Subwavelength atom localization via amplitude and phase control of the absorption spectrum

We propose a scheme for subwavelength localization of an atom conditioned upon the absorption of a weak probe field at a particular frequency. Manipulating atom-field interaction on a certain transition by applying drive fields on nearby coupled transitions leads to interesting effects in the absorption spectrum of the weak probe field. We exploit this fact and employ a four-level system with three driving fields and a weak probe field, where one of the drive fields is a standing-wave field of a cavity. We show that the position of an atom along this standing wave is determined when probe field absorption is measured. We find that absorption of the weak probe field at a certain frequency leads to subwavelength localization of the atom in either of the two half-wavelength regions of the cavity field by appropriate choice of the system parameters. We term this result as sub-half-wavelength localization to contrast it with the usual atom localization result of four peaks spread over one wavelength of the standing wave. We observe two localization peaks in either of the two half-wavelength regions along the cavity axis.Comment: Accepted for publication to Physical Review

What information can we obtain from the yield ratio π−/π+\pi^-/\pi^+ in heavy-ion collisions ?

The recently reported data on the yield ratio $\pi^-/\pi^+$ in central rapidity region of heavy-ion collisions are analyzed by theoretical formula which accounts for Coulomb interaction between central charged fragment (CCF) consisting of nearly stopped nucleons with effective charge Z_{\mbox{\scriptsize eff}} and charged pions produced in the same region of the phase space. The Coulomb wave function method is used instead of the usual Gamow factor in order to account for the finite production range of pions, $\beta$. For Gaussian shape of the pion production sources it results in a quasi-scaling in $\beta$ and Z_{\mbox{\scriptsize eff}} which makes determination of parameters $\beta$ and Z_{\mbox{\scriptsize eff}} from the existing experimental data difficult. Only sufficiently accurate data taken in the extreme small $m_{\scriptscriptstyle T}$-$m_{\pi}$ region, where this quasi-scaling is broken, could be used for this purpose.Comment: 7 pages, Latex type, 8 figure

Paracetamol versus meperidine for relief of labour pain in primiparous women: a randomized controlled trial

Background: Most parturient women request analgesia, of which, there are two types; opioids and non-opioids. Opioids include morphine and meperidine, while non-opioids, which are milder forms of painkillers, include acetaminophen (paracetamol) and non-steroid anti-inflammatory drugs. The major concerns associated with opioids are the risk of neonatal respiratory depression, the cost and availability.Methods: The aim of this study was to compare the efficacy and safety of paracetamol versus meperidine for intra-partum pain relief. A total of 92 primiparous singleton term pregnant women were randomly allocated to receive intravenous paracetamol (1000 mg), or intramuscular meperidine (50 mg), at the beginning of the active phase of labor. The primary outcome was the labor pain perception, assessed using the visual analogue scale (VAS), at baseline, 15, 30, 60 and 120 minutes after administration of the drug.Results: Women of both groups showed significant reduction of the VAS after administration of the medication. There were no differences between both groups regarding the mode of delivery and the durations of the first or second stages of labor. However, meperidine was associated with higher rates of dizziness and nausea/vomiting. The 1-min Apgar scores were significantly lower in meperidine group. However, there were no differences in the 5-min Apgar score, need for neonatal resuscitation or neonatal respiratory distress.Conclusions: intravenous paracetamol as analgesia during labor is effective with no fetal or maternal adverse effects. Its use should have more chance for intrapartum pain relief. Additionally, it can be used as adjuvant with other types of analgesics

Development of a web based financial application system

Th e paper describes a technique to develop a web based financial system, following latest technology and business needs. In the develo pment of web based application, the user friendliness and technology both are very important . It is used ASP .NET MVC 4 platform and SQL 2008 server for development of web based financ ial system. It shows the technique for the entry system and report monitoring of the appli cation is user friendly. This paper also highlights the critical situations of development, w hich will help to develop the quality product

Group velocity control in the ultraviolet domain via interacting dark-state resonances

The propagation of a weak probe field in a laser-driven four-level atomic system is investigated. We choose mercury as our model system, where the probe transition is in the ultraviolet region. A high-resolution peak appears in the optical spectra due to the presence of interacting dark resonances. We show that this narrow peak leads to superluminal light propagation with strong absorption, and thus by itself is only of limited interest. But if in addition a weak incoherent pump field is applied to the probe transition, then the peak structure can be changed such that both sub- and superluminal light propagation or a negative group velocity can be achieved without absorption, controlled by the incoherent pumping strength

Quasiscaling in the analysis of the yield ratio π−/π+\pi^-/\pi^+: Mathematical structure and estimation of source size

Recently we have found that integral of the squared Coulomb wave function describing systemcomposed of charged pion and central charged fragment $Z_{eff}$ protons, $|\psi_r(r)|^2$, times pion source function $\rho(r)$ (of the size $\beta$), \intdr |\psi_r(r)|^2 \rho(r), shows a quasiscaling behavior. This is approximately invariant under the following transformation: $(\beta,Z_{eff}) \to (\lambda\beta,\lambda Z_{eff})$; $\lambda >0$. We called such behavior $\beta-Z_{eff}$ quasiscaling. We examine this quasiscaling behavior in detail. In particular we provide a semi-analytical examination of this behavior and confirm it for the exponential pionic source functions in addition to the Gaussian ones and for the production of K mesons as well. When combined with the results of the HBT, a result of the yield ratio allows us to estimate the size of the central charged fragment (CCF) to be $125\le Z_{eff}\le 150$ for Pb+Pb collisions at energy 158 GeV/nucleon. From our estimation, the baryon number density $0.024 \le n_{B}\le0.036$ [1/fm^3] is obtained.Comment: 7 pages, RevTex, 6figure

Mitochondrial DNA (mtDNA) haplotypes and dysfunctions in presbyacusis.

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Coulomb Effect: A Possible Probe for the Evolution of Hadronic Matter

Electromagnetic field produced in high-energy heavy-ion collisions contains much useful information, because the field can be directly related to the motion of the matter in the whole stage of the reaction. One can divide the total electromagnetic field into three parts, i.e., the contributions from the incident nuclei, non-participating nucleons and charged fluid, the latter consisting of strongly interacting hadrons or quarks. Parametrizing the space-time evolution of the charged fluid based on hydrodynamic model, we study the development of the electromagnetic field which accompanies the high-energy heavy-ion collisions. We found that the incident nuclei bring a rather strong electromagnetic field to the interaction region of hadrons or quarks over a few fm after the collision. On the other hand, the observed charged hadrons' spectra are mostly affected (Coulomb effect) by the field of the charged fluid. We compare the result of our model with experimental data and found that the model reproduces them well. The pion yield ratio pi^-/pi+ at a RHIC energy, Au+Au 100+100 GeV/nucleon, is also predicted.Comment: 23 pages, RevTex, 19 eps figures, revised versio

Boundary and Coulomb Effects on Boson Systems in High-Energy Heavy-Ion Collisions

The boundary of a boson system plays an important role in determining the momentum distribution of the bosons. For a boson system with a cylindrical boundary, the momentum distribution is enhanced at high transverse momenta but suppressed at low transverse momenta, relative to a Bose-Einstein distribution. The boundary effects on systems of massless gluons and massive pions are studied. For gluons in a quark-gluon plasma, the presence of the boundary may modify the signals for the quark-gluon plasma. For pions in a pion system in heavy-ion collisions, Coulomb final-state interactions with the nuclear participants in the vicinity of the central rapidity region further modify the momentum distribution at low transverse momenta. By including both the boundary effect and the Coulomb final-state interactions we are able to account for the behavior of the $\pi^{-}$ transverse momentum spectrum observed in many heavy-ion experiments, notably at low transverse momenta.Comment: 15 pages Postscript uuencoded tar-comprssed file, 9 Postscript figures uuencoded tar-compressed fil