97 research outputs found
Noncommutative geometry: fuzzy spaces, the Groenewold-Moyal plane
In this talk, we review the basics concepts of fuzzy physics and quantum field theory on the Groenewold-Moyal Plane as examples of noncommutative spaces in physics. We introduce the basic ideas, and discuss some important results in these fields. At the end we outline some recent developments in the field
UV-IR Mixing in Non-Commutative Plane
Poincar\'e-invariant quantum field theories can be formulated on
non-commutative planes if the coproduct on the Poincar\'e group is suitably
deformed \cite{Dimitrijevic:2004rf, Chaichian:2004za}.(See also especially
Oeckl \cite{Oeckl:1999jun},\cite{Oeckl:2000mar} and Grosse et
al.\cite{Grosse:2001mar}) As shown in \cite{Balachandran:2005eb}, this
important result of these authors implies modification of free field
commutation and anti-commutation relations and striking phenomenological
consequences such as violations of Pauli principle
\cite{Balachandran:2005eb,Bal3}. In this paper we prove that with these
modifications, UV-IR mixing disappears to all orders in perturbation theory
from the -Matrix. This result is in agreement with the previous results of
Oeckl \cite{Oeckl:2000mar}.Comment: Minor Changes in text and abstract, important references adde
Effect of rbST on Serum Biochemical Values During Various Physiological and Weather Conditions in Kundhi Buffaloes
This study was performed to investigate the effect of rbST treatment on some biochemical parameters in addition to values of thyroid hormones in Kundhi buffaloes. Sixteen Kundhi buffaloes were divided into two groups. Group-A (N=8) served as control and Group-B (N=8) was treated with 250 mg of rbST fortnightly for 1st lactation. Blood samples were collected weekly during lactation period from day one to 60 as pre-treatment values and then from day 61 to completion of 1st lactation in Kundhi buffaloes as post-treatment values. The findings revealed overall non significant variation in the serum biochemical and thyroid hormone values between control and rbST treated buffaloes, whereas, significant differences were observed during various physiological and weather conditions in both groups. Glucose and uric acid values were observed higher during parturition and winter season in Kundhi buffaloes. Protein level was higher in rbST treated buffaloes during open days
Ultrasonographic Biometrical Studies on Reproductive Organs of rbST Treated Pregnant Kundhi Buffaloes
Biometrical studies were conducted on sixty four gravid uteri with estimated gestation period of 1st, 2nd, 3rd and 4th month of pregnancy in Kundhi buffaloes. Sixteen specimens for each month of gestation were collected from Hyderabad slaughterhouse to evaluate techniques for measurement of reproductive organs. The measurements for fetometry and morphometry of reproductive organs by ultrasound machine and manually (by measuring tape and vernier caliper) were performed and compared. The Ultrasound examinations were performed through diagnostic ultrasound machine equipped with multi-frequency 5-10MHz transrectal linear array transducer. Analysis revealed that the ovary, foetus, foetal fluid and uterus progressively increased significantly (P<0.01) in weight during 4th month of the gestation than 1st, 2nd and 3rd month of gestation period in rbST treated Kundhi buffaloes. Ovaries with CL were significantly (P<0.01) heavier than the ovary in which CL was absent. Corpus leutum was significantly lighter (P<0.01) during 1st month of pregnancy than 2nd, 3rd and 4th month of pregnancy in rbST treated Kundhi buffaloes. Gravid uterus was significantly heavier (P<0.01) during 4th month of pregnancy than 1st, 2nd and 3rd month of pregnancy in rbST treated Kundhi buffaloes. There was no significant difference between the measurements of oviduct, cervix and vagina during 1st to 4th month of pregnancy. The placenta, foetal fluid and foetus progressively increased significantly in size as gestation period progressed. The ultrasonographic fetometric and morphometric threshold of CRL, TD and UD and foetal weight was steadily increased in rbST treated Kundhi buffaloes. There was significant increase (P<0.05) in the CRL, TD, UD and foetus weight/volume at 4th month of pregnancy than 1st , 2nd and 3rd month of pregnancy in rbST treated Kundhi buffaloes. In conclusion, the overall data indicated that the examination for ultrasonographic fetometry and morphometry of reproductive organs of kundhi buffaloes for evaluation of fetal development, estimation of gestational age and formulation of fetal chart through reproductive organs were more suitable as compare to manual biometrical evaluation
Quantum Fields on the Groenewold-Moyal Plane: C, P, T and CPT
We show that despite the inherent non-locality of quantum field theories on
the Groenewold-Moyal (GM) plane, one can find a class of , ,
and invariant theories. In particular, these are theories
without gauge fields or with just gauge fields and no matter fields. We also
show that in the presence of gauge fields, one can have a field theory where
the Hamiltonian is and invariant while the -matrix
violates and .
In non-abelian gauge theories with matter fields such as the electro-weak and
sectors of the standard model of particle physics, , ,
and the product of any pair of them are broken while
remains intact for the case . (Here , : coordinate functions,
constant.) When ,
it contributes to breaking also and . It is known that the
-matrix in a non-abelian theory depends on only through
. The -matrix is frame dependent. It breaks (the identity
component of the) Lorentz group. All the noncommutative effects vanish if the
scattering takes place in the center-of-mass frame, or any frame where
, but not otherwise. and are good symmetries of the theory in this special case.Comment: 18 pages, 1 figure, revised, 2 references adde
Results of the Search for Strange Quark Matter and Q-balls with the SLIM Experiment
The SLIM experiment at the Chacaltaya high altitude laboratory was sensitive
to nuclearites and Q-balls, which could be present in the cosmic radiation as
possible Dark Matter components. It was sensitive also to strangelets, i.e.
small lumps of Strange Quark Matter predicted at such altitudes by various
phenomenological models. The analysis of 427 m^2 of Nuclear Track Detectors
exposed for 4.22 years showed no candidate event. New upper limits on the flux
of downgoing nuclearites and Q-balls at the 90% C.L. were established. The null
result also restricts models for strangelets propagation through the Earth
atmosphere.Comment: 14 pages, 11 EPS figure
Direction-Dependent CMB Power Spectrum and Statistical Anisotropy from Noncommutative Geometry
Modern cosmology has now emerged as a testing ground for theories beyond the
standard model of particle physics. In this paper, we consider quantum
fluctuations of the inflaton scalar field on certain noncommutative spacetimes
and look for noncommutative corrections in the cosmic microwave background
(CMB) radiation. Inhomogeneities in the distribution of large scale structure
and anisotropies in the CMB radiation can carry traces of noncommutativity of
the early universe. We show that its power spectrum becomes direction-dependent
when spacetime is noncommutative. (The effects due to noncommutativity can be
observed experimentally in the distribution of large scale structure of matter
as well.) Furthermore, we have shown that the probability distribution
determining the temperature fluctuations is not Gaussian for our noncommutative
spacetimes.Comment: 26 pages. v3: Minor correction
The management of diabetic ketoacidosis in children
The object of this review is to provide the definitions, frequency, risk factors, pathophysiology, diagnostic considerations, and management recommendations for diabetic ketoacidosis (DKA) in children and adolescents, and to convey current knowledge of the causes of permanent disability or mortality from complications of DKA or its management, particularly the most common complication, cerebral edema (CE). DKA frequency at the time of diagnosis of pediatric diabetes is 10%–70%, varying with the availability of healthcare and the incidence of type 1 diabetes (T1D) in the community. Recurrent DKA rates are also dependent on medical services and socioeconomic circumstances. Management should be in centers with experience and where vital signs, neurologic status, and biochemistry can be monitored with sufficient frequency to prevent complications or, in the case of CE, to intervene rapidly with mannitol or hypertonic saline infusion. Fluid infusion should precede insulin administration (0.1 U/kg/h) by 1–2 hours; an initial bolus of 10–20 mL/kg 0.9% saline is followed by 0.45% saline calculated to supply maintenance and replace 5%–10% dehydration. Potassium (K) must be replaced early and sufficiently. Bicarbonate administration is contraindicated. The prevention of DKA at onset of diabetes requires an informed community and high index of suspicion; prevention of recurrent DKA, which is almost always due to insulin omission, necessitates a committed team effort
Operation and performance of the ATLAS semiconductor tracker
The semiconductor tracker is a silicon microstrip detector forming part of the inner tracking system of the ATLAS experiment at the LHC. The operation and performance of the semiconductor tracker during the first years of LHC running are described. More than 99% of the detector modules were operational during this period, with an average intrinsic hit efficiency of (99.74±0.04)%. The evolution of the noise occupancy is discussed, and measurements of the Lorentz angle, δ-ray production and energy loss presented. The alignment of the detector is found to be stable at the few-micron level over long periods of time. Radiation damage measurements, which include the evolution of detector leakage currents, are found to be consistent with predictions and are used in the verification of radiation background simulations
Search for H→γγ produced in association with top quarks and constraints on the Yukawa coupling between the top quark and the Higgs boson using data taken at 7 TeV and 8 TeV with the ATLAS detector
A search is performed for Higgs bosons produced in association with top quarks using the diphoton decay mode of the Higgs boson. Selection requirements are optimized separately for leptonic and fully hadronic final states from the top quark decays. The dataset used corresponds to an integrated luminosity of 4.5 fb−14.5 fb−1 of proton–proton collisions at a center-of-mass energy of 7 TeV and 20.3 fb−1 at 8 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. No significant excess over the background prediction is observed and upper limits are set on the tt¯H production cross section. The observed exclusion upper limit at 95% confidence level is 6.7 times the predicted Standard Model cross section value. In addition, limits are set on the strength of the Yukawa coupling between the top quark and the Higgs boson, taking into account the dependence of the tt¯H and tH cross sections as well as the H→γγ branching fraction on the Yukawa coupling. Lower and upper limits at 95% confidence level are set at −1.3 and +8.0 times the Yukawa coupling strength in the Standard Model
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