Communicative Predictors of a Shared Family Identity: Comparison of Grandchildren’s Perceptions of Family-of-Origin Grandparents and Stepgrandparents

From an intergroup perspective on family relationships, the current study investigates family-of-origin grandparents and stepgrandparents to determine similarities and differences in communication and relational dimensions. Participants (N = 88) completed questionnaires on family-of-origin grandparents and stepgrandparent relationships. From the perspective of young adult grandchildren, the research explores the role of supportive communication, reciprocal self-disclosure, nonaccommodative communication, and parental encouragement in predicting a sense of shared family identity with each grandparent type. Results are discussed in terms of implications for intergroup research, grandparent-grandchild communication, and stepfamily relationships

Respiratory plasticity in response to changes in oxygen supply and demand

Aerobic organisms maintain O2 homeostasis by responding to changes in O2 supply and demand in both short and long time domains. In this review, we introduce several specific examples of respiratory plasticity induced by chronic changes in O2 supply (environmental hypoxia or hyperoxia) and demand (exercise-induced and temperature-induced changes in aerobic metabolism). These studies reveal that plasticity occurs throughout the respiratory system, including modifications to the gas exchanger, respiratory pigments, respiratory muscles, and the neural control systems responsible for ventilating the gas exchanger. While some of these responses appear appropriate (e.g., increases in lung surface area, blood O2 capacity, and pulmonary ventilation in hypoxia), other responses are potentially harmful (e.g., increased muscle fatigability). Thus, it may be difficult to predict whole-animal performance based on the plasticity of a single system. Moreover, plastic responses may differ quantitatively and qualitatively at different developmental stages. Much of the current research in this field is focused on identifying the cellular and molecular mechanisms underlying respiratory plasticity. These studies suggest that a few key molecules, such as hypoxia inducible factor (HIF) and erythropoietin, may be involved in the expression of diverse forms of plasticity within and across species. Studying the various ways in which animals respond to respiratory challenges will enable a better understanding of the integrative response to chronic changes in O2 supply and deman

Mitochondrial physiology

As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

Bilingualism and regional entrepreneurship

Entrepreneurship makes important contributions to both regional and national economies, however, entrepreneurship rates vary significantly across and within regions. We apply the communication accommodation theory lens to examine the role that bilingualism plays in regional entrepreneurship. We use aggregated firm and district level longitudinal data on eight north-eastern districts in the region of South Tyrol (Italy) during 2000-2015 and demonstrate positive direct effect of bilingualism on entrepreneurship activity and non-linear effect on business dynamics. Results can be generalizable to other European regions

Ventilatory responses to acute and chronic hypoxia are altered in female but not male Paskin-deficient mice

Proteins harboring a Per-Arnt-Sim (PAS) domain are versatile and allow archaea, bacteria and plants to sense oxygen partial pressure as well as light intensity and redox potential. A PAS domain associated with a histidine kinase domain is found in FixL, the oxygen sensor molecule of Rhizobium species. Considering the PAS fold PASKIN is the mammalian homolog of FixL, but its function is far from being understood. Using whole body plethysmography we evaluated the ventilatory response to acute and chronic hypoxia of homozygous deficient male and female PASKIN mice (Paskin-/-). While only slight ventilatory differences were found in males, female Paskin-/- mice increased ventilatory response to acute hypoxia. Unexpectedly, females had an impaired ability to reach ventilatory acclimatization in response to chronic hypoxia. Central control of ventilation occurs in the brainstem respiratory centers and is modulated by catecholamines via tyrosine hydroxylase (TH) activity. We observed that TH activity was altered in male and female Paskin-/- mice. Peripheral chemoreceptor effects on ventilation were evaluated by exposing animals to hyperoxia (Dejours test) and domperidone, a peripheral ventilatory stimulant drug directly affecting the carotid sinus nerve discharge. Male and female Paskin-/- had normal peripheral chemosensory (carotid bodies) responses. In summary, our observations suggest that PASKIN is involved in the central control of hypoxic ventilation, modulating ventilation in a gender-dependent manner

Hypoxia tolerance in animals: biology and application

Abstract Many invertebrates and ectothermic vertebrates successfully cope with a fluctuating supply of ambient oxygen-and consequently, a highly variable tissue oxygenation-through increasing their antioxidant barriers. During chronic deprivation of oxygen, however, the hypometabolic defense mode of the fruit fly Drosophila, the hypoxia-induced behavioral hypothermia of the crayfish Pacifastacus leniusculus, and the production of ethanol during anoxia by the crucian carp Carassius carassius all indicate that these animals are also capable of utilizing a suite of genetic and physiological defenses to survive otherwise lethal reductions in tissue oxygenation. Normally, much of an organism's gene response to hypoxia is orchestrated via the hypoxia-inducible transcription factor HIF. Recent developments expand our view of HIF function even further by highlighting regulatory roles for HIF in the hypometabolism of insects, in the molting and the normoxic immune response of crustaceans, and in the control-via the downstream effector gene erythropoietin-of the hypoxic ventilatory response and pulmonary hypertension in mammals. These and related topics were collectively presented by the authors in a symposium of the 2008 ICA-CBP conference at Mara National Reserve, Kenya, Africa. This synthesis article communicates the essence of the symposium presentations to the wider community