Mode-specific directional emission from hybridized particle-on-a-film plasmons

We investigate the electromagnetic interaction between a gold nanoparticle and a thin gold film on a glass substrate. The coupling between the particle plasmons and the surface plasmon polaritons of the film leads to the formation of two localized hybrid modes, one low-energy. film-like. plasmon and one high-energy plasmon dominated by the nanoparticle. We find that the two modes have completely different directional scattering patterns on the glass side of the film. The high-energy mode displays a characteristic dipole emission pattern while the low-energy mode sends out a substantial part of its radiation in directions parallel to the particle dipole moment. The relative strength of the two radiation patterns vary strongly with the distance between the particle and the film, as determined by the degree of particle-film hybridization

Plasmon-Interband Coupling in Nickel Nanoantennas

Plasmonic excitations are usually attributed to the free electron response at visible frequencies in the classic plasmonic metals Au and Ag. However, the vast majority of metals exhibit spectrally localized interband transitions or broad interband transition backgrounds in the energy range of interest for nanoplasmonics. Nevertheless, the interaction of interband transitions with localized plasmons in optical nanoantennas has hitherto received relatively little attention, probably because interband transitions are regarded as highly unwanted due to their strong damping effect on the localized plasmons. However, with an increasing number of metals (beyond Au and Ag) being considered for nanoplasmonic applications such as hydrogen sensing (Pd), UV-SERS (Al), or magnetoplasmonics (Ni, Fe, Co), a deeper conceptual understanding of the interactions between a localized plasmon mode and an interband transition is very important. Here, as a generic example, we examine the interaction of a localized (in energy space) interband transition with spectrally tunable localized plasmonic excitations and unearth the underlying physics in a phenomenological approach for the case of Ni disk nanoantennas. We find that plasmon interband interactions can be understood in the classical picture of two coupled harmonic oscillators, exhibiting the typical energy anticrossing fingerprint of a coupled system approaching the strong-coupling regime

Opposing Effects of Omega-3 and Omega-6 Long Chain Polyunsaturated Fatty Acids on the Expression of Lipogenic Genes in Omental and Retroperitoneal Adipose Depots in the Rat

This study aimed to determine the effect of varying dietary intake of the major n-3 PUFA in human diets, α-linolenic acid (ALA; 18 : 3n-3), on expression of lipogenic genes in adipose tissue. Rats were fed diets containing from 0.095%en to 6.3%en ALA and a constant n-6 PUFA level for 3 weeks. Samples from distinct adipose depots (omental and retroperitoneal) were collected and mRNA expression of the pro-lipogenic transcription factors Sterol-Retinoid-Element-Binding-Protein1c (SREBP1c) and Peroxisome Proliferator Activated Receptor-γ (PPARγ), lipogenic enzymes Sterol-coenzyme Desaturase1 (SCD-1), Fatty Acid Synthase (FAS), lipoprotein lipase (LPL) and glycerol-3-phosphate dehydrogenase (G3PDH) and adipokines leptin and adiponectin determined by qRT-PCR. Increasing dietary ALA content resulted in altered expression of SREBP1c, FAS and G3PDH mRNA in both adipose depots. SREBP1c mRNA expression was related directly to n-6 PUFA concentrations (omental, r2 = .71; P < .001; Retroperitoneal, r2 = .20; P < .002), and inversely to n-3 PUFA concentrations (omental, r2 = .59; P < .001; Retroperitoneal, r2 = .19; P < .005) independent of diet. The relationship between total n-6 PUFA and SREBP1c mRNA expression persisted when the effects of n-3 PUFA were controlled for. Altering red blood cell concentrations of n-3 PUFA is thus associated with altered expression of lipogenic genes in a depot-specific manner and this effect is modulated by prevailing n-6 PUFA concentrations

Aerobic capacity and respiratory patterns are better in recreational basketball-engaged university students than age-matched untrained males

Study aim: To asses and compare the aerobic capacity and respiratory parameters in recreational basketball-engaged university students with age-matched untrained young adults. Material and methods: A total of 30 subjects were selected to took part in the study based on recreational-basketball activity level and were assigned to a basketball (BG: N = 15, age 22.86 ± 1.35 yrs., body height 185.07 ± 5.95 cm, body weight 81.21 ± 6.15 kg) and untrained group (UG: N = 15, age 22.60 ± 1.50 yrs., body height 181.53 ± 6.11 cm, body weight 76.89 ± 7.30 kg). Inspiratory vital capacity (IVC), forced expiration volume (FEV1), FEV1/IVC ratio, maximal oxygen consumption (VO2max), ventilatory threshold (VO2VT) and time to exhaustion, were measured in all subjects. Student T-test for independent Sample and Cohen's d as the measure of the effect size were calculated. Results: Recreational basketball-engaged students (EG) reached significantly greater IVC (t = 7.240, p &lt; 0.001, d = 1.854), FEV1 (t = 10.852, p &lt; 0.001, d = 2.834), FEV1/IVC ratio (t = 6.370, p &lt; 0.001, d = 3.920), maximal oxygen consumption (t = 9.039, p &lt; 0.001, d = 3.310), ventilatory threshold (t = 9.859, p &lt; 0.001, d = 3.607) and time to exhaustion (t = 12.361, p &lt; 0.001, d = 4.515) compared to UG. Conclusions: Long-term exposure to recreational basketball leads to adaptive changes in aerobic and respiratory parameters in male university students

Electrostatic charging of jumping droplets

With the broad interest in and development of superhydrophobic surfaces for self-cleaning, condensation heat transfer enhancement and anti-icing applications, more detailed insights on droplet interactions on these surfaces have emerged. Specifically, when two droplets coalesce, they can spontaneously jump away from a superhydrophobic surface due to the release of excess surface energy. Here we show that jumping droplets gain a net positive charge that causes them to repel each other mid-flight. We used electric fields to quantify the charge on the droplets and identified the mechanism for the charge accumulation, which is associated with the formation of the electric double layer at the droplet–surface interface. The observation of droplet charge accumulation provides insight into jumping droplet physics as well as processes involving charged liquid droplets. Furthermore, this work is a starting point for more advanced approaches for enhancing jumping droplet surface performance by using external electric fields to control droplet jumping.United States. Dept. of Energy. Office of Basic Energy Sciences (Solid-State Solar-Thermal Energy Conversion Center Award DE-FG02-09ER46577)United States. Office of Naval ResearchNational Science Foundation (U.S.) (Major Research Instrumentation Grant for Rapid Response Research (MRI- RAPID))National Science Foundation (U.S.) (Award ECS-0335765)National Science Foundation (U.S.). Graduate Research Fellowship Program (Grant 1122374

Naked mole-rats have distinctive cardiometabolic and genetic adaptations to their underground low-oxygen lifestyles.

The naked mole-rat Heterocephalus glaber is a eusocial mammal exhibiting extreme longevity (37-year lifespan), extraordinary resistance to hypoxia and absence of cardiovascular disease. To identify the mechanisms behind these exceptional traits, metabolomics and RNAseq of cardiac tissue from naked mole-rats was compared to other African mole-rat genera (Cape, Cape dune, Common, Natal, Mahali, Highveld and Damaraland mole-rats) and evolutionarily divergent mammals (Hottentot golden mole and C57/BL6 mouse). We identify metabolic and genetic adaptations unique to naked mole-rats including elevated glycogen, thus enabling glycolytic ATP generation during cardiac ischemia. Elevated normoxic expression of HIF-1α is observed while downstream hypoxia responsive-genes are down-regulated, suggesting adaptation to low oxygen environments. Naked mole-rat hearts show reduced succinate levels during ischemia compared to C57/BL6 mouse and negligible tissue damage following ischemia-reperfusion injury. These evolutionary traits reflect adaptation to a unique hypoxic and eusocial lifestyle that collectively may contribute to their longevity and health span

In vivo effects of interleukin-17 on haematopoietic cells and cytokine release in normal mice

In order to gain more insight into mechanisms operating on the haematopoietic activity of the T-cell-derived cytokine, interleukin-17 (IL-17) and target cells that first respond to its action in vivo, the influence of a single intravenous injection of recombinant mouse IL-17 on bone marrow progenitors, further morphologically recognizable cells and peripheral blood cells was assessed in normal mice up to 72 h after treatment. Simultaneously, the release of IL-6, IL-10, IGF-I, IFN-gamma and NO by bone marrow cells was determined. Results showed that, in bone marrow, IL-17 did not affect granulocyte-macrophage (CFU-GM) progenitors, but induced a persistant increase in the number of morphologically recognizable proliferative granulocytes (PG) up to 48 h after treatment. The number of immature erythroid (BFU-E) progenitors was increased at 48 h, while the number of mature erythroid (CFU-E) progenitors was decreased up to 48 h. In peripheral blood, white blood cells were increased 6 h after treatment, mainly because of the increase in the number of lymphocytes. IL-17 also increased IL-6 release and NO production 6 h after administration. Additional in vitro assessment on bone marrow highly enriched Lin(-) progenitor cells, demonstrated a slightly enhancing effect of IL-17 on CFU-GM and no influence on BFU-E, suggesting the importance of bone marrow accessory cells and secondary induced cytokines for IL-17 mediated effects on progenitor cells. Taken together, these results demonstrate that in vivo IL-17 affects both granulocytic and erythroid lineages, with more mature haematopoietic progenitors responding first to its action. The opposite effects exerted on PG and CFU-E found at the same time indicate that IL-17, as a component of a regulatory network, is able to intervene in mechanisms that shift haematopoiesis from the erythroid to the granulocytic lineage