Experimental display of generalized wave-particle duality

The quantification of wave-particle duality (WPD) by means of measurable features associated to it, such as fringe visibility ($\mathcal {V}$) and path distinguishability ($\mathcal {D}$), led to the establishment of the constraint $\mathcal {V}^{2}+\mathcal {D}^{2} \leq \,1$. The two involved quantities refer to so-called "quantons", physical objects that are capable of generating an interferometric pattern, while being at least partially localizable. Any quanton's internal degree of freedom (DOF) can in principle be used as a path-marker. When the quanton and its internal DOF are simultaneously engaged, new constraints can be derived and experimentally tested. Generalized constraints show how $\mathcal {V}$ and $\mathcal {D}$ relate to other quantifiers and bring to light coherences that might remain otherwise hidden in both quantum and classical light. We submitted two-qubit constraints to experimental tests, using optical light beams. This shows that, despite the rather contrived nature of the constraints, linear optics setups are appropriate to test them. Our experimental results are in very good agreement with theoretical predictions related to the tested constraints. Our results also show that quantifiers such as $\mathcal {V}$ and $\mathcal {D}$ help not only to quantify, but also to generalize the concept of WPD.

Deterministic Generation of Large Fock States

We present a protocol to deterministically prepare the electromagnetic field in a large photon number state. The field starts in a coherent state and, through resonant interaction with one or few two-level systems, it evolves into a coherently displaced Fock state without any postselection. We show the feasibility of the scheme under realistic parameters. The presented method opens a door to reach Fock states, with n∼100 and optimal fidelities above 70%, blurring the line between macroscopic and quantum states of the field.

Legal abortion in Asturias (Spain) after the 1985 law: sociodemographic characteristics of women applying for abortion

STUDY OBJECTIVE

To describe the use of induced abortion (IA) in Asturias after its legalisation as well as the socio-demographic characteristics of women applying for abortion.

DESIGN AND SETTING

Descriptive study, population-based, using data collected by the regional abortion surveillance system for the period 1988 1994.

MAIN RESULTS

The number of IA and the abortion rate (AR) (10 per 1000 women aged 15-49) have been stable in Asturias during the study period. The highest ARs were found for women in the age group 20-34, for divorced/separated, for women with a higher educational level and for women with only one child. The proportion of pregnancies which ended in abortion was one in four; for teenagers and women over 34 years it was one in two. This proportion was also higher for women not married, students and women with two or more children. Ninety-eight percent of all abortions took place in private clinics, the woman's physical/mental health being the medical indication for these abortions. Abortion was most often performed within eight weeks of gestation (65%). Late abortion ocurred more frequently among teenagers and women of low educational level. Eighteen percent of women had repeated abortions. A high proportion (61%) of women applying for abortion had not used the Family Planning (FP) services in the previous two years; adolescents and women of low educational level had the lowest frequencies of FP use.

CONCLUSIONS

Compared with that of other European countries, the AR in Asturias was intermediate. The results regarding adolescents show the need for evaluation and promotion of sex education and contraceptive programmes. The lower and later use of abortion by women of low educational level shows inequalities that call for specific action.

Depression in three populations in the Basque country--a comparison with Britain

A psychiatric survey in three regions of the Basque Autonomous Community aimed to replicate two British surveys, in London and a rural area of Scotland, investigating both prevalence of psychiatric disorder and its relationship with certain key psychosocial factors. The Spanish rural-urban differences in rates of depression and anxiety closely paralleled the earlier British results. As in Britain, Spanish rural rates of depression were lower among those most integrated into the traditional family ways of life, but in contrast to Britain the urban rates did not vary with social class or the presence of children at home. As in Britain, severe life event and major difficulties were associated with onset of depression, and varied in prevalence and type with degree of integration with the traditional lifestyle. The protective role of intimate confiding with a partner against depressive onset was confirmed among non-churchgoers in Bilbao, but not among churchgoers, while in the rural samples there was only a nonsignificant trend.