7,592 research outputs found
Energy and precious fuels requirements of fuel alcohol production. Volume 4: Appendices G and H, methanol from coal
Coal mine location, mining technology, energy consumption in mining, coal transport, and potential availability of coal are discussed. Methanol from coal is also discussed
Geoneutrinos in Borexino
This paper describes the Borexino detector and the high-radiopurity studies
and tests that are integral part of the Borexino technology and development.
The application of Borexino to the detection and studies of geoneutrinos is
discussed.Comment: Conference: Neutrino Geophysics Honolulu, Hawaii December 14-16, 200
The Effects of Dissolved Methane upon Liquid Argon Scintillation Light
In this paper we report on measurements of the effects of dissolved methane
upon argon scintillation light. We monitor the light yield from an alpha source
held 20 cm from a cryogenic photomultiplier tube (PMT) assembly as methane is
injected into a high-purity liquid argon volume. We observe significant
suppression of the scintillation light yield by dissolved methane at the 10
part per billion (ppb) level. By examining the late scintillation light time
constant, we determine that this loss is caused by an absorption process and
also see some evidence of methane-induced scintillation quenching at higher
concentrations (50-100 ppb). Using a second PMT assembly we look for visible
re-emission features from the dissolved methane which have been reported in
gas-phase argon methane mixtures, and we find no evidence of visible
re-emission from liquid-phase argon methane mixtures at concentrations between
10 ppb and 0.1%.Comment: 18 pages, 11 figures Updated to match published versio
Technological advancements and their importance for nematode identification
Nematodes represent a species-rich and morphologically diverse group of metazoans known to inhabit both aquatic and terrestrial environments. Their role as biological indicators and as key players in nutrient cycling has been well documented. Some plant-parasitic species are also known to cause significant losses to crop production. In spite of this, there still exists a huge gap in our knowledge of their diversity due to the enormity of time and expertise often involved in characterising species using phenotypic features. Molecular methodology provides useful means of complementing the limited number of reliable diagnostic characters available for morphology-based identification. We discuss herein some of the limitations of traditional taxonomy and how molecular methodologies, especially the use of high-throughput sequencing, have assisted in carrying out large-scale nematode community studies and characterisation of phytonematodes through rapid identification of multiple taxa. We also provide brief descriptions of some the current and almost-outdated high-throughput sequencing platforms and their applications in both plant nematology and soil ecology
Phase and Intensity Distributions of Individual Pulses of PSR B0950+08
The distribution of the intensities of individual pulses of PSR B0950+08 as a
function of the longitudes at which they appear is analyzed. The flux density
of the pulsar at 111 MHz varies strongly from day to day (by up to a factor of
13) due to the passage of the radiation through the interstellar plasma
(interstellar scintillation). The intensities of individual pulses can exceed
the amplitude of the mean pulse profile, obtained by accumulating 770 pulses,
by more than an order of magnitude. The intensity distribution along the mean
profile is very different for weak and strong pulses. The differential
distribution function for the intensities is a power law with index n = -1.1 +-
0.06 up to peak flux densities for individual pulses of the order of 160 Jy
Studies of multiplicity in relativistic heavy-ion collisions
In this talk I'll review the present status of charged particle multiplicity
measurements from heavy-ion collisions. The characteristic features of
multiplicity distributions obtained in Au+Au collisions will be discussed in
terms of collision centrality and energy and compared to those of p+p
collisions. Multiplicity measurements of d+Au collisions at 200 GeV
nucleon-nucleon center-of-mass energy will also be discussed. The results will
be compared to various theoretical models and simple scaling properties of the
data will be identified.Comment: "Focus on Multiplicity" Internationsl Workshop on Particle
Multiplicity in Relativistic Heavy Ion Collisions, Bari, Italy, June 17-19,
2003, 16 pages, 15 figure
Pseudorapidity dependence of parton energy loss in relativistic heavy ion collisions
We analyze the recent data from the BRAHMS Collaboration on the
pseudorapidity dependence of nuclear modification factors in Au+Au collisions
at = 200 GeV by using the full three dimensional hydrodynamic
simulations for the density effects on parton energy loss. We first compute the
transverse spectra at and 2.2, and next take a ratio
, where is a nuclear
modification factor. It is shown that hydrodynamic components account for
at low and that quenched pQCD components lead
at high which are consistent with the data.
Strong suppression at is compatible with the parton energy loss in
the final state.Comment: 5 pages, 4 figures; one figure adde
The physics of the B Factories
“The Physics of the B Factories” describes a decade long effort of physicists in the quest for the precise determination of asymmetry — broken symmetry — between particles and anti-particles. We now recognize that the matter we see around us is the residue — one part in a billion — of the matter and antimatter that existed in the early universe, most of which annihilated into the cosmic background radiation that bathes us. But the question remains: how did the baryonic matter-antimatter asymmetry arise? This book describes the work done by some 1000 physicists and engineers from around the globe on two experimental facilities built to test our understanding of this phenomenon, one at the SLAC National Accelerator Laboratory in California, USA, and a second at the KEK Laboratory, Tsukuba, Japan, and what we have learned from them in broadening our understanding of nature.
Why is our universe dominated by the matter of which we are made rather than equal parts of matter and antimatter? This question has puzzled physicists for decades. However, this was not the question we addressed when we wrote the paper on CP violation in 1972. Our question was whether we can explain the CP violation observed in the K meson decay within the framework of the renormalizable gauge theory. At that time, Sakharov’s seminal paper was already published, but it did not attract our attention. If we were aware of the paper, we would have been misled into seeking a model satisfying Sakharov’s conditions and our paper might not have appeared.
In our paper, we discussed that we need new particles in order to accommodate CP violation into the renormalizable electroweak theory, and proposed the six-quark scheme as one of the possible ways introducing new particles. We thought that the six-quark scheme is very interesting, but it was just a possibility. The situation changed when the tau-lepton was found and it was followed by the discovery of the Upsilon particle. The existence of the third generation became reality. However, it was still uncertain whether the mixing of the six quarks is a real origin of the observed CP violation. Theoretical calculation of CP asymmetries in the neutral K meson system contains uncertainty from strong interaction effects. What settled this problem were the B Factories built at SLAC and KEK.
These B Factories are extraordinary in many ways. In order to fulfill the requirements of special experiments, the beam energies of the colliding electron and positron are asymmetric, and the luminosity is unprecedentedly high. It is also remarkable that severe competition between the two laboratories boosted their performance. One of us (M. Kobayashi) has been watching the development at KEK very closely as the director of the Institute of Particle and Nuclear Studies of KEK for a period of time. As witnesses, we appreciate the amazing achievement of those who participated in these projects at both laboratories.
The B Factories have contributed a great deal to our understanding of particle physics, as documented in this book. In particular, thanks to the high luminosity far exceeding the design value, experimental groups measured mixing angles precisely and verified that the dominant source of CP violation observed in the laboratory experiments is flavor mixing among the three generations of quarks. Obviously we owe our Nobel Prize to this result.
Now we are awaiting the operation of the next generation Super B Factories. In spite of its great success, the Standard Model is not an ultimate theory. For example, it is not thought to be possible for the matter dominance of the universe to be explained by the Standard Model. This means that there will still be unknown particles and unknown interactions. We have a lot of theoretical speculations but experimental means are rather limited. There are great expectations for the Super B Factories to reveal a clue to the world beyond the Standard
Model
Acupuncture in Oncology: The Effectiveness of Acupuncture May Not Depend on Needle Retention Duration
© 2017, © The Author(s) 2017. Background. Guidelines surrounding optimum needle retention duration in acupuncture have not been established, despite a growing evidence base for acupuncture over recent decades. This retrospective study explored the effect of varying acupuncture needle retention durations in cancer patients. Method. Patients received either 2 (n = 35), 10 (n = 53), or 20 minutes (n = 54) of acupuncture once a week for 6 weeks. Outcomes of anxiety and depression, stress, fatigue, and quality of life (QOL), with the Hospital Anxiety and Depression Scale, Perceived Stress Scale, Functional Assessment of Cancer Therapy–Fatigue, and European Organization for Research and Treatment of Cancer Quality of Life, were measured at baseline and at 6 weeks following the intervention. Results. The mean age of participants was 58 years (n = 152). The majority were female, diagnosed with breast cancer. Depression, stress, fatigue, and QOL were significantly improved in all 3 groups at 6 weeks postintervention. No significant differences in all outcomes were found between the 3 groups (≤2 vs 10 minutes vs 20 minutes). There were no differences with the satisfaction of the acupuncture services and perceived efficacy of acupuncture among the 3 groups. More than 95% of participants indicated that they would recommend acupuncture to other cancer patients, friends, and their family members. Conclusion. The efficacy of acupuncture may not only depend on needle retention duration, but may also be associated with multiple factors. Considering the limitations of this study design, robust randomized controlled studies are warranted to confirm the findings
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