Jordan weak amenability and orthogonal forms on JB*-algebras

We prove the existence of a linear isometric correspondence between the Banach space of all symmetric orthogonal forms on a JB$^*$-algebra $\mathcal{J}$ and the Banach space of all purely Jordan generalized derivations from $\mathcal{J}$ into $\mathcal{J}^*$. We also establish the existence of a similar linear isometric correspondence between the Banach spaces of all anti-symmetric orthogonal forms on $\mathcal{J}$, and of all Lie Jordan derivations from $\mathcal{J}$ into $\mathcal{J}^*$

Heat flow in the postquasistatic approximation

We apply the postquasistatic approximation to study the evolution of spherically symmetric fluid distributions undergoing dissipation in the form of radial heat flow. For a model which corresponds to an incompressible fluid departing from the static equilibrium, it is not possible to go far from the initial state after the emission of a small amount of energy. Initially collapsing distributions of matter are not permitted. Emission of energy can be considered as a mechanism to avoid the collapse. If the distribution collapses initially and emits one hundredth of the initial mass only the outermost layers evolve. For a model which corresponds to a highly compressed Fermi gas, only the outermost shell can evolve with a shorter hydrodynamic time scale.Comment: 5 pages, 5 figure

Estructura del nectario floral, presentación del néctar y análisis morfo-anatómico de anteras de líneas androfértiles y androestériles en cebolla (Allium cepa, Amaryllidaceae)

Background and aims: The onion (Allium cepa var. cepa) is an allogamous species in which male-sterile lines have been developed. However, the structure of the flower and floral nectaries have only been briefly described. The objective of this study is to update the floral anatomy data, comparing the gynoecium and androecium of male-fertile and male-sterile lines, and to analyze the three-dimensional structure of the floral nectary. M&M: Conventional optical and scanning electron microscopy techniques were used. Results: Fertile and sterile male flowers have the same structural organization. The septal or gynopleural nectary is organized in three zones: 1) production area formed by the glandular tissue arranged radially in the septa of the ovary, 2) discharge zone: a small channel at the apex connects the nectariferous tissue with the pocket formed between the ovary wall and the overlying ridge, and 3) presentation and harvest zone, where the excreted nectar accumulates, formed between the widened base of the inner staminal filaments opposite the ovary. Conclusions: The only anatomical differences in the flowers sterile male lines are the lack of pollen production and the absence of dehiscence, despite having a normal stomium and anther wall. The floral nectaries of onion are a clear example of secondary presentation of nectar.Introducción y objetivos: La cebolla (Allium cepa var. cepa) es una especie alógama, donde se han desarrollado líneas androestériles. La estructura floral y la de sus nectarios florales ha sido descrita de manera somera e incompleta. El objetivo del presente trabajo es actualizar los datos de la anatomía floral comparando líneas fértiles y androestériles y analizar la estructura tridimensional del nectario floral.  M&M: Se utilizaron técnicas convencionales de microscopía óptica y electrónica de barrido.  Resultados: Las flores fértiles y androestériles presentan la misma organización estructural. El nectario septal o ginopleural se organiza en tres zonas: 1) área productora formada por el tejido glandular dispuesto radialmente en los septos del ovario, 2) zona de descarga: un pequeño canal en el ápice conecta el tejido nectarífero con el bolsillo formado entre la pared del ovario y la cresta que los cubre, y 3) zona de presentación y cosecha, donde el néctar excretado se acumula, formada entre la base ensanchada de los filamentos estaminales internos y la base del ovario.  Conclusiones: Las únicas diferencias anatómicas en las flores de las líneas androestériles y las fértiles radican en la falta de producción de granos de polen y la ausencia de dehiscencia, pese a presentar estomio y pared de anteras normales. Los nectarios florales de la cebolla son un claro ejemplo de presentación secundaria del néctar

Family Dynamics and Personal Strengths among Dementia Caregivers in Argentina

This study examined whether healthier family dynamics were associated with higher personal strengths of resilience, sense of coherence, and optimism among dementia caregivers in Argentina. Caregivers are usually required to assist individuals with dementia, and family members have typically fulfilled that role. Personal strengths such as resilience, sense of coherence, and optimism have been shown to protect caregivers from some of the negative experiences of providing care, though the family-related variables associated with these personal strengths are largely unknown. Hierarchical multiple regressions investigated the extent to which family dynamics variables are associated with each of the caregiver personal strengths after controlling for demographic and caregiver characteristics. A sample of 105 caregivers from Argentina completed a set of questionnaires during a neurologist visit. Family dynamics explained 32% of the variance in resilience and 39% of the variance in sense of coherence. Greater family empathy and decreased family problems were uniquely associated with higher resilience. Greater communication and decreased family problems were uniquely associated with higher sense of coherence. Optimism was not found to be significantly associated with family dynamics. These results suggest that caregiver intervention research focused on the family may help improve caregiver personal strengths in Argentina and other Latin American countries