Fragmentation Function in Non-Equilibrium QCD Using Closed-Time Path Integral Formalism

In this paper we implement Schwinger-Keldysh closed-time path integral formalism in non-equilibrium QCD to the definition of Collins-Soper fragmentation function. We consider a high p_T parton in QCD medium at initial time t_0 with arbitrary non-equilibrium (non-isotropic) distribution function f(\vec{p}) fragmenting to hadron. We formulate parton to hadron fragmentation function in non-equilibrium QCD in the light-cone quantization formalism. It may be possible to include final state interactions with the medium via modification of the Wilson lines in this definition of the non-equilibrium fragmentation function. This may be relevant to study hadron production from quark-gluon plasma at RHIC and LHC.Comment: 15 pages latex, Accepted for Publication in European Physical Journal

Assessing the significance of changes in ENSO amplitude using variance metrics

© Copyright 2014 American Meteorological Society (AMS). Permission to use figures, tables, and brief excerpts from this work in scientific and educational works is hereby granted provided that the source is acknowledged. Any use of material in this work that is determined to be “fair use” under Section 107 of the U.S. Copyright Act September 2010 Page 2 or that satisfies the conditions specified in Section 108 of the U.S. Copyright Act (17 USC §108, as revised by P.L. 94-553) does not require the AMS’s permission. Republication, systematic reproduction, posting in electronic form, such as on a web site or in a searchable database, or other uses of this material, except as exempted by the above statement, requires written permission or a license from the AMS. Additional details are provided in the AMS Copyright Policy, available on the AMS Web site located at (http://www.ametsoc.org/) or from the AMS at 617-227-2425 or [email protected] variance of time series records relating to ENSO, such as the interannual anomalies or bandpass filtered components of equatorial Pacific SST indices, provides one approach to quantifying changes in ENSO amplitude. Robust assessment of the significance of changes in amplitude defined in this way is, however, hampered by uncertainty regarding the sampling distributions of such variance metrics within an unforced climate system. The present study shows that the empirical constraints on these sampling distributions provided by a range of unforced CGCM simulations are consistent with the expected parametric form, suggesting that standard parametric testing strategies can be robustly applied, even in the case of the nonlinear ENSO system. Under such an approach, the sampling distribution of unforced relative changes in variance may be constrained by a single parameter τd: the value of which depends on the choice of method used to extract the ENSO-related component of time series variability. In the case of interannual anomaly records, the value of τd is also substantially dependent on the overall spectral properties of the climatic variable under consideration. In contrast, the τd value for bandpass filtered records can be conservatively constrained from the lower edge of the filter passband, allowing for the direct but robust assessment of the significance of relative changes in ENSO amplitude, regardless of the climatic variable under consideration. Example applications of this approach confirm marginally significant F-test p values for multidecadal changes in central Pacific instrumental SST variance and highly significant ones for centennial changes in central Pacific coral δ18O variance. © 2014 American Meteorological Society.Natural Environment Research Council (NERC

Mechanical nociceptive threshold testing in Bos indicus bull calves

The aim of this prospective, controlled, randomised trial was to develop a technique for mechanical nociceptive threshold testing (NTT) to assess pain in Bos indicus bull calves undergoing surgical castration. Analgesia was provided by 0.5 mg/kg subcutaneous (SC) meloxicam (M) and/or 2 mg/kg of intra-testicular and SC (at the surgery sites) lidocaine (L). Forty-eight Brahman bull calves at 6–8 months of age were divided into six study groups, each with eight animals: no surgery control; surgical castration (C) without analgesia; C and Mpre-op; C and Mpost-op; C, L and Mpost-op; C and L. Mechanical NTT was performed the day before surgery (Day –1) and on Days 1, 2, 6, 10 and 13 after surgery. A handheld manual pneumatic device with a 1-mm (diameter) blunt pin was used to deliver a mechanical stimulus to a maximum of 27 Newtons either side of the most dorsal aspect of the sacrum. The most frequent responses to the mechanical stimulus were lifting or kicking of the leg on the same side as the stimulus (31%) and stepping away from the stimulus (24.9%). Data were analysed with a mixed effect linear model with the nociceptive threshold (NT) as the response variable and day and analgesic treatment as predictors (P < 0.05 was considered significant). For all groups, there was a trend towards decreasing NT over the study period but there were no significant differences between groups. Step down model selection with day, batch and treatment terms revealed a significant effect of day (P < 0.001) and batch (P = 0.007). Mechanical NTT for assessment of pain in Bos indicus bull calves requires further refinement to determine if this is a useful method of pain assessment

Qualitative Behavioural Assessment of Bos indicus cattle after surgical castration

There are various methods to perform castration of cattle, but surgical castration is the most common. Although it is well documented that surgical procedures inflict pain, analgesic use is usually omitted for surgical castration of production animals in Australia. This study compares the behavioural responses of castrated cattle (C) with non-castrated (NC) controls, and C with those castrated and given lignocaine and meloxicam (CLM) for analgesia. Brahman bull calves (n = 8 for each treatment) were filmed in the morning pre- (day -1) and post- (day +1) castration in the paddock and feed yard (‘context’ of observation). Over four sessions, volunteer observers viewed the video footage for Qualitative Behaviour Analysis (QBA) using the Free Choice Profiling methodology comparing C and NC cattle, and C and CLM cattle under both contexts. The QBA consensus profiles explained 37.4% (C vs. NC) and 40.6% (C vs. CLM) of variation among observers for paddock sessions and 34.7% (C vs. NC) and 38.7% (C vs. CLM) for feed yard sessions. Significant treatment x day interaction effects were recorded in the paddock (P = 0.007 and P < 0.001) and yard (P =  0.004 and P =  0.025) contexts for comparisons between NC vs C, and C vs CLM respectively. Compared to NC, post-castration C cattle were described as more ‘bored’/’lethargic’ and ‘alone’ (paddock) and were more ‘calm’/’relaxed’ and ‘relaxed’/’lonely’ (yard). Similarly, compared to CLM, post-castration C cattle were described as more ‘docile’/’chilled’ and ‘curious’/’aware’ (paddock) and were less ‘hungry’/’alert’ (yard). There was only one correlation between qualitative and quantitative behaviour scoring; ruminating showed significant correlation with one dimension in each context, that reflected a positive emotion (‘calm, relaxed’). The comparison between C vs. NC suggest that C were less active and less engaged with their environment compared to the NC group following castration. The C vs. CLM comparison suggests a more subtle response whereby analgesia was associated with more positive valence (higher scores on ‘calm/comfortable’, and ‘hungry/alert’ dimensions) following castration. The interpretation of findings requires careful consideration of the emotional responses given these calves were unhabituated and reactive to their surroundings. These results suggest the body language of Bos indicus cattle may reveal indicators of pain, and that the administration of analgesia may be beneficial at the time of castration. The study highlights the complexities and challenges of identifying pain responses in Brahman cattle

Restoration of kTk_T factorization for low pTp_T hadron hadroproduction

We discuss the applicability of the $k_T$ factorization theorem to low-$p_T$ hadron production in hadron-hadron collision in a simple toy model, which involves only scalar particles and gluons. It has been shown that the $k_T$ factorization for high-$p_T$ hadron hadroproduction is broken by soft gluons in the Glauber region, which are exchanged among a transverse-momentum-dependent (TMD) parton density and other subprocesses of the collision. We explain that the contour of a loop momentum can be deformed away from the Glauber region at low $p_T$, so the above residual infrared divergence is factorized by means of the standard eikonal approximation. The $k_T$ factorization is then restored in the sense that a TMD parton density maintains its universality. Because the resultant Glauber factor is independent of hadron flavors, experimental constraints on its behavior are possible. The $k_T$ factorization can also be restored for the transverse single-spin asymmetry in hadron-hadron collision at low $p_T$ in a similar way, with the residual infrared divergence being factorized into the same Glauber factor.Comment: 12 pages, 2 figures, version to appear in EPJ

Mitigation of electroencephalographic and cardiovascular responses to castration in Bos indicus bulls following the administration of either lidocaine or meloxicam

Objective To investigate the mitigating effects of administration of local or systemic meloxicam on the electroencephalographic (EEG) and cardiovascular responses during surgical castration of Bos indicus bull calves. Study design Prospective, randomized, experimental study. Animals Thirty-six 6–8 month-old Bos indicus bull calves, with a mean ± standard deviation weight of 237 ± 19 kg. Methods Animals were randomly allocated to three groups of 12 (group L, 260 mg of 2% lidocaine subcutaneously and intratesticularly 5 minutes prior to castration; group M, 0.5 mg kg−1 of meloxicam subcutaneously 30 minutes prior to castration; group C, no pre-operative analgesia administered). Anaesthesia was induced and maintained with halothane (0.9–1.1%) in oxygen. Electroencephalogram, heart rate (HR) and mean blood pressure (MAP) were recorded for 300 seconds prior to (baseline, B) and from the start of surgery (first testicle incision, T1). HR and MAP were compared at 10 second intervals for 90 seconds from the start of T1. Median frequency (F50), spectral edge frequency (F95) and total power of the EEG (Ptot) were analysed using area under the curve comparing T1 to B. Results All EEG variables were significantly different between B and T1 (p ≤ 0.0001). No differences in F50 were found between groups during T1 (p = 0.6491). F95 and Ptot were significantly different between group L and groups C and M during T1 (p = 0.0005 and 0.0163, respectively). There were transient significant changes in HR and MAP in groups L and M compared to group C during the 20–50 second periods. Conclusions The EEG changes indicate nociceptive responses in all three groups during surgical castration, greater in group L compared to groups C and M. Both analgesics attenuated the peracute cardiovascular response. Lidocaine and meloxicam administered prior to castration attenuated these responses in Bos indicus bull calves. Clinical relevance These findings provide support for the pre-operative administration of lidocaine and potentially meloxicam for castration in Bos indicus bull calves

The C parameter distribution in e+e- annihilation

We study perturbative and non-perturbative aspects of the distribution of the C parameter in e+e- annihilation using renormalon techniques. We perform an exact calculation of the characteristic function, corresponding to the C parameter differential cross section for a single off-shell gluon. We then concentrate on the two-jet region, derive the Borel representation of the Sudakov exponent in the large-beta_0 limit and compare the result to that of the thrust T. Analysing the exponent, we distinguish two ingredients: the jet function, depending on Q^2C, summarizing the effects of collinear radiation, and a function describing soft emission at large angles, with momenta of order QC. The former is the same as for the thrust upon scaling C by 1/6, whereas the latter is different. We verify that the rescaled C distribution coincides with that of 1-T to next-to-leading logarithmic accuracy, as predicted by Catani and Webber, and demonstrate that this relation breaks down beyond this order owing to soft radiation at large angles. The pattern of power corrections is also similar to that of the thrust: corrections appear as odd powers of Lambda/(QC). Based on the size of the renormalon ambiguity, however, the shape function is different: subleading power corrections for the C distribution appear to be significantly smaller than those for the thrust.Comment: 24 pages, Latex (using JHEP3.cls), 1 postscript figur

On the mechanisms of heavy-quarkonium hadroproduction

We discuss the various mechanisms potentially at work in hadroproduction of heavy quarkonia in the light of computations of higher-order QCD corrections both in the Colour-Singlet (CS) and Colour-Octet (CO) channels and the inclusion of the contribution arising from the s-channel cut in the CS channel. We also discuss new observables meant to better discriminate between these different mechanisms.Comment: Invited review talk at 3rd International Conference On Hard And Electromagnetic Probes Of High-Energy Nuclear Collisions (HP2008), 8-14 June 2008, Illa da Toxa, Galicia, Spain. 11 pages, 21 figures, LaTeX, uses svjour.cls and svepj.clo (included

On the all-order perturbative finiteness of the deformed N=4 SYM theory

We prove that the chiral propagator of the deformed N=4 SYM theory can be made finite to all orders in perturbation theory for any complex value of the deformation parameter. For any such value the set of finite deformed theories can be parametrized by a whole complex function of the coupling constant g. We reveal a new protection mechanism for chiral operators of dimension three. These are obtained by differentiating the Lagrangian with respect to the independent coupling constants. A particular combination of them is a CPO involving only chiral matter. Its all-order form is derived directly from the finiteness condition. The procedure is confirmed perturbatively through order g^6.Comment: LaTeX, 28 pages, 5 figure

Attachment Styles Within the Coach-Athlete Dyad: Preliminary Investigation and Assessment Development

The present preliminary study aimed to develop and examine the psychometric properties of a new sport-specific self-report instrument designed to assess athletes’ and coaches’ attachment styles. The development and initial validation comprised three main phases. In Phase 1, a pool of items was generated based on pre-existing self-report attachment instruments, modified to reflect a coach and an athlete’s style of attachment. In Phase 2, the content validity of the items was assessed by a panel of experts. A final scale was developed and administered to 405 coaches and 298 athletes (N = 703 participants). In Phase 3, confirmatory factor analysis of the obtained data was conducted to determine the final items of the Coach-Athlete Attachment Scale (CAAS). Confirmatory factor analysis revealed acceptable goodness of fit indexes for a 3-first order factor model as well as a 2-first order factor model for both the athlete and the coach data, respectively. A secure attachment style positively predicted relationship satisfaction, while an insecure attachment style was a negative predictor of relationship satisfaction. The CAAS revealed initial psychometric properties of content, factorial, and predictive validity, as well as reliability