish children with SLI. It is suggested that children with SLI may have problems encoding semantic representations. (Contains 7 tables, 3 figures, and 1 note.)

Es compara el currículum de ciències espanyol en educació primària (ensenyaments mínims nacionals) amb els d'Anglaterra i EE. UU., i es fan propostes de millora. A les finalitats proposem la inclusió de nocions de naturalesa de la ciència i èmfasi en la ciència recreativa. Per els continguts, suggerim una revisió general per un panell d'experts en cadascuna de les matèries de ciències i la seva didàctica, una major sistematització de cada contingut al llarg dels tres cicles i una millor articulació dels continguts amb la resta de diferents elements curriculars.

For the approximation of stiff systems of ODEs arising from chemistry kinetics, implicit integrators emerge as good candidates. This paper proposes a variational approach for this type of systems. In addition to introducing the technique, we present its most basic properties and test its numerical performance through some experiments. The main advantage with respect to other implicit methods is that our approach has a global convergence. The other approaches need to ensure convergence of the iterative scheme used to approximate the associated nonlinear equations that appear for the implicitness. Notice that these iterative methods, for these nonlinear equations, have bounded basins of attraction.

We have recently proposed a variational framework for the approximation of systems of differential equations. We associated, in a natural way, with the original problem, a certain error functional. The discretization is based on standard descent schemes, and we can use a variable-step implementation. The minimization problem has a unique solution, and the approach has a global convergence. The use of our error-functional strategy was considered by other authors, but using a completely different way to derive the discretization. Their technique was based on the use of an integral form of the Euler equation for a related optimal control problem, combined with an adapted version of the shooting method, and the cyclic coordinate descent method. In this note, we illustrate and compare our strategy to theirs from a numerical point of view.