Gender trouble and its impact on fertility intentions

It is often an underlying assumption that the new role of women and in general the trend toward a more egalitarian view of the concept of partnership is a main factor behind the low fertility rates in rich countries The aim of this paper is to test the consequences of gender (in)equity on the desire of women and men to have (further) children by using gender inequity as an important category within population science. In our assumptions we want to test whether an unequal distribution of household chores and childcare duties has a negative effect on the desire to have children. Another assumption examines the potential correlation that the perception of (in)equality of women and men in society or the acceptance of government measures to ensure equal rights might have with the desire to have children. The data are derived from the recent Austrian survey Population Policy Acceptance Survey. The assumptions are tested by means of logistic regression analysis. The results show that it is new men who are likely to express a wish for children, rather than those who live in traditional partnership models

Demographic Profile of the Arab Region: Realizing the Demographic Dividend. E/ESCWA/SDD/2016/Technical Paper 3

The demographic transition is a change in patterns of population growth, from high rates of fertility and mortality to low rates of fertility and mortality. At an early stage, this transition leads to a shift in the population’s age composition whereby the number of working-age persons exceeds that of economically dependent persons. More resources are then available for investment in human capital (health and education), physical capital, and economic and social development. This phase is referred to as the demographic dividend or demographic window of opportunity. Its duration varies between countries, and it is affected by various factors such as the speed of fertility decline (the faster the better), and employment and productivity rates. Today, Arab countries are registering declining fertility rates and increases in life expectancy, although at different paces and starting from different levels. They are thus at different stages of the demographic transition and of the window of opportunity. This study, aimed at analysing the demographic changes that Arab countries are undergoing, classes them in four categories: (a) Arab least developed countries (LDCs): Comoros, Djibouti, Mauritania, Somalia, Sudan and Yemen; (b) Gulf Cooperation Council (GCC) members: Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and United Arab Emirates; (c) Mashreq countries: Egypt, Iraq, Jordan, Lebanon, State of Palestine and Syrian Arab Republic; and (d) Maghreb countries: Algeria, Libya, Morocco and Tunisia. It gives an overview of population dynamics and trends in the Arab region and assesses the window of opportunity during which each country could reap the benefits of its changing population structure. Reaping the benefits of the demographic dividend is not automatic and requires an enabling policy environment. The study thus presents four case studies on countries that benefitted from their demographic window of opportunity by implementing sound policies, making recommendations for the Arab region

Evolution in prostheses for sprinters with lower-limb amputation

Depuis une quinzaine d'années, les progrès techniques en appareillage ont été le facteur déterminant de la progression des performances des sportifs amputés de membre inférieur. Pour l'amputé tibial, la prothèse de course comprend un manchon gel et une emboîture solidarisés par un accrochage distal ou un vide virtuel. Par ses qualités dynamiques, le pied en fibre de carbone, garni de pointes, assure des performances remarquables. Pour l'amputé fémoral, équipé des mêmes pieds prothétiques, le genou est à biellettes et à contrôle des phases d'appui et pendulaire. Par rapport au coureur valide, le temps d'appui sur le membre appareillé est raccourci tandis que celui sur le membre sain est allongé. L'asymétrie du sprint de l'amputé tibial est discrète. C'est le travail des extenseurs de hanche qui est la principale compensation au déficit de propulsion dû à l'amputation. Chez l'amputé fémoral, l'absence de genou aggrave l'asymétrie. L'extension totale du genou prothétique, précoce en fin de phase oscillante et persistant pendant toute la phase d'appui, impose une compensation par une augmentation d'extension de la hanche controlatérale. Les transferts de charge de travail entre côté amputé et sain, par l'intermédiaire d'une hyperlordose lombaire, mettent en jeu le bassin, le tronc et les épaules. Les amputés sportifs font progresser la recherche en appareillage. Leurs orthoprothésistes acquièrent avec eux un savoir-faire dont bénéficient leurs patients non-sportifs.For about 15 years, technical advances in prosthetic treatment have been the main factor in the increased performance of athletes with lower-limb amputation. For trans-tibial amputation, the prosthesis for sprinting is composed of a gel liner and a socket joined by a locking or virtual vacuum liner. Because of these dynamic properties, the carbon prosthetic foot equipped with tacks ensures outstanding performance. For trans-femoral amputation, a hydraulic swing and a stance control unit are added to the same prosthesis. In comparison with the able-bodied runner, athletes with amputation have smaller loading times in the prosthetic limb and larger ones in the sound limb. The length of the energy-storing prosthetic foot is determined by the “up-on-the-toes” running gait. The sprinting gait with trans-tibial amputation is almost symmetrical. The hip extensor effort is the main compensation of propulsion reduction with lower-limb amputation. With trans-femoral amputation, the lack of knee increases the asymmetry. The total prosthetic knee extension (early in late-swing phase and lasting during total stance phase) compensates with extension of both hips, especially the opposite one. The amputation and sound limb load transfer with lumbar hyperlordosis concern the pelvis, trunk and shoulders. Because of athletes with amputation, research in prosthetic treatment has progressed. The development of orthotics and prostheses for such athletes has benefited non-athletes with amputation

PHARAO Laser Source Flight Model: Design and Performances

In this paper, we describe the design and the main performances of the PHARAO laser source flight model. PHARAO is a laser cooled cesium clock specially designed for operation in space and the laser source is one of the main sub-systems. The flight model presented in this work is the first remote-controlled laser system designed for spaceborne cold atom manipulation. The main challenges arise from mechanical compatibility with space constraints, which impose a high level of compactness, a low electric power consumption, a wide range of operating temperature and a vacuum environment. We describe the main functions of the laser source and give an overview of the main technologies developed for this instrument. We present some results of the qualification process. The characteristics of the laser source flight model, and their impact on the clock performances, have been verified in operational conditions.Comment: Accepted for publication in Review of Scientific Instrument

Novel mechanism of photoinduced reversible phase transitions in molecule-based magnets

A novel microscopic mechanism of bi-directional structural changes is proposed for the photo-induced magnetic phase transition in Co-Fe Prussian blue analogues on the basis of ab initio quantum chemical cluster calculations. It is shown that the local potential energies of various spin states of Co are sensitive to the number of nearest neighbor Fe vacancies. As a result, the forward and backward structural changes are most readily initiated by excitation of different local regions by different photons. This mechanism suggests an effective strategy to realize photoinduced reversible phase transitions in a general system consisting of two local components.Comment: 4 pages, LaTex, 3 figures, to appear in Phys. Rev. Let

Collective effects in spin-crossover chains with exchange interaction

The collective properties of spin-crossover chains are studied. Spin-crossover compounds contain ions with a low-spin ground state and low lying high-spin excited states and are of interest for molecular memory applications. Some of them naturally form one-dimensional chains. Elastic interaction and Ising exchange interaction are taken into account. The transfer-matrix approach is used to calculate the partition function, the fraction of ions in the high-spin state, the magnetization, susceptibility, etc., exactly. The high-spin-low-spin degree of freedom leads to collective effects not present in simple spin chains. The ground-state phase diagram is mapped out and compared to the case with Heisenberg exchange interaction. The various phases give rise to characteristic behavior at nonzero temperatures, including sharp crossovers between low- and high-temperature regimes. A Curie-Weiss law for the susceptibility is derived and the paramagnetic Curie temperature is calculated. Possible experiments to determine the exchange coupling are discussed.Comment: 9 pages, 13 color figures, published versio

Simian Immunodeficiency Virus Infection of Chimpanzees (Pan troglodytes) Shares Features of Both Pathogenic and Non-pathogenic Lentiviral Infections.

The virus-host relationship in simian immunodeficiency virus (SIV) infected chimpanzees is thought to be different from that found in other SIV infected African primates. However, studies of captive SIVcpz infected chimpanzees are limited. Previously, the natural SIVcpz infection of one chimpanzee, and the experimental infection of six chimpanzees was reported, with limited follow-up. Here, we present a long-term study of these seven animals, with a retrospective re-examination of the early stages of infection. The only clinical signs consistent with AIDS or AIDS associated disease was thrombocytopenia in two cases, associated with the development of anti-platelet antibodies. However, compared to uninfected and HIV-1 infected animals, SIVcpz infected animals had significantly lower levels of peripheral blood CD4+ T-cells. Despite this, levels of T-cell activation in chronic infection were not significantly elevated. In addition, while plasma levels of β2 microglobulin, neopterin and soluble TNF-related apoptosis inducing ligand (sTRAIL) were elevated in acute infection, these markers returned to near-normal levels in chronic infection, reminiscent of immune activation patterns in 'natural host' species. Furthermore, plasma soluble CD14 was not elevated in chronic infection. However, examination of the secondary lymphoid environment revealed persistent changes to the lymphoid structure, including follicular hyperplasia in SIVcpz infected animals. In addition, both SIV and HIV-1 infected chimpanzees showed increased levels of deposition of collagen and increased levels of Mx1 expression in the T-cell zones of the lymph node. The outcome of SIVcpz infection of captive chimpanzees therefore shares features of both non-pathogenic and pathogenic lentivirus infections.This work was supported by the Biotechnology and Biological Sciences Research Council and by the Wellcome Trust.This is the final version of the article. It first appeared from PLOS via http://dx.doi.org/10.1371/journal.ppat.100514

Reticular dysgenesis-associated AK2 protects hematopoietic stem and progenitor cell development from oxidative stress.

Adenylate kinases (AKs) are phosphotransferases that regulate the cellular adenine nucleotide composition and play a critical role in the energy homeostasis of all tissues. The AK2 isoenzyme is expressed in the mitochondrial intermembrane space and is mutated in reticular dysgenesis (RD), a rare form of severe combined immunodeficiency (SCID) in humans. RD is characterized by a maturation arrest in the myeloid and lymphoid lineages, leading to early onset, recurrent, and overwhelming infections. To gain insight into the pathophysiology of RD, we studied the effects of AK2 deficiency using the zebrafish model and induced pluripotent stem cells (iPSCs) derived from fibroblasts of an RD patient. In zebrafish, Ak2 deficiency affected hematopoietic stem and progenitor cell (HSPC) development with increased oxidative stress and apoptosis. AK2-deficient iPSCs recapitulated the characteristic myeloid maturation arrest at the promyelocyte stage and demonstrated an increased AMP/ADP ratio, indicative of an energy-depleted adenine nucleotide profile. Antioxidant treatment rescued the hematopoietic phenotypes in vivo in ak2 mutant zebrafish and restored differentiation of AK2-deficient iPSCs into mature granulocytes. Our results link hematopoietic cell fate in AK2 deficiency to cellular energy depletion and increased oxidative stress. This points to the potential use of antioxidants as a supportive therapeutic modality for patients with RD