Medium modification of jet fragmentation in Au+Au collisions at √[s(NN)]=200 GeV measured in direct photon-hadron correlations

The jet fragmentation function is measured with direct photon-hadron correlations in p+p and Au+Au collisions at √[s(NN)]=200 GeV. The p(T) of the photon is an excellent approximation to the initial p(T) of the jet and the ratio z(T)=p(T)(h)/p(T)(γ) is used as a proxy for the jet fragmentation function. A statistical subtraction is used to extract the direct photon-hadron yields in Au+Au collisions while a photon isolation cut is applied in p+p. I(AA), the ratio of hadron yield opposite the photon in Au+Au to that in p+p, indicates modification of the jet fragmentation function. Suppression, most likely due to energy loss in the medium, is seen at high z(T). The associated hadron yield at low z(T) is enhanced at large angles. Such a trend is expected from redistribution of the lost energy into increased production of low-momentum particles.

Validation of the cephalosporin intradermal skin test for predicting immediate hypersensitivity: a prospective study with drug challenge

BACKGROUND

Cephalosporin is a major offending agent in terms of drug hypersensitivity along with penicillin. Cephalosporin intradermal skin tests (IDTs) have been widely used; however, their validity for predicting immediate hypersensitivity has not been studied. This study aimed to determine the predictive value of cephalosporin intradermal skin testing before administration of the drug.

METHODS

We prospectively conducted IDTs with four cephalosporins, one each of selected first-, second-, third-, or fourth-generation cephalosporins: ceftezol; cefotetan or cefamandole; ceftriaxone or cefotaxime; and flomoxef, respectively, as well as with penicillin G. After the skin test, whatever the result, one of the tested cephalosporins was administered intravenously and the patient was carefully observed.

RESULTS

We recruited 1421 patients who required preoperative cephalosporins. Seventy-four patients (74/1421, 5.2%) were positive to at least one cephalosporin. However, none of responders had immediate hypersensitivity reactions after a challenge dose of the same or different cephalosporin, which were positive in the skin test. Four patients who suffered generalized urticaria and itching after challenge gave negative skin tests for the corresponding drug. The IDT for cephalosporin had a sensitivity of 0%, a specificity of 97.5%, a negative predictive value of 99.7%, and a positive predictive value (PPV) of 0%, when challenged with the same drugs that were positive in the skin test.

CONCLUSION

Routine skin testing with a cephalosporin before its administration is not useful for predicting immediate hypersensitivity because of the extremely low sensitivity and PPV of the skin test (CRIS registration no. KCT0000455).

Patterns and predictors of non-use of family planning methods in Ethiopian women: a panel survey

PURPOSE

Family planning (FP) is a key global health issue for achieving millennium development goals by 2015. The aim of this study was to identify predictors of changes in FP practice before and after interventions among Ethiopian women of reproductive age in a rural area.

METHODS

This study used a panel survey to identify predictors that placed women at greater risk for non-use of FP methods. The sample consisted of 407 women aged 19-49 years old living in a rural community of Ethiopia who completed both a baseline and follow-up survey. Trained local enumerators conducted face-to-face interviews during home visits. Patterns of FP practice were categorized into four groups: FP use at both baseline and follow-up; use at baseline but non-use at follow-up; non-use at baseline but use at follow-up; non-use at both baseline and follow-up. Logistic regression and classification and regression tree analyses were used.

RESULTS

In a binary logistic regression, women over 35 years old with a negative attitude towards FP and resided in the Sibu area were less likely to start FP practice. Women over 35 years who were in poor health and resided in Sibu were less likely to continue FP practice. For the decision tree, age was the primary node for FP non-users at baseline while area of residence was the primary node for FP users at baseline.

CONCLUSION

Age, health status, attitude towards FP, and area of residence are the primary considerations when developing FP interventions for Ethiopian women in a resource-limited rural area.

The impact of total antioxidant capacity on pulmonary function in asthma patients

BACKGROUND

Oxidative stress, mediated by an imbalance between oxidants and antioxidants, contributes significantly to the pathogenesis of asthma.

OBJECTIVE

To evaluate the impact of serum total antioxidant capacity (TAC) on the pulmonary function of Korean asthma patients.

METHOD

A total of 104 adult asthma patients enrolled from the COREA (Cohort for Reality and Evolution of Adult Asthma in Korea) programme participated in the study. Baseline clinical parameters at enrolment, and the results of pulmonary function tests at baseline and 1 and 2 years after enrolment were collected. TAC at baseline was measured using a Trolox-equivalent antioxidant capacity assay. Patients were divided into two groups based on TAC levels, and various clinical parameters were compared.

RESULT

Serum TAC levels correlated with forced expiratory volume in 1 second (FEV(1)) at baseline (r = 0.22, P = 0.03). The group with higher baseline TAC levels maintained greater mean FEV(1) both 1 and 2 years after enrolment, even after adjusting for sex, age, height, weight, body mass index and smoking status.

CONCLUSION

These results suggest an important link between serum TAC levels and pulmonary function, indicating that higher TAC levels may be a biomarker for favourable prognosis in asthma patients.

Comparison of azimuthal ion velocity profiles using Mach probes, time delay estimation, and laser induced fluorescence in a linear plasma device

We compare measurements of radially sheared azimuthal plasma flow based on time delay estimation (TDE) between two spatially separated Langmuir probes, Mach probes and laser induced fluorescence (LIF). TDE measurements cannot distinguish between ion fluid velocities and phase velocities. TDE and Mach probes are perturbative, so we compare the results against LIF, a non-perturbative, spatially resolved diagnostic technique that provides direct measurements of the ion velocity distribution functions. The bulk ion flow is determined from the Doppler shift of the Argon absorption line at 668.6139 nm. We compare results from all the three diagnostics, at various magnetic fields, which acts as a control knob for development of drift wave turbulence. We find that while Mach probes and LIF give similar profiles, TDE measurements typically overestimate the velocities and are also sensitive to the drift wave modes being investigated.