Daily activities and survival at older ages

This study tested the hypothesis that time spent on regenerative (e.g., resting), productive (e.g., housework), and consumptive activities (e.g., meeting friends) is associated with survival in persons aged 70 and older. An observational study with semi-annual mortality follow-ups was carried out in the former West Berlin, Germany. The sample was stratified by age and sex and consisted of 473 persons aged 70 to 103 years. Study participants lived in the community as well as in institutions. Activity measures were assessed in 1990-1993 by structured interviews in the participants´ homes. Cox regression was used to model survival from time of interview. The main outcome measure was survival on 3 February 2000. Consumptive activities were related to survival (relative risk = 0.76, 95% confidence interval 0.58 to 1.00) after several confounding factors were controlled for. There were indications that the greatest survival benefit is achieved with a medium amount of time devoted to consumptive activities. Our results support the idea that daily activities are linked to survival via a psychosocial pathway, which might involve perceived quality of life. Consumptive activities (e.g., meeting friends, reading a novel) may contribute considerably to maintaining health and achieving longevity, because they are performed on a daily basis and their effects may accumulate over the life course.

Nanolithography with metastable helium atoms in a high-power standing-wave light field

We have created periodic nanoscale structures in a gold substrate with a lithography process using metastable triplet helium atoms that damage a hydrofobic resist layer on top of the substrate. A beam of metastable helium atoms is transversely cooled and guided through an intense standing-wave light field. Compared to commonly used low-power optical masks, a high-power light field (saturation parameter of 10E7) increases the confinement of the atoms in the standing-wave considerably, and makes the alignment of the experimental setup less critical. Due to the high internal energy of the metastable helium atoms (20 eV), a dose of only one atom per resist molecule is required. With an exposure time of only eight minutes, parallel lines with a separation of 542 nm and a width of 100 nm (1/11th of the wavelength used for the optical mask) are created.Comment: 5 pages, 5 figure

A new magnetic field dependence of Landau levels on a graphene like structure

We consider a tight-binding model on the honeycomb lattice in a magnetic field. For special values of the hopping integrals, the dispersion relation is linear in one direction and quadratic in the other. We find that, in this case, the energy of the Landau levels varies with the field B as E_n(B) ~ [(n+\gamma)B]^{2/3}. This result is obtained from the low-field study of the tight-binding spectrum on the honeycomb lattice in a magnetic field (Hofstadter spectrum) as well as from a calculation in the continuum approximation at low field. The latter links the new spectrum to the one of a modified quartic oscillator. The obtained value $\gamma=1/2$ is found to result from the cancellation of a Berry phase.Comment: 4 pages, 4 figure

Atom lithography with two-dimensional optical masks

With a two-dimensional (2D) optical mask, nanoscale patterns are created for the first time in an atom lithography process using metastable helium atoms. The internal energy of the atoms is used to locally damage a hydrofobic resist layer, which is removed in a wet etching process. Experiments have been performed with several polarizations for the optical mask, resulting in different intensity patterns, and corresponding nanoscale structures. The results for a linear polarized light field show an array of holes with a diameter of 260 nm, in agreement with a computed pattern. With a circularly polarized light field a line pattern is observed with a spacing of 766 nm. Simulations taking into account many possible experimental imperfections can not explain this pattern.Comment: 5 pages, 4 figure

Re-Orienting Planning Practice

This commentary reflects on the articles in the thematic issue on queering urban planning and municipal governance and the ways that they suggest that planning practice must be re-oriented to be more inclusive and incorporate more insurgent perspectives. Planning practice is susceptible to capture by neo-liberal corporate interests that marginalize vulnerable queer populations. More insurgent planning approaches are needed to resist the corporate take-over of queer spaces by empowering the voices of LGBTQ+ people

Uterine NK cells are critical in shaping DC immunogenic functions compatible with pregnancy progression.

Dendritic cell (DC) and natural killer (NK) cell interactions are important for the regulation of innate and adaptive immunity, but their relevance during early pregnancy remains elusive. Using two different strategies to manipulate the frequency of NK cells and DC during gestation, we investigated their relative impact on the decidualization process and on angiogenic responses that characterize murine implantation. Manipulation of the frequency of NK cells, DC or both lead to a defective decidual response characterized by decreased proliferation and differentiation of stromal cells. Whereas no detrimental effects were evident upon expansion of DC, NK cell ablation in such expanded DC mice severely compromised decidual development and led to early pregnancy loss. Pregnancy failure in these mice was associated with an unbalanced production of anti-angiogenic signals and most notably, with increased expression of genes related to inflammation and immunogenic activation of DC. Thus, NK cells appear to play an important role counteracting potential anomalies raised by DC expansion and overactivity in the decidua, becoming critical for normal pregnancy progression

Numerical simulations on the motion of atoms travelling through a standing-wave light field

The motion of metastable helium atoms travelling through a standing light wave is investigated with a semi-classical numerical model. The results of a calculation including the velocity dependence of the dipole force are compared with those of the commonly used approach, which assumes a conservative dipole force. The comparison is made for two atom guiding regimes that can be used for the production of nanostructure arrays; a low power regime, where the atoms are focused in a standing wave by the dipole force, and a higher power regime, in which the atoms channel along the potential minima of the light field. In the low power regime the differences between the two models are negligible and both models show that, for lithography purposes, pattern widths of 150 nm can be achieved. In the high power channelling regime the conservative force model, predicting 100 nm features, is shown to break down. The model that incorporates velocity dependence, resulting in a structure size of 40 nm, remains valid, as demonstrated by a comparison with quantum Monte-Carlo wavefunction calculations.Comment: 9 pages, 4 figure

A route to sub-diffraction-limited CARS Microscopy

We theoretically investigate a scheme to obtain sub-diffraction-limited resolution in coherent anti-Stokes Raman scattering (CARS) microscopy. We find using density matrix calculations that the rise of vibrational (Raman) coherence can be strongly suppressed, and thereby the emission of CARS signals can be significantly reduced, when pre-populating the corresponding vibrational state through an incoherent process. The effectiveness of pre-populating the vibrational state of interest is investigated by considering the excitation of a neighbouring vibrational (control) state through an intense, mid-infrared control laser. We observe that, similar to the processes employed in stimulated emission depletion microscopy, the CARS signal exhibits saturation behaviour if the transition rate between the vibrational and the control state is large. Our approach opens up the possibility of achieving chemically selectivity sub-diffraction-limited spatially resolved imaging

Grandparental investment facilitates harmonization of work and family in employed parents: A lifespan psychological perspective

The target article emphasizes the need to identify psychological mechanisms underlying grandparental investment, particularly in low-risk family contexts. We extend this approach by addressing the changing demands of balancing work and family in low-risk families. Taking a lifespan psychological perspective, we identify additional motivators and potential benefits of grandparental investment for grandparents themselves and for subsequent generation