50,606 research outputs found
Joint perception: gaze and beliefs about social context
The way that we look at images is influenced by social context. Previously we demonstrated this phenomenon of joint perception. If lone participants believed that an unseen other person was also looking at the images they saw, it shifted the balance of their gaze between negative and positive images. The direction of this shift depended upon whether participants thought that later they would be compared against the other person or would be collaborating with them. Here we examined whether the joint perception is caused by beliefs about shared experience (looking at the same images) or beliefs about joint action (being engaged in the same task with the images). We place our results in the context of the emerging field of joint action, and discuss their connection to notions of group emotion and situated cognition. Such findings reveal the persuasive and subtle effect of social context upon cognitive and perceptual processes
The influence of atmosphere on the performance of pure-phase WZ and ZB InAs nanowire transistors
We compare the characteristics of phase-pure MOCVD grown ZB and WZ InAs
nanowire transistors in several atmospheres: air, dry pure N and O, and
N bubbled through liquid HO and alcohols to identify whether
phase-related structural/surface differences affect their response. Both WZ and
ZB give poor gate characteristics in dry state. Adsorption of polar species
reduces off-current by 2-3 orders of magnitude, increases on-off ratio and
significantly reduces sub-threshold slope. The key difference is the greater
sensitivity of WZ to low adsorbate level. We attribute this to facet structure
and its influence on the separation between conduction electrons and surface
adsorption sites. We highlight the important role adsorbed species play in
nanowire device characterisation. WZ is commonly thought superior to ZB in InAs
nanowire transistors. We show this is an artefact of the moderate humidity
found in ambient laboratory conditions: WZ and ZB perform equally poorly in the
dry gas limit yet equally well in the wet gas limit. We also highlight the
vital role density-lowering disorder has in improving gate characteristics, be
it stacking faults in mixed-phase WZ or surface adsorbates in pure-phase
nanowires.Comment: Accepted for publication in Nanotechnolog
Three-boson problem at low energy and Implications for dilute Bose-Einstein condensates
It is shown that the effective interaction strength of three bosons at small
collision energies can be extracted from their wave function at zero energy. An
asymptotic expansion of this wave function at large interparticle distances is
derived, from which is defined a quantity named three-body scattering
hypervolume, which is an analog of the two-body scattering length. Given any
finite-range interaction potentials, one can thus predict the effective
three-body force from a numerical solution of the Schr\"{o}dinger equation. In
this way the constant for hard-sphere bosons is computed, leading to the
complete result for the ground state energy per particle of a dilute
Bose-Einstein condensate (BEC) of hard spheres to order , where
is the number density. Effects of are also demonstrated in the three-body
energy in a finite box of size , which is expanded to the order ,
and in the three-body scattering amplitude in vacuum. Another key prediction is
that there is a violation of the effective field theory (EFT) in the condensate
fraction in dilute BECs, caused by short-range physics. EFT predictions for the
ground state energy and few-body scattering amplitudes, however, are
corroborated.Comment: 24 pages, no figur
Photon-number-solving Decoy State Quantum Key Distribution
In this paper, a photon-number-resolving decoy state quantum key distribution
scheme is presented based on recent experimental advancements. A new upper
bound on the fraction of counts caused by multiphoton pulses is given. This
upper bound is independent of intensity of the decoy source, so that both the
signal pulses and the decoy pulses can be used to generate the raw key after
verified the security of the communication. This upper bound is also the lower
bound on the fraction of counts caused by multiphoton pulses as long as faint
coherent sources and high lossy channels are used. We show that Eve's coherent
multiphoton pulse (CMP) attack is more efficient than symmetric individual (SI)
attack when quantum bit error rate is small, so that CMP attack should be
considered to ensure the security of the final key. finally, optimal intensity
of laser source is presented which provides 23.9 km increase in the
transmission distance. 03.67.DdComment: This is a detailed and extended version of quant-ph/0504221. In this
paper, a detailed discussion of photon-number-resolving QKD scheme is
presented. Moreover, the detailed discussion of coherent multiphoton pulse
attack (CMP) is presented. 2 figures and some discussions are added. A
detailed cauculation of the "new" upper bound 'is presente
Effects of rapid thermal annealing on device characteristics of InGaAs/GaAs quantum dot infrared photodetectors
In this work, rapid thermal annealing was performed on InGaAs/GaAs quantum dot infrared photodetectors (QDIPs) at different temperatures. The photoluminescence showed a blueshifted spectrum in comparison with the as-grown sample when the annealing temperature was higher than 700 °C, as a result of thermal interdiffusion of the quantum dots (QDs). Correspondingly, the spectral response from the annealed QDIP exhibited a redshift. At the higher annealing temperature of 800 °C, in addition to the largely redshifted photoresponse peak of 7.4 µm (compared with the 6.1 µm of the as-grown QDIP), a high energy peak at 5.6 µm (220 meV) was also observed, leading to a broad spectrum linewidth of 40%. This is due to the large interdiffusion effect which could greatly vary the composition of the QDs and thus increase the relative optical absorption intensity at higher energy. The other important detector characteristics such as dark current, peak responsivity, and detectivity were also measured. It was found that the overall device performance was not affected by low annealing temperature, however, for high annealing temperature, some degradation in device detectivity (but not responsivity) was observed. This is a consequence of increased dark current due to defect formation and increased ground state energy. © 2006 American Institute of Physic
Adipokinetic effect of corpora cardiaca extract in Valanga nigricornis (Burm.)
1. The effect of injection of corpora cardiaca (CC) extract on haemolymph lipid concentration of V. nigricornis was studied. 2. The CC extract caused a marked increase in the haemolymph lipid, which attained a peak at about 1 1/2 hr after injection. At longer intervals of up to 4 hr, this response was markedly diminished. 3. The results were considered in relation to the natural habit of the insect; it is suggested that the adipokinetic effect probably represents an adaptive mechanism to non-flight physiological conditions like starvation
Mechanistic and pathological study of the genesis, growth, and rupture of abdominal aortic aneurysms
Postprint (published version
Polarisation-sensitive terahertz detection by multicontact photoconductive receivers
We have developed a terahertz radiation detector that measures both the
amplitude and polarization of the electric field as a function of time. The
device is a three-contact photoconductive receiver designed so that two
orthogonal electric-field components of an arbitrary polarized electromagnetic
wave may be detected simultaneously. The detector was fabricated on Fe+
ion-implanted InP. Polarization-sensitive detection is demonstrated with an
extinction ratio better than 100:1. This type of device will have immediate
application in studies of birefringent and optically active materials in the
far-infrared region of the spectrum.Comment: 3 pages, 3 figure
The Nonduality of Motion and Rest: Sengzhao on the Change of Things
In his essay “Things Do Not Move,” Sengzhao (374?−414 CE), a prominent Chinese Buddhist philosopher, argues for the thesis that the myriad things do not move in time. This view is counter-intuitive and seems to run counter to the Mahayana Buddhist doctrine of emptiness. In this book chapter, I assess Sengzhao’s arguments for his thesis, elucidate his stance on the change/nonchange of things, and discuss related problems. I argue that although Sengzhao is keen on showing the plausibility of the thesis, he actually views the myriad things as both changing and unchanging and upholds the nonduality of motion and rest. In fact, the nonmoving thesis follows from the discernment that things change from moment to moment without there being any enduring stuff in the process. Among philosophical works that confer a higher ontological status on nonchange over change, Sengzhao’s essay is unique and well worth pondering
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