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The influence of mating mind-sets on brand extension evaluation
No full textPrior research has identified several factors that influence brand extension evaluations. Extending this research, the authors suggest that external, situational factors can have an important influence on brand extension evaluations. This research focuses on mating mind-sets (i.e., thinking about a mate), which consumers commonly experience. Specifically, the authors propose that mating mind-sets triggered by the external situation can influence brand extension evaluations, particularly for men. Mating mind-sets induce male consumers (but not female consumers) to engage in relational processing, increasing fit perceptions and evaluations for moderately dissimilar brand extensions. These differences are more likely to emerge when a short-term mating mind-set is primed (vs. a long-term mating mind-set). Furthermore, using prestige brands (vs. functional brands) reduces the gap between men and women. In addition, subbrand architecture (vs. direct brand architecture) boosts the evaluations of female consumers but decreases those of male consumers. The authors find that the effects of mating mind-sets on brand extension evaluation are driven by male consumers' need to express creativity
Ship-borne LF-VLF oceanic lightning observations and modeling
No full textApproximately 90% of natural lightning occurs over land, but recent observations, using Global Lightning Detection (GLD360) geolocation peak current estimates and satellite optical data, suggested that cloud-to-ground flashes are on average stronger over the ocean. We present initial statistics from a novel experiment using a Low Frequency (LF) magnetic field receiver system installed aboard the National Oceanic Atmospheric Agency (NOAA) Ronald W. Brown research vessel that allowed the detection of impulsive radio emissions from deep-oceanic discharges at short distances. Thousands of LF waveforms were recorded, facilitating the comparison of oceanic waveforms to their land counterparts. A computationally efficient electromagnetic radiation model that accounts for propagation over lossy and curved ground is constructed and compared with previously published models. We include the effects of Earth curvature on LF ground wave propagation and quantify the effects of channel-base current risetime, channel-base current falltime, and return stroke speed on the radiated LF waveforms observed at a given distance. We compare simulation results to data and conclude that previously reported larger GLD360 peak current estimates over the ocean are unlikely to fully result from differences in channel-base current risetime, falltime, or return stroke speed between ocean and land flashes
Global occurrence rate of elves and ionospheric heating due to cloud-to-ground lightning
No full textWe present ground-based observations of elves made using an optical free-running photometer along with VLF/LF observations of the lightning electromagnetic pulse (EMP) magnetic field. We use these experimental observations to investigate the properties of the lightning return stroke that control the production of optical elve emissions. Two summers of data containing observations of over 600 elves along with the LF magnetic field of the associated lightning are analyzed. By training a classifier on features of the EMP ground wave, we find that we are able to accurately predict whether or not a stroke produced an elve. We find that the peak current of the causative discharge predicts elve production with 90% accuracy. Further, we find that the production probability of elves as a function of peak current fits a linear regression, with a 50% elve probability for peak currents of 88kA. We use this finding along with global data from the GLD360 lightning geolocation network to extrapolate the global elve production rate; we show that approximate to 0.8% of all cloud-to-ground lightning discharges produce elves. Finally, using GLD360 data and a numerical model of the lightning EMP, we estimate the total amount of ionospheric heating due to lightning, amounting to approximately 2MW of continuous power dissipated globally in the lower ionosphere
Excitation of silicon microspheres resonances with Femtosecond laser fabricated glass waveguides
No full textOptical waveguides were fabricated with femtosecond pulsed lasers on glass and characterized by transmission measurements. Glass waveguides were later used for excitation of the whispering gallery modes in a silicon microsphere. The coupling between the silicon microsphere and the femtosecond laser inscribed optical waveguide was simulated in both 90 degrees elastic scattering and 0 degrees transmission spectra. The silicon microsphere whispering gallery modes are available for both in the transverse electric and transverse magnetic polarizations with a spectral mode spacing of 0.25 nm. Optical resonances on silicon microsphere integrated with femtosecond laser written optical waveguides may lead to future quantum optical communication devices
Periostin and tumor-stroma interactions in non-small cell lung cancer
No full textNon-small cell lung cancer (NSCLC) is one of the leading causes of cancer-associated mortality globally. Interactions of the cancer cells with the tumor microenvironment are essential carcinogenic features for the majority of solid tumors, such as pancreatic cancer. The present study investigated the role of stromal activation in NSCLC and analyzed the surgical specimens of 93 patients by immunohistochemistry with regard to periostin (an extracellular matrix protein), -smooth muscle actin (-SMA; a marker of myofibroblasts) and cluster of differentiation 31 (CD31; a marker of endothelial cells), and the activated stroma index. There was a trend towards reduced overall survival for patients with high periostin expression (hazard ratio, 1.80; 95% confidence interval, 0.99-3.27; P=0.050). No significant correlations with overall survival were identified for -SMA (P=0.930), CD31 (P=0.923), collagen (P=0.441) or the activated stroma index (P=0.706). In a multivariable analysis, the histological tumor subtype, tumor stage, lymph node involvement and resection status were independent prognostic factors in NSCLC, but none of the investigated immunohistochemical markers were prognostic factors. Thus, the tumor microenvironment and stroma activation did not prove to be of prognostic relevance for lung cancer, as it has been previously described for pancreatic cancer. Other markers of the microenvironment of NSCLC may be of higher prognostic value, pointing towards tumor-type specific effects
Transmitter-induced modulation of subionospheric VLF signals: Ionospheric heating rather than electron precipitation
No full textThe controlled keying of ground-based VLF transmitters with periodic on/off sequences allows the detection of weak but measurable cross-modulation effects on other subionospheric VLF probe signals used for VLF remote sensing. In this paper, we reexamine previously published and additional cases of such events and determine that the initial interpretations of such cross modulation as being due to electron precipitation is likely incorrect. Rather, such events appear to be fully consistent with ionospheric heating caused by the keyed signal, even when the probe VLF signal path lies thousands of kilometers from the heating VLF transmitter. The 21.4 kHz transmitter NPM located in Lualualei, Hawaii, is keyed on/off in periodic sequences, and that same periodicity is observed on the subionospherically propagating probe signal generated by the 24.8 kHz transmitter NLK of Jim Creek, Washington. Previous initial conclusions published for these experiments do not hold under detailed review due to the lack of discernible onset delay and lag time in the observed perturbations, which eliminates transmitter-induced precipitation of electron radiation as a possible cause. Detailed testing of the receiver shows instrumental cross-modulation to not be a concern in these observations. It is thus concluded that the observed perturbations, despite occurring on a probe signal pathway that is 1750 km away from NPM at its point of closest approach, are due to direct ionospheric heating by the keyed VLF transmitter NPM. Results indicate that the VLF transmitter may affect the overlying ionosphere over much larger lateral regions than previously believed
Activated leukocyte cell adhesion molecule regulates the interaction between pancreatic cancer cells and stellate cells
No full textActivated leukocyte cell adhesion molecule (ALCAM/CD166) is a transmembrane glycoprotein that is involved in tumor progression and metastasis. In the present study, the expression and functional role of ALCAM in pancreatic cancer cells and pancreatic stellate cells (PSCs) was investigated. Tissue specimens were obtained from patients with pancreatic ductal adenocarcinoma (n=56) or chronic pancreatitis (CP; n=10), who underwent pancreatic resection, and from normal pancreatic tissue samples (n=10). Immunohistochemistry was used to analyze the localization and expression of ALCAM in pancreatic tissues. Subsequently, reverse transcription-quantitative polymerase chain reaction and immunoblotting were applied to assess the expression of ALCAM in pancreatic cancer Panc-1 and T3M4 cells, as well as in PSCs. An enzyme-linked immunosorbent assay was used to measure ALCAM levels in cell culture medium stimulated by hypoxia, tumor necrosis factor (TNF)- and transforming growth factor-. Silencing of ALCAM was performed using ALCAM small interfering (si)RNA and immunocytochemistry was used to analyze the inhibition efficiency. An invasion assay and a cell interaction assay were performed to assess the invasive ability and co-cultured adhesive potential of Panc-1 and T3M4 cells, as well as PSCs. Histologically, ALCAM expression was generally weak or absent in pancreatic cancer cells, but was markedly upregulated in PSCs in pancreatic cancer tissues. ALCAM was highly expressed in PSCs from CP tissues and PSCs surrounding pancreatic intraepithelial neoplasias, as well as in pancreatic cancer cells. ALCAM mRNA was highly expressed in PSCs, with a low to moderate expression in T3M4 and Panc-1 cells. Similar to the mRNA expression, immunoblotting demonstrated that ALCAM protein levels were high in PSCs and T3M4 cells, but low in Panc-1 cells. The expression of TNF- increased, while hypoxia decreased the secretion of ALCAM in pancreatic cancer Panc-1 and T3M4 cells, and also in PSCs. Silencing of ALCAM by siRNA revealed no significant alteration in the invasion of pancreatic cancer cells, however, it inhibited the invasive ability of PSCs, and decreased the interaction between Panc-1 cells and PSCs. In conclusion, ALCAM is upregulated in PSCs of pancreatic cancer tissues, suggesting a potential role of ALCAM in regulating pancreatic cancer cell-PSC interactions
Large spectral tuning of liquid microdroplets by local heating with a focused infrared laser
No full textLarge deformations can easily be introduced in liquid microdroplets by applying relatively small external forces or controlling the evaporation/condensation kinetics. This makes liquid microdroplets attractive to serve as the building blocks of largely tunable optical switches or filters that are essential in optical communication systems based on wavelength division multiplexing. Solid optical microcavities have not found large use in these applications, mainly due to their rigid nature. The fact that liquid microdroplets are low-cost and disposable can also prove to be important in mass production of these photonic devices. Here, we show that local heating with an infrared laser can be used to largely tune the whispering gallery modes (WGMs) of water/glycerol or salty water microdroplets standing on a superhydrophobic surface. In the scheme presented, a liquid microdroplet kept in a humidity chamber is stabilized on a superhydrophobic surface, and an infrared laser beam is focused near tire center of the microdroplet. As a, result of the local treating, the temperature of the liquid microdroplet increases, and the water content in the liquid microdroplet evaporates until a new equilibrium is reached. At the new equilibrium state, the non-volatile component, (i.e. glycerol or salt) attains a higher concentration in the liquid microdroplet. We report tunability over large spectral ranges up to 30 run at around 590 nm. For salty water microdroplets the reported spectral timing mechanism is almost fully reversible, while for tire case of glycerol/water microdroplets the spectral timing mechanism can be made highly reversible when the chamber is saturated with glycerol vapor and the relative water humidity approaches unity
Silicon microspheres for integrated photonics - art. no. 647606
No full textWe have experimentally studied the electrical and optical properties of a silicon microsphere with a radius of 500 microns and a refractive index of 3.48 in the near-infrared. The silicon microsphere shows an MSM Schottky diode behavior. The morphology dependent resonances are spaced by 0.2 nm, which correlates well with the estimated mode spacing. The silicon microsphere heralds the way for a novel family of active microphotonic devices
Diffraction grating based optical readout for thermal imaging
No full textThe thermal sensor system presented in this paper is based on the mechanical bending due to the incident IR radiation. A diffraction grating is embedded under each pixel to facilitate optical readout. Typically the first diffraction order is used to monitor the sub-micron mechanical displacement with sub-nanometer precision. In this work; two different optical readout systems based on diffraction gratings are analyzed. First setup employs a conventional 4f optical system. In this one-to-one imaging system, collimated light is propagated through a lens, filtered with an aperture and then imaged onto a CCD by a second lens. Second system is more compact to improve image quality and to reduce noise. This is achieved by using an off-axis converging laser beam illumination that forms the Fourier plane near the imaging lens. This approach has important advantages such as reducing number of optical components and minimizing the optical path. The system was optimized considering parameters such as laser converging angle, laser beam size at MEMS chip, and magnification of the imaging system