Carbon dioxide concentration in Mediterranean greenhouses : how much lost production?

In the absence of artificial supply of carbon dioxide in the greenhouse environment, the CO2 absorbed in the process of photosynthesis must ultimately come from the external ambient through the ventilation openings. This requires that the CO2 concentration within the house must be lower than the external concentration, as there would be no flow inwards otherwise. Since potential assimilation (that is, the assimilation level that can be attained when no other factor is limiting) is heavily dependent on carbon dioxide concentration, this implies that assimilation is reduced, whatever the light level or crop status. The ventilation of the greenhouse implies a trade-off between ensuring inflow of carbon dioxide and maintaining an adequate temperature within the house, particularly during sunny, chilly days. We apply a simple model, on which the Dutch ¿philosophy¿ of CO2 fertilisation is based, for estimating the potential production loss, through data measured in commercial greenhouses in Almeria and Sicily. Thereafter we discuss the management options for a grower to limit losses. In particular we analyse costs, potential benefits and consequences of bringing in more carbon dioxide either through increased ventilation, at the cost of lowering temperature, or through artificial supply. We find out that, whereas the reduction in production caused by depletion is comparable to the reduction resulting from the lower temperature caused by ventilation to avoid depletion, compensating the effect of depletion is much cheaper than making up the loss by heating

Economic integration and FDI: an empirical analysis of foreign investment in the EU and in Central and Eastern Europe

Recent evidence suggests that regional economic integration provides an important stimulus not only to trade, but also to FDI. In contrast, the available theory on FDI does not yet provide empirically testable propositions on the effects of concurrent trade and investment liberalisation. Moreover, given the limits of simulation models, which rely heavily upon parameter choice, in assessing the impact of such liberalisation, there is a need for empirical analysis to identify the principal features of FDI. This paper uses a 'gravity model' approach to assess the impact of the deepening integration between the EU and the CEECs on FDI flows in terms of three key issues. First, we provide systematic estimates of the expected long-term level of FDI in the CEECs. Second, we investigate whether FDI in the CEECs, on the one hand, and source country exports and imports, on the other hand, are complements or substitutes. Finally, we enquire whether an increase in the attractiveness of the CEECs to foreign investors has affected the magnitude of FDI going to other European countries.foreign direct investment,transition economies,gravity model

Kinetics of fat and protein secretion in dairy cattle, sheep, goats and buffaloes

The negative correlations of fat and protein concentrations and milk yield, existing in all ruminants dairy species (Oftedal, 1984; Mepham, 1987), reflect a deep mechanism regulating the respective kinetics of secretion of carrier (mainly lactose which is the major responsible for the water drawn to the milk) and of fat and protein. Whereas the correlation coefficients are low (from –0.2 to – 0.4), fat and protein daily yield and milk production are positively and strongly linked (r = 0.8÷0.9). It means that more productive animals have higher fat and protein yield, but their milk has lower concentration of these components. The aim of this work is to investigate the relationships between milk, fat and protein yield in all main ruminant dairy species by using a simple mathematical model

Peripheral Blood and Milk Leukocytes Subsets of Lactating Sarda Ewes

Leukocytes subpopulations in blood and milk of lactating Sarda ewes were investigated. Animals characterized by a SSC level <500×103cells/mL and a negative bacteriological examination were sampled in early, mid and late lactation. Milk differential cell count evidenced that macrophage represented the main population (42.8%±3.5) followed by lymphocytes (40.2%±3.4) and neutrophils (8,6%±2.1). Flow cytometry analysis showed that lymphocytes subsets in milk were quite different from blood. High CD8+ and low CD4+ lymphocytes percentages determined a CD4/CD8 ratio inversion in milk compared to blood (0.3%±0.03 vs 1.8%±0.08). CD8+ decreased while, conversely, CD4+ increased in late lactation. γδ T cells were more represented in milk (12.6%±1.3) than in blood (6.8%±0.3) and their proportions appeared similar throughout lactation in both compartments. IL-2 receptor was mainly expressed in milk on T cytotoxic lymphocytes. Data obtained in uninfected mammary glands could allow an early discrimination between physiological and pathological changes occurring in ewe milk. Further phenotypical and functional studies on milk leukocytes subsets might help to understand defense mechanisms of the ovine mammary gland against IMI

Reluctant virginity: the relationship between sexual status and self-esteem

The purpose of this study is to identify group differences between sexual status (reluctant virgins, satisfied virgins, and non-virgins) in college students. Specifically, this study explored differences between groups in self-esteem (global, social, and body), dating (length of relationship and number of dating partners), and the beliefs in the double standard mediating differences in self-esteem. It was hypothesized that reluctant virgins would have lower self-esteem and shorter relationships than satisfied virgins and non-virgins. There was modest support for the stated hypotheses: reluctant virgins had lower social self esteem (M= 114.4) than non-virgins (M= 138.5). Reluctant virgins also had a poorer body image (M = 153.9) than both satisfied virgins (M = 196.57) and non-virgins (M= 155.12). Lastly, reluctant virgins experienced shorter dating relationships (M= 6.00) than non-virgins (M= 25.5)

Power transmission systems: from traditional to magnetic gearboxes

L'abstract è presente nell'allegato / the abstract is in the attachmen

Functional interactions between the hippocampus, medial entorhinal cortex and medial prefrontal cortex for spatial and nonspatial processing

Memory formation and recall depend on a complex circuit that includes the hippocampus and associated cortical regions. The goal of this thesis was to understand how two of the cortical connections, the medial entorhinal cortex (MEC) and medial prefrontal cortex (mPFC), influence spatial and nonspatial activity in the hippocampus. Cells in the MEC exhibit prominent spatially selective activity and have been hypothesized to drive place representation in the hippocampus. In Experiment 1 the MEC was transiently inactivated using the inhibitory opsin ArchaerhodopsinT (ArchT), and simultaneous recordings from CA1 were made as rats ran on an elliptical track. In response to MEC disruption some cells in the hippocampus shifted the preferred location of activity, some changed firing rate and others were unaffected. The new representation that developed following MEC disruption remained stable despite the fact that inhibition was transient. If the MEC is the source of spatial activity in the hippocampus the activity would be either time-locked to periods of inhibition or unstable throughout the period of inconsistent input. These results show that the MEC guides spatial representation in the hippocampus but does not directly drive spatial firing. The mPFC is generally thought to guide behavior in response to contextual elements. Experiment 2 examined the interaction between the mPFC and the hippocampus as rats performed a contextual discrimination task. Recordings were made in CA1, and the mPFC was disrupted using ArchT during the odor sampling phase of the discrimination. As animals perform this task neurons in the hippocampus respond to a conjunction of odor and location which indicates an association of what and where information in the hippocampus. Optogenetic disruption of the mPFC led to a decrease in nonspatial representation. Individual cells showed lower levels of odor selectivity, but there was no change in the level of spatial representation. This indicates that the mPFC is important for determining how the hippocampus represents nonspatial information but does not alter the spatial representation. The results are discussed within a model of memory formation that includes binding spatial and nonspatial information in the hippocampus

Comparison of parametric, orthogonal, and spline functions to model individual lactation curves for milk yield in Canadian Holsteins

Test day records for milk yield of 57,390 first lactation Canadian Holsteins were analyzed with a linear model that included the fixed effects of herd-test date and days in milk (DIM) interval nested within age and calving season. Residuals from this model were analyzed as a new variable and fitted with a five parameter model, fourth-order Legendre polynomials, with linear, quadratic and cubic spline models with three knots. The fit of the models was rather poor, with about 30%-40% of the curves showing an adjusted R-square lower than 0.20 across all models. Results underline a great difficulty in modelling individual deviations around the mean curve for milk yield. However, the Ali and Schaeffer (5 parameter) model and the fourth-order Legendre polynomials were able to detect two basic shapes of individual deviations among the mean curve. Quadratic and, especially, cubic spline functions had better fitting performances but a poor predictive ability due to their great flexibility that results in an abrupt change of the estimated curve when data are missing. Parametric and orthogonal polynomials seem to be robust and affordable under this standpoint

A Case Study Describing the Experiences of the Sexually Abused Children and Non-Offending Parents who Attended the Multi-Disciplinary Investigation Team After Care Clinic

Purpose. This study examines the experiences of children and their non-offending parents who attended the Multi-disciplinary Investigation Team‘s (MIT) After Care Clinic. The study seeks to understand the ways in which the care provided at the After Care Clinic helped stabilize the child and the non-offending parent. Additionally, this study explores what strategies were effective in stabilizing the families and resulted in their cooperation with prosecution of the perpetrator. Method. Seven children and their non-offending parents simultaneously attended 12 weeks of trauma treatment with two trauma therapists. The case studies used for this study were based on clinical notes and observations that were documented in the case notes. All data used were secondary. Each child in the study attended the MIT After Care Clinic and was forensically interviewed by the Danbury Multi-disciplinary Investigation Team after a sexual abuse disclosure. Following the forensic interview, the child and the non-offending parent were referred to the After Care Clinic for therapy. Results and Conclusion. The findings from the study identified strategies from the trauma therapy that were effective in stabilizing both the child and the non-offending parent. The findings also identified that having the clinicians be trained forensic interviewers assisted in ascertaining additional disclosures and court-worthy information. Overall, the families that engaged in treatment at the MIT After Care Clinic had outcomes that resulted in convictions. Recommendations for Further Study. Further study is needed. Many victims and their families are devastated by the disclosure of sexual abuse and are in need of support. There have been multiple studies conducted on trauma therapy, child abuse disclosure, and the necessity for support by the non-offending parent. The following is a list of recommendations that would continue to support this area of study: (a) compare the conviction rates of sexual offenders with conviction rates of sexual offenders when families are not engaged in therapy connected with a Multi-disciplinary Investigation Team, (b) perform a study with a larger number of families, (c) perform a study for children and families in group therapy and look at the success rates of trauma symptom reduction and court corporation, and (d) perform a study in which there is only one clinician, who is not forensically trained, connected to a Multi-disciplinary Investigation Team that is providing services to the victim

Symbols of America Standard-Bearer of a New World Order An Autobiographical Interpretation of U.S. Culture and Civilization in the Twentieth Century

Throughout my internship in Latin America I was faced with the dilemma of representing U.S. culture and civilization. This paper represents the synthesis of an introspective process of self-realization as a cultural being. The format is partially autobiographical and partially historical. The process involved the separating out of certain cultural tendencies derived from a largely materialistic background of training and replacing these with a more spiritual view of American identity which I perceived to be consistent with the original intentions of the Founders of the U.S.A. The process thus led to a more enlightened vision of U.S. culture and its role in the global community. This resulted in a common sense approach to teaching U.S. culture as it relates to other cultures. After the approach was synthesized it was discovered that Community Language Learning as outlined by Dr. Charles Curran to be consistent as an applied methodology to the assumptions of the approach