Localization of free and bound aromatic compounds among skin, juice and pulp fractions some grape varieties

The localization and distribution of free and glycosidically-bound aroma compounds among the skin, pulp and juice of three red grape varieties (Vitis vinifera L. var. Monastrell, Cabernet Sauvignon and Tempranillo) have been studied. An Amberlite XAD-2 column was utilized to separate and extract the free aroma compounds and the glycosidically-bound aromatic compounds. A commercial enzymatic preparation (Pectinol C) was used to release the bound aroma compounds. Gas chromatography and gas chromatography-mass spectrometry were used for the analysis of the compounds. The results showed that the major compounds in these varieties were alcohols and aldehydes, the skin being the fraction with the largest quantities of aromatic compounds. After the enzymatic hydrolysis. the analysis of the liberated compounds showed that they were mainly alcohols and monoterpenes. Two monoterpenes that did not appear as free aroma compounds could he found

L1CAM binds ErbB receptors through Ig-like domains coupling cell adhesion and neuregulin signalling.

During nervous system development different cell-to-cell communication mechanisms operate in parallel guiding migrating neurons and growing axons to generate complex arrays of neural circuits. How such a system works in coordination is not well understood. Cross-regulatory interactions between different signalling pathways and redundancy between them can increase precision and fidelity of guidance systems. Immunoglobulin superfamily proteins of the NCAM and L1 families couple specific substrate recognition and cell adhesion with the activation of receptor tyrosine kinases. Thus it has been shown that L1CAM-mediated cell adhesion promotes the activation of the EGFR (erbB1) from Drosophila to humans. Here we explore the specificity of the molecular interaction between L1CAM and the erbB receptor family. We show that L1CAM binds physically erbB receptors in both heterologous systems and the mammalian developing brain. Different Ig-like domains located in the extracellular part of L1CAM can support this interaction. Interestingly, binding of L1CAM to erbB enhances its response to neuregulins. During development this may synergize with the activation of erbB receptors through L1CAM homophilic interactions, conferring diffusible neuregulins specificity for cells or axons that interact with the substrate through L1CAM

Urgencias neurológicas y guardias de Neurología

In recent years different studies have highlighted a progressive increase in the demand for neurological care in emergency departments. To analyze the convenience of specific neurology shifts or the role that the neurologist should play in the emergency department, it is necessary to answer questions such as: What is the demand for emergency neurological care? What are the most frequent neurological emergencies? Who should attend to neurological emergencies and why? Are specific neurology shifts necessary? Neurological emergencies account for between 2.6% and 14% of medical emergencies. Stroke represents a third of all neurological emergencies, while the diagnoses of acute cerebrovascular disease, epilepsy and cephalea constitute 50% of all neurological care in the emergency department. On the basis of quality of care criteria and professional competence, the best care for patients with a neurological emergency is provided by a specialist in neurology. The implementation of specific neurology shifts, with a 24 hour physical presence, is associated with greater quality of care, better diagnostic and therapeutic orientation from the moment the patient arrives in emergency department, reduces unnecessary admissions, reduces costs and strengthens the neurology service

Perceptions of Self-Efficacy & Support Among Secondary Early-Career Teachers and their Principals During the COVID-19 Pandemic

In response to challenges faced by middle and high school educators during the COVID-19 pandemic, a study was conducted in the Spring of 2021 involving 33 early-career mathematics teachers and eight supervising school principals in the State of California. These participants completed detailed surveys which provided demographic information, as well as perceptions of support, efficacy and job satisfaction. Findings show a variety of associations among teacher perceptions of support and their efficacy and job satisfaction in the face of challenging circumstances. As it related to principal support and recognition, principal participants expressed confidence in their ability to support teachers as a result of the pandemic, including understanding best practices for evaluating teachers for online teaching. Additionally, while agreeing that teachers at their schools needed more professional development in instructional practice, participating school principals felt they supported their teachers as they adapted instruction due to the COVID-19 pandemic. This study aspires to inform practitioners and policymakers alike in their understanding of teachers and their principals as they responded to significant challenges as a result of the COVID-19 pandemic

Fuzzy synchronization of chaotic systems with hidden attractors

Chaotic systems are hard to synchronize, and no general solution exists. The presence of hidden attractors makes finding a solution particularly elusive. Successful synchronization critically depends on the control strategy, which must be carefully chosen considering system features such as the presence of hidden attractors. We studied the feasibility of fuzzy control for synchronizing chaotic systems with hidden attractors and employed a special numerical integration method that takes advantage of the oscillatory characteristic of chaotic systems. We hypothesized that fuzzy synchronization and the chosen numerical integration method can successfully deal with this case of synchronization. We tested two synchronization schemes: complete synchronization, which leverages linearization, and projective synchronization, capitalizing on parallel distributed compensation (PDC). We applied the proposal to a set of known chaotic systems of integer order with hidden attractors. Our results indicated that fuzzy control strategies combined with the special numerical integration method are effective tools to synchronize chaotic systems with hidden attractors. In addition, for projective synchronization, we propose a new strategy to optimize error convergence. Furthermore, we tested and compared different Takagi-Sugeno (T-S) fuzzy models obtained by tensor product (TP) model transformation. We found an effect of the fuzzy model of the chaotic system on the synchronization performance