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The authors have studied the transport properties of carbon nanotube quantum dots under terahertz (THz) wave irradiation. The experimental data have shown that the satellite currents are generated with the THz irradiation, and that the peak position of the satellite currents varies linearly with the THz photon energy. These results provide experimental evidence for photon-assisted tunneling in the THz region. The present observation provides the interesting possibility of developing a highly sensitive and frequency-tunable THz detector capable of high-temperature operation. [ABSTRACT FROM AUTHOR]

Abstract: We present experimental results on the low-temperature transport of an individual single-wall carbon nanotube (SWNT) quantum dot. A variety of features in the Coulomb diamonds have been observed, such as a distortion of Coulomb diamonds as well as standard diamonds with a rectangular shape, depending on a gate voltage range. Magnetic field studies have revealed the simple Zeeman splitting of single particle states in some gate voltage ranges and a spin polarization in the dot in other gate voltage range. Our results suggest the importance of electron–electron interactions and the single particle states which move differently with a gate voltage. [Copyright &y& Elsevier]

OBJECTIVE: The autoimmune response appears to play an important role in some types of acute sensorineural hearing loss. Endolymphatic hydrops associated with fluctuating hearing loss has also been suggested to be caused by an immunological mechanism. Acute low-tone hearing loss (ALHL) associated with Meniere's disease (MD) is characterized by fluctuating hearing loss, and its etiology is thought to involve endolymphatic hydrops. The aim of this study was to attempt to determine the etiology of ALHL in MD. MATERIAL AND METHODS: A flow cytometer was used to analyze intracellular cytokine levels in peripheral blood from 19 patients with ALHL and 26 patients with MD and the data compared to those obtained from age- and gender-matched healthy volunteers. RESULTS: The patients with ALHL showed significantly increased levels of Th1 subsets (interferon-gamma-producing helper T cells) as compared to those in normal controls. The levels of Th2 (IL-4-producing helper T cells) subsets did not differ from those in the control group and thus Th1 predominated in ALHL patients. The patients with MD showed significantly increased natural killer cell activity but no Th1 dominance. These patients had no obvious systemic or local disease except in the inner ear. CONCLUSION: An abnormality of the Th1/Th2 balance in ALHL and increased natural killer cell activity in MD are thought to relate to inner ear disorder. These results are consistent with the possibility that the etiology of ALHL and MD involves an immune response. [ABSTRACT FROM AUTHOR]

Abstract Rationale: While several environmental situations may produce cocaine craving, there is little research on whether patterns of drug cue reactivity are similar across different environmental situations. Objective: This study examined whether two different environmental situations, psychological stress and drug cues, produce similar or varying patterns of cue reactivity in 20 cocaine dependent individuals. Methods: All subjects participated in a single laboratory session and were exposed to stress, drug cues and neutral-relaxing imagery conditions. Cocaine and alcohol craving, emotion state ratings, subjective anxiety, heart rate and salivary cortisol measures were assessed. Results: Significant increases in cocaine and alcohol craving were observed with stress and drug cues imagery but not with neutral-relaxing imagery. In addition, stress and drug cues situations produced similar increases in subjective anxiety, heart rate and salivary cortisol levels. Significant increases in negative emotion ratings and decreases in positive emotion ratings were found for stress and drug cues conditions as compared to the neutral condition. Conclusions: The findings indicate that a similar and comparable pattern of cue reactivity is induced by stress and drug cue manipulations. Furthermore, the comparable increases in subjective anxiety and negative affect observed with stress-induced and drug cue-induced craving provides support for the negative reinforcement model of drug craving and relapse. The negative affectivity co-occurring with the craving state appears to be an important target in the development of new treatments for cocaine dependence. [ABSTRACT FROM AUTHOR]

The authors have studied the effect of terahertz irradiation on single-electron transistors (SETs) based on single-wall carbon nanotubes, and have observed that the radiation generates Coulomb peak shifts. Time-resolved measurements of the terahertz response have revealed that the peak-shift signal has very long time constants, measured in seconds, and that the time trace of the signal after the terahertz irradiation is turned off deviates from a single-exponential curve. These experimental results suggest that the terahertz irradiation causes a charging process in trap states in the close vicinity of the SET, leading to a change in its effective gate voltage. [ABSTRACT FROM AUTHOR]

Single-quantum dots have been fabricated in an individual single-wall carbon nanotube, and the single-electron-transport measurements have been carried out at 40 mK. Coulomb diamonds showed an alternate change of the diamond size, an even-odd effect, indicating the two-electron shell filling. An excitation spectroscopy in which a Coulomb oscillation peak was measured in magnetic fields with a large source-drain bias voltage revealed the Zeeman splitting of single-particle states. The results suggest an important step for preparation of the spin two-level system. [ABSTRACT FROM AUTHOR]

Abstract: We demonstrate selecting a Coulomb peak which originates from a single quantum dot, from a bundle of many single-wall carbon nanotubes. The method uses the previously reported current flowing process, by which the number of nanotubes can be reduced for the transport. By adjusting the gate voltage in an appropriate range, the single peak belonging to the single quantum dot has been selected. The effect of the high frequency application on the peak has been investigated, and it is shown that the basic response can be explained by the adiabatic response of the single dot to the high frequency signal. [Copyright &y& Elsevier]

A large current flowing process has been used at 1.5 K to modify transport properties of quantum dots in a bundle of single-walled carbon nanotubes. After the processes were applied to the samples a few times, Coulomb oscillations started to be observed that did not appear before the process. The number of Coulomb peaks decreased as the process was repeated. The experimental observations could be explained by the simple model that the nanotube bundle was composed of many single and multiquantum dots in parallel, and some of them were broken by the current flowing process. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We derive the Hamiltonian of a superconducting circuit that comprises a single-Josephson-junction flux qubit inductively coupled to an LC oscillator, and we compare the derived circuit Hamiltonian with the quantum Rabi Hamiltonian, which describes a two-level system coupled to a harmonic oscillator. We show that there is a simple, intuitive correspondence between the circuit Hamiltonian and the quantum Rabi Hamiltonian. While there is an overall shift of the entire spectrum, the energy level structure of the circuit Hamiltonian up to the seventh excited states can still be fitted well by the quantum Rabi Hamiltonian even in the case where the coupling strength is larger than the frequencies of the qubit and the oscillator, i.e., when the qubit-oscillator circuit is in the deep–strong-coupling regime. We also show that although the circuit Hamiltonian can be transformed via a unitary transformation to a Hamiltonian containing a capacitive coupling term, the resulting circuit Hamiltonian cannot be approximated by the variant of the quantum Rabi Hamiltonian that is obtained using an analogous procedure for mapping the circuit variables onto Pauli and harmonic oscillator operators, even for relatively weak coupling. This difference between the flux and charge gauges follows from the properties of the qubit Hamiltonian eigenstates. [ABSTRACT FROM AUTHOR]

We report on experimentally measured light shifts of superconducting flux qubits deep-strongly coupled to LC oscillators, where the coupling constants are comparable to the qubit and oscillator resonance frequencies. By using two-tone spectroscopy, the energies of the six lowest levels of each circuit are determined. We find huge Lamb shifts that exceed 90% of the bare qubit frequencies and inversions of the qubits' ground and excited states when there are a finite number of photons in the oscillator. Our experimental results agree with theoretical predictions based on the quantum Rabi model. [ABSTRACT FROM AUTHOR]

Abstract: We investigate the Hubbard–Holstein model by using the dynamical mean-field theory combined with the exact diagonalization method. Below a critical temperature , a coexistence of two solutions, small lattice fluctuating solution (polaronic state) and large one (bipolaronic state), is found for the same value of the electron–phonon coupling g in the range for a fixed value of the Coulomb interaction U. As the result, the system shows a first-order phase transition at (

The time-course of the recovery of the hearing level after treatment in 90 patients with idiopathic sudden sensorineural hearing loss was examined. The improvement rate calculated relative to the hearing level of the opposite ear was investigated to estimate the hearing recovery. Follow-up audiograms were performed once per week for 1 month after treatment and once per month thereafter. There were two groups that differed with respect to the characteristics of hearing recovery. One group showed an improvement rate of over 50% at 1–2 weeks and a good improvement rate at 3 months after treatment. In the other group, the improvement rate did not reach 50% at 1–2 weeks, and the improvement rate was poor at 3 months after treatment. The patients with improvement rates of over 50% at 1–2 weeks had earlier initial visits and had mild hearing loss, whereas the patients with profound hearing loss had improvement rates under 50% and poor long-term prognosis. We conclude that the improvement rate at 1–2 weeks after treatment predicts the long-term prognosis for recovery of hearing level in patients with sudden sensorineural hearing loss. [ABSTRACT FROM AUTHOR]

Abstract: Quantum dots have been fabricated with single-wall carbon nanotubes (SWCNTs), and their transport properties have been measured at low temperatures. The single-electron transport measurements revealed the artificial atom characteristics with a shell structure and the Zeeman splitting of single particle states. They have been observed with the metallic SWCNT that includes many electrons, in striking contrast to the case of semiconductor artificial atoms that have a few electrons. The unique features in the SWCNT artificial atom are discussed in terms of the energy scales associated with the quantum dot. [Copyright &y& Elsevier]

Abstract: A high dispersion spectroscopic observation of Comet 116P/Wild 4 was performed on June 10, 2003, using the High Dispersion Spectrograph (HDS) on Subaru Telescope, when the comet was at 2.4AU from the Sun. Three forbidden oxygen emission lines in optical region, the green line at 557.7330nm (from 1S to 1D meta-stable state) and the red doublet lines at 630.0304 and 636.3776nm (from 1D meta-stable state to 3P state) were observed. The oxygen atoms in meta-stable state are considered to be generated by the photo-dissociation of parent molecules such as H2O, CO, CO2, etc. H2O molecule is usually thought as the most dominant source of these oxygens in meta-stable state when a comet is at around 1AU from the Sun. However, since the Comet 116P/Wild 4 was located at 2.4AU far from the Sun at the observation, CO and/or CO2 could be a possible main source(s) of meta-stable oxygen atoms rather than H2O. The ratio between red doublet lines (630.0304nm relative to 636.3776nm) derived from our result is 2.94±0.07, and the ratio of green line to the red doublet lines is 0.155±0.007. The ratio of green to red doublet lines, which indicates the ratio of O(1S) to O(1D), give us a clue to distinguish the source of meta-stable oxygen atoms from different parent molecules. Considering the abundance of CO is comparable to or smaller than CO2, CO2 could be thought as the parent molecules of the meta-stable oxygen atoms as well as H2O. The number ratio of CO2/H2O within our observational aperture is discussed in this paper. [Copyright &y& Elsevier]

We investigated in detail the structural ordering developed in films of tetrahedral amorphous carbon (ta-C) under 100 kV to 200 kV electron beams of transmission electron microscopes (TEM). From systematic measurements of electron diffraction and electron energy loss spectra (EELS), in selected areas the ordered structures were concluded to be multi-walled carbon nanotubes or warped graphitic platelets containing a high density of defects. The electron-irradiation-induced ordering can neither be accounted for by a sample heating nor be explained only by displacement damage caused by 200 kV electron irradiation. The essential process, that is enhanced, appears the atomic diffusion induced by electronic excitations due to the electron irradiation. [ABSTRACT FROM PUBLISHER]

We investigated in detail the structural ordering developed in films of tetrahedral amorphous carbon (ta-C) under 100 kV to 200 kV electron beams of transmission electron microscopes (TEM). From systematic measurements of electron diffraction and electron energy loss spectra (EELS), in selected areas the ordered structures were concluded to be multi-walled carbon nanotubes or warped graphitic platelets containing a high density of defects. The electron-irradiation-induced ordering can neither be accounted for by a sample heating nor be explained only by displacement damage caused by 200 kV electron irradiation. The essential process, that is enhanced, appears the atomic diffusion induced by electronic excitations due to the electron irradiation. [ABSTRACT FROM AUTHOR]

The quantum efficiency of NbN and NbTiN superconducting single photon detectors drops with decreasing photon energy. A lower gap material would enable single photon detection deeper in the infrared. We have fabricated a NbSi detector and compare its characteristics with a NbTiN device. NbSi (TC≃2 K) has a smaller superconducting gap than NbTiN or NbN (TC≃15 K). We measure the detection efficiency for a wavelength range from 1100 to 1900 nm. In this range the NbSi detector shows a 10-fold increase in relative efficiency with respect to the NbTiN detector. [ABSTRACT FROM AUTHOR]

Abstract: Large-sized bubble detectors with microscopic droplets of superheated liquids of dichlorodifluoromethane (Freon-12), dichlorotetrafluoroethane (Freon-114), tetrafluoroethane (Freon-134a), and mixture of Freon-12 and Freon-114, respectively, were irradiated with 150MeV/amu helium ions at the HIMAC accelerator in NIRS, Chiba, Japan. Distributions of bubbles produced by the helium ions have been studied in each type of the detectors. The origin of the bubbles has been investigated. The detection efficiency of each type of the bubble detectors for helium ions with respect to the energy of the ions has been obtained. The phenomenon of bubble occurrence and its possible applications to the determination of He intensity from accelerators, research of track formation mechanism, energy loss straggling and neutron detection in the space and at higher altitude are discussed. [Copyright &y& Elsevier]

Abstract: Comet 85P/Boethin was selected as the original comet target for the Deep Impact extended mission, EPOXI. Because this comet had been only observed at two apparitions in 1975 and 1986 and consequently had a large ephemeris error, an early intense recovery effort similar to that of 1P/Halley was undertaken beginning in 2005 using the ESO Very Large Telescopes (VLTs) in a distant comet program. These were challenging observations because of the low galactic latitude, and an error ellipse (the line of variations) that was larger than the CCD FOV, and the comet was not seen. Dedicated recovery observing time was awarded on the Subaru telescope in April and May 2006, and June 2007, in addition to time on the VLT and Canada–France–Hawaii telescopes during July–August 2007 with wide field mosaics and mosaicing techniques. The limiting V magnitudes from these observing runs ranged between 25.7 and 27.3 and again the comet was not seen in the individual nights. A new image processing technique was developed to stack images over extended runs and runs after distorting them to account for dilations and rotations in the line of variations using modifications of the world coordinate system. A candidate at V ∼27.3 was found in the CFHT data along the LOV, 2.5′ west of the nominal ephemeris position. The EPOXI mission was unwilling to re-target the spacecraft without a confirmation. Additional time was secured using the Spitzer Space Telescope, the Gemini South 8-m telescope, the Clay and Baade (Magellan 6.5m), CTIO 4m, and SOAR 4m telescopes during 2007 September and October A composite image made by stacking the new data showed no plausible candidate nucleus to a limiting magnitude of V =28.5, corresponding to a nucleus radius between 0.1 and 0.2km (assuming an albedo of 0.04). The comet was declared lost, presumably having disintegrated. Searches in the WISE data set revealed no debris trail, but no constraints on the possible time of disruption can be made. NASA approved the trajectory correction maneuver to go to Comet 103P/Hartley 2 on 2007 November 1. Many observers searched for the comet as it came to its December 2008 perihelion, but no trace of the nucleus was found. Based on observations collected at the Very Large Telescope, Chile, in part on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan, in part using data gathered with the 6.5m Magellan Telescopes located at Las Campanas Observatory, Chile, in part on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada–France–Hawaii Telescope (CFHT) which is operated by the National Research Council (NRC) of Canada, the Institut National des Science de l’Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii, in part using data collected at the Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatory, which are operated by the Association for Research in Astronomy, under contract with the National Science Foundation, and in part on observations obtained at the Southern Astrophysical Research (SOAR) telescope, which is a joint project of the Ministério da Ciência, Tecnologia, e Inovação (MCTI) da República Federativa do Brasil, the U.S. National Optical Astronomy Observatory (NOAO), the University of North Carolina at Chapel Hill (UNC), and Michigan State University (MSU). This work is also based in part on observations taken with the Spitzer Space Telescope, which is operated by JPL/Caltech under a contract with NASA. [Copyright &y& Elsevier]

Abstract: Thermal-IR imaging from space-borne and ground-based observatories was used to investigate the temperature, composition and aerosol structure of Jupiter’s Great Red Spot (GRS) and its temporal variability between 1995 and 2008. An elliptical warm core, extending over 8° of longitude and 3° of latitude, was observed within the cold anticyclonic vortex at 21°S. The warm airmass is co-located with the deepest red coloration of the GRS interior. The maximum contrast between the core and the coldest regions of the GRS was 3.0–3.5K in the north–south direction at 400mbar atmospheric pressure, although the warmer temperatures are present throughout the 150–500mbar range. The resulting thermal gradients cause counter-rotating flow in the GRS center to decay with altitude into the lower stratosphere. The elliptical warm airmass was too small to be observed in IRTF imaging prior to 2006, but was present throughout the 2006–2008 period in VLT, Subaru and Gemini imaging. Spatially-resolved maps of mid-IR tropospheric aerosol opacity revealed a well-defined lane of depleted aerosols around the GRS periphery, and a correlation with visibly-dark jovian clouds and bright 4.8-μm emission. Ammonia showed a similar but broader ring of depletion encircling the GRS. This narrow lane of subsidence keeps red aerosols physically separate from white aerosols external to the GRS. The visibility of the 4.8-μm bright periphery varies with the mid-IR aerosol opacity of the upper troposphere. Compositional maps of ammonia, phosphine and para-H2 within the GRS interior all exhibit north–south asymmetries, with evidence for higher concentrations north of the warm central core and the strongest depletions in a symmetric arc near the southern periphery. Small-scale enhancements in temperature, NH3 and aerosol opacity associated with localized convection are observed within the generally-warm and aerosol-free South Equatorial Belt (SEB) northwest of the GRS. The extent of 4.8-μm emission from the SEB varied as a part of the 2007 ‘global upheaval,’ though changes during this period were restricted to pressures greater than 500mbar. Finally, a region of enhanced temperatures extended southwest of the GRS during the survey, restricted to the 100–400mbar range and with no counterpart in visible imaging or compositional mapping. The warm airmass was perturbed by frequent encounters with the cold airmass of Oval BA, but no internal thermal or compositional effects were noted in either vortex during the close encounters. [Copyright &y& Elsevier]

Abstract: Large sized bubble detectors with different sensitivities have been irradiated with high-energy protons at the cyclotron in RIKEN, Japan. Distributions of bubbles induced by the protons in the detectors have been studied. It shows that quite a large number of random bubbles are produced in the detectors in the range traveled by the beam protons. The existence of random bubbles hints that high-energy protons as an important component of primary and secondary cosmic rays at higher altitude and in space may cause significant number of bubbles in the bubble detectors in aircrafts or spacecrafts. The origin of the random bubbles has been investigated. The detection efficiencies of bubble detectors for protons via the random bubbles have been determined, being (0.93±0.27)×10−2, (4.6±1.5)×10−2 and (4.7±1.7)×10−2 (Bubble cm−3)/(Proton cm−2), respectively for T-14, T-24 and T-12 types of bubble detectors. The detection efficiencies for protons are quite high, which are about two orders of magnitude higher than that for 0.3–19MeV mono-energetic neutrons. The astonishing high efficiencies for protons can only be attributed to Rutherford scattering of protons with nuclei of C, F, and Cl in the compositions of superheated liquid droplets in the detectors. The recoil nuclei of C, F and Cl from Rutherford scattering create the random bubbles. In contrast, in terrestrial calibrations of bubble detectors with mono-energetic neutrons, only nuclear interactions of neutrons with nuclei are involved. Special consideration must be given to the effect of Rutherford scattering of high-energy protons on detection of neutrons with bubble detectors at higher altitude and in space. [Copyright &y& Elsevier]

Summary The CONSTANS (CO ) gene of Arabidopsis plays a key role in the photoperiodic flowering pathway. To investigate photoperiod responses in cereals in more detail, we isolated three kinds of CO/Hd1 (rice ortholog of CO ) homolog from hexaploid wheat, derived from the A, B, and D genomes and designated as wheat ortholog of CO from A genome (TaHd1-1), TaHd1-2 , and TaHd1-3 , respectively. They were highly similar to each other and to Hd1 , and in addition harbored two conserved regions: two zinc finger motifs and CONSTANS, CONSTANS-LIKE and TIMING OF CAB EXPRESSION 1 (CCT) domain like CO/Hd1 . They were located on the long arm of the homoeologous chromosome 6. TaHd1-2 harbored a 63-bp deletion at the promoter region containing the GATA-1 box, and consequently, we detected no subsequent transcript. The TaHd1-1 genomic clone was introduced to a rice line deficient in Hd1 function. Transgenic plants complemented the functions of rice Hd1: they promoted heading under short-day (SD) conditions and delayed it under long-day (LD)/natural conditions, indicating that Hd1 proteins from SD and LD plants share common structures and functions. [ABSTRACT FROM AUTHOR]

Rendezvous of the Japanese spacecraft Hayabusa with the near-Earth asteroid 25143 Itokawa took place during the interval September through November 2005. The onboard camera imaged the solid surface of this tiny asteroid (535 meters by 294 meters by 209 meters) with a spatial resolution of 70 centimeters per pixel, revealing diverse surface morphologies. Unlike previously explored asteroids, the surface of Itokawa reveals both rough and smooth terrains. Craters generally show unclear morphologies. Numerous boulders on Itokawa's surface suggest a rubble-pile structure. [ABSTRACT FROM AUTHOR]

Abstract: Calculations on the formation of a linear track of a heavy ion in bubble detector have been carried out based on a theoretical model considering the minimum energy (including bubble surface energy, internal energy, evaporation energy, expansion energy, kinetic energy and viscous energy) required during the formation of a critical bubble at the cost of the ionization energy of the heavy ion. The calculated minimum energy is 8.99keV for dichlorodifluoromethane (R-12) at 25°C. The results of calculations have been combined with those of calibrations of bubble detectors with heavy ions at accelerator. The threshold (1.510.04) MeVmg cm is obtained in the calibration with heavy ions for the above liquid and temperature. It shows that the distance over which the heavy ion traverses and transfers energy to the superheated liquid to produce a critical bubble is 4.67 times the radius of the seed bubble. The radius of the cylinder along which the heavy ion deposits energy to form a seed bubble is about 5.2nm. This dimension indicates that the process of track formation in bubble detectors is consistent with the model of thermal spike. [Copyright &y& Elsevier]

The impact cratering process on a comet is controversial but holds the key for interpreting observations of the Deep Impact collision with comet 9P/Tempel 1. Mid-infrared data from the Cooled Mid-Infrared Camera and Spectrometer (COMICS) of the Subaru Telescope indicate that the large-scale dust plume ejected by the impact contained a large mass (∼10[sup 6] kilograms) of dust and formed two wings approximately ±45° from the symmetric center, both consistent with gravity as the primary control on the impact and its immediate aftermath. The dust distribution in the inner part of the plume, however, is inconsistent with a pure gravity control and implies that evaporation and expansion of volatiles accelerated dust. [ABSTRACT FROM AUTHOR]

Carbon nanotubes are attractive materials as a building block of quantum dot devices because of their small diameter. However, to fabricate integrated quantum dot devices, device fabrication processes suitable for nanotubes have to be developed. In this paper, we present our approach to fabricate a single quantum dot, coupled quantum dots and single electron inverter with two single electron transistors integrated in series, as a first step to realize more complicated quantum dot devices. [Copyright &y& Elsevier]

Five types of bubble detectors (T-15, T-34, T-12, T-24 and T-14) of large volume and different sensitivities were developed in the China Institute of Atomic Energy for the purpose of heavy ion research. Calibrations were carried out with beams of high-energy protons, He, C, Si, Ar, Fe, Kr and Xe, at accelerators in the energy region 150–650 MeV/u. The bubble detectors were demonstrated to be a family of detectors for recording tracks of high-energy heavy ions with atomic numbers from Z=1 (proton) to all the numbers in the whole periodic table of elements. The threshold levels of the detectors differ from each other with values 0.05±0.01 (T-15), 1.62±0.05 (T-34), 1.68±0.03 (T-12), 2.24±0.06 (T-24) and 6.04±0.80 (T-14) MeV mg−1 cm2, respectively, which are about the same or even lower than the levels of plastic track detectors for recording heavy ions. The distinguishing features of bubble detectors are high sensitivity, active recording, real-time display, volume registration and background discriminating capacities. Bubble detectors are a new type of high sensitivity detectors and are very promising for detection of heavy ions, neutrons and exotic particles. [Copyright &y& Elsevier]

Bubble detectors were irradiated with protons and demonstrated that a special type of bubble detector could directly record proton tracks. The track of a proton is composed of one or more bubbles at the Bragg peak in the end of the proton range. A proton can produce at least one bubble as its track. Successful recording of proton tracks shows that bubble detectors can be used as a new type of heavy ion track detector to register all nuclei with atomic numbers in the entire Periodic Table of Elements. The applications of bubble detectors based on proton registration have been desired in the study of nuclear interactions, space research and cancer therapy. [Copyright &y& Elsevier]