Optimal read/write memory system components

Two holographic data storage and display systems, voltage gradient ionization system, and linear strain manipulation system are discussed in terms of creating fast, high bit density, storage device. Components described include: novel mounting fixture for photoplastic arrays; corona discharge device; and block data composer

Tunable biohybrid hydrogels from coacervation of hyaluronic acid and PEO‐based block copolymers

Accurately tuning the macroscopic properties of biopolymer‐based hydrogels remains challenging due to the ill‐defined molecular architecture of the natural building blocks. Here, we report a biohybrid coacervate hydrogel, combining the biocompatibility and biodegradability of naturally occurring hyaluronic acid (HA) with the tunability of a synthetic polyethylene oxide (PEO) ‐based ABA‐triblock copolymer. Coacervation of the cationic ammonium or guanidinium‐functionalized copolymer A‐blocks with the anionic HA leads to hydrogel formation. Both mechanical properties and water content of the self‐healing hydrogels can be controlled independently by altering the copolymer structure. By controlling the strength of the interaction between the polymer network and small‐molecule cargo, both release rate and maximum release are controlled. Finally, we show that coacervation of HA and the triblock copolymer leads to increased biostability upon exposure to hyaluronidase. We envision that noncovalent crosslinking of HA hydrogels through coacervation is an attractive strategy for the facile synthesis of tunable hydrogels for biomedical applications

Magnetic field--induced modification of selection rules for Rb D2_2 line monitored by selective reflection from a vapor nanocell

Magnetic field-induced giant modification of the probabilities of five transitions of $5S_{1/2}, F_g=2 \rightarrow 5P_{3/2}, F_e=4$ of $^{85}$Rb and three transitions of $5S_{1/2}, F_g=1 \rightarrow 5P_{3/2}, F_e=3$ of $^{87}$Rb forbidden by selection rules for zero magnetic field has been observed experimentally and described theoretically for the first time. For the case of excitation with circularly-polarized ($\sigma^+$) laser radiation, the probability of $F_g=2, ~m_F=-2 \rightarrow F_e=4, ~m_F=-1$ transition becomes the largest among the seventeen transitions of $^{85}$Rb $F_g=2 \rightarrow F_e=1,2,3,4$ group, and the probability of $F_g=1,~m_F=-1 \rightarrow F_e=3,~m_F=0$ transition becomes the largest among the nine transitions of $^{87}$Rb $F_g=1 \rightarrow F_e=0,1,2,3$ group, in a wide range of magnetic field 200 -- 1000 G. Complete frequency separation of individual Zeeman components was obtained by implementation of derivative selective reflection technique with a 300 nm-thick nanocell filled with Rb, allowing formation of narrow optical resonances. Possible applications are addressed. The theoretical model is perfectly consistent with the experimental results.Comment: 6 pages, 5 figure

Effect of culture in simulated microgravity on the development of mouse embryonic testes

BACKGROUND All known organisms develop and evolve in the presence of gravitational force, and it is evident that gravity has a significant influence on organism physiology and development. Microgravity is known to affect gene expression, enzyme activity, cytoskeleton organization, mitotic proliferation and intracellular signaling. OBJECTIVES: The aim of the present study was to study some aspects of the development in vitro of mouse embryonic testes in simulated microgravity. MATERIAL AND METHODS: Testes from mouse embryos (12.5-16.5 days post coitum, d.p.c.) were cultured in simulated microgravity and standard static culture conditions. The microgravity condition was provided by a Rotary Cell Culture System (RWV) bioreactor, an apparatus designated for 3D tissue and small organ cultures. After 48 h of the culture in the RWV, testis morphology and size was evaluated. RESULTS: The first observation was that the culture in the RWV bioreactor had a beneficial effect on the testis growth and on the survival of germ cells in comparison to static 2D culture methods. Moreover, we found, that RWV culture caused disorganization the gonadal tissues, namely of the testis cords. CONCLUSIONS: The results suggest that the maintenance of testis cord could be sensitive to microgravity. We hypothesize that while the effect on testis growth is due to a better nutrient and oxygen supply, the testis cord's disorganization might depend on the microgravity conditions simulated by the bioreactor. Considering the complexity of the processes involved in the formation of the testis cords and their dynamic changes during the embryo fetal period, further studies are needed to identify the causes of such effect

Modifications of comet materials by the sublimation process: Results from simulation experiments

An active comet like comet Halley loses by sublimation a surface layer of the order of 1 m thickness per perihelion passage. In situ measurements show that water ice is the main constituent which contributes to the gas emission although even more volatile species (CO, NH3, CH4, CO2 etc.) have been identified. Dust particles which were embedded in the ices are carried by the sublimating gases. Measurements of the chemical composition of cometary grains indicate that they are composed of silicates of approximate chondritic composition and refractory carbonaceous material. Comet simulation experiments show that significant modifications of cometary materials occur due to sublimation process in near surface layers which have to be taken into account in order to derive the original state of the material

Slip rate on the Dead Sea transform fault in northern Araba valley (Jordan)

The Araba valley lies between the southern tip of the Dead Sea and the Gulf of Aqaba. This depression, blanketed with alluvial and lacustrine deposits, is cut along its entire length by the Dead Sea fault. In many places the fault is well defined by scarps, and evidence for left-lateral strike-slip faulting is abundant. The slip rate on the fault can be constrained from dated geomorphic features displaced by the fault. A large fan at the mouth of Wadi Dahal has been displaced by about 500 m since the bulk of the fanglomerates were deposited 77–140 kyr ago, as dated from cosmogenic isotope analysis (^(10)Be in chert) of pebbles collected on the fan surface and from the age of transgressive lacustrine sediments capping the fan. Holocene alluvial surfaces are also clearly offset. By correlation with similar surfaces along the Dead Sea lake margin, we propose a chronology for their emplacement. Taken together, our observations suggest an average slip rate over the Late Pleistocene of between 2 and 6 mm yr^(−1), with a preferred value of 4 mm yr^(−1). This slip rate is shown to be consistent with other constraints on the kinematics of the Arabian plate, assuming a rotation rate of about 0.396° Myr^(−1) around a pole at 31.1°N, 26.7°E relative to Africa

Spontaneous and deliberate future thinking: A dual process account

© 2019 Springer Nature.This is the final published version of an article published in Psychological Research, licensed under a Creative Commons Attri-bution 4.0 International License. Available online at: https://doi.org/10.1007/s00426-019-01262-7.In this article, we address an apparent paradox in the literature on mental time travel and mind-wandering: How is it possible that future thinking is both constructive, yet often experienced as occurring spontaneously? We identify and describe two ‘routes’ whereby episodic future thoughts are brought to consciousness, with each of the ‘routes’ being associated with separable cognitive processes and functions. Voluntary future thinking relies on controlled, deliberate and slow cognitive processing. The other, termed involuntary or spontaneous future thinking, relies on automatic processes that allows ‘fully-fledged’ episodic future thoughts to freely come to mind, often triggered by internal or external cues. To unravel the paradox, we propose that the majority of spontaneous future thoughts are ‘pre-made’ (i.e., each spontaneous future thought is a re-iteration of a previously constructed future event), and therefore based on simple, well-understood, memory processes. We also propose that the pre-made hypothesis explains why spontaneous future thoughts occur rapidly, are similar to involuntary memories, and predominantly about upcoming tasks and goals. We also raise the possibility that spontaneous future thinking is the default mode of imagining the future. This dual process approach complements and extends standard theoretical approaches that emphasise constructive simulation, and outlines novel opportunities for researchers examining voluntary and spontaneous forms of future thinking.Peer reviewe

Riociguat: Mode of action and clinical development in pulmonary hypertension

Pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) are progressive and debilitating diseases characterized by gradual obstruction of the pulmonary vasculature, leading to elevated pulmonary artery pressure and increased pulmonary vascular resistance. If untreated, they can result in death due to right heart failure. Riociguat is a novel soluble guanylate cyclase (sGC) stimulator that is approved for the treatment of PAH and CTEPH. Here we describe in detail the role of the nitric oxide-sGC-cyclic guanosine monophosphate (cGMP) signaling pathway in the pathogenesis of PAH and CTEPH, and the mode of action of riociguat. We also review the preclinical data associated with the development of riociguat, along with the efficacy and safety data of riociguat from initial clinical trials and the pivotal Phase III randomized clinical trials in PAH and CTEPH

Photoinduced IR absorption in (La(1-x)Sr(x)Mn)(1-\delta)O3: changes of the anti-Jahn-Teller polaron binding energy with doping

Photoinduced IR absorption was measured in (La(1-x)Sr(x)Mn)(1-\delta)O3. A midinfrared peak centered at ~ 5000 cm$^{-1}$ was observed in the x=0 antiferromagnetic sample. The peak diminishes and softens as hole doping is increased. The origin of the photoinduced absorption peak is atributted to the photon assisted hopping of anti-Jahn-Teller polarons formed by photoexcited charge carriers, whose binding energy decreases with increasing hole doping. The shape of the peak indicates that the polarons are small.Comment: 5 pages, 3 figures, submitted to PR