Direct observation of number squeezing in an optical lattice

We present an in-situ study of an optical lattice with tunneling and single lattice site resolution. This system provides an important step for realizing a quantum computer. The real-space images show the fluctuations of the atom number in each site. The sub-Poissonian distribution results from the approach to the Mott insulator state, combined with the dynamics of density-dependent losses, which result from the high densities of optical lattice experiments. These losses are clear from the shape of the lattice profile. Furthermore, we find that the lattice is not in the ground state despite the momentum distribution which shows the reciprocal lattice. These effects may well be relevant for other optical lattice experiments, past and future. The lattice beams are derived from a microlens array, resulting in lattice beams which are perfectly stable relative to one another

Recent progress in genetics of aging, senescence and longevity: focusing on cancer-related genes

It is widely believed that aging results from the accumulation of molecular damage, including damage of DNA and mitochondria and accumulation of molecular garbage both inside and outside of the cell. Recently, this paradigm is being replaced by the “hyperfunction theory�, which postulates that aging is caused by activation of signal transduction pathways such as TOR (Target of Rapamycin). These pathways consist of different enzymes, mostly kinases, but also phosphatases, deacetylases, GTPases, and some other molecules that cause overactivation of normal cellular functions. Overactivation of these sensory signal transduction pathways can cause cellular senescence, age-related diseases, including cancer, and shorten life span. Here we review some of the numerous very recent publications on the role of signal transduction molecules in aging and age-related diseases. As was emphasized by the author of the “hyperfunction model�, many (or actually all) of them also play roles in cancer. So these “participants� in pro-aging signaling pathways are actually very well acquainted to cancer researchers. A cancer-related journal such as Oncotarget is the perfect place for publication of such experimental studies, reviews and perspectives, as it can bridge the gap between cancer and aging researchers

Three-Dimensional Spatiotemporal Pulse-Train Solitons

Experimental realization of three-dimensional spatiotemporal solitons, which were proposed several decades ago, is still considered a “grand challenge” in nonlinear science. Here, we present experimental observation of 3D optical spatiotemporal pulse-train solitons. A spatially bright temporally dark pulse-train beam is trapped in a bulk medium that supports two types of nonlinearities: slowly responding saturable self-focusing that collectively self-trap the beam in the transverse directions and fast self-phase modulation that self-localizes each dark notch temporally (longitudinally). This work opens the possibility for experimental investigations of various soliton phenomena, including soliton interaction in 3D, formation of multimode spatiotemporal solitons, and envisioning new entities like partially coherent spatiotemporal solitons

Supplement 1: Ptychographic reconstruction algorithm for frequency-resolved optical gating: super-resolution and supreme robustness

supplementary material Originally published in Optica on 20 December 2016 (optica-3-12-1320

Electrospun Anion-Conducting Ionomer Fibers—Effect of Humidity on Final Properties

Anion-conducting ionomer-based nanofibers mats are prepared by electrospinning (ES) technique. Depending on the relative humidity (RH) during the ES process (RHES), ionomer nanofibers with different morphologies are obtained. The effect of relative humidity on the ionomer nanofibers morphology, ionic conductivity, and water uptake (WU) is studied. A branching effect in the ES fibers found to occur mostly at RHES < 30% is discussed. The anion conductivity and WU of the ionomer electrospun mats prepared at the lowest RHES are found to be higher than in those prepared at higher RHES. This effect can be ascribed to the large diameter of the ionomer fibers, which have a higher WU. Understanding the effect of RH during the ES process on ionomer-based fibers’ properties is critical for the preparation of electrospun fiber mats for specific applications, such as electrochemical devices